diff -Nur linux-3.18.14.orig/arch/alpha/mm/fault.c linux-3.18.14-rt/arch/alpha/mm/fault.c --- linux-3.18.14.orig/arch/alpha/mm/fault.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/alpha/mm/fault.c 2015-05-31 15:32:45.517635394 -0500 @@ -107,7 +107,7 @@ /* If we're in an interrupt context, or have no user context, we must not take the fault. */ - if (!mm || in_atomic()) + if (!mm || pagefault_disabled()) goto no_context; #ifdef CONFIG_ALPHA_LARGE_VMALLOC diff -Nur linux-3.18.14.orig/arch/arm/include/asm/cmpxchg.h linux-3.18.14-rt/arch/arm/include/asm/cmpxchg.h --- linux-3.18.14.orig/arch/arm/include/asm/cmpxchg.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/arm/include/asm/cmpxchg.h 2015-05-31 15:32:45.557635393 -0500 @@ -129,6 +129,8 @@ #else /* min ARCH >= ARMv6 */ +#define __HAVE_ARCH_CMPXCHG 1 + extern void __bad_cmpxchg(volatile void *ptr, int size); /* diff -Nur linux-3.18.14.orig/arch/arm/include/asm/futex.h linux-3.18.14-rt/arch/arm/include/asm/futex.h --- linux-3.18.14.orig/arch/arm/include/asm/futex.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/arm/include/asm/futex.h 2015-05-31 15:32:45.561635393 -0500 @@ -93,6 +93,8 @@ if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32))) return -EFAULT; + preempt_disable_rt(); + __asm__ __volatile__("@futex_atomic_cmpxchg_inatomic\n" "1: " TUSER(ldr) " %1, [%4]\n" " teq %1, %2\n" @@ -104,6 +106,8 @@ : "cc", "memory"); *uval = val; + + preempt_enable_rt(); return ret; } diff -Nur linux-3.18.14.orig/arch/arm/include/asm/switch_to.h linux-3.18.14-rt/arch/arm/include/asm/switch_to.h --- linux-3.18.14.orig/arch/arm/include/asm/switch_to.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/arm/include/asm/switch_to.h 2015-05-31 15:32:45.565635393 -0500 @@ -3,6 +3,13 @@ #include +#if defined CONFIG_PREEMPT_RT_FULL && defined CONFIG_HIGHMEM +void switch_kmaps(struct task_struct *prev_p, struct task_struct *next_p); +#else +static inline void +switch_kmaps(struct task_struct *prev_p, struct task_struct *next_p) { } +#endif + /* * For v7 SMP cores running a preemptible kernel we may be pre-empted * during a TLB maintenance operation, so execute an inner-shareable dsb @@ -22,6 +29,7 @@ #define switch_to(prev,next,last) \ do { \ + switch_kmaps(prev, next); \ last = __switch_to(prev,task_thread_info(prev), task_thread_info(next)); \ } while (0) diff -Nur linux-3.18.14.orig/arch/arm/include/asm/thread_info.h linux-3.18.14-rt/arch/arm/include/asm/thread_info.h --- linux-3.18.14.orig/arch/arm/include/asm/thread_info.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/arm/include/asm/thread_info.h 2015-05-31 15:32:45.585635393 -0500 @@ -51,6 +51,7 @@ struct thread_info { unsigned long flags; /* low level flags */ int preempt_count; /* 0 => preemptable, <0 => bug */ + int preempt_lazy_count; /* 0 => preemptable, <0 => bug */ mm_segment_t addr_limit; /* address limit */ struct task_struct *task; /* main task structure */ struct exec_domain *exec_domain; /* execution domain */ @@ -149,6 +150,7 @@ #define TIF_SIGPENDING 0 #define TIF_NEED_RESCHED 1 #define TIF_NOTIFY_RESUME 2 /* callback before returning to user */ +#define TIF_NEED_RESCHED_LAZY 3 #define TIF_UPROBE 7 #define TIF_SYSCALL_TRACE 8 #define TIF_SYSCALL_AUDIT 9 @@ -162,6 +164,7 @@ #define _TIF_SIGPENDING (1 << TIF_SIGPENDING) #define _TIF_NEED_RESCHED (1 << TIF_NEED_RESCHED) #define _TIF_NOTIFY_RESUME (1 << TIF_NOTIFY_RESUME) +#define _TIF_NEED_RESCHED_LAZY (1 << TIF_NEED_RESCHED_LAZY) #define _TIF_UPROBE (1 << TIF_UPROBE) #define _TIF_SYSCALL_TRACE (1 << TIF_SYSCALL_TRACE) #define _TIF_SYSCALL_AUDIT (1 << TIF_SYSCALL_AUDIT) diff -Nur linux-3.18.14.orig/arch/arm/Kconfig linux-3.18.14-rt/arch/arm/Kconfig --- linux-3.18.14.orig/arch/arm/Kconfig 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/arm/Kconfig 2015-05-31 15:32:45.529635394 -0500 @@ -62,6 +62,7 @@ select HAVE_PERF_EVENTS select HAVE_PERF_REGS select HAVE_PERF_USER_STACK_DUMP + select HAVE_PREEMPT_LAZY select HAVE_RCU_TABLE_FREE if (SMP && ARM_LPAE) select HAVE_REGS_AND_STACK_ACCESS_API select HAVE_SYSCALL_TRACEPOINTS diff -Nur linux-3.18.14.orig/arch/arm/kernel/asm-offsets.c linux-3.18.14-rt/arch/arm/kernel/asm-offsets.c --- linux-3.18.14.orig/arch/arm/kernel/asm-offsets.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/arm/kernel/asm-offsets.c 2015-05-31 15:32:45.605635393 -0500 @@ -64,6 +64,7 @@ BLANK(); DEFINE(TI_FLAGS, offsetof(struct thread_info, flags)); DEFINE(TI_PREEMPT, offsetof(struct thread_info, preempt_count)); + DEFINE(TI_PREEMPT_LAZY, offsetof(struct thread_info, preempt_lazy_count)); DEFINE(TI_ADDR_LIMIT, offsetof(struct thread_info, addr_limit)); DEFINE(TI_TASK, offsetof(struct thread_info, task)); DEFINE(TI_EXEC_DOMAIN, offsetof(struct thread_info, exec_domain)); diff -Nur linux-3.18.14.orig/arch/arm/kernel/entry-armv.S linux-3.18.14-rt/arch/arm/kernel/entry-armv.S --- linux-3.18.14.orig/arch/arm/kernel/entry-armv.S 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/arm/kernel/entry-armv.S 2015-05-31 15:32:45.613635393 -0500 @@ -207,11 +207,18 @@ #ifdef CONFIG_PREEMPT get_thread_info tsk ldr r8, [tsk, #TI_PREEMPT] @ get preempt count - ldr r0, [tsk, #TI_FLAGS] @ get flags teq r8, #0 @ if preempt count != 0 + bne 1f @ return from exeption + ldr r0, [tsk, #TI_FLAGS] @ get flags + tst r0, #_TIF_NEED_RESCHED @ if NEED_RESCHED is set + blne svc_preempt @ preempt! + + ldr r8, [tsk, #TI_PREEMPT_LAZY] @ get preempt lazy count + teq r8, #0 @ if preempt lazy count != 0 movne r0, #0 @ force flags to 0 - tst r0, #_TIF_NEED_RESCHED + tst r0, #_TIF_NEED_RESCHED_LAZY blne svc_preempt +1: #endif svc_exit r5, irq = 1 @ return from exception @@ -226,6 +233,8 @@ 1: bl preempt_schedule_irq @ irq en/disable is done inside ldr r0, [tsk, #TI_FLAGS] @ get new tasks TI_FLAGS tst r0, #_TIF_NEED_RESCHED + bne 1b + tst r0, #_TIF_NEED_RESCHED_LAZY reteq r8 @ go again b 1b #endif diff -Nur linux-3.18.14.orig/arch/arm/kernel/process.c linux-3.18.14-rt/arch/arm/kernel/process.c --- linux-3.18.14.orig/arch/arm/kernel/process.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/arm/kernel/process.c 2015-05-31 15:32:45.617635393 -0500 @@ -437,6 +437,30 @@ } #ifdef CONFIG_MMU +/* + * CONFIG_SPLIT_PTLOCK_CPUS results in a page->ptl lock. If the lock is not + * initialized by pgtable_page_ctor() then a coredump of the vector page will + * fail. + */ +static int __init vectors_user_mapping_init_page(void) +{ + struct page *page; + unsigned long addr = 0xffff0000; + pgd_t *pgd; + pud_t *pud; + pmd_t *pmd; + + pgd = pgd_offset_k(addr); + pud = pud_offset(pgd, addr); + pmd = pmd_offset(pud, addr); + page = pmd_page(*(pmd)); + + pgtable_page_ctor(page); + + return 0; +} +late_initcall(vectors_user_mapping_init_page); + #ifdef CONFIG_KUSER_HELPERS /* * The vectors page is always readable from user space for the diff -Nur linux-3.18.14.orig/arch/arm/kernel/process.c.orig linux-3.18.14-rt/arch/arm/kernel/process.c.orig --- linux-3.18.14.orig/arch/arm/kernel/process.c.orig 1969-12-31 18:00:00.000000000 -0600 +++ linux-3.18.14-rt/arch/arm/kernel/process.c.orig 2015-05-20 10:04:50.000000000 -0500 @@ -0,0 +1,560 @@ +/* + * linux/arch/arm/kernel/process.c + * + * Copyright (C) 1996-2000 Russell King - Converted to ARM. + * Original Copyright (C) 1995 Linus Torvalds + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ +#include + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include +#include +#include +#include +#include +#include +#include +#include "reboot.h" + +#ifdef CONFIG_CC_STACKPROTECTOR +#include +unsigned long __stack_chk_guard __read_mostly; +EXPORT_SYMBOL(__stack_chk_guard); +#endif + +static const char *processor_modes[] __maybe_unused = { + "USER_26", "FIQ_26" , "IRQ_26" , "SVC_26" , "UK4_26" , "UK5_26" , "UK6_26" , "UK7_26" , + "UK8_26" , "UK9_26" , "UK10_26", "UK11_26", "UK12_26", "UK13_26", "UK14_26", "UK15_26", + "USER_32", "FIQ_32" , "IRQ_32" , "SVC_32" , "UK4_32" , "UK5_32" , "UK6_32" , "ABT_32" , + "UK8_32" , "UK9_32" , "UK10_32", "UND_32" , "UK12_32", "UK13_32", "UK14_32", "SYS_32" +}; + +static const char *isa_modes[] __maybe_unused = { + "ARM" , "Thumb" , "Jazelle", "ThumbEE" +}; + +extern void call_with_stack(void (*fn)(void *), void *arg, void *sp); +typedef void (*phys_reset_t)(unsigned long); + +/* + * A temporary stack to use for CPU reset. This is static so that we + * don't clobber it with the identity mapping. When running with this + * stack, any references to the current task *will not work* so you + * should really do as little as possible before jumping to your reset + * code. + */ +static u64 soft_restart_stack[16]; + +static void __soft_restart(void *addr) +{ + phys_reset_t phys_reset; + + /* Take out a flat memory mapping. */ + setup_mm_for_reboot(); + + /* Clean and invalidate caches */ + flush_cache_all(); + + /* Turn off caching */ + cpu_proc_fin(); + + /* Push out any further dirty data, and ensure cache is empty */ + flush_cache_all(); + + /* Switch to the identity mapping. */ + phys_reset = (phys_reset_t)(unsigned long)virt_to_phys(cpu_reset); + phys_reset((unsigned long)addr); + + /* Should never get here. */ + BUG(); +} + +void _soft_restart(unsigned long addr, bool disable_l2) +{ + u64 *stack = soft_restart_stack + ARRAY_SIZE(soft_restart_stack); + + /* Disable interrupts first */ + raw_local_irq_disable(); + local_fiq_disable(); + + /* Disable the L2 if we're the last man standing. */ + if (disable_l2) + outer_disable(); + + /* Change to the new stack and continue with the reset. */ + call_with_stack(__soft_restart, (void *)addr, (void *)stack); + + /* Should never get here. */ + BUG(); +} + +void soft_restart(unsigned long addr) +{ + _soft_restart(addr, num_online_cpus() == 1); +} + +/* + * Function pointers to optional machine specific functions + */ +void (*pm_power_off)(void); +EXPORT_SYMBOL(pm_power_off); + +void (*arm_pm_restart)(enum reboot_mode reboot_mode, const char *cmd); + +/* + * This is our default idle handler. + */ + +void (*arm_pm_idle)(void); + +/* + * Called from the core idle loop. + */ + +void arch_cpu_idle(void) +{ + if (arm_pm_idle) + arm_pm_idle(); + else + cpu_do_idle(); + local_irq_enable(); +} + +void arch_cpu_idle_prepare(void) +{ + local_fiq_enable(); +} + +void arch_cpu_idle_enter(void) +{ + ledtrig_cpu(CPU_LED_IDLE_START); +#ifdef CONFIG_PL310_ERRATA_769419 + wmb(); +#endif +} + +void arch_cpu_idle_exit(void) +{ + ledtrig_cpu(CPU_LED_IDLE_END); +} + +#ifdef CONFIG_HOTPLUG_CPU +void arch_cpu_idle_dead(void) +{ + cpu_die(); +} +#endif + +/* + * Called by kexec, immediately prior to machine_kexec(). + * + * This must completely disable all secondary CPUs; simply causing those CPUs + * to execute e.g. a RAM-based pin loop is not sufficient. This allows the + * kexec'd kernel to use any and all RAM as it sees fit, without having to + * avoid any code or data used by any SW CPU pin loop. The CPU hotplug + * functionality embodied in disable_nonboot_cpus() to achieve this. + */ +void machine_shutdown(void) +{ + disable_nonboot_cpus(); +} + +/* + * Halting simply requires that the secondary CPUs stop performing any + * activity (executing tasks, handling interrupts). smp_send_stop() + * achieves this. + */ +void machine_halt(void) +{ + local_irq_disable(); + smp_send_stop(); + + local_irq_disable(); + while (1); +} + +/* + * Power-off simply requires that the secondary CPUs stop performing any + * activity (executing tasks, handling interrupts). smp_send_stop() + * achieves this. When the system power is turned off, it will take all CPUs + * with it. + */ +void machine_power_off(void) +{ + local_irq_disable(); + smp_send_stop(); + + if (pm_power_off) + pm_power_off(); +} + +/* + * Restart requires that the secondary CPUs stop performing any activity + * while the primary CPU resets the system. Systems with a single CPU can + * use soft_restart() as their machine descriptor's .restart hook, since that + * will cause the only available CPU to reset. Systems with multiple CPUs must + * provide a HW restart implementation, to ensure that all CPUs reset at once. + * This is required so that any code running after reset on the primary CPU + * doesn't have to co-ordinate with other CPUs to ensure they aren't still + * executing pre-reset code, and using RAM that the primary CPU's code wishes + * to use. Implementing such co-ordination would be essentially impossible. + */ +void machine_restart(char *cmd) +{ + local_irq_disable(); + smp_send_stop(); + + if (arm_pm_restart) + arm_pm_restart(reboot_mode, cmd); + else + do_kernel_restart(cmd); + + /* Give a grace period for failure to restart of 1s */ + mdelay(1000); + + /* Whoops - the platform was unable to reboot. Tell the user! */ + printk("Reboot failed -- System halted\n"); + local_irq_disable(); + while (1); +} + +void __show_regs(struct pt_regs *regs) +{ + unsigned long flags; + char buf[64]; + + show_regs_print_info(KERN_DEFAULT); + + print_symbol("PC is at %s\n", instruction_pointer(regs)); + print_symbol("LR is at %s\n", regs->ARM_lr); + printk("pc : [<%08lx>] lr : [<%08lx>] psr: %08lx\n" + "sp : %08lx ip : %08lx fp : %08lx\n", + regs->ARM_pc, regs->ARM_lr, regs->ARM_cpsr, + regs->ARM_sp, regs->ARM_ip, regs->ARM_fp); + printk("r10: %08lx r9 : %08lx r8 : %08lx\n", + regs->ARM_r10, regs->ARM_r9, + regs->ARM_r8); + printk("r7 : %08lx r6 : %08lx r5 : %08lx r4 : %08lx\n", + regs->ARM_r7, regs->ARM_r6, + regs->ARM_r5, regs->ARM_r4); + printk("r3 : %08lx r2 : %08lx r1 : %08lx r0 : %08lx\n", + regs->ARM_r3, regs->ARM_r2, + regs->ARM_r1, regs->ARM_r0); + + flags = regs->ARM_cpsr; + buf[0] = flags & PSR_N_BIT ? 'N' : 'n'; + buf[1] = flags & PSR_Z_BIT ? 'Z' : 'z'; + buf[2] = flags & PSR_C_BIT ? 'C' : 'c'; + buf[3] = flags & PSR_V_BIT ? 'V' : 'v'; + buf[4] = '\0'; + +#ifndef CONFIG_CPU_V7M + printk("Flags: %s IRQs o%s FIQs o%s Mode %s ISA %s Segment %s\n", + buf, interrupts_enabled(regs) ? "n" : "ff", + fast_interrupts_enabled(regs) ? "n" : "ff", + processor_modes[processor_mode(regs)], + isa_modes[isa_mode(regs)], + get_fs() == get_ds() ? "kernel" : "user"); +#else + printk("xPSR: %08lx\n", regs->ARM_cpsr); +#endif + +#ifdef CONFIG_CPU_CP15 + { + unsigned int ctrl; + + buf[0] = '\0'; +#ifdef CONFIG_CPU_CP15_MMU + { + unsigned int transbase, dac; + asm("mrc p15, 0, %0, c2, c0\n\t" + "mrc p15, 0, %1, c3, c0\n" + : "=r" (transbase), "=r" (dac)); + snprintf(buf, sizeof(buf), " Table: %08x DAC: %08x", + transbase, dac); + } +#endif + asm("mrc p15, 0, %0, c1, c0\n" : "=r" (ctrl)); + + printk("Control: %08x%s\n", ctrl, buf); + } +#endif +} + +void show_regs(struct pt_regs * regs) +{ + __show_regs(regs); + dump_stack(); +} + +ATOMIC_NOTIFIER_HEAD(thread_notify_head); + +EXPORT_SYMBOL_GPL(thread_notify_head); + +/* + * Free current thread data structures etc.. + */ +void exit_thread(void) +{ + thread_notify(THREAD_NOTIFY_EXIT, current_thread_info()); +} + +void flush_thread(void) +{ + struct thread_info *thread = current_thread_info(); + struct task_struct *tsk = current; + + flush_ptrace_hw_breakpoint(tsk); + + memset(thread->used_cp, 0, sizeof(thread->used_cp)); + memset(&tsk->thread.debug, 0, sizeof(struct debug_info)); + memset(&thread->fpstate, 0, sizeof(union fp_state)); + + flush_tls(); + + thread_notify(THREAD_NOTIFY_FLUSH, thread); +} + +void release_thread(struct task_struct *dead_task) +{ +} + +asmlinkage void ret_from_fork(void) __asm__("ret_from_fork"); + +int +copy_thread(unsigned long clone_flags, unsigned long stack_start, + unsigned long stk_sz, struct task_struct *p) +{ + struct thread_info *thread = task_thread_info(p); + struct pt_regs *childregs = task_pt_regs(p); + + memset(&thread->cpu_context, 0, sizeof(struct cpu_context_save)); + + if (likely(!(p->flags & PF_KTHREAD))) { + *childregs = *current_pt_regs(); + childregs->ARM_r0 = 0; + if (stack_start) + childregs->ARM_sp = stack_start; + } else { + memset(childregs, 0, sizeof(struct pt_regs)); + thread->cpu_context.r4 = stk_sz; + thread->cpu_context.r5 = stack_start; + childregs->ARM_cpsr = SVC_MODE; + } + thread->cpu_context.pc = (unsigned long)ret_from_fork; + thread->cpu_context.sp = (unsigned long)childregs; + + clear_ptrace_hw_breakpoint(p); + + if (clone_flags & CLONE_SETTLS) + thread->tp_value[0] = childregs->ARM_r3; + thread->tp_value[1] = get_tpuser(); + + thread_notify(THREAD_NOTIFY_COPY, thread); + + return 0; +} + +/* + * Fill in the task's elfregs structure for a core dump. + */ +int dump_task_regs(struct task_struct *t, elf_gregset_t *elfregs) +{ + elf_core_copy_regs(elfregs, task_pt_regs(t)); + return 1; +} + +/* + * fill in the fpe structure for a core dump... + */ +int dump_fpu (struct pt_regs *regs, struct user_fp *fp) +{ + struct thread_info *thread = current_thread_info(); + int used_math = thread->used_cp[1] | thread->used_cp[2]; + + if (used_math) + memcpy(fp, &thread->fpstate.soft, sizeof (*fp)); + + return used_math != 0; +} +EXPORT_SYMBOL(dump_fpu); + +unsigned long get_wchan(struct task_struct *p) +{ + struct stackframe frame; + unsigned long stack_page; + int count = 0; + if (!p || p == current || p->state == TASK_RUNNING) + return 0; + + frame.fp = thread_saved_fp(p); + frame.sp = thread_saved_sp(p); + frame.lr = 0; /* recovered from the stack */ + frame.pc = thread_saved_pc(p); + stack_page = (unsigned long)task_stack_page(p); + do { + if (frame.sp < stack_page || + frame.sp >= stack_page + THREAD_SIZE || + unwind_frame(&frame) < 0) + return 0; + if (!in_sched_functions(frame.pc)) + return frame.pc; + } while (count ++ < 16); + return 0; +} + +unsigned long arch_randomize_brk(struct mm_struct *mm) +{ + unsigned long range_end = mm->brk + 0x02000000; + return randomize_range(mm->brk, range_end, 0) ? : mm->brk; +} + +#ifdef CONFIG_MMU +#ifdef CONFIG_KUSER_HELPERS +/* + * The vectors page is always readable from user space for the + * atomic helpers. Insert it into the gate_vma so that it is visible + * through ptrace and /proc//mem. + */ +static struct vm_area_struct gate_vma = { + .vm_start = 0xffff0000, + .vm_end = 0xffff0000 + PAGE_SIZE, + .vm_flags = VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYEXEC, +}; + +static int __init gate_vma_init(void) +{ + gate_vma.vm_page_prot = PAGE_READONLY_EXEC; + return 0; +} +arch_initcall(gate_vma_init); + +struct vm_area_struct *get_gate_vma(struct mm_struct *mm) +{ + return &gate_vma; +} + +int in_gate_area(struct mm_struct *mm, unsigned long addr) +{ + return (addr >= gate_vma.vm_start) && (addr < gate_vma.vm_end); +} + +int in_gate_area_no_mm(unsigned long addr) +{ + return in_gate_area(NULL, addr); +} +#define is_gate_vma(vma) ((vma) == &gate_vma) +#else +#define is_gate_vma(vma) 0 +#endif + +const char *arch_vma_name(struct vm_area_struct *vma) +{ + return is_gate_vma(vma) ? "[vectors]" : NULL; +} + +/* If possible, provide a placement hint at a random offset from the + * stack for the signal page. + */ +static unsigned long sigpage_addr(const struct mm_struct *mm, + unsigned int npages) +{ + unsigned long offset; + unsigned long first; + unsigned long last; + unsigned long addr; + unsigned int slots; + + first = PAGE_ALIGN(mm->start_stack); + + last = TASK_SIZE - (npages << PAGE_SHIFT); + + /* No room after stack? */ + if (first > last) + return 0; + + /* Just enough room? */ + if (first == last) + return first; + + slots = ((last - first) >> PAGE_SHIFT) + 1; + + offset = get_random_int() % slots; + + addr = first + (offset << PAGE_SHIFT); + + return addr; +} + +static struct page *signal_page; +extern struct page *get_signal_page(void); + +static const struct vm_special_mapping sigpage_mapping = { + .name = "[sigpage]", + .pages = &signal_page, +}; + +int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp) +{ + struct mm_struct *mm = current->mm; + struct vm_area_struct *vma; + unsigned long addr; + unsigned long hint; + int ret = 0; + + if (!signal_page) + signal_page = get_signal_page(); + if (!signal_page) + return -ENOMEM; + + down_write(&mm->mmap_sem); + hint = sigpage_addr(mm, 1); + addr = get_unmapped_area(NULL, hint, PAGE_SIZE, 0, 0); + if (IS_ERR_VALUE(addr)) { + ret = addr; + goto up_fail; + } + + vma = _install_special_mapping(mm, addr, PAGE_SIZE, + VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC, + &sigpage_mapping); + + if (IS_ERR(vma)) { + ret = PTR_ERR(vma); + goto up_fail; + } + + mm->context.sigpage = addr; + + up_fail: + up_write(&mm->mmap_sem); + return ret; +} +#endif diff -Nur linux-3.18.14.orig/arch/arm/kernel/signal.c linux-3.18.14-rt/arch/arm/kernel/signal.c --- linux-3.18.14.orig/arch/arm/kernel/signal.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/arm/kernel/signal.c 2015-05-31 15:32:45.617635393 -0500 @@ -574,7 +574,8 @@ do_work_pending(struct pt_regs *regs, unsigned int thread_flags, int syscall) { do { - if (likely(thread_flags & _TIF_NEED_RESCHED)) { + if (likely(thread_flags & (_TIF_NEED_RESCHED | + _TIF_NEED_RESCHED_LAZY))) { schedule(); } else { if (unlikely(!user_mode(regs))) diff -Nur linux-3.18.14.orig/arch/arm/kernel/unwind.c linux-3.18.14-rt/arch/arm/kernel/unwind.c --- linux-3.18.14.orig/arch/arm/kernel/unwind.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/arm/kernel/unwind.c 2015-05-31 15:32:45.653635392 -0500 @@ -93,7 +93,7 @@ static const struct unwind_idx *__origin_unwind_idx; extern const struct unwind_idx __stop_unwind_idx[]; -static DEFINE_SPINLOCK(unwind_lock); +static DEFINE_RAW_SPINLOCK(unwind_lock); static LIST_HEAD(unwind_tables); /* Convert a prel31 symbol to an absolute address */ @@ -201,7 +201,7 @@ /* module unwind tables */ struct unwind_table *table; - spin_lock_irqsave(&unwind_lock, flags); + raw_spin_lock_irqsave(&unwind_lock, flags); list_for_each_entry(table, &unwind_tables, list) { if (addr >= table->begin_addr && addr < table->end_addr) { @@ -213,7 +213,7 @@ break; } } - spin_unlock_irqrestore(&unwind_lock, flags); + raw_spin_unlock_irqrestore(&unwind_lock, flags); } pr_debug("%s: idx = %p\n", __func__, idx); @@ -530,9 +530,9 @@ tab->begin_addr = text_addr; tab->end_addr = text_addr + text_size; - spin_lock_irqsave(&unwind_lock, flags); + raw_spin_lock_irqsave(&unwind_lock, flags); list_add_tail(&tab->list, &unwind_tables); - spin_unlock_irqrestore(&unwind_lock, flags); + raw_spin_unlock_irqrestore(&unwind_lock, flags); return tab; } @@ -544,9 +544,9 @@ if (!tab) return; - spin_lock_irqsave(&unwind_lock, flags); + raw_spin_lock_irqsave(&unwind_lock, flags); list_del(&tab->list); - spin_unlock_irqrestore(&unwind_lock, flags); + raw_spin_unlock_irqrestore(&unwind_lock, flags); kfree(tab); } diff -Nur linux-3.18.14.orig/arch/arm/kvm/arm.c linux-3.18.14-rt/arch/arm/kvm/arm.c --- linux-3.18.14.orig/arch/arm/kvm/arm.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/arm/kvm/arm.c 2015-05-31 15:32:45.669635392 -0500 @@ -455,9 +455,9 @@ static void vcpu_pause(struct kvm_vcpu *vcpu) { - wait_queue_head_t *wq = kvm_arch_vcpu_wq(vcpu); + struct swait_head *wq = kvm_arch_vcpu_wq(vcpu); - wait_event_interruptible(*wq, !vcpu->arch.pause); + swait_event_interruptible(*wq, !vcpu->arch.pause); } static int kvm_vcpu_initialized(struct kvm_vcpu *vcpu) diff -Nur linux-3.18.14.orig/arch/arm/kvm/arm.c.orig linux-3.18.14-rt/arch/arm/kvm/arm.c.orig --- linux-3.18.14.orig/arch/arm/kvm/arm.c.orig 1969-12-31 18:00:00.000000000 -0600 +++ linux-3.18.14-rt/arch/arm/kvm/arm.c.orig 2015-05-20 10:04:50.000000000 -0500 @@ -0,0 +1,1060 @@ +/* + * Copyright (C) 2012 - Virtual Open Systems and Columbia University + * Author: Christoffer Dall + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License, version 2, as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define CREATE_TRACE_POINTS +#include "trace.h" + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#ifdef REQUIRES_VIRT +__asm__(".arch_extension virt"); +#endif + +static DEFINE_PER_CPU(unsigned long, kvm_arm_hyp_stack_page); +static kvm_cpu_context_t __percpu *kvm_host_cpu_state; +static unsigned long hyp_default_vectors; + +/* Per-CPU variable containing the currently running vcpu. */ +static DEFINE_PER_CPU(struct kvm_vcpu *, kvm_arm_running_vcpu); + +/* The VMID used in the VTTBR */ +static atomic64_t kvm_vmid_gen = ATOMIC64_INIT(1); +static u8 kvm_next_vmid; +static DEFINE_SPINLOCK(kvm_vmid_lock); + +static bool vgic_present; + +static void kvm_arm_set_running_vcpu(struct kvm_vcpu *vcpu) +{ + BUG_ON(preemptible()); + __this_cpu_write(kvm_arm_running_vcpu, vcpu); +} + +/** + * kvm_arm_get_running_vcpu - get the vcpu running on the current CPU. + * Must be called from non-preemptible context + */ +struct kvm_vcpu *kvm_arm_get_running_vcpu(void) +{ + BUG_ON(preemptible()); + return __this_cpu_read(kvm_arm_running_vcpu); +} + +/** + * kvm_arm_get_running_vcpus - get the per-CPU array of currently running vcpus. + */ +struct kvm_vcpu * __percpu *kvm_get_running_vcpus(void) +{ + return &kvm_arm_running_vcpu; +} + +int kvm_arch_hardware_enable(void) +{ + return 0; +} + +int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu) +{ + return kvm_vcpu_exiting_guest_mode(vcpu) == IN_GUEST_MODE; +} + +int kvm_arch_hardware_setup(void) +{ + return 0; +} + +void kvm_arch_check_processor_compat(void *rtn) +{ + *(int *)rtn = 0; +} + + +/** + * kvm_arch_init_vm - initializes a VM data structure + * @kvm: pointer to the KVM struct + */ +int kvm_arch_init_vm(struct kvm *kvm, unsigned long type) +{ + int ret = 0; + + if (type) + return -EINVAL; + + ret = kvm_alloc_stage2_pgd(kvm); + if (ret) + goto out_fail_alloc; + + ret = create_hyp_mappings(kvm, kvm + 1); + if (ret) + goto out_free_stage2_pgd; + + kvm_timer_init(kvm); + + /* Mark the initial VMID generation invalid */ + kvm->arch.vmid_gen = 0; + + return ret; +out_free_stage2_pgd: + kvm_free_stage2_pgd(kvm); +out_fail_alloc: + return ret; +} + +int kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf) +{ + return VM_FAULT_SIGBUS; +} + + +/** + * kvm_arch_destroy_vm - destroy the VM data structure + * @kvm: pointer to the KVM struct + */ +void kvm_arch_destroy_vm(struct kvm *kvm) +{ + int i; + + kvm_free_stage2_pgd(kvm); + + for (i = 0; i < KVM_MAX_VCPUS; ++i) { + if (kvm->vcpus[i]) { + kvm_arch_vcpu_free(kvm->vcpus[i]); + kvm->vcpus[i] = NULL; + } + } + + kvm_vgic_destroy(kvm); +} + +int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) +{ + int r; + switch (ext) { + case KVM_CAP_IRQCHIP: + r = vgic_present; + break; + case KVM_CAP_DEVICE_CTRL: + case KVM_CAP_USER_MEMORY: + case KVM_CAP_SYNC_MMU: + case KVM_CAP_DESTROY_MEMORY_REGION_WORKS: + case KVM_CAP_ONE_REG: + case KVM_CAP_ARM_PSCI: + case KVM_CAP_ARM_PSCI_0_2: + case KVM_CAP_READONLY_MEM: + r = 1; + break; + case KVM_CAP_COALESCED_MMIO: + r = KVM_COALESCED_MMIO_PAGE_OFFSET; + break; + case KVM_CAP_ARM_SET_DEVICE_ADDR: + r = 1; + break; + case KVM_CAP_NR_VCPUS: + r = num_online_cpus(); + break; + case KVM_CAP_MAX_VCPUS: + r = KVM_MAX_VCPUS; + break; + default: + r = kvm_arch_dev_ioctl_check_extension(ext); + break; + } + return r; +} + +long kvm_arch_dev_ioctl(struct file *filp, + unsigned int ioctl, unsigned long arg) +{ + return -EINVAL; +} + + +struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm, unsigned int id) +{ + int err; + struct kvm_vcpu *vcpu; + + if (irqchip_in_kernel(kvm) && vgic_initialized(kvm)) { + err = -EBUSY; + goto out; + } + + vcpu = kmem_cache_zalloc(kvm_vcpu_cache, GFP_KERNEL); + if (!vcpu) { + err = -ENOMEM; + goto out; + } + + err = kvm_vcpu_init(vcpu, kvm, id); + if (err) + goto free_vcpu; + + err = create_hyp_mappings(vcpu, vcpu + 1); + if (err) + goto vcpu_uninit; + + return vcpu; +vcpu_uninit: + kvm_vcpu_uninit(vcpu); +free_vcpu: + kmem_cache_free(kvm_vcpu_cache, vcpu); +out: + return ERR_PTR(err); +} + +int kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu) +{ + return 0; +} + +void kvm_arch_vcpu_free(struct kvm_vcpu *vcpu) +{ + kvm_mmu_free_memory_caches(vcpu); + kvm_timer_vcpu_terminate(vcpu); + kvm_vgic_vcpu_destroy(vcpu); + kmem_cache_free(kvm_vcpu_cache, vcpu); +} + +void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu) +{ + kvm_arch_vcpu_free(vcpu); +} + +int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu) +{ + return 0; +} + +int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu) +{ + /* Force users to call KVM_ARM_VCPU_INIT */ + vcpu->arch.target = -1; + + /* Set up the timer */ + kvm_timer_vcpu_init(vcpu); + + return 0; +} + +void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu) +{ + vcpu->cpu = cpu; + vcpu->arch.host_cpu_context = this_cpu_ptr(kvm_host_cpu_state); + + /* + * Check whether this vcpu requires the cache to be flushed on + * this physical CPU. This is a consequence of doing dcache + * operations by set/way on this vcpu. We do it here to be in + * a non-preemptible section. + */ + if (cpumask_test_and_clear_cpu(cpu, &vcpu->arch.require_dcache_flush)) + flush_cache_all(); /* We'd really want v7_flush_dcache_all() */ + + kvm_arm_set_running_vcpu(vcpu); +} + +void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu) +{ + /* + * The arch-generic KVM code expects the cpu field of a vcpu to be -1 + * if the vcpu is no longer assigned to a cpu. This is used for the + * optimized make_all_cpus_request path. + */ + vcpu->cpu = -1; + + kvm_arm_set_running_vcpu(NULL); +} + +int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu, + struct kvm_guest_debug *dbg) +{ + return -EINVAL; +} + + +int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu, + struct kvm_mp_state *mp_state) +{ + return -EINVAL; +} + +int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu, + struct kvm_mp_state *mp_state) +{ + return -EINVAL; +} + +/** + * kvm_arch_vcpu_runnable - determine if the vcpu can be scheduled + * @v: The VCPU pointer + * + * If the guest CPU is not waiting for interrupts or an interrupt line is + * asserted, the CPU is by definition runnable. + */ +int kvm_arch_vcpu_runnable(struct kvm_vcpu *v) +{ + return !!v->arch.irq_lines || kvm_vgic_vcpu_pending_irq(v); +} + +/* Just ensure a guest exit from a particular CPU */ +static void exit_vm_noop(void *info) +{ +} + +void force_vm_exit(const cpumask_t *mask) +{ + smp_call_function_many(mask, exit_vm_noop, NULL, true); +} + +/** + * need_new_vmid_gen - check that the VMID is still valid + * @kvm: The VM's VMID to checkt + * + * return true if there is a new generation of VMIDs being used + * + * The hardware supports only 256 values with the value zero reserved for the + * host, so we check if an assigned value belongs to a previous generation, + * which which requires us to assign a new value. If we're the first to use a + * VMID for the new generation, we must flush necessary caches and TLBs on all + * CPUs. + */ +static bool need_new_vmid_gen(struct kvm *kvm) +{ + return unlikely(kvm->arch.vmid_gen != atomic64_read(&kvm_vmid_gen)); +} + +/** + * update_vttbr - Update the VTTBR with a valid VMID before the guest runs + * @kvm The guest that we are about to run + * + * Called from kvm_arch_vcpu_ioctl_run before entering the guest to ensure the + * VM has a valid VMID, otherwise assigns a new one and flushes corresponding + * caches and TLBs. + */ +static void update_vttbr(struct kvm *kvm) +{ + phys_addr_t pgd_phys; + u64 vmid; + + if (!need_new_vmid_gen(kvm)) + return; + + spin_lock(&kvm_vmid_lock); + + /* + * We need to re-check the vmid_gen here to ensure that if another vcpu + * already allocated a valid vmid for this vm, then this vcpu should + * use the same vmid. + */ + if (!need_new_vmid_gen(kvm)) { + spin_unlock(&kvm_vmid_lock); + return; + } + + /* First user of a new VMID generation? */ + if (unlikely(kvm_next_vmid == 0)) { + atomic64_inc(&kvm_vmid_gen); + kvm_next_vmid = 1; + + /* + * On SMP we know no other CPUs can use this CPU's or each + * other's VMID after force_vm_exit returns since the + * kvm_vmid_lock blocks them from reentry to the guest. + */ + force_vm_exit(cpu_all_mask); + /* + * Now broadcast TLB + ICACHE invalidation over the inner + * shareable domain to make sure all data structures are + * clean. + */ + kvm_call_hyp(__kvm_flush_vm_context); + } + + kvm->arch.vmid_gen = atomic64_read(&kvm_vmid_gen); + kvm->arch.vmid = kvm_next_vmid; + kvm_next_vmid++; + + /* update vttbr to be used with the new vmid */ + pgd_phys = virt_to_phys(kvm_get_hwpgd(kvm)); + BUG_ON(pgd_phys & ~VTTBR_BADDR_MASK); + vmid = ((u64)(kvm->arch.vmid) << VTTBR_VMID_SHIFT) & VTTBR_VMID_MASK; + kvm->arch.vttbr = pgd_phys | vmid; + + spin_unlock(&kvm_vmid_lock); +} + +static int kvm_vcpu_first_run_init(struct kvm_vcpu *vcpu) +{ + struct kvm *kvm = vcpu->kvm; + int ret; + + if (likely(vcpu->arch.has_run_once)) + return 0; + + vcpu->arch.has_run_once = true; + + /* + * Map the VGIC hardware resources before running a vcpu the first + * time on this VM. + */ + if (unlikely(!vgic_initialized(kvm))) { + ret = kvm_vgic_map_resources(kvm); + if (ret) + return ret; + } + + /* + * Enable the arch timers only if we have an in-kernel VGIC + * and it has been properly initialized, since we cannot handle + * interrupts from the virtual timer with a userspace gic. + */ + if (irqchip_in_kernel(kvm) && vgic_initialized(kvm)) + kvm_timer_enable(kvm); + + return 0; +} + +static void vcpu_pause(struct kvm_vcpu *vcpu) +{ + wait_queue_head_t *wq = kvm_arch_vcpu_wq(vcpu); + + wait_event_interruptible(*wq, !vcpu->arch.pause); +} + +static int kvm_vcpu_initialized(struct kvm_vcpu *vcpu) +{ + return vcpu->arch.target >= 0; +} + +/** + * kvm_arch_vcpu_ioctl_run - the main VCPU run function to execute guest code + * @vcpu: The VCPU pointer + * @run: The kvm_run structure pointer used for userspace state exchange + * + * This function is called through the VCPU_RUN ioctl called from user space. It + * will execute VM code in a loop until the time slice for the process is used + * or some emulation is needed from user space in which case the function will + * return with return value 0 and with the kvm_run structure filled in with the + * required data for the requested emulation. + */ +int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run) +{ + int ret; + sigset_t sigsaved; + + if (unlikely(!kvm_vcpu_initialized(vcpu))) + return -ENOEXEC; + + ret = kvm_vcpu_first_run_init(vcpu); + if (ret) + return ret; + + if (run->exit_reason == KVM_EXIT_MMIO) { + ret = kvm_handle_mmio_return(vcpu, vcpu->run); + if (ret) + return ret; + } + + if (vcpu->sigset_active) + sigprocmask(SIG_SETMASK, &vcpu->sigset, &sigsaved); + + ret = 1; + run->exit_reason = KVM_EXIT_UNKNOWN; + while (ret > 0) { + /* + * Check conditions before entering the guest + */ + cond_resched(); + + update_vttbr(vcpu->kvm); + + if (vcpu->arch.pause) + vcpu_pause(vcpu); + + kvm_vgic_flush_hwstate(vcpu); + kvm_timer_flush_hwstate(vcpu); + + local_irq_disable(); + + /* + * Re-check atomic conditions + */ + if (signal_pending(current)) { + ret = -EINTR; + run->exit_reason = KVM_EXIT_INTR; + } + + if (ret <= 0 || need_new_vmid_gen(vcpu->kvm)) { + local_irq_enable(); + kvm_timer_sync_hwstate(vcpu); + kvm_vgic_sync_hwstate(vcpu); + continue; + } + + /************************************************************** + * Enter the guest + */ + trace_kvm_entry(*vcpu_pc(vcpu)); + kvm_guest_enter(); + vcpu->mode = IN_GUEST_MODE; + + ret = kvm_call_hyp(__kvm_vcpu_run, vcpu); + + vcpu->mode = OUTSIDE_GUEST_MODE; + vcpu->arch.last_pcpu = smp_processor_id(); + kvm_guest_exit(); + trace_kvm_exit(*vcpu_pc(vcpu)); + /* + * We may have taken a host interrupt in HYP mode (ie + * while executing the guest). This interrupt is still + * pending, as we haven't serviced it yet! + * + * We're now back in SVC mode, with interrupts + * disabled. Enabling the interrupts now will have + * the effect of taking the interrupt again, in SVC + * mode this time. + */ + local_irq_enable(); + + /* + * Back from guest + *************************************************************/ + + kvm_timer_sync_hwstate(vcpu); + kvm_vgic_sync_hwstate(vcpu); + + ret = handle_exit(vcpu, run, ret); + } + + if (vcpu->sigset_active) + sigprocmask(SIG_SETMASK, &sigsaved, NULL); + return ret; +} + +static int vcpu_interrupt_line(struct kvm_vcpu *vcpu, int number, bool level) +{ + int bit_index; + bool set; + unsigned long *ptr; + + if (number == KVM_ARM_IRQ_CPU_IRQ) + bit_index = __ffs(HCR_VI); + else /* KVM_ARM_IRQ_CPU_FIQ */ + bit_index = __ffs(HCR_VF); + + ptr = (unsigned long *)&vcpu->arch.irq_lines; + if (level) + set = test_and_set_bit(bit_index, ptr); + else + set = test_and_clear_bit(bit_index, ptr); + + /* + * If we didn't change anything, no need to wake up or kick other CPUs + */ + if (set == level) + return 0; + + /* + * The vcpu irq_lines field was updated, wake up sleeping VCPUs and + * trigger a world-switch round on the running physical CPU to set the + * virtual IRQ/FIQ fields in the HCR appropriately. + */ + kvm_vcpu_kick(vcpu); + + return 0; +} + +int kvm_vm_ioctl_irq_line(struct kvm *kvm, struct kvm_irq_level *irq_level, + bool line_status) +{ + u32 irq = irq_level->irq; + unsigned int irq_type, vcpu_idx, irq_num; + int nrcpus = atomic_read(&kvm->online_vcpus); + struct kvm_vcpu *vcpu = NULL; + bool level = irq_level->level; + + irq_type = (irq >> KVM_ARM_IRQ_TYPE_SHIFT) & KVM_ARM_IRQ_TYPE_MASK; + vcpu_idx = (irq >> KVM_ARM_IRQ_VCPU_SHIFT) & KVM_ARM_IRQ_VCPU_MASK; + irq_num = (irq >> KVM_ARM_IRQ_NUM_SHIFT) & KVM_ARM_IRQ_NUM_MASK; + + trace_kvm_irq_line(irq_type, vcpu_idx, irq_num, irq_level->level); + + switch (irq_type) { + case KVM_ARM_IRQ_TYPE_CPU: + if (irqchip_in_kernel(kvm)) + return -ENXIO; + + if (vcpu_idx >= nrcpus) + return -EINVAL; + + vcpu = kvm_get_vcpu(kvm, vcpu_idx); + if (!vcpu) + return -EINVAL; + + if (irq_num > KVM_ARM_IRQ_CPU_FIQ) + return -EINVAL; + + return vcpu_interrupt_line(vcpu, irq_num, level); + case KVM_ARM_IRQ_TYPE_PPI: + if (!irqchip_in_kernel(kvm)) + return -ENXIO; + + if (vcpu_idx >= nrcpus) + return -EINVAL; + + vcpu = kvm_get_vcpu(kvm, vcpu_idx); + if (!vcpu) + return -EINVAL; + + if (irq_num < VGIC_NR_SGIS || irq_num >= VGIC_NR_PRIVATE_IRQS) + return -EINVAL; + + return kvm_vgic_inject_irq(kvm, vcpu->vcpu_id, irq_num, level); + case KVM_ARM_IRQ_TYPE_SPI: + if (!irqchip_in_kernel(kvm)) + return -ENXIO; + + if (irq_num < VGIC_NR_PRIVATE_IRQS) + return -EINVAL; + + return kvm_vgic_inject_irq(kvm, 0, irq_num, level); + } + + return -EINVAL; +} + +static int kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu *vcpu, + struct kvm_vcpu_init *init) +{ + int ret; + + ret = kvm_vcpu_set_target(vcpu, init); + if (ret) + return ret; + + /* + * Ensure a rebooted VM will fault in RAM pages and detect if the + * guest MMU is turned off and flush the caches as needed. + */ + if (vcpu->arch.has_run_once) + stage2_unmap_vm(vcpu->kvm); + + vcpu_reset_hcr(vcpu); + + /* + * Handle the "start in power-off" case by marking the VCPU as paused. + */ + if (test_bit(KVM_ARM_VCPU_POWER_OFF, vcpu->arch.features)) + vcpu->arch.pause = true; + else + vcpu->arch.pause = false; + + return 0; +} + +long kvm_arch_vcpu_ioctl(struct file *filp, + unsigned int ioctl, unsigned long arg) +{ + struct kvm_vcpu *vcpu = filp->private_data; + void __user *argp = (void __user *)arg; + + switch (ioctl) { + case KVM_ARM_VCPU_INIT: { + struct kvm_vcpu_init init; + + if (copy_from_user(&init, argp, sizeof(init))) + return -EFAULT; + + return kvm_arch_vcpu_ioctl_vcpu_init(vcpu, &init); + } + case KVM_SET_ONE_REG: + case KVM_GET_ONE_REG: { + struct kvm_one_reg reg; + + if (unlikely(!kvm_vcpu_initialized(vcpu))) + return -ENOEXEC; + + if (copy_from_user(®, argp, sizeof(reg))) + return -EFAULT; + if (ioctl == KVM_SET_ONE_REG) + return kvm_arm_set_reg(vcpu, ®); + else + return kvm_arm_get_reg(vcpu, ®); + } + case KVM_GET_REG_LIST: { + struct kvm_reg_list __user *user_list = argp; + struct kvm_reg_list reg_list; + unsigned n; + + if (unlikely(!kvm_vcpu_initialized(vcpu))) + return -ENOEXEC; + + if (copy_from_user(®_list, user_list, sizeof(reg_list))) + return -EFAULT; + n = reg_list.n; + reg_list.n = kvm_arm_num_regs(vcpu); + if (copy_to_user(user_list, ®_list, sizeof(reg_list))) + return -EFAULT; + if (n < reg_list.n) + return -E2BIG; + return kvm_arm_copy_reg_indices(vcpu, user_list->reg); + } + default: + return -EINVAL; + } +} + +int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm, struct kvm_dirty_log *log) +{ + return -EINVAL; +} + +static int kvm_vm_ioctl_set_device_addr(struct kvm *kvm, + struct kvm_arm_device_addr *dev_addr) +{ + unsigned long dev_id, type; + + dev_id = (dev_addr->id & KVM_ARM_DEVICE_ID_MASK) >> + KVM_ARM_DEVICE_ID_SHIFT; + type = (dev_addr->id & KVM_ARM_DEVICE_TYPE_MASK) >> + KVM_ARM_DEVICE_TYPE_SHIFT; + + switch (dev_id) { + case KVM_ARM_DEVICE_VGIC_V2: + if (!vgic_present) + return -ENXIO; + return kvm_vgic_addr(kvm, type, &dev_addr->addr, true); + default: + return -ENODEV; + } +} + +long kvm_arch_vm_ioctl(struct file *filp, + unsigned int ioctl, unsigned long arg) +{ + struct kvm *kvm = filp->private_data; + void __user *argp = (void __user *)arg; + + switch (ioctl) { + case KVM_CREATE_IRQCHIP: { + if (vgic_present) + return kvm_vgic_create(kvm); + else + return -ENXIO; + } + case KVM_ARM_SET_DEVICE_ADDR: { + struct kvm_arm_device_addr dev_addr; + + if (copy_from_user(&dev_addr, argp, sizeof(dev_addr))) + return -EFAULT; + return kvm_vm_ioctl_set_device_addr(kvm, &dev_addr); + } + case KVM_ARM_PREFERRED_TARGET: { + int err; + struct kvm_vcpu_init init; + + err = kvm_vcpu_preferred_target(&init); + if (err) + return err; + + if (copy_to_user(argp, &init, sizeof(init))) + return -EFAULT; + + return 0; + } + default: + return -EINVAL; + } +} + +static void cpu_init_hyp_mode(void *dummy) +{ + phys_addr_t boot_pgd_ptr; + phys_addr_t pgd_ptr; + unsigned long hyp_stack_ptr; + unsigned long stack_page; + unsigned long vector_ptr; + + /* Switch from the HYP stub to our own HYP init vector */ + __hyp_set_vectors(kvm_get_idmap_vector()); + + boot_pgd_ptr = kvm_mmu_get_boot_httbr(); + pgd_ptr = kvm_mmu_get_httbr(); + stack_page = __this_cpu_read(kvm_arm_hyp_stack_page); + hyp_stack_ptr = stack_page + PAGE_SIZE; + vector_ptr = (unsigned long)__kvm_hyp_vector; + + __cpu_init_hyp_mode(boot_pgd_ptr, pgd_ptr, hyp_stack_ptr, vector_ptr); +} + +static int hyp_init_cpu_notify(struct notifier_block *self, + unsigned long action, void *cpu) +{ + switch (action) { + case CPU_STARTING: + case CPU_STARTING_FROZEN: + if (__hyp_get_vectors() == hyp_default_vectors) + cpu_init_hyp_mode(NULL); + break; + } + + return NOTIFY_OK; +} + +static struct notifier_block hyp_init_cpu_nb = { + .notifier_call = hyp_init_cpu_notify, +}; + +#ifdef CONFIG_CPU_PM +static int hyp_init_cpu_pm_notifier(struct notifier_block *self, + unsigned long cmd, + void *v) +{ + if (cmd == CPU_PM_EXIT && + __hyp_get_vectors() == hyp_default_vectors) { + cpu_init_hyp_mode(NULL); + return NOTIFY_OK; + } + + return NOTIFY_DONE; +} + +static struct notifier_block hyp_init_cpu_pm_nb = { + .notifier_call = hyp_init_cpu_pm_notifier, +}; + +static void __init hyp_cpu_pm_init(void) +{ + cpu_pm_register_notifier(&hyp_init_cpu_pm_nb); +} +#else +static inline void hyp_cpu_pm_init(void) +{ +} +#endif + +/** + * Inits Hyp-mode on all online CPUs + */ +static int init_hyp_mode(void) +{ + int cpu; + int err = 0; + + /* + * Allocate Hyp PGD and setup Hyp identity mapping + */ + err = kvm_mmu_init(); + if (err) + goto out_err; + + /* + * It is probably enough to obtain the default on one + * CPU. It's unlikely to be different on the others. + */ + hyp_default_vectors = __hyp_get_vectors(); + + /* + * Allocate stack pages for Hypervisor-mode + */ + for_each_possible_cpu(cpu) { + unsigned long stack_page; + + stack_page = __get_free_page(GFP_KERNEL); + if (!stack_page) { + err = -ENOMEM; + goto out_free_stack_pages; + } + + per_cpu(kvm_arm_hyp_stack_page, cpu) = stack_page; + } + + /* + * Map the Hyp-code called directly from the host + */ + err = create_hyp_mappings(__kvm_hyp_code_start, __kvm_hyp_code_end); + if (err) { + kvm_err("Cannot map world-switch code\n"); + goto out_free_mappings; + } + + /* + * Map the Hyp stack pages + */ + for_each_possible_cpu(cpu) { + char *stack_page = (char *)per_cpu(kvm_arm_hyp_stack_page, cpu); + err = create_hyp_mappings(stack_page, stack_page + PAGE_SIZE); + + if (err) { + kvm_err("Cannot map hyp stack\n"); + goto out_free_mappings; + } + } + + /* + * Map the host CPU structures + */ + kvm_host_cpu_state = alloc_percpu(kvm_cpu_context_t); + if (!kvm_host_cpu_state) { + err = -ENOMEM; + kvm_err("Cannot allocate host CPU state\n"); + goto out_free_mappings; + } + + for_each_possible_cpu(cpu) { + kvm_cpu_context_t *cpu_ctxt; + + cpu_ctxt = per_cpu_ptr(kvm_host_cpu_state, cpu); + err = create_hyp_mappings(cpu_ctxt, cpu_ctxt + 1); + + if (err) { + kvm_err("Cannot map host CPU state: %d\n", err); + goto out_free_context; + } + } + + /* + * Execute the init code on each CPU. + */ + on_each_cpu(cpu_init_hyp_mode, NULL, 1); + + /* + * Init HYP view of VGIC + */ + err = kvm_vgic_hyp_init(); + if (err) + goto out_free_context; + +#ifdef CONFIG_KVM_ARM_VGIC + vgic_present = true; +#endif + + /* + * Init HYP architected timer support + */ + err = kvm_timer_hyp_init(); + if (err) + goto out_free_mappings; + +#ifndef CONFIG_HOTPLUG_CPU + free_boot_hyp_pgd(); +#endif + + kvm_perf_init(); + + kvm_info("Hyp mode initialized successfully\n"); + + return 0; +out_free_context: + free_percpu(kvm_host_cpu_state); +out_free_mappings: + free_hyp_pgds(); +out_free_stack_pages: + for_each_possible_cpu(cpu) + free_page(per_cpu(kvm_arm_hyp_stack_page, cpu)); +out_err: + kvm_err("error initializing Hyp mode: %d\n", err); + return err; +} + +static void check_kvm_target_cpu(void *ret) +{ + *(int *)ret = kvm_target_cpu(); +} + +/** + * Initialize Hyp-mode and memory mappings on all CPUs. + */ +int kvm_arch_init(void *opaque) +{ + int err; + int ret, cpu; + + if (!is_hyp_mode_available()) { + kvm_err("HYP mode not available\n"); + return -ENODEV; + } + + for_each_online_cpu(cpu) { + smp_call_function_single(cpu, check_kvm_target_cpu, &ret, 1); + if (ret < 0) { + kvm_err("Error, CPU %d not supported!\n", cpu); + return -ENODEV; + } + } + + cpu_notifier_register_begin(); + + err = init_hyp_mode(); + if (err) + goto out_err; + + err = __register_cpu_notifier(&hyp_init_cpu_nb); + if (err) { + kvm_err("Cannot register HYP init CPU notifier (%d)\n", err); + goto out_err; + } + + cpu_notifier_register_done(); + + hyp_cpu_pm_init(); + + kvm_coproc_table_init(); + return 0; +out_err: + cpu_notifier_register_done(); + return err; +} + +/* NOP: Compiling as a module not supported */ +void kvm_arch_exit(void) +{ + kvm_perf_teardown(); +} + +static int arm_init(void) +{ + int rc = kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE); + return rc; +} + +module_init(arm_init); diff -Nur linux-3.18.14.orig/arch/arm/kvm/psci.c linux-3.18.14-rt/arch/arm/kvm/psci.c --- linux-3.18.14.orig/arch/arm/kvm/psci.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/arm/kvm/psci.c 2015-05-31 15:32:45.673635392 -0500 @@ -67,7 +67,7 @@ { struct kvm *kvm = source_vcpu->kvm; struct kvm_vcpu *vcpu = NULL, *tmp; - wait_queue_head_t *wq; + struct swait_head *wq; unsigned long cpu_id; unsigned long context_id; unsigned long mpidr; @@ -124,7 +124,7 @@ smp_mb(); /* Make sure the above is visible */ wq = kvm_arch_vcpu_wq(vcpu); - wake_up_interruptible(wq); + swait_wake_interruptible(wq); return PSCI_RET_SUCCESS; } diff -Nur linux-3.18.14.orig/arch/arm/kvm/psci.c.orig linux-3.18.14-rt/arch/arm/kvm/psci.c.orig --- linux-3.18.14.orig/arch/arm/kvm/psci.c.orig 1969-12-31 18:00:00.000000000 -0600 +++ linux-3.18.14-rt/arch/arm/kvm/psci.c.orig 2015-05-20 10:04:50.000000000 -0500 @@ -0,0 +1,337 @@ +/* + * Copyright (C) 2012 - ARM Ltd + * Author: Marc Zyngier + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see . + */ + +#include +#include +#include + +#include +#include +#include + +/* + * This is an implementation of the Power State Coordination Interface + * as described in ARM document number ARM DEN 0022A. + */ + +#define AFFINITY_MASK(level) ~((0x1UL << ((level) * MPIDR_LEVEL_BITS)) - 1) + +static unsigned long psci_affinity_mask(unsigned long affinity_level) +{ + if (affinity_level <= 3) + return MPIDR_HWID_BITMASK & AFFINITY_MASK(affinity_level); + + return 0; +} + +static unsigned long kvm_psci_vcpu_suspend(struct kvm_vcpu *vcpu) +{ + /* + * NOTE: For simplicity, we make VCPU suspend emulation to be + * same-as WFI (Wait-for-interrupt) emulation. + * + * This means for KVM the wakeup events are interrupts and + * this is consistent with intended use of StateID as described + * in section 5.4.1 of PSCI v0.2 specification (ARM DEN 0022A). + * + * Further, we also treat power-down request to be same as + * stand-by request as-per section 5.4.2 clause 3 of PSCI v0.2 + * specification (ARM DEN 0022A). This means all suspend states + * for KVM will preserve the register state. + */ + kvm_vcpu_block(vcpu); + + return PSCI_RET_SUCCESS; +} + +static void kvm_psci_vcpu_off(struct kvm_vcpu *vcpu) +{ + vcpu->arch.pause = true; +} + +static unsigned long kvm_psci_vcpu_on(struct kvm_vcpu *source_vcpu) +{ + struct kvm *kvm = source_vcpu->kvm; + struct kvm_vcpu *vcpu = NULL, *tmp; + wait_queue_head_t *wq; + unsigned long cpu_id; + unsigned long context_id; + unsigned long mpidr; + phys_addr_t target_pc; + int i; + + cpu_id = *vcpu_reg(source_vcpu, 1); + if (vcpu_mode_is_32bit(source_vcpu)) + cpu_id &= ~((u32) 0); + + kvm_for_each_vcpu(i, tmp, kvm) { + mpidr = kvm_vcpu_get_mpidr(tmp); + if ((mpidr & MPIDR_HWID_BITMASK) == (cpu_id & MPIDR_HWID_BITMASK)) { + vcpu = tmp; + break; + } + } + + /* + * Make sure the caller requested a valid CPU and that the CPU is + * turned off. + */ + if (!vcpu) + return PSCI_RET_INVALID_PARAMS; + if (!vcpu->arch.pause) { + if (kvm_psci_version(source_vcpu) != KVM_ARM_PSCI_0_1) + return PSCI_RET_ALREADY_ON; + else + return PSCI_RET_INVALID_PARAMS; + } + + target_pc = *vcpu_reg(source_vcpu, 2); + context_id = *vcpu_reg(source_vcpu, 3); + + kvm_reset_vcpu(vcpu); + + /* Gracefully handle Thumb2 entry point */ + if (vcpu_mode_is_32bit(vcpu) && (target_pc & 1)) { + target_pc &= ~((phys_addr_t) 1); + vcpu_set_thumb(vcpu); + } + + /* Propagate caller endianness */ + if (kvm_vcpu_is_be(source_vcpu)) + kvm_vcpu_set_be(vcpu); + + *vcpu_pc(vcpu) = target_pc; + /* + * NOTE: We always update r0 (or x0) because for PSCI v0.1 + * the general puspose registers are undefined upon CPU_ON. + */ + *vcpu_reg(vcpu, 0) = context_id; + vcpu->arch.pause = false; + smp_mb(); /* Make sure the above is visible */ + + wq = kvm_arch_vcpu_wq(vcpu); + wake_up_interruptible(wq); + + return PSCI_RET_SUCCESS; +} + +static unsigned long kvm_psci_vcpu_affinity_info(struct kvm_vcpu *vcpu) +{ + int i; + unsigned long mpidr; + unsigned long target_affinity; + unsigned long target_affinity_mask; + unsigned long lowest_affinity_level; + struct kvm *kvm = vcpu->kvm; + struct kvm_vcpu *tmp; + + target_affinity = *vcpu_reg(vcpu, 1); + lowest_affinity_level = *vcpu_reg(vcpu, 2); + + /* Determine target affinity mask */ + target_affinity_mask = psci_affinity_mask(lowest_affinity_level); + if (!target_affinity_mask) + return PSCI_RET_INVALID_PARAMS; + + /* Ignore other bits of target affinity */ + target_affinity &= target_affinity_mask; + + /* + * If one or more VCPU matching target affinity are running + * then ON else OFF + */ + kvm_for_each_vcpu(i, tmp, kvm) { + mpidr = kvm_vcpu_get_mpidr(tmp); + if (((mpidr & target_affinity_mask) == target_affinity) && + !tmp->arch.pause) { + return PSCI_0_2_AFFINITY_LEVEL_ON; + } + } + + return PSCI_0_2_AFFINITY_LEVEL_OFF; +} + +static void kvm_prepare_system_event(struct kvm_vcpu *vcpu, u32 type) +{ + int i; + struct kvm_vcpu *tmp; + + /* + * The KVM ABI specifies that a system event exit may call KVM_RUN + * again and may perform shutdown/reboot at a later time that when the + * actual request is made. Since we are implementing PSCI and a + * caller of PSCI reboot and shutdown expects that the system shuts + * down or reboots immediately, let's make sure that VCPUs are not run + * after this call is handled and before the VCPUs have been + * re-initialized. + */ + kvm_for_each_vcpu(i, tmp, vcpu->kvm) { + tmp->arch.pause = true; + kvm_vcpu_kick(tmp); + } + + memset(&vcpu->run->system_event, 0, sizeof(vcpu->run->system_event)); + vcpu->run->system_event.type = type; + vcpu->run->exit_reason = KVM_EXIT_SYSTEM_EVENT; +} + +static void kvm_psci_system_off(struct kvm_vcpu *vcpu) +{ + kvm_prepare_system_event(vcpu, KVM_SYSTEM_EVENT_SHUTDOWN); +} + +static void kvm_psci_system_reset(struct kvm_vcpu *vcpu) +{ + kvm_prepare_system_event(vcpu, KVM_SYSTEM_EVENT_RESET); +} + +int kvm_psci_version(struct kvm_vcpu *vcpu) +{ + if (test_bit(KVM_ARM_VCPU_PSCI_0_2, vcpu->arch.features)) + return KVM_ARM_PSCI_0_2; + + return KVM_ARM_PSCI_0_1; +} + +static int kvm_psci_0_2_call(struct kvm_vcpu *vcpu) +{ + int ret = 1; + unsigned long psci_fn = *vcpu_reg(vcpu, 0) & ~((u32) 0); + unsigned long val; + + switch (psci_fn) { + case PSCI_0_2_FN_PSCI_VERSION: + /* + * Bits[31:16] = Major Version = 0 + * Bits[15:0] = Minor Version = 2 + */ + val = 2; + break; + case PSCI_0_2_FN_CPU_SUSPEND: + case PSCI_0_2_FN64_CPU_SUSPEND: + val = kvm_psci_vcpu_suspend(vcpu); + break; + case PSCI_0_2_FN_CPU_OFF: + kvm_psci_vcpu_off(vcpu); + val = PSCI_RET_SUCCESS; + break; + case PSCI_0_2_FN_CPU_ON: + case PSCI_0_2_FN64_CPU_ON: + val = kvm_psci_vcpu_on(vcpu); + break; + case PSCI_0_2_FN_AFFINITY_INFO: + case PSCI_0_2_FN64_AFFINITY_INFO: + val = kvm_psci_vcpu_affinity_info(vcpu); + break; + case PSCI_0_2_FN_MIGRATE: + case PSCI_0_2_FN64_MIGRATE: + val = PSCI_RET_NOT_SUPPORTED; + break; + case PSCI_0_2_FN_MIGRATE_INFO_TYPE: + /* + * Trusted OS is MP hence does not require migration + * or + * Trusted OS is not present + */ + val = PSCI_0_2_TOS_MP; + break; + case PSCI_0_2_FN_MIGRATE_INFO_UP_CPU: + case PSCI_0_2_FN64_MIGRATE_INFO_UP_CPU: + val = PSCI_RET_NOT_SUPPORTED; + break; + case PSCI_0_2_FN_SYSTEM_OFF: + kvm_psci_system_off(vcpu); + /* + * We should'nt be going back to guest VCPU after + * receiving SYSTEM_OFF request. + * + * If user space accidently/deliberately resumes + * guest VCPU after SYSTEM_OFF request then guest + * VCPU should see internal failure from PSCI return + * value. To achieve this, we preload r0 (or x0) with + * PSCI return value INTERNAL_FAILURE. + */ + val = PSCI_RET_INTERNAL_FAILURE; + ret = 0; + break; + case PSCI_0_2_FN_SYSTEM_RESET: + kvm_psci_system_reset(vcpu); + /* + * Same reason as SYSTEM_OFF for preloading r0 (or x0) + * with PSCI return value INTERNAL_FAILURE. + */ + val = PSCI_RET_INTERNAL_FAILURE; + ret = 0; + break; + default: + return -EINVAL; + } + + *vcpu_reg(vcpu, 0) = val; + return ret; +} + +static int kvm_psci_0_1_call(struct kvm_vcpu *vcpu) +{ + unsigned long psci_fn = *vcpu_reg(vcpu, 0) & ~((u32) 0); + unsigned long val; + + switch (psci_fn) { + case KVM_PSCI_FN_CPU_OFF: + kvm_psci_vcpu_off(vcpu); + val = PSCI_RET_SUCCESS; + break; + case KVM_PSCI_FN_CPU_ON: + val = kvm_psci_vcpu_on(vcpu); + break; + case KVM_PSCI_FN_CPU_SUSPEND: + case KVM_PSCI_FN_MIGRATE: + val = PSCI_RET_NOT_SUPPORTED; + break; + default: + return -EINVAL; + } + + *vcpu_reg(vcpu, 0) = val; + return 1; +} + +/** + * kvm_psci_call - handle PSCI call if r0 value is in range + * @vcpu: Pointer to the VCPU struct + * + * Handle PSCI calls from guests through traps from HVC instructions. + * The calling convention is similar to SMC calls to the secure world + * where the function number is placed in r0. + * + * This function returns: > 0 (success), 0 (success but exit to user + * space), and < 0 (errors) + * + * Errors: + * -EINVAL: Unrecognized PSCI function + */ +int kvm_psci_call(struct kvm_vcpu *vcpu) +{ + switch (kvm_psci_version(vcpu)) { + case KVM_ARM_PSCI_0_2: + return kvm_psci_0_2_call(vcpu); + case KVM_ARM_PSCI_0_1: + return kvm_psci_0_1_call(vcpu); + default: + return -EINVAL; + }; +} diff -Nur linux-3.18.14.orig/arch/arm/mach-at91/at91rm9200_time.c linux-3.18.14-rt/arch/arm/mach-at91/at91rm9200_time.c --- linux-3.18.14.orig/arch/arm/mach-at91/at91rm9200_time.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/arm/mach-at91/at91rm9200_time.c 2015-05-31 15:32:45.673635392 -0500 @@ -135,6 +135,7 @@ break; case CLOCK_EVT_MODE_SHUTDOWN: case CLOCK_EVT_MODE_UNUSED: + remove_irq(NR_IRQS_LEGACY + AT91_ID_SYS, &at91rm9200_timer_irq); case CLOCK_EVT_MODE_RESUME: irqmask = 0; break; diff -Nur linux-3.18.14.orig/arch/arm/mach-exynos/platsmp.c linux-3.18.14-rt/arch/arm/mach-exynos/platsmp.c --- linux-3.18.14.orig/arch/arm/mach-exynos/platsmp.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/arm/mach-exynos/platsmp.c 2015-05-31 15:32:45.673635392 -0500 @@ -137,7 +137,7 @@ return (void __iomem *)(S5P_VA_SCU); } -static DEFINE_SPINLOCK(boot_lock); +static DEFINE_RAW_SPINLOCK(boot_lock); static void exynos_secondary_init(unsigned int cpu) { @@ -150,8 +150,8 @@ /* * Synchronise with the boot thread. */ - spin_lock(&boot_lock); - spin_unlock(&boot_lock); + raw_spin_lock(&boot_lock); + raw_spin_unlock(&boot_lock); } static int exynos_boot_secondary(unsigned int cpu, struct task_struct *idle) @@ -165,7 +165,7 @@ * Set synchronisation state between this boot processor * and the secondary one */ - spin_lock(&boot_lock); + raw_spin_lock(&boot_lock); /* * The secondary processor is waiting to be released from @@ -192,7 +192,7 @@ if (timeout == 0) { printk(KERN_ERR "cpu1 power enable failed"); - spin_unlock(&boot_lock); + raw_spin_unlock(&boot_lock); return -ETIMEDOUT; } } @@ -242,7 +242,7 @@ * calibrations, then wait for it to finish */ fail: - spin_unlock(&boot_lock); + raw_spin_unlock(&boot_lock); return pen_release != -1 ? ret : 0; } diff -Nur linux-3.18.14.orig/arch/arm/mach-hisi/platmcpm.c linux-3.18.14-rt/arch/arm/mach-hisi/platmcpm.c --- linux-3.18.14.orig/arch/arm/mach-hisi/platmcpm.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/arm/mach-hisi/platmcpm.c 2015-05-31 15:32:45.677635392 -0500 @@ -57,7 +57,7 @@ static void __iomem *sysctrl, *fabric; static int hip04_cpu_table[HIP04_MAX_CLUSTERS][HIP04_MAX_CPUS_PER_CLUSTER]; -static DEFINE_SPINLOCK(boot_lock); +static DEFINE_RAW_SPINLOCK(boot_lock); static u32 fabric_phys_addr; /* * [0]: bootwrapper physical address @@ -104,7 +104,7 @@ if (cluster >= HIP04_MAX_CLUSTERS || cpu >= HIP04_MAX_CPUS_PER_CLUSTER) return -EINVAL; - spin_lock_irq(&boot_lock); + raw_spin_lock_irq(&boot_lock); if (hip04_cpu_table[cluster][cpu]) goto out; @@ -133,7 +133,7 @@ udelay(20); out: hip04_cpu_table[cluster][cpu]++; - spin_unlock_irq(&boot_lock); + raw_spin_unlock_irq(&boot_lock); return 0; } @@ -149,7 +149,7 @@ __mcpm_cpu_going_down(cpu, cluster); - spin_lock(&boot_lock); + raw_spin_lock(&boot_lock); BUG_ON(__mcpm_cluster_state(cluster) != CLUSTER_UP); hip04_cpu_table[cluster][cpu]--; if (hip04_cpu_table[cluster][cpu] == 1) { @@ -162,7 +162,7 @@ last_man = hip04_cluster_is_down(cluster); if (last_man && __mcpm_outbound_enter_critical(cpu, cluster)) { - spin_unlock(&boot_lock); + raw_spin_unlock(&boot_lock); /* Since it's Cortex A15, disable L2 prefetching. */ asm volatile( "mcr p15, 1, %0, c15, c0, 3 \n\t" @@ -173,7 +173,7 @@ hip04_set_snoop_filter(cluster, 0); __mcpm_outbound_leave_critical(cluster, CLUSTER_DOWN); } else { - spin_unlock(&boot_lock); + raw_spin_unlock(&boot_lock); v7_exit_coherency_flush(louis); } @@ -192,7 +192,7 @@ cpu >= HIP04_MAX_CPUS_PER_CLUSTER); count = TIMEOUT_MSEC / POLL_MSEC; - spin_lock_irq(&boot_lock); + raw_spin_lock_irq(&boot_lock); for (tries = 0; tries < count; tries++) { if (hip04_cpu_table[cluster][cpu]) { ret = -EBUSY; @@ -202,10 +202,10 @@ data = readl_relaxed(sysctrl + SC_CPU_RESET_STATUS(cluster)); if (data & CORE_WFI_STATUS(cpu)) break; - spin_unlock_irq(&boot_lock); + raw_spin_unlock_irq(&boot_lock); /* Wait for clean L2 when the whole cluster is down. */ msleep(POLL_MSEC); - spin_lock_irq(&boot_lock); + raw_spin_lock_irq(&boot_lock); } if (tries >= count) goto err; @@ -220,10 +220,10 @@ } if (tries >= count) goto err; - spin_unlock_irq(&boot_lock); + raw_spin_unlock_irq(&boot_lock); return 0; err: - spin_unlock_irq(&boot_lock); + raw_spin_unlock_irq(&boot_lock); return ret; } @@ -235,10 +235,10 @@ cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0); cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1); - spin_lock(&boot_lock); + raw_spin_lock(&boot_lock); if (!hip04_cpu_table[cluster][cpu]) hip04_cpu_table[cluster][cpu] = 1; - spin_unlock(&boot_lock); + raw_spin_unlock(&boot_lock); } static void __naked hip04_mcpm_power_up_setup(unsigned int affinity_level) diff -Nur linux-3.18.14.orig/arch/arm/mach-omap2/omap-smp.c linux-3.18.14-rt/arch/arm/mach-omap2/omap-smp.c --- linux-3.18.14.orig/arch/arm/mach-omap2/omap-smp.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/arm/mach-omap2/omap-smp.c 2015-05-31 15:32:45.697635392 -0500 @@ -43,7 +43,7 @@ /* SCU base address */ static void __iomem *scu_base; -static DEFINE_SPINLOCK(boot_lock); +static DEFINE_RAW_SPINLOCK(boot_lock); void __iomem *omap4_get_scu_base(void) { @@ -74,8 +74,8 @@ /* * Synchronise with the boot thread. */ - spin_lock(&boot_lock); - spin_unlock(&boot_lock); + raw_spin_lock(&boot_lock); + raw_spin_unlock(&boot_lock); } static int omap4_boot_secondary(unsigned int cpu, struct task_struct *idle) @@ -89,7 +89,7 @@ * Set synchronisation state between this boot processor * and the secondary one */ - spin_lock(&boot_lock); + raw_spin_lock(&boot_lock); /* * Update the AuxCoreBoot0 with boot state for secondary core. @@ -166,7 +166,7 @@ * Now the secondary core is starting up let it run its * calibrations, then wait for it to finish */ - spin_unlock(&boot_lock); + raw_spin_unlock(&boot_lock); return 0; } diff -Nur linux-3.18.14.orig/arch/arm/mach-prima2/platsmp.c linux-3.18.14-rt/arch/arm/mach-prima2/platsmp.c --- linux-3.18.14.orig/arch/arm/mach-prima2/platsmp.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/arm/mach-prima2/platsmp.c 2015-05-31 15:32:45.721635392 -0500 @@ -23,7 +23,7 @@ static void __iomem *scu_base; static void __iomem *rsc_base; -static DEFINE_SPINLOCK(boot_lock); +static DEFINE_RAW_SPINLOCK(boot_lock); static struct map_desc scu_io_desc __initdata = { .length = SZ_4K, @@ -56,8 +56,8 @@ /* * Synchronise with the boot thread. */ - spin_lock(&boot_lock); - spin_unlock(&boot_lock); + raw_spin_lock(&boot_lock); + raw_spin_unlock(&boot_lock); } static struct of_device_id rsc_ids[] = { @@ -95,7 +95,7 @@ /* make sure write buffer is drained */ mb(); - spin_lock(&boot_lock); + raw_spin_lock(&boot_lock); /* * The secondary processor is waiting to be released from @@ -127,7 +127,7 @@ * now the secondary core is starting up let it run its * calibrations, then wait for it to finish */ - spin_unlock(&boot_lock); + raw_spin_unlock(&boot_lock); return pen_release != -1 ? -ENOSYS : 0; } diff -Nur linux-3.18.14.orig/arch/arm/mach-qcom/platsmp.c linux-3.18.14-rt/arch/arm/mach-qcom/platsmp.c --- linux-3.18.14.orig/arch/arm/mach-qcom/platsmp.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/arm/mach-qcom/platsmp.c 2015-05-31 15:32:45.741635391 -0500 @@ -46,7 +46,7 @@ extern void secondary_startup(void); -static DEFINE_SPINLOCK(boot_lock); +static DEFINE_RAW_SPINLOCK(boot_lock); #ifdef CONFIG_HOTPLUG_CPU static void __ref qcom_cpu_die(unsigned int cpu) @@ -60,8 +60,8 @@ /* * Synchronise with the boot thread. */ - spin_lock(&boot_lock); - spin_unlock(&boot_lock); + raw_spin_lock(&boot_lock); + raw_spin_unlock(&boot_lock); } static int scss_release_secondary(unsigned int cpu) @@ -284,7 +284,7 @@ * set synchronisation state between this boot processor * and the secondary one */ - spin_lock(&boot_lock); + raw_spin_lock(&boot_lock); /* * Send the secondary CPU a soft interrupt, thereby causing @@ -297,7 +297,7 @@ * now the secondary core is starting up let it run its * calibrations, then wait for it to finish */ - spin_unlock(&boot_lock); + raw_spin_unlock(&boot_lock); return ret; } diff -Nur linux-3.18.14.orig/arch/arm/mach-spear/platsmp.c linux-3.18.14-rt/arch/arm/mach-spear/platsmp.c --- linux-3.18.14.orig/arch/arm/mach-spear/platsmp.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/arm/mach-spear/platsmp.c 2015-05-31 15:32:45.749635392 -0500 @@ -32,7 +32,7 @@ sync_cache_w(&pen_release); } -static DEFINE_SPINLOCK(boot_lock); +static DEFINE_RAW_SPINLOCK(boot_lock); static void __iomem *scu_base = IOMEM(VA_SCU_BASE); @@ -47,8 +47,8 @@ /* * Synchronise with the boot thread. */ - spin_lock(&boot_lock); - spin_unlock(&boot_lock); + raw_spin_lock(&boot_lock); + raw_spin_unlock(&boot_lock); } static int spear13xx_boot_secondary(unsigned int cpu, struct task_struct *idle) @@ -59,7 +59,7 @@ * set synchronisation state between this boot processor * and the secondary one */ - spin_lock(&boot_lock); + raw_spin_lock(&boot_lock); /* * The secondary processor is waiting to be released from @@ -84,7 +84,7 @@ * now the secondary core is starting up let it run its * calibrations, then wait for it to finish */ - spin_unlock(&boot_lock); + raw_spin_unlock(&boot_lock); return pen_release != -1 ? -ENOSYS : 0; } diff -Nur linux-3.18.14.orig/arch/arm/mach-sti/platsmp.c linux-3.18.14-rt/arch/arm/mach-sti/platsmp.c --- linux-3.18.14.orig/arch/arm/mach-sti/platsmp.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/arm/mach-sti/platsmp.c 2015-05-31 15:32:45.765635392 -0500 @@ -34,7 +34,7 @@ sync_cache_w(&pen_release); } -static DEFINE_SPINLOCK(boot_lock); +static DEFINE_RAW_SPINLOCK(boot_lock); static void sti_secondary_init(unsigned int cpu) { @@ -49,8 +49,8 @@ /* * Synchronise with the boot thread. */ - spin_lock(&boot_lock); - spin_unlock(&boot_lock); + raw_spin_lock(&boot_lock); + raw_spin_unlock(&boot_lock); } static int sti_boot_secondary(unsigned int cpu, struct task_struct *idle) @@ -61,7 +61,7 @@ * set synchronisation state between this boot processor * and the secondary one */ - spin_lock(&boot_lock); + raw_spin_lock(&boot_lock); /* * The secondary processor is waiting to be released from @@ -92,7 +92,7 @@ * now the secondary core is starting up let it run its * calibrations, then wait for it to finish */ - spin_unlock(&boot_lock); + raw_spin_unlock(&boot_lock); return pen_release != -1 ? -ENOSYS : 0; } diff -Nur linux-3.18.14.orig/arch/arm/mach-ux500/platsmp.c linux-3.18.14-rt/arch/arm/mach-ux500/platsmp.c --- linux-3.18.14.orig/arch/arm/mach-ux500/platsmp.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/arm/mach-ux500/platsmp.c 2015-05-31 15:32:45.793635391 -0500 @@ -51,7 +51,7 @@ return NULL; } -static DEFINE_SPINLOCK(boot_lock); +static DEFINE_RAW_SPINLOCK(boot_lock); static void ux500_secondary_init(unsigned int cpu) { @@ -64,8 +64,8 @@ /* * Synchronise with the boot thread. */ - spin_lock(&boot_lock); - spin_unlock(&boot_lock); + raw_spin_lock(&boot_lock); + raw_spin_unlock(&boot_lock); } static int ux500_boot_secondary(unsigned int cpu, struct task_struct *idle) @@ -76,7 +76,7 @@ * set synchronisation state between this boot processor * and the secondary one */ - spin_lock(&boot_lock); + raw_spin_lock(&boot_lock); /* * The secondary processor is waiting to be released from @@ -97,7 +97,7 @@ * now the secondary core is starting up let it run its * calibrations, then wait for it to finish */ - spin_unlock(&boot_lock); + raw_spin_unlock(&boot_lock); return pen_release != -1 ? -ENOSYS : 0; } diff -Nur linux-3.18.14.orig/arch/arm/mm/fault.c linux-3.18.14-rt/arch/arm/mm/fault.c --- linux-3.18.14.orig/arch/arm/mm/fault.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/arm/mm/fault.c 2015-05-31 15:32:45.797635391 -0500 @@ -277,7 +277,7 @@ * If we're in an interrupt or have no user * context, we must not take the fault.. */ - if (in_atomic() || !mm) + if (!mm || pagefault_disabled()) goto no_context; if (user_mode(regs)) @@ -431,6 +431,9 @@ if (addr < TASK_SIZE) return do_page_fault(addr, fsr, regs); + if (interrupts_enabled(regs)) + local_irq_enable(); + if (user_mode(regs)) goto bad_area; @@ -498,6 +501,9 @@ static int do_sect_fault(unsigned long addr, unsigned int fsr, struct pt_regs *regs) { + if (interrupts_enabled(regs)) + local_irq_enable(); + do_bad_area(addr, fsr, regs); return 0; } diff -Nur linux-3.18.14.orig/arch/arm/mm/highmem.c linux-3.18.14-rt/arch/arm/mm/highmem.c --- linux-3.18.14.orig/arch/arm/mm/highmem.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/arm/mm/highmem.c 2015-05-31 15:32:45.805635391 -0500 @@ -53,6 +53,7 @@ void *kmap_atomic(struct page *page) { + pte_t pte = mk_pte(page, kmap_prot); unsigned int idx; unsigned long vaddr; void *kmap; @@ -91,7 +92,10 @@ * in place, so the contained TLB flush ensures the TLB is updated * with the new mapping. */ - set_fixmap_pte(idx, mk_pte(page, kmap_prot)); +#ifdef CONFIG_PREEMPT_RT_FULL + current->kmap_pte[type] = pte; +#endif + set_fixmap_pte(idx, pte); return (void *)vaddr; } @@ -108,12 +112,15 @@ if (cache_is_vivt()) __cpuc_flush_dcache_area((void *)vaddr, PAGE_SIZE); +#ifdef CONFIG_PREEMPT_RT_FULL + current->kmap_pte[type] = __pte(0); +#endif #ifdef CONFIG_DEBUG_HIGHMEM BUG_ON(vaddr != __fix_to_virt(idx)); - set_fixmap_pte(idx, __pte(0)); #else (void) idx; /* to kill a warning */ #endif + set_fixmap_pte(idx, __pte(0)); kmap_atomic_idx_pop(); } else if (vaddr >= PKMAP_ADDR(0) && vaddr < PKMAP_ADDR(LAST_PKMAP)) { /* this address was obtained through kmap_high_get() */ @@ -125,6 +132,7 @@ void *kmap_atomic_pfn(unsigned long pfn) { + pte_t pte = pfn_pte(pfn, kmap_prot); unsigned long vaddr; int idx, type; struct page *page = pfn_to_page(pfn); @@ -139,7 +147,10 @@ #ifdef CONFIG_DEBUG_HIGHMEM BUG_ON(!pte_none(*(fixmap_page_table + idx))); #endif - set_fixmap_pte(idx, pfn_pte(pfn, kmap_prot)); +#ifdef CONFIG_PREEMPT_RT_FULL + current->kmap_pte[type] = pte; +#endif + set_fixmap_pte(idx, pte); return (void *)vaddr; } @@ -153,3 +164,28 @@ return pte_page(get_fixmap_pte(vaddr)); } + +#if defined CONFIG_PREEMPT_RT_FULL +void switch_kmaps(struct task_struct *prev_p, struct task_struct *next_p) +{ + int i; + + /* + * Clear @prev's kmap_atomic mappings + */ + for (i = 0; i < prev_p->kmap_idx; i++) { + int idx = i + KM_TYPE_NR * smp_processor_id(); + + set_fixmap_pte(idx, __pte(0)); + } + /* + * Restore @next_p's kmap_atomic mappings + */ + for (i = 0; i < next_p->kmap_idx; i++) { + int idx = i + KM_TYPE_NR * smp_processor_id(); + + if (!pte_none(next_p->kmap_pte[i])) + set_fixmap_pte(idx, next_p->kmap_pte[i]); + } +} +#endif diff -Nur linux-3.18.14.orig/arch/arm/plat-versatile/platsmp.c linux-3.18.14-rt/arch/arm/plat-versatile/platsmp.c --- linux-3.18.14.orig/arch/arm/plat-versatile/platsmp.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/arm/plat-versatile/platsmp.c 2015-05-31 15:32:45.889635390 -0500 @@ -30,7 +30,7 @@ sync_cache_w(&pen_release); } -static DEFINE_SPINLOCK(boot_lock); +static DEFINE_RAW_SPINLOCK(boot_lock); void versatile_secondary_init(unsigned int cpu) { @@ -43,8 +43,8 @@ /* * Synchronise with the boot thread. */ - spin_lock(&boot_lock); - spin_unlock(&boot_lock); + raw_spin_lock(&boot_lock); + raw_spin_unlock(&boot_lock); } int versatile_boot_secondary(unsigned int cpu, struct task_struct *idle) @@ -55,7 +55,7 @@ * Set synchronisation state between this boot processor * and the secondary one */ - spin_lock(&boot_lock); + raw_spin_lock(&boot_lock); /* * This is really belt and braces; we hold unintended secondary @@ -85,7 +85,7 @@ * now the secondary core is starting up let it run its * calibrations, then wait for it to finish */ - spin_unlock(&boot_lock); + raw_spin_unlock(&boot_lock); return pen_release != -1 ? -ENOSYS : 0; } diff -Nur linux-3.18.14.orig/arch/arm64/include/asm/thread_info.h linux-3.18.14-rt/arch/arm64/include/asm/thread_info.h --- linux-3.18.14.orig/arch/arm64/include/asm/thread_info.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/arm64/include/asm/thread_info.h 2015-05-31 15:32:45.925635390 -0500 @@ -50,6 +50,7 @@ struct exec_domain *exec_domain; /* execution domain */ struct restart_block restart_block; int preempt_count; /* 0 => preemptable, <0 => bug */ + int preempt_lazy_count; /* 0 => preemptable, <0 => bug */ int cpu; /* cpu */ }; @@ -108,6 +109,7 @@ #define TIF_NEED_RESCHED 1 #define TIF_NOTIFY_RESUME 2 /* callback before returning to user */ #define TIF_FOREIGN_FPSTATE 3 /* CPU's FP state is not current's */ +#define TIF_NEED_RESCHED_LAZY 4 #define TIF_NOHZ 7 #define TIF_SYSCALL_TRACE 8 #define TIF_SYSCALL_AUDIT 9 @@ -124,6 +126,7 @@ #define _TIF_NEED_RESCHED (1 << TIF_NEED_RESCHED) #define _TIF_NOTIFY_RESUME (1 << TIF_NOTIFY_RESUME) #define _TIF_FOREIGN_FPSTATE (1 << TIF_FOREIGN_FPSTATE) +#define _TIF_NEED_RESCHED_LAZY (1 << TIF_NEED_RESCHED_LAZY) #define _TIF_NOHZ (1 << TIF_NOHZ) #define _TIF_SYSCALL_TRACE (1 << TIF_SYSCALL_TRACE) #define _TIF_SYSCALL_AUDIT (1 << TIF_SYSCALL_AUDIT) diff -Nur linux-3.18.14.orig/arch/arm64/Kconfig linux-3.18.14-rt/arch/arm64/Kconfig --- linux-3.18.14.orig/arch/arm64/Kconfig 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/arm64/Kconfig 2015-05-31 15:32:45.905635390 -0500 @@ -59,8 +59,10 @@ select HAVE_PERF_REGS select HAVE_PERF_USER_STACK_DUMP select HAVE_RCU_TABLE_FREE + select HAVE_PREEMPT_LAZY select HAVE_SYSCALL_TRACEPOINTS select IRQ_DOMAIN + select IRQ_FORCED_THREADING select MODULES_USE_ELF_RELA select NO_BOOTMEM select OF diff -Nur linux-3.18.14.orig/arch/arm64/kernel/asm-offsets.c linux-3.18.14-rt/arch/arm64/kernel/asm-offsets.c --- linux-3.18.14.orig/arch/arm64/kernel/asm-offsets.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/arm64/kernel/asm-offsets.c 2015-05-31 15:32:45.925635390 -0500 @@ -36,6 +36,7 @@ BLANK(); DEFINE(TI_FLAGS, offsetof(struct thread_info, flags)); DEFINE(TI_PREEMPT, offsetof(struct thread_info, preempt_count)); + DEFINE(TI_PREEMPT_LAZY, offsetof(struct thread_info, preempt_lazy_count)); DEFINE(TI_ADDR_LIMIT, offsetof(struct thread_info, addr_limit)); DEFINE(TI_TASK, offsetof(struct thread_info, task)); DEFINE(TI_EXEC_DOMAIN, offsetof(struct thread_info, exec_domain)); diff -Nur linux-3.18.14.orig/arch/arm64/kernel/entry.S linux-3.18.14-rt/arch/arm64/kernel/entry.S --- linux-3.18.14.orig/arch/arm64/kernel/entry.S 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/arm64/kernel/entry.S 2015-05-31 15:32:45.925635390 -0500 @@ -367,11 +367,16 @@ #ifdef CONFIG_PREEMPT get_thread_info tsk ldr w24, [tsk, #TI_PREEMPT] // get preempt count - cbnz w24, 1f // preempt count != 0 + cbnz w24, 2f // preempt count != 0 ldr x0, [tsk, #TI_FLAGS] // get flags - tbz x0, #TIF_NEED_RESCHED, 1f // needs rescheduling? - bl el1_preempt + tbnz x0, #TIF_NEED_RESCHED, 1f // needs rescheduling? + + ldr w24, [tsk, #TI_PREEMPT_LAZY] // get preempt lazy count + cbnz w24, 2f // preempt lazy count != 0 + tbz x0, #TIF_NEED_RESCHED_LAZY, 2f // needs rescheduling? 1: + bl el1_preempt +2: #endif #ifdef CONFIG_TRACE_IRQFLAGS bl trace_hardirqs_on @@ -385,6 +390,7 @@ 1: bl preempt_schedule_irq // irq en/disable is done inside ldr x0, [tsk, #TI_FLAGS] // get new tasks TI_FLAGS tbnz x0, #TIF_NEED_RESCHED, 1b // needs rescheduling? + tbnz x0, #TIF_NEED_RESCHED_LAZY, 1b // needs rescheduling? ret x24 #endif @@ -621,6 +627,7 @@ str x0, [sp, #S_X0] // returned x0 work_pending: tbnz x1, #TIF_NEED_RESCHED, work_resched + tbnz x1, #TIF_NEED_RESCHED_LAZY, work_resched /* TIF_SIGPENDING, TIF_NOTIFY_RESUME or TIF_FOREIGN_FPSTATE case */ ldr x2, [sp, #S_PSTATE] mov x0, sp // 'regs' diff -Nur linux-3.18.14.orig/arch/arm64/kernel/perf_event.c linux-3.18.14-rt/arch/arm64/kernel/perf_event.c --- linux-3.18.14.orig/arch/arm64/kernel/perf_event.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/arm64/kernel/perf_event.c 2015-05-31 15:32:45.925635390 -0500 @@ -461,7 +461,7 @@ } err = request_irq(irq, armpmu->handle_irq, - IRQF_NOBALANCING, + IRQF_NOBALANCING | IRQF_NO_THREAD, "arm-pmu", armpmu); if (err) { pr_err("unable to request IRQ%d for ARM PMU counters\n", diff -Nur linux-3.18.14.orig/arch/avr32/mm/fault.c linux-3.18.14-rt/arch/avr32/mm/fault.c --- linux-3.18.14.orig/arch/avr32/mm/fault.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/avr32/mm/fault.c 2015-05-31 15:32:45.933635390 -0500 @@ -81,7 +81,7 @@ * If we're in an interrupt or have no user context, we must * not take the fault... */ - if (in_atomic() || !mm || regs->sr & SYSREG_BIT(GM)) + if (!mm || regs->sr & SYSREG_BIT(GM) || pagefault_disabled()) goto no_context; local_irq_enable(); diff -Nur linux-3.18.14.orig/arch/cris/mm/fault.c linux-3.18.14-rt/arch/cris/mm/fault.c --- linux-3.18.14.orig/arch/cris/mm/fault.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/cris/mm/fault.c 2015-05-31 15:32:45.945635390 -0500 @@ -113,7 +113,7 @@ * user context, we must not take the fault. */ - if (in_atomic() || !mm) + if (!mm || pagefault_disabled()) goto no_context; if (user_mode(regs)) diff -Nur linux-3.18.14.orig/arch/frv/mm/fault.c linux-3.18.14-rt/arch/frv/mm/fault.c --- linux-3.18.14.orig/arch/frv/mm/fault.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/frv/mm/fault.c 2015-05-31 15:32:45.953635390 -0500 @@ -78,7 +78,7 @@ * If we're in an interrupt or have no user * context, we must not take the fault.. */ - if (in_atomic() || !mm) + if (!mm || pagefault_disabled()) goto no_context; if (user_mode(__frame)) diff -Nur linux-3.18.14.orig/arch/ia64/mm/fault.c linux-3.18.14-rt/arch/ia64/mm/fault.c --- linux-3.18.14.orig/arch/ia64/mm/fault.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/ia64/mm/fault.c 2015-05-31 15:32:45.961635389 -0500 @@ -96,7 +96,7 @@ /* * If we're in an interrupt or have no user context, we must not take the fault.. */ - if (in_atomic() || !mm) + if (!mm || pagefault_disabled()) goto no_context; #ifdef CONFIG_VIRTUAL_MEM_MAP diff -Nur linux-3.18.14.orig/arch/Kconfig linux-3.18.14-rt/arch/Kconfig --- linux-3.18.14.orig/arch/Kconfig 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/Kconfig 2015-05-31 15:32:45.501635394 -0500 @@ -6,6 +6,7 @@ tristate "OProfile system profiling" depends on PROFILING depends on HAVE_OPROFILE + depends on !PREEMPT_RT_FULL select RING_BUFFER select RING_BUFFER_ALLOW_SWAP help diff -Nur linux-3.18.14.orig/arch/m32r/mm/fault.c linux-3.18.14-rt/arch/m32r/mm/fault.c --- linux-3.18.14.orig/arch/m32r/mm/fault.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/m32r/mm/fault.c 2015-05-31 15:32:45.985635389 -0500 @@ -114,7 +114,7 @@ * If we're in an interrupt or have no user context or are running in an * atomic region then we must not take the fault.. */ - if (in_atomic() || !mm) + if (!mm || pagefault_disabled()) goto bad_area_nosemaphore; if (error_code & ACE_USERMODE) diff -Nur linux-3.18.14.orig/arch/m68k/mm/fault.c linux-3.18.14-rt/arch/m68k/mm/fault.c --- linux-3.18.14.orig/arch/m68k/mm/fault.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/m68k/mm/fault.c 2015-05-31 15:32:45.985635389 -0500 @@ -81,7 +81,7 @@ * If we're in an interrupt or have no user * context, we must not take the fault.. */ - if (in_atomic() || !mm) + if (!mm || pagefault_disabled()) goto no_context; if (user_mode(regs)) diff -Nur linux-3.18.14.orig/arch/microblaze/mm/fault.c linux-3.18.14-rt/arch/microblaze/mm/fault.c --- linux-3.18.14.orig/arch/microblaze/mm/fault.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/microblaze/mm/fault.c 2015-05-31 15:32:46.005635389 -0500 @@ -107,7 +107,7 @@ if ((error_code & 0x13) == 0x13 || (error_code & 0x11) == 0x11) is_write = 0; - if (unlikely(in_atomic() || !mm)) { + if (unlikely(!mm || pagefault_disabled())) { if (kernel_mode(regs)) goto bad_area_nosemaphore; diff -Nur linux-3.18.14.orig/arch/mips/Kconfig linux-3.18.14-rt/arch/mips/Kconfig --- linux-3.18.14.orig/arch/mips/Kconfig 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/mips/Kconfig 2015-05-31 15:32:46.033635389 -0500 @@ -2196,7 +2196,7 @@ # config HIGHMEM bool "High Memory Support" - depends on 32BIT && CPU_SUPPORTS_HIGHMEM && SYS_SUPPORTS_HIGHMEM && !CPU_MIPS32_3_5_EVA + depends on 32BIT && CPU_SUPPORTS_HIGHMEM && SYS_SUPPORTS_HIGHMEM && !CPU_MIPS32_3_5_EVA && !PREEMPT_RT_FULL config CPU_SUPPORTS_HIGHMEM bool diff -Nur linux-3.18.14.orig/arch/mips/kernel/signal.c linux-3.18.14-rt/arch/mips/kernel/signal.c --- linux-3.18.14.orig/arch/mips/kernel/signal.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/mips/kernel/signal.c 2015-05-31 15:32:46.057635389 -0500 @@ -613,6 +613,7 @@ __u32 thread_info_flags) { local_irq_enable(); + preempt_check_resched(); user_exit(); diff -Nur linux-3.18.14.orig/arch/mips/mm/fault.c linux-3.18.14-rt/arch/mips/mm/fault.c --- linux-3.18.14.orig/arch/mips/mm/fault.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/mips/mm/fault.c 2015-05-31 15:32:46.069635388 -0500 @@ -89,7 +89,7 @@ * If we're in an interrupt or have no user * context, we must not take the fault.. */ - if (in_atomic() || !mm) + if (!mm || pagefault_disabled()) goto bad_area_nosemaphore; if (user_mode(regs)) diff -Nur linux-3.18.14.orig/arch/mips/mm/init.c linux-3.18.14-rt/arch/mips/mm/init.c --- linux-3.18.14.orig/arch/mips/mm/init.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/mips/mm/init.c 2015-05-31 15:32:46.069635388 -0500 @@ -90,7 +90,7 @@ BUG_ON(Page_dcache_dirty(page)); - pagefault_disable(); + raw_pagefault_disable(); idx = (addr >> PAGE_SHIFT) & (FIX_N_COLOURS - 1); idx += in_interrupt() ? FIX_N_COLOURS : 0; vaddr = __fix_to_virt(FIX_CMAP_END - idx); @@ -146,7 +146,7 @@ tlbw_use_hazard(); write_c0_entryhi(old_ctx); local_irq_restore(flags); - pagefault_enable(); + raw_pagefault_enable(); } void copy_user_highpage(struct page *to, struct page *from, diff -Nur linux-3.18.14.orig/arch/mn10300/mm/fault.c linux-3.18.14-rt/arch/mn10300/mm/fault.c --- linux-3.18.14.orig/arch/mn10300/mm/fault.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/mn10300/mm/fault.c 2015-05-31 15:32:46.113635388 -0500 @@ -168,7 +168,7 @@ * If we're in an interrupt or have no user * context, we must not take the fault.. */ - if (in_atomic() || !mm) + if (!mm || pagefault_disabled()) goto no_context; if ((fault_code & MMUFCR_xFC_ACCESS) == MMUFCR_xFC_ACCESS_USR) diff -Nur linux-3.18.14.orig/arch/parisc/mm/fault.c linux-3.18.14-rt/arch/parisc/mm/fault.c --- linux-3.18.14.orig/arch/parisc/mm/fault.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/parisc/mm/fault.c 2015-05-31 15:32:46.113635388 -0500 @@ -207,7 +207,7 @@ int fault; unsigned int flags; - if (in_atomic()) + if (pagefault_disabled()) goto no_context; tsk = current; diff -Nur linux-3.18.14.orig/arch/powerpc/include/asm/kvm_host.h linux-3.18.14-rt/arch/powerpc/include/asm/kvm_host.h --- linux-3.18.14.orig/arch/powerpc/include/asm/kvm_host.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/powerpc/include/asm/kvm_host.h 2015-05-31 15:32:46.145635388 -0500 @@ -296,7 +296,7 @@ u8 in_guest; struct list_head runnable_threads; spinlock_t lock; - wait_queue_head_t wq; + struct swait_head wq; u64 stolen_tb; u64 preempt_tb; struct kvm_vcpu *runner; @@ -618,7 +618,7 @@ u8 prodded; u32 last_inst; - wait_queue_head_t *wqp; + struct swait_head *wqp; struct kvmppc_vcore *vcore; int ret; int trap; diff -Nur linux-3.18.14.orig/arch/powerpc/include/asm/thread_info.h linux-3.18.14-rt/arch/powerpc/include/asm/thread_info.h --- linux-3.18.14.orig/arch/powerpc/include/asm/thread_info.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/powerpc/include/asm/thread_info.h 2015-05-31 15:32:46.165635388 -0500 @@ -43,6 +43,8 @@ int cpu; /* cpu we're on */ int preempt_count; /* 0 => preemptable, <0 => BUG */ + int preempt_lazy_count; /* 0 => preemptable, + <0 => BUG */ struct restart_block restart_block; unsigned long local_flags; /* private flags for thread */ @@ -88,8 +90,7 @@ #define TIF_SYSCALL_TRACE 0 /* syscall trace active */ #define TIF_SIGPENDING 1 /* signal pending */ #define TIF_NEED_RESCHED 2 /* rescheduling necessary */ -#define TIF_POLLING_NRFLAG 3 /* true if poll_idle() is polling - TIF_NEED_RESCHED */ +#define TIF_NEED_RESCHED_LAZY 3 /* lazy rescheduling necessary */ #define TIF_32BIT 4 /* 32 bit binary */ #define TIF_RESTORE_TM 5 /* need to restore TM FP/VEC/VSX */ #define TIF_SYSCALL_AUDIT 7 /* syscall auditing active */ @@ -107,6 +108,8 @@ #if defined(CONFIG_PPC64) #define TIF_ELF2ABI 18 /* function descriptors must die! */ #endif +#define TIF_POLLING_NRFLAG 19 /* true if poll_idle() is polling + TIF_NEED_RESCHED */ /* as above, but as bit values */ #define _TIF_SYSCALL_TRACE (1<flags) set_bits(irqtp->flags, &curtp->flags); } +#endif irq_hw_number_t virq_to_hw(unsigned int virq) { diff -Nur linux-3.18.14.orig/arch/powerpc/kernel/misc_32.S linux-3.18.14-rt/arch/powerpc/kernel/misc_32.S --- linux-3.18.14.orig/arch/powerpc/kernel/misc_32.S 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/powerpc/kernel/misc_32.S 2015-05-31 15:32:46.261635387 -0500 @@ -40,6 +40,7 @@ * We store the saved ksp_limit in the unused part * of the STACK_FRAME_OVERHEAD */ +#ifndef CONFIG_PREEMPT_RT_FULL _GLOBAL(call_do_softirq) mflr r0 stw r0,4(r1) @@ -56,6 +57,7 @@ stw r10,THREAD+KSP_LIMIT(r2) mtlr r0 blr +#endif /* * void call_do_irq(struct pt_regs *regs, struct thread_info *irqtp); diff -Nur linux-3.18.14.orig/arch/powerpc/kernel/misc_64.S linux-3.18.14-rt/arch/powerpc/kernel/misc_64.S --- linux-3.18.14.orig/arch/powerpc/kernel/misc_64.S 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/powerpc/kernel/misc_64.S 2015-05-31 15:32:46.261635387 -0500 @@ -29,6 +29,7 @@ .text +#ifndef CONFIG_PREEMPT_RT_FULL _GLOBAL(call_do_softirq) mflr r0 std r0,16(r1) @@ -39,6 +40,7 @@ ld r0,16(r1) mtlr r0 blr +#endif _GLOBAL(call_do_irq) mflr r0 diff -Nur linux-3.18.14.orig/arch/powerpc/kernel/time.c linux-3.18.14-rt/arch/powerpc/kernel/time.c --- linux-3.18.14.orig/arch/powerpc/kernel/time.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/powerpc/kernel/time.c 2015-05-31 15:32:46.261635387 -0500 @@ -424,7 +424,7 @@ EXPORT_SYMBOL(profile_pc); #endif -#ifdef CONFIG_IRQ_WORK +#if defined(CONFIG_IRQ_WORK) /* * 64-bit uses a byte in the PACA, 32-bit uses a per-cpu variable... diff -Nur linux-3.18.14.orig/arch/powerpc/kvm/book3s_hv.c linux-3.18.14-rt/arch/powerpc/kvm/book3s_hv.c --- linux-3.18.14.orig/arch/powerpc/kvm/book3s_hv.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/powerpc/kvm/book3s_hv.c 2015-05-31 15:32:46.301635387 -0500 @@ -84,11 +84,11 @@ { int me; int cpu = vcpu->cpu; - wait_queue_head_t *wqp; + struct swait_head *wqp; wqp = kvm_arch_vcpu_wq(vcpu); - if (waitqueue_active(wqp)) { - wake_up_interruptible(wqp); + if (swaitqueue_active(wqp)) { + swait_wake_interruptible(wqp); ++vcpu->stat.halt_wakeup; } @@ -639,8 +639,8 @@ tvcpu->arch.prodded = 1; smp_mb(); if (vcpu->arch.ceded) { - if (waitqueue_active(&vcpu->wq)) { - wake_up_interruptible(&vcpu->wq); + if (swaitqueue_active(&vcpu->wq)) { + swait_wake_interruptible(&vcpu->wq); vcpu->stat.halt_wakeup++; } } @@ -1357,7 +1357,7 @@ INIT_LIST_HEAD(&vcore->runnable_threads); spin_lock_init(&vcore->lock); - init_waitqueue_head(&vcore->wq); + init_swait_head(&vcore->wq); vcore->preempt_tb = TB_NIL; vcore->lpcr = kvm->arch.lpcr; vcore->first_vcpuid = core * threads_per_subcore; @@ -1826,13 +1826,13 @@ */ static void kvmppc_vcore_blocked(struct kvmppc_vcore *vc) { - DEFINE_WAIT(wait); + DEFINE_SWAITER(wait); - prepare_to_wait(&vc->wq, &wait, TASK_INTERRUPTIBLE); + swait_prepare(&vc->wq, &wait, TASK_INTERRUPTIBLE); vc->vcore_state = VCORE_SLEEPING; spin_unlock(&vc->lock); schedule(); - finish_wait(&vc->wq, &wait); + swait_finish(&vc->wq, &wait); spin_lock(&vc->lock); vc->vcore_state = VCORE_INACTIVE; } @@ -1873,7 +1873,7 @@ kvmppc_create_dtl_entry(vcpu, vc); kvmppc_start_thread(vcpu); } else if (vc->vcore_state == VCORE_SLEEPING) { - wake_up(&vc->wq); + swait_wake(&vc->wq); } } diff -Nur linux-3.18.14.orig/arch/powerpc/kvm/Kconfig linux-3.18.14-rt/arch/powerpc/kvm/Kconfig --- linux-3.18.14.orig/arch/powerpc/kvm/Kconfig 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/powerpc/kvm/Kconfig 2015-05-31 15:32:46.281635387 -0500 @@ -157,6 +157,7 @@ config KVM_MPIC bool "KVM in-kernel MPIC emulation" depends on KVM && E500 + depends on !PREEMPT_RT_FULL select HAVE_KVM_IRQCHIP select HAVE_KVM_IRQFD select HAVE_KVM_IRQ_ROUTING diff -Nur linux-3.18.14.orig/arch/powerpc/mm/fault.c linux-3.18.14-rt/arch/powerpc/mm/fault.c --- linux-3.18.14.orig/arch/powerpc/mm/fault.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/powerpc/mm/fault.c 2015-05-31 15:32:46.325635386 -0500 @@ -273,7 +273,7 @@ if (!arch_irq_disabled_regs(regs)) local_irq_enable(); - if (in_atomic() || mm == NULL) { + if (in_atomic() || mm == NULL || pagefault_disabled()) { if (!user_mode(regs)) { rc = SIGSEGV; goto bail; diff -Nur linux-3.18.14.orig/arch/s390/include/asm/kvm_host.h linux-3.18.14-rt/arch/s390/include/asm/kvm_host.h --- linux-3.18.14.orig/arch/s390/include/asm/kvm_host.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/s390/include/asm/kvm_host.h 2015-05-31 15:32:46.369635386 -0500 @@ -311,7 +311,7 @@ struct list_head list; atomic_t active; struct kvm_s390_float_interrupt *float_int; - wait_queue_head_t *wq; + struct swait_head *wq; atomic_t *cpuflags; unsigned int action_bits; }; diff -Nur linux-3.18.14.orig/arch/s390/kvm/interrupt.c linux-3.18.14-rt/arch/s390/kvm/interrupt.c --- linux-3.18.14.orig/arch/s390/kvm/interrupt.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/s390/kvm/interrupt.c 2015-05-31 15:32:46.385635386 -0500 @@ -620,13 +620,13 @@ void kvm_s390_vcpu_wakeup(struct kvm_vcpu *vcpu) { - if (waitqueue_active(&vcpu->wq)) { + if (swaitqueue_active(&vcpu->wq)) { /* * The vcpu gave up the cpu voluntarily, mark it as a good * yield-candidate. */ vcpu->preempted = true; - wake_up_interruptible(&vcpu->wq); + swait_wake_interruptible(&vcpu->wq); vcpu->stat.halt_wakeup++; } } @@ -747,7 +747,7 @@ spin_lock(&li->lock); list_add(&inti->list, &li->list); atomic_set(&li->active, 1); - BUG_ON(waitqueue_active(li->wq)); + BUG_ON(swaitqueue_active(li->wq)); spin_unlock(&li->lock); return 0; } @@ -772,7 +772,7 @@ spin_lock(&li->lock); list_add(&inti->list, &li->list); atomic_set(&li->active, 1); - BUG_ON(waitqueue_active(li->wq)); + BUG_ON(swaitqueue_active(li->wq)); spin_unlock(&li->lock); return 0; } diff -Nur linux-3.18.14.orig/arch/s390/kvm/interrupt.c.orig linux-3.18.14-rt/arch/s390/kvm/interrupt.c.orig --- linux-3.18.14.orig/arch/s390/kvm/interrupt.c.orig 1969-12-31 18:00:00.000000000 -0600 +++ linux-3.18.14-rt/arch/s390/kvm/interrupt.c.orig 2015-05-20 10:04:50.000000000 -0500 @@ -0,0 +1,1541 @@ +/* + * handling kvm guest interrupts + * + * Copyright IBM Corp. 2008,2014 + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License (version 2 only) + * as published by the Free Software Foundation. + * + * Author(s): Carsten Otte + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include "kvm-s390.h" +#include "gaccess.h" +#include "trace-s390.h" + +#define IOINT_SCHID_MASK 0x0000ffff +#define IOINT_SSID_MASK 0x00030000 +#define IOINT_CSSID_MASK 0x03fc0000 +#define IOINT_AI_MASK 0x04000000 +#define PFAULT_INIT 0x0600 + +static int __must_check deliver_ckc_interrupt(struct kvm_vcpu *vcpu); + +static int is_ioint(u64 type) +{ + return ((type & 0xfffe0000u) != 0xfffe0000u); +} + +int psw_extint_disabled(struct kvm_vcpu *vcpu) +{ + return !(vcpu->arch.sie_block->gpsw.mask & PSW_MASK_EXT); +} + +static int psw_ioint_disabled(struct kvm_vcpu *vcpu) +{ + return !(vcpu->arch.sie_block->gpsw.mask & PSW_MASK_IO); +} + +static int psw_mchk_disabled(struct kvm_vcpu *vcpu) +{ + return !(vcpu->arch.sie_block->gpsw.mask & PSW_MASK_MCHECK); +} + +static int psw_interrupts_disabled(struct kvm_vcpu *vcpu) +{ + if ((vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PER) || + (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_IO) || + (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_EXT)) + return 0; + return 1; +} + +static int ckc_interrupts_enabled(struct kvm_vcpu *vcpu) +{ + if (psw_extint_disabled(vcpu) || + !(vcpu->arch.sie_block->gcr[0] & 0x800ul)) + return 0; + if (guestdbg_enabled(vcpu) && guestdbg_sstep_enabled(vcpu)) + /* No timer interrupts when single stepping */ + return 0; + return 1; +} + +static u64 int_word_to_isc_bits(u32 int_word) +{ + u8 isc = (int_word & 0x38000000) >> 27; + + return (0x80 >> isc) << 24; +} + +static int __must_check __interrupt_is_deliverable(struct kvm_vcpu *vcpu, + struct kvm_s390_interrupt_info *inti) +{ + switch (inti->type) { + case KVM_S390_INT_EXTERNAL_CALL: + if (psw_extint_disabled(vcpu)) + return 0; + if (vcpu->arch.sie_block->gcr[0] & 0x2000ul) + return 1; + return 0; + case KVM_S390_INT_EMERGENCY: + if (psw_extint_disabled(vcpu)) + return 0; + if (vcpu->arch.sie_block->gcr[0] & 0x4000ul) + return 1; + return 0; + case KVM_S390_INT_CLOCK_COMP: + return ckc_interrupts_enabled(vcpu); + case KVM_S390_INT_CPU_TIMER: + if (psw_extint_disabled(vcpu)) + return 0; + if (vcpu->arch.sie_block->gcr[0] & 0x400ul) + return 1; + return 0; + case KVM_S390_INT_SERVICE: + case KVM_S390_INT_PFAULT_INIT: + case KVM_S390_INT_PFAULT_DONE: + case KVM_S390_INT_VIRTIO: + if (psw_extint_disabled(vcpu)) + return 0; + if (vcpu->arch.sie_block->gcr[0] & 0x200ul) + return 1; + return 0; + case KVM_S390_PROGRAM_INT: + case KVM_S390_SIGP_STOP: + case KVM_S390_SIGP_SET_PREFIX: + case KVM_S390_RESTART: + return 1; + case KVM_S390_MCHK: + if (psw_mchk_disabled(vcpu)) + return 0; + if (vcpu->arch.sie_block->gcr[14] & inti->mchk.cr14) + return 1; + return 0; + case KVM_S390_INT_IO_MIN...KVM_S390_INT_IO_MAX: + if (psw_ioint_disabled(vcpu)) + return 0; + if (vcpu->arch.sie_block->gcr[6] & + int_word_to_isc_bits(inti->io.io_int_word)) + return 1; + return 0; + default: + printk(KERN_WARNING "illegal interrupt type %llx\n", + inti->type); + BUG(); + } + return 0; +} + +static void __set_cpu_idle(struct kvm_vcpu *vcpu) +{ + atomic_set_mask(CPUSTAT_WAIT, &vcpu->arch.sie_block->cpuflags); + set_bit(vcpu->vcpu_id, vcpu->arch.local_int.float_int->idle_mask); +} + +static void __unset_cpu_idle(struct kvm_vcpu *vcpu) +{ + atomic_clear_mask(CPUSTAT_WAIT, &vcpu->arch.sie_block->cpuflags); + clear_bit(vcpu->vcpu_id, vcpu->arch.local_int.float_int->idle_mask); +} + +static void __reset_intercept_indicators(struct kvm_vcpu *vcpu) +{ + atomic_clear_mask(CPUSTAT_IO_INT | CPUSTAT_EXT_INT | CPUSTAT_STOP_INT, + &vcpu->arch.sie_block->cpuflags); + vcpu->arch.sie_block->lctl = 0x0000; + vcpu->arch.sie_block->ictl &= ~(ICTL_LPSW | ICTL_STCTL | ICTL_PINT); + + if (guestdbg_enabled(vcpu)) { + vcpu->arch.sie_block->lctl |= (LCTL_CR0 | LCTL_CR9 | + LCTL_CR10 | LCTL_CR11); + vcpu->arch.sie_block->ictl |= (ICTL_STCTL | ICTL_PINT); + } + + if (vcpu->arch.local_int.action_bits & ACTION_STOP_ON_STOP) + atomic_set_mask(CPUSTAT_STOP_INT, &vcpu->arch.sie_block->cpuflags); +} + +static void __set_cpuflag(struct kvm_vcpu *vcpu, u32 flag) +{ + atomic_set_mask(flag, &vcpu->arch.sie_block->cpuflags); +} + +static void __set_intercept_indicator(struct kvm_vcpu *vcpu, + struct kvm_s390_interrupt_info *inti) +{ + switch (inti->type) { + case KVM_S390_INT_EXTERNAL_CALL: + case KVM_S390_INT_EMERGENCY: + case KVM_S390_INT_SERVICE: + case KVM_S390_INT_PFAULT_INIT: + case KVM_S390_INT_PFAULT_DONE: + case KVM_S390_INT_VIRTIO: + case KVM_S390_INT_CLOCK_COMP: + case KVM_S390_INT_CPU_TIMER: + if (psw_extint_disabled(vcpu)) + __set_cpuflag(vcpu, CPUSTAT_EXT_INT); + else + vcpu->arch.sie_block->lctl |= LCTL_CR0; + break; + case KVM_S390_SIGP_STOP: + __set_cpuflag(vcpu, CPUSTAT_STOP_INT); + break; + case KVM_S390_MCHK: + if (psw_mchk_disabled(vcpu)) + vcpu->arch.sie_block->ictl |= ICTL_LPSW; + else + vcpu->arch.sie_block->lctl |= LCTL_CR14; + break; + case KVM_S390_INT_IO_MIN...KVM_S390_INT_IO_MAX: + if (psw_ioint_disabled(vcpu)) + __set_cpuflag(vcpu, CPUSTAT_IO_INT); + else + vcpu->arch.sie_block->lctl |= LCTL_CR6; + break; + default: + BUG(); + } +} + +static u16 get_ilc(struct kvm_vcpu *vcpu) +{ + const unsigned short table[] = { 2, 4, 4, 6 }; + + switch (vcpu->arch.sie_block->icptcode) { + case ICPT_INST: + case ICPT_INSTPROGI: + case ICPT_OPEREXC: + case ICPT_PARTEXEC: + case ICPT_IOINST: + /* last instruction only stored for these icptcodes */ + return table[vcpu->arch.sie_block->ipa >> 14]; + case ICPT_PROGI: + return vcpu->arch.sie_block->pgmilc; + default: + return 0; + } +} + +static int __must_check __deliver_prog_irq(struct kvm_vcpu *vcpu, + struct kvm_s390_pgm_info *pgm_info) +{ + int rc = 0; + u16 ilc = get_ilc(vcpu); + + switch (pgm_info->code & ~PGM_PER) { + case PGM_AFX_TRANSLATION: + case PGM_ASX_TRANSLATION: + case PGM_EX_TRANSLATION: + case PGM_LFX_TRANSLATION: + case PGM_LSTE_SEQUENCE: + case PGM_LSX_TRANSLATION: + case PGM_LX_TRANSLATION: + case PGM_PRIMARY_AUTHORITY: + case PGM_SECONDARY_AUTHORITY: + case PGM_SPACE_SWITCH: + rc = put_guest_lc(vcpu, pgm_info->trans_exc_code, + (u64 *)__LC_TRANS_EXC_CODE); + break; + case PGM_ALEN_TRANSLATION: + case PGM_ALE_SEQUENCE: + case PGM_ASTE_INSTANCE: + case PGM_ASTE_SEQUENCE: + case PGM_ASTE_VALIDITY: + case PGM_EXTENDED_AUTHORITY: + rc = put_guest_lc(vcpu, pgm_info->exc_access_id, + (u8 *)__LC_EXC_ACCESS_ID); + break; + case PGM_ASCE_TYPE: + case PGM_PAGE_TRANSLATION: + case PGM_REGION_FIRST_TRANS: + case PGM_REGION_SECOND_TRANS: + case PGM_REGION_THIRD_TRANS: + case PGM_SEGMENT_TRANSLATION: + rc = put_guest_lc(vcpu, pgm_info->trans_exc_code, + (u64 *)__LC_TRANS_EXC_CODE); + rc |= put_guest_lc(vcpu, pgm_info->exc_access_id, + (u8 *)__LC_EXC_ACCESS_ID); + rc |= put_guest_lc(vcpu, pgm_info->op_access_id, + (u8 *)__LC_OP_ACCESS_ID); + break; + case PGM_MONITOR: + rc = put_guest_lc(vcpu, pgm_info->mon_class_nr, + (u16 *)__LC_MON_CLASS_NR); + rc |= put_guest_lc(vcpu, pgm_info->mon_code, + (u64 *)__LC_MON_CODE); + break; + case PGM_DATA: + rc = put_guest_lc(vcpu, pgm_info->data_exc_code, + (u32 *)__LC_DATA_EXC_CODE); + break; + case PGM_PROTECTION: + rc = put_guest_lc(vcpu, pgm_info->trans_exc_code, + (u64 *)__LC_TRANS_EXC_CODE); + rc |= put_guest_lc(vcpu, pgm_info->exc_access_id, + (u8 *)__LC_EXC_ACCESS_ID); + break; + } + + if (pgm_info->code & PGM_PER) { + rc |= put_guest_lc(vcpu, pgm_info->per_code, + (u8 *) __LC_PER_CODE); + rc |= put_guest_lc(vcpu, pgm_info->per_atmid, + (u8 *)__LC_PER_ATMID); + rc |= put_guest_lc(vcpu, pgm_info->per_address, + (u64 *) __LC_PER_ADDRESS); + rc |= put_guest_lc(vcpu, pgm_info->per_access_id, + (u8 *) __LC_PER_ACCESS_ID); + } + + rc |= put_guest_lc(vcpu, ilc, (u16 *) __LC_PGM_ILC); + rc |= put_guest_lc(vcpu, pgm_info->code, + (u16 *)__LC_PGM_INT_CODE); + rc |= write_guest_lc(vcpu, __LC_PGM_OLD_PSW, + &vcpu->arch.sie_block->gpsw, sizeof(psw_t)); + rc |= read_guest_lc(vcpu, __LC_PGM_NEW_PSW, + &vcpu->arch.sie_block->gpsw, sizeof(psw_t)); + + return rc; +} + +static int __must_check __do_deliver_interrupt(struct kvm_vcpu *vcpu, + struct kvm_s390_interrupt_info *inti) +{ + const unsigned short table[] = { 2, 4, 4, 6 }; + int rc = 0; + + switch (inti->type) { + case KVM_S390_INT_EMERGENCY: + VCPU_EVENT(vcpu, 4, "%s", "interrupt: sigp emerg"); + vcpu->stat.deliver_emergency_signal++; + trace_kvm_s390_deliver_interrupt(vcpu->vcpu_id, inti->type, + inti->emerg.code, 0); + rc = put_guest_lc(vcpu, 0x1201, (u16 *)__LC_EXT_INT_CODE); + rc |= put_guest_lc(vcpu, inti->emerg.code, + (u16 *)__LC_EXT_CPU_ADDR); + rc |= write_guest_lc(vcpu, __LC_EXT_OLD_PSW, + &vcpu->arch.sie_block->gpsw, sizeof(psw_t)); + rc |= read_guest_lc(vcpu, __LC_EXT_NEW_PSW, + &vcpu->arch.sie_block->gpsw, sizeof(psw_t)); + break; + case KVM_S390_INT_EXTERNAL_CALL: + VCPU_EVENT(vcpu, 4, "%s", "interrupt: sigp ext call"); + vcpu->stat.deliver_external_call++; + trace_kvm_s390_deliver_interrupt(vcpu->vcpu_id, inti->type, + inti->extcall.code, 0); + rc = put_guest_lc(vcpu, 0x1202, (u16 *)__LC_EXT_INT_CODE); + rc |= put_guest_lc(vcpu, inti->extcall.code, + (u16 *)__LC_EXT_CPU_ADDR); + rc |= write_guest_lc(vcpu, __LC_EXT_OLD_PSW, + &vcpu->arch.sie_block->gpsw, + sizeof(psw_t)); + rc |= read_guest_lc(vcpu, __LC_EXT_NEW_PSW, + &vcpu->arch.sie_block->gpsw, + sizeof(psw_t)); + break; + case KVM_S390_INT_CLOCK_COMP: + trace_kvm_s390_deliver_interrupt(vcpu->vcpu_id, inti->type, + inti->ext.ext_params, 0); + rc = deliver_ckc_interrupt(vcpu); + break; + case KVM_S390_INT_CPU_TIMER: + trace_kvm_s390_deliver_interrupt(vcpu->vcpu_id, inti->type, + inti->ext.ext_params, 0); + rc = put_guest_lc(vcpu, EXT_IRQ_CPU_TIMER, + (u16 *)__LC_EXT_INT_CODE); + rc |= write_guest_lc(vcpu, __LC_EXT_OLD_PSW, + &vcpu->arch.sie_block->gpsw, + sizeof(psw_t)); + rc |= read_guest_lc(vcpu, __LC_EXT_NEW_PSW, + &vcpu->arch.sie_block->gpsw, sizeof(psw_t)); + rc |= put_guest_lc(vcpu, inti->ext.ext_params, + (u32 *)__LC_EXT_PARAMS); + break; + case KVM_S390_INT_SERVICE: + VCPU_EVENT(vcpu, 4, "interrupt: sclp parm:%x", + inti->ext.ext_params); + vcpu->stat.deliver_service_signal++; + trace_kvm_s390_deliver_interrupt(vcpu->vcpu_id, inti->type, + inti->ext.ext_params, 0); + rc = put_guest_lc(vcpu, 0x2401, (u16 *)__LC_EXT_INT_CODE); + rc |= write_guest_lc(vcpu, __LC_EXT_OLD_PSW, + &vcpu->arch.sie_block->gpsw, + sizeof(psw_t)); + rc |= read_guest_lc(vcpu, __LC_EXT_NEW_PSW, + &vcpu->arch.sie_block->gpsw, sizeof(psw_t)); + rc |= put_guest_lc(vcpu, inti->ext.ext_params, + (u32 *)__LC_EXT_PARAMS); + break; + case KVM_S390_INT_PFAULT_INIT: + trace_kvm_s390_deliver_interrupt(vcpu->vcpu_id, inti->type, 0, + inti->ext.ext_params2); + rc = put_guest_lc(vcpu, EXT_IRQ_CP_SERVICE, + (u16 *) __LC_EXT_INT_CODE); + rc |= put_guest_lc(vcpu, PFAULT_INIT, (u16 *) __LC_EXT_CPU_ADDR); + rc |= write_guest_lc(vcpu, __LC_EXT_OLD_PSW, + &vcpu->arch.sie_block->gpsw, sizeof(psw_t)); + rc |= read_guest_lc(vcpu, __LC_EXT_NEW_PSW, + &vcpu->arch.sie_block->gpsw, sizeof(psw_t)); + rc |= put_guest_lc(vcpu, inti->ext.ext_params2, + (u64 *) __LC_EXT_PARAMS2); + break; + case KVM_S390_INT_PFAULT_DONE: + trace_kvm_s390_deliver_interrupt(vcpu->vcpu_id, inti->type, 0, + inti->ext.ext_params2); + rc = put_guest_lc(vcpu, 0x2603, (u16 *)__LC_EXT_INT_CODE); + rc |= put_guest_lc(vcpu, 0x0680, (u16 *)__LC_EXT_CPU_ADDR); + rc |= write_guest_lc(vcpu, __LC_EXT_OLD_PSW, + &vcpu->arch.sie_block->gpsw, + sizeof(psw_t)); + rc |= read_guest_lc(vcpu, __LC_EXT_NEW_PSW, + &vcpu->arch.sie_block->gpsw, sizeof(psw_t)); + rc |= put_guest_lc(vcpu, inti->ext.ext_params2, + (u64 *)__LC_EXT_PARAMS2); + break; + case KVM_S390_INT_VIRTIO: + VCPU_EVENT(vcpu, 4, "interrupt: virtio parm:%x,parm64:%llx", + inti->ext.ext_params, inti->ext.ext_params2); + vcpu->stat.deliver_virtio_interrupt++; + trace_kvm_s390_deliver_interrupt(vcpu->vcpu_id, inti->type, + inti->ext.ext_params, + inti->ext.ext_params2); + rc = put_guest_lc(vcpu, 0x2603, (u16 *)__LC_EXT_INT_CODE); + rc |= put_guest_lc(vcpu, 0x0d00, (u16 *)__LC_EXT_CPU_ADDR); + rc |= write_guest_lc(vcpu, __LC_EXT_OLD_PSW, + &vcpu->arch.sie_block->gpsw, + sizeof(psw_t)); + rc |= read_guest_lc(vcpu, __LC_EXT_NEW_PSW, + &vcpu->arch.sie_block->gpsw, sizeof(psw_t)); + rc |= put_guest_lc(vcpu, inti->ext.ext_params, + (u32 *)__LC_EXT_PARAMS); + rc |= put_guest_lc(vcpu, inti->ext.ext_params2, + (u64 *)__LC_EXT_PARAMS2); + break; + case KVM_S390_SIGP_STOP: + VCPU_EVENT(vcpu, 4, "%s", "interrupt: cpu stop"); + vcpu->stat.deliver_stop_signal++; + trace_kvm_s390_deliver_interrupt(vcpu->vcpu_id, inti->type, + 0, 0); + __set_intercept_indicator(vcpu, inti); + break; + + case KVM_S390_SIGP_SET_PREFIX: + VCPU_EVENT(vcpu, 4, "interrupt: set prefix to %x", + inti->prefix.address); + vcpu->stat.deliver_prefix_signal++; + trace_kvm_s390_deliver_interrupt(vcpu->vcpu_id, inti->type, + inti->prefix.address, 0); + kvm_s390_set_prefix(vcpu, inti->prefix.address); + break; + + case KVM_S390_RESTART: + VCPU_EVENT(vcpu, 4, "%s", "interrupt: cpu restart"); + vcpu->stat.deliver_restart_signal++; + trace_kvm_s390_deliver_interrupt(vcpu->vcpu_id, inti->type, + 0, 0); + rc = write_guest_lc(vcpu, + offsetof(struct _lowcore, restart_old_psw), + &vcpu->arch.sie_block->gpsw, sizeof(psw_t)); + rc |= read_guest_lc(vcpu, offsetof(struct _lowcore, restart_psw), + &vcpu->arch.sie_block->gpsw, + sizeof(psw_t)); + break; + case KVM_S390_PROGRAM_INT: + VCPU_EVENT(vcpu, 4, "interrupt: pgm check code:%x, ilc:%x", + inti->pgm.code, + table[vcpu->arch.sie_block->ipa >> 14]); + vcpu->stat.deliver_program_int++; + trace_kvm_s390_deliver_interrupt(vcpu->vcpu_id, inti->type, + inti->pgm.code, 0); + rc = __deliver_prog_irq(vcpu, &inti->pgm); + break; + + case KVM_S390_MCHK: + VCPU_EVENT(vcpu, 4, "interrupt: machine check mcic=%llx", + inti->mchk.mcic); + trace_kvm_s390_deliver_interrupt(vcpu->vcpu_id, inti->type, + inti->mchk.cr14, + inti->mchk.mcic); + rc = kvm_s390_vcpu_store_status(vcpu, + KVM_S390_STORE_STATUS_PREFIXED); + rc |= put_guest_lc(vcpu, inti->mchk.mcic, (u64 *)__LC_MCCK_CODE); + rc |= write_guest_lc(vcpu, __LC_MCK_OLD_PSW, + &vcpu->arch.sie_block->gpsw, + sizeof(psw_t)); + rc |= read_guest_lc(vcpu, __LC_MCK_NEW_PSW, + &vcpu->arch.sie_block->gpsw, sizeof(psw_t)); + break; + + case KVM_S390_INT_IO_MIN...KVM_S390_INT_IO_MAX: + { + __u32 param0 = ((__u32)inti->io.subchannel_id << 16) | + inti->io.subchannel_nr; + __u64 param1 = ((__u64)inti->io.io_int_parm << 32) | + inti->io.io_int_word; + VCPU_EVENT(vcpu, 4, "interrupt: I/O %llx", inti->type); + vcpu->stat.deliver_io_int++; + trace_kvm_s390_deliver_interrupt(vcpu->vcpu_id, inti->type, + param0, param1); + rc = put_guest_lc(vcpu, inti->io.subchannel_id, + (u16 *)__LC_SUBCHANNEL_ID); + rc |= put_guest_lc(vcpu, inti->io.subchannel_nr, + (u16 *)__LC_SUBCHANNEL_NR); + rc |= put_guest_lc(vcpu, inti->io.io_int_parm, + (u32 *)__LC_IO_INT_PARM); + rc |= put_guest_lc(vcpu, inti->io.io_int_word, + (u32 *)__LC_IO_INT_WORD); + rc |= write_guest_lc(vcpu, __LC_IO_OLD_PSW, + &vcpu->arch.sie_block->gpsw, + sizeof(psw_t)); + rc |= read_guest_lc(vcpu, __LC_IO_NEW_PSW, + &vcpu->arch.sie_block->gpsw, + sizeof(psw_t)); + break; + } + default: + BUG(); + } + + return rc; +} + +static int __must_check deliver_ckc_interrupt(struct kvm_vcpu *vcpu) +{ + int rc; + + rc = put_guest_lc(vcpu, 0x1004, (u16 __user *)__LC_EXT_INT_CODE); + rc |= write_guest_lc(vcpu, __LC_EXT_OLD_PSW, + &vcpu->arch.sie_block->gpsw, sizeof(psw_t)); + rc |= read_guest_lc(vcpu, __LC_EXT_NEW_PSW, + &vcpu->arch.sie_block->gpsw, + sizeof(psw_t)); + return rc; +} + +/* Check whether SIGP interpretation facility has an external call pending */ +int kvm_s390_si_ext_call_pending(struct kvm_vcpu *vcpu) +{ + atomic_t *sigp_ctrl = &vcpu->kvm->arch.sca->cpu[vcpu->vcpu_id].ctrl; + + if (!psw_extint_disabled(vcpu) && + (vcpu->arch.sie_block->gcr[0] & 0x2000ul) && + (atomic_read(sigp_ctrl) & SIGP_CTRL_C) && + (atomic_read(&vcpu->arch.sie_block->cpuflags) & CPUSTAT_ECALL_PEND)) + return 1; + + return 0; +} + +int kvm_cpu_has_interrupt(struct kvm_vcpu *vcpu) +{ + struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int; + struct kvm_s390_float_interrupt *fi = vcpu->arch.local_int.float_int; + struct kvm_s390_interrupt_info *inti; + int rc = 0; + + if (atomic_read(&li->active)) { + spin_lock(&li->lock); + list_for_each_entry(inti, &li->list, list) + if (__interrupt_is_deliverable(vcpu, inti)) { + rc = 1; + break; + } + spin_unlock(&li->lock); + } + + if ((!rc) && atomic_read(&fi->active)) { + spin_lock(&fi->lock); + list_for_each_entry(inti, &fi->list, list) + if (__interrupt_is_deliverable(vcpu, inti)) { + rc = 1; + break; + } + spin_unlock(&fi->lock); + } + + if (!rc && kvm_cpu_has_pending_timer(vcpu)) + rc = 1; + + if (!rc && kvm_s390_si_ext_call_pending(vcpu)) + rc = 1; + + return rc; +} + +int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu) +{ + if (!(vcpu->arch.sie_block->ckc < + get_tod_clock_fast() + vcpu->arch.sie_block->epoch)) + return 0; + if (!ckc_interrupts_enabled(vcpu)) + return 0; + return 1; +} + +int kvm_s390_handle_wait(struct kvm_vcpu *vcpu) +{ + u64 now, sltime; + + vcpu->stat.exit_wait_state++; + + /* fast path */ + if (kvm_cpu_has_pending_timer(vcpu) || kvm_arch_vcpu_runnable(vcpu)) + return 0; + + if (psw_interrupts_disabled(vcpu)) { + VCPU_EVENT(vcpu, 3, "%s", "disabled wait"); + return -EOPNOTSUPP; /* disabled wait */ + } + + __set_cpu_idle(vcpu); + if (!ckc_interrupts_enabled(vcpu)) { + VCPU_EVENT(vcpu, 3, "%s", "enabled wait w/o timer"); + goto no_timer; + } + + now = get_tod_clock_fast() + vcpu->arch.sie_block->epoch; + sltime = tod_to_ns(vcpu->arch.sie_block->ckc - now); + hrtimer_start(&vcpu->arch.ckc_timer, ktime_set (0, sltime) , HRTIMER_MODE_REL); + VCPU_EVENT(vcpu, 5, "enabled wait via clock comparator: %llx ns", sltime); +no_timer: + srcu_read_unlock(&vcpu->kvm->srcu, vcpu->srcu_idx); + kvm_vcpu_block(vcpu); + __unset_cpu_idle(vcpu); + vcpu->srcu_idx = srcu_read_lock(&vcpu->kvm->srcu); + + hrtimer_cancel(&vcpu->arch.ckc_timer); + return 0; +} + +void kvm_s390_vcpu_wakeup(struct kvm_vcpu *vcpu) +{ + if (waitqueue_active(&vcpu->wq)) { + /* + * The vcpu gave up the cpu voluntarily, mark it as a good + * yield-candidate. + */ + vcpu->preempted = true; + wake_up_interruptible(&vcpu->wq); + vcpu->stat.halt_wakeup++; + } +} + +enum hrtimer_restart kvm_s390_idle_wakeup(struct hrtimer *timer) +{ + struct kvm_vcpu *vcpu; + u64 now, sltime; + + vcpu = container_of(timer, struct kvm_vcpu, arch.ckc_timer); + now = get_tod_clock_fast() + vcpu->arch.sie_block->epoch; + sltime = tod_to_ns(vcpu->arch.sie_block->ckc - now); + + /* + * If the monotonic clock runs faster than the tod clock we might be + * woken up too early and have to go back to sleep to avoid deadlocks. + */ + if (vcpu->arch.sie_block->ckc > now && + hrtimer_forward_now(timer, ns_to_ktime(sltime))) + return HRTIMER_RESTART; + kvm_s390_vcpu_wakeup(vcpu); + return HRTIMER_NORESTART; +} + +void kvm_s390_clear_local_irqs(struct kvm_vcpu *vcpu) +{ + struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int; + struct kvm_s390_interrupt_info *n, *inti = NULL; + + spin_lock(&li->lock); + list_for_each_entry_safe(inti, n, &li->list, list) { + list_del(&inti->list); + kfree(inti); + } + atomic_set(&li->active, 0); + spin_unlock(&li->lock); + + /* clear pending external calls set by sigp interpretation facility */ + atomic_clear_mask(CPUSTAT_ECALL_PEND, &vcpu->arch.sie_block->cpuflags); + atomic_clear_mask(SIGP_CTRL_C, + &vcpu->kvm->arch.sca->cpu[vcpu->vcpu_id].ctrl); +} + +int __must_check kvm_s390_deliver_pending_interrupts(struct kvm_vcpu *vcpu) +{ + struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int; + struct kvm_s390_float_interrupt *fi = vcpu->arch.local_int.float_int; + struct kvm_s390_interrupt_info *n, *inti = NULL; + int deliver; + int rc = 0; + + __reset_intercept_indicators(vcpu); + if (atomic_read(&li->active)) { + do { + deliver = 0; + spin_lock(&li->lock); + list_for_each_entry_safe(inti, n, &li->list, list) { + if (__interrupt_is_deliverable(vcpu, inti)) { + list_del(&inti->list); + deliver = 1; + break; + } + __set_intercept_indicator(vcpu, inti); + } + if (list_empty(&li->list)) + atomic_set(&li->active, 0); + spin_unlock(&li->lock); + if (deliver) { + rc = __do_deliver_interrupt(vcpu, inti); + kfree(inti); + } + } while (!rc && deliver); + } + + if (!rc && kvm_cpu_has_pending_timer(vcpu)) + rc = deliver_ckc_interrupt(vcpu); + + if (!rc && atomic_read(&fi->active)) { + do { + deliver = 0; + spin_lock(&fi->lock); + list_for_each_entry_safe(inti, n, &fi->list, list) { + if (__interrupt_is_deliverable(vcpu, inti)) { + list_del(&inti->list); + fi->irq_count--; + deliver = 1; + break; + } + __set_intercept_indicator(vcpu, inti); + } + if (list_empty(&fi->list)) + atomic_set(&fi->active, 0); + spin_unlock(&fi->lock); + if (deliver) { + rc = __do_deliver_interrupt(vcpu, inti); + kfree(inti); + } + } while (!rc && deliver); + } + + return rc; +} + +int kvm_s390_inject_program_int(struct kvm_vcpu *vcpu, u16 code) +{ + struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int; + struct kvm_s390_interrupt_info *inti; + + inti = kzalloc(sizeof(*inti), GFP_KERNEL); + if (!inti) + return -ENOMEM; + + inti->type = KVM_S390_PROGRAM_INT; + inti->pgm.code = code; + + VCPU_EVENT(vcpu, 3, "inject: program check %d (from kernel)", code); + trace_kvm_s390_inject_vcpu(vcpu->vcpu_id, inti->type, code, 0, 1); + spin_lock(&li->lock); + list_add(&inti->list, &li->list); + atomic_set(&li->active, 1); + BUG_ON(waitqueue_active(li->wq)); + spin_unlock(&li->lock); + return 0; +} + +int kvm_s390_inject_prog_irq(struct kvm_vcpu *vcpu, + struct kvm_s390_pgm_info *pgm_info) +{ + struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int; + struct kvm_s390_interrupt_info *inti; + + inti = kzalloc(sizeof(*inti), GFP_KERNEL); + if (!inti) + return -ENOMEM; + + VCPU_EVENT(vcpu, 3, "inject: prog irq %d (from kernel)", + pgm_info->code); + trace_kvm_s390_inject_vcpu(vcpu->vcpu_id, KVM_S390_PROGRAM_INT, + pgm_info->code, 0, 1); + + inti->type = KVM_S390_PROGRAM_INT; + memcpy(&inti->pgm, pgm_info, sizeof(inti->pgm)); + spin_lock(&li->lock); + list_add(&inti->list, &li->list); + atomic_set(&li->active, 1); + BUG_ON(waitqueue_active(li->wq)); + spin_unlock(&li->lock); + return 0; +} + +struct kvm_s390_interrupt_info *kvm_s390_get_io_int(struct kvm *kvm, + u64 cr6, u64 schid) +{ + struct kvm_s390_float_interrupt *fi; + struct kvm_s390_interrupt_info *inti, *iter; + + if ((!schid && !cr6) || (schid && cr6)) + return NULL; + fi = &kvm->arch.float_int; + spin_lock(&fi->lock); + inti = NULL; + list_for_each_entry(iter, &fi->list, list) { + if (!is_ioint(iter->type)) + continue; + if (cr6 && + ((cr6 & int_word_to_isc_bits(iter->io.io_int_word)) == 0)) + continue; + if (schid) { + if (((schid & 0x00000000ffff0000) >> 16) != + iter->io.subchannel_id) + continue; + if ((schid & 0x000000000000ffff) != + iter->io.subchannel_nr) + continue; + } + inti = iter; + break; + } + if (inti) { + list_del_init(&inti->list); + fi->irq_count--; + } + if (list_empty(&fi->list)) + atomic_set(&fi->active, 0); + spin_unlock(&fi->lock); + return inti; +} + +static int __inject_vm(struct kvm *kvm, struct kvm_s390_interrupt_info *inti) +{ + struct kvm_s390_local_interrupt *li; + struct kvm_s390_float_interrupt *fi; + struct kvm_s390_interrupt_info *iter; + struct kvm_vcpu *dst_vcpu = NULL; + int sigcpu; + int rc = 0; + + fi = &kvm->arch.float_int; + spin_lock(&fi->lock); + if (fi->irq_count >= KVM_S390_MAX_FLOAT_IRQS) { + rc = -EINVAL; + goto unlock_fi; + } + fi->irq_count++; + if (!is_ioint(inti->type)) { + list_add_tail(&inti->list, &fi->list); + } else { + u64 isc_bits = int_word_to_isc_bits(inti->io.io_int_word); + + /* Keep I/O interrupts sorted in isc order. */ + list_for_each_entry(iter, &fi->list, list) { + if (!is_ioint(iter->type)) + continue; + if (int_word_to_isc_bits(iter->io.io_int_word) + <= isc_bits) + continue; + break; + } + list_add_tail(&inti->list, &iter->list); + } + atomic_set(&fi->active, 1); + if (atomic_read(&kvm->online_vcpus) == 0) + goto unlock_fi; + sigcpu = find_first_bit(fi->idle_mask, KVM_MAX_VCPUS); + if (sigcpu == KVM_MAX_VCPUS) { + do { + sigcpu = fi->next_rr_cpu++; + if (sigcpu == KVM_MAX_VCPUS) + sigcpu = fi->next_rr_cpu = 0; + } while (kvm_get_vcpu(kvm, sigcpu) == NULL); + } + dst_vcpu = kvm_get_vcpu(kvm, sigcpu); + li = &dst_vcpu->arch.local_int; + spin_lock(&li->lock); + atomic_set_mask(CPUSTAT_EXT_INT, li->cpuflags); + spin_unlock(&li->lock); + kvm_s390_vcpu_wakeup(kvm_get_vcpu(kvm, sigcpu)); +unlock_fi: + spin_unlock(&fi->lock); + return rc; +} + +int kvm_s390_inject_vm(struct kvm *kvm, + struct kvm_s390_interrupt *s390int) +{ + struct kvm_s390_interrupt_info *inti; + int rc; + + inti = kzalloc(sizeof(*inti), GFP_KERNEL); + if (!inti) + return -ENOMEM; + + inti->type = s390int->type; + switch (inti->type) { + case KVM_S390_INT_VIRTIO: + VM_EVENT(kvm, 5, "inject: virtio parm:%x,parm64:%llx", + s390int->parm, s390int->parm64); + inti->ext.ext_params = s390int->parm; + inti->ext.ext_params2 = s390int->parm64; + break; + case KVM_S390_INT_SERVICE: + VM_EVENT(kvm, 5, "inject: sclp parm:%x", s390int->parm); + inti->ext.ext_params = s390int->parm; + break; + case KVM_S390_INT_PFAULT_DONE: + inti->type = s390int->type; + inti->ext.ext_params2 = s390int->parm64; + break; + case KVM_S390_MCHK: + VM_EVENT(kvm, 5, "inject: machine check parm64:%llx", + s390int->parm64); + inti->mchk.cr14 = s390int->parm; /* upper bits are not used */ + inti->mchk.mcic = s390int->parm64; + break; + case KVM_S390_INT_IO_MIN...KVM_S390_INT_IO_MAX: + if (inti->type & IOINT_AI_MASK) + VM_EVENT(kvm, 5, "%s", "inject: I/O (AI)"); + else + VM_EVENT(kvm, 5, "inject: I/O css %x ss %x schid %04x", + s390int->type & IOINT_CSSID_MASK, + s390int->type & IOINT_SSID_MASK, + s390int->type & IOINT_SCHID_MASK); + inti->io.subchannel_id = s390int->parm >> 16; + inti->io.subchannel_nr = s390int->parm & 0x0000ffffu; + inti->io.io_int_parm = s390int->parm64 >> 32; + inti->io.io_int_word = s390int->parm64 & 0x00000000ffffffffull; + break; + default: + kfree(inti); + return -EINVAL; + } + trace_kvm_s390_inject_vm(s390int->type, s390int->parm, s390int->parm64, + 2); + + rc = __inject_vm(kvm, inti); + if (rc) + kfree(inti); + return rc; +} + +int kvm_s390_reinject_io_int(struct kvm *kvm, + struct kvm_s390_interrupt_info *inti) +{ + return __inject_vm(kvm, inti); +} + +int kvm_s390_inject_vcpu(struct kvm_vcpu *vcpu, + struct kvm_s390_interrupt *s390int) +{ + struct kvm_s390_local_interrupt *li; + struct kvm_s390_interrupt_info *inti; + + inti = kzalloc(sizeof(*inti), GFP_KERNEL); + if (!inti) + return -ENOMEM; + + switch (s390int->type) { + case KVM_S390_PROGRAM_INT: + if (s390int->parm & 0xffff0000) { + kfree(inti); + return -EINVAL; + } + inti->type = s390int->type; + inti->pgm.code = s390int->parm; + VCPU_EVENT(vcpu, 3, "inject: program check %d (from user)", + s390int->parm); + break; + case KVM_S390_SIGP_SET_PREFIX: + inti->prefix.address = s390int->parm; + inti->type = s390int->type; + VCPU_EVENT(vcpu, 3, "inject: set prefix to %x (from user)", + s390int->parm); + break; + case KVM_S390_SIGP_STOP: + case KVM_S390_RESTART: + case KVM_S390_INT_CLOCK_COMP: + case KVM_S390_INT_CPU_TIMER: + VCPU_EVENT(vcpu, 3, "inject: type %x", s390int->type); + inti->type = s390int->type; + break; + case KVM_S390_INT_EXTERNAL_CALL: + if (s390int->parm & 0xffff0000) { + kfree(inti); + return -EINVAL; + } + VCPU_EVENT(vcpu, 3, "inject: external call source-cpu:%u", + s390int->parm); + inti->type = s390int->type; + inti->extcall.code = s390int->parm; + break; + case KVM_S390_INT_EMERGENCY: + if (s390int->parm & 0xffff0000) { + kfree(inti); + return -EINVAL; + } + VCPU_EVENT(vcpu, 3, "inject: emergency %u\n", s390int->parm); + inti->type = s390int->type; + inti->emerg.code = s390int->parm; + break; + case KVM_S390_MCHK: + VCPU_EVENT(vcpu, 5, "inject: machine check parm64:%llx", + s390int->parm64); + inti->type = s390int->type; + inti->mchk.mcic = s390int->parm64; + break; + case KVM_S390_INT_PFAULT_INIT: + inti->type = s390int->type; + inti->ext.ext_params2 = s390int->parm64; + break; + case KVM_S390_INT_VIRTIO: + case KVM_S390_INT_SERVICE: + case KVM_S390_INT_IO_MIN...KVM_S390_INT_IO_MAX: + default: + kfree(inti); + return -EINVAL; + } + trace_kvm_s390_inject_vcpu(vcpu->vcpu_id, s390int->type, s390int->parm, + s390int->parm64, 2); + + li = &vcpu->arch.local_int; + spin_lock(&li->lock); + if (inti->type == KVM_S390_PROGRAM_INT) + list_add(&inti->list, &li->list); + else + list_add_tail(&inti->list, &li->list); + atomic_set(&li->active, 1); + if (inti->type == KVM_S390_SIGP_STOP) + li->action_bits |= ACTION_STOP_ON_STOP; + atomic_set_mask(CPUSTAT_EXT_INT, li->cpuflags); + spin_unlock(&li->lock); + kvm_s390_vcpu_wakeup(vcpu); + return 0; +} + +void kvm_s390_clear_float_irqs(struct kvm *kvm) +{ + struct kvm_s390_float_interrupt *fi; + struct kvm_s390_interrupt_info *n, *inti = NULL; + + fi = &kvm->arch.float_int; + spin_lock(&fi->lock); + list_for_each_entry_safe(inti, n, &fi->list, list) { + list_del(&inti->list); + kfree(inti); + } + fi->irq_count = 0; + atomic_set(&fi->active, 0); + spin_unlock(&fi->lock); +} + +static void inti_to_irq(struct kvm_s390_interrupt_info *inti, + struct kvm_s390_irq *irq) +{ + irq->type = inti->type; + switch (inti->type) { + case KVM_S390_INT_PFAULT_INIT: + case KVM_S390_INT_PFAULT_DONE: + case KVM_S390_INT_VIRTIO: + case KVM_S390_INT_SERVICE: + irq->u.ext = inti->ext; + break; + case KVM_S390_INT_IO_MIN...KVM_S390_INT_IO_MAX: + irq->u.io = inti->io; + break; + case KVM_S390_MCHK: + irq->u.mchk = inti->mchk; + break; + } +} + +static int get_all_floating_irqs(struct kvm *kvm, u8 __user *usrbuf, u64 len) +{ + struct kvm_s390_interrupt_info *inti; + struct kvm_s390_float_interrupt *fi; + struct kvm_s390_irq *buf; + int max_irqs; + int ret = 0; + int n = 0; + + if (len > KVM_S390_FLIC_MAX_BUFFER || len == 0) + return -EINVAL; + + /* + * We are already using -ENOMEM to signal + * userspace it may retry with a bigger buffer, + * so we need to use something else for this case + */ + buf = vzalloc(len); + if (!buf) + return -ENOBUFS; + + max_irqs = len / sizeof(struct kvm_s390_irq); + + fi = &kvm->arch.float_int; + spin_lock(&fi->lock); + list_for_each_entry(inti, &fi->list, list) { + if (n == max_irqs) { + /* signal userspace to try again */ + ret = -ENOMEM; + break; + } + inti_to_irq(inti, &buf[n]); + n++; + } + spin_unlock(&fi->lock); + if (!ret && n > 0) { + if (copy_to_user(usrbuf, buf, sizeof(struct kvm_s390_irq) * n)) + ret = -EFAULT; + } + vfree(buf); + + return ret < 0 ? ret : n; +} + +static int flic_get_attr(struct kvm_device *dev, struct kvm_device_attr *attr) +{ + int r; + + switch (attr->group) { + case KVM_DEV_FLIC_GET_ALL_IRQS: + r = get_all_floating_irqs(dev->kvm, (u8 __user *) attr->addr, + attr->attr); + break; + default: + r = -EINVAL; + } + + return r; +} + +static inline int copy_irq_from_user(struct kvm_s390_interrupt_info *inti, + u64 addr) +{ + struct kvm_s390_irq __user *uptr = (struct kvm_s390_irq __user *) addr; + void *target = NULL; + void __user *source; + u64 size; + + if (get_user(inti->type, (u64 __user *)addr)) + return -EFAULT; + + switch (inti->type) { + case KVM_S390_INT_PFAULT_INIT: + case KVM_S390_INT_PFAULT_DONE: + case KVM_S390_INT_VIRTIO: + case KVM_S390_INT_SERVICE: + target = (void *) &inti->ext; + source = &uptr->u.ext; + size = sizeof(inti->ext); + break; + case KVM_S390_INT_IO_MIN...KVM_S390_INT_IO_MAX: + target = (void *) &inti->io; + source = &uptr->u.io; + size = sizeof(inti->io); + break; + case KVM_S390_MCHK: + target = (void *) &inti->mchk; + source = &uptr->u.mchk; + size = sizeof(inti->mchk); + break; + default: + return -EINVAL; + } + + if (copy_from_user(target, source, size)) + return -EFAULT; + + return 0; +} + +static int enqueue_floating_irq(struct kvm_device *dev, + struct kvm_device_attr *attr) +{ + struct kvm_s390_interrupt_info *inti = NULL; + int r = 0; + int len = attr->attr; + + if (len % sizeof(struct kvm_s390_irq) != 0) + return -EINVAL; + else if (len > KVM_S390_FLIC_MAX_BUFFER) + return -EINVAL; + + while (len >= sizeof(struct kvm_s390_irq)) { + inti = kzalloc(sizeof(*inti), GFP_KERNEL); + if (!inti) + return -ENOMEM; + + r = copy_irq_from_user(inti, attr->addr); + if (r) { + kfree(inti); + return r; + } + r = __inject_vm(dev->kvm, inti); + if (r) { + kfree(inti); + return r; + } + len -= sizeof(struct kvm_s390_irq); + attr->addr += sizeof(struct kvm_s390_irq); + } + + return r; +} + +static struct s390_io_adapter *get_io_adapter(struct kvm *kvm, unsigned int id) +{ + if (id >= MAX_S390_IO_ADAPTERS) + return NULL; + return kvm->arch.adapters[id]; +} + +static int register_io_adapter(struct kvm_device *dev, + struct kvm_device_attr *attr) +{ + struct s390_io_adapter *adapter; + struct kvm_s390_io_adapter adapter_info; + + if (copy_from_user(&adapter_info, + (void __user *)attr->addr, sizeof(adapter_info))) + return -EFAULT; + + if ((adapter_info.id >= MAX_S390_IO_ADAPTERS) || + (dev->kvm->arch.adapters[adapter_info.id] != NULL)) + return -EINVAL; + + adapter = kzalloc(sizeof(*adapter), GFP_KERNEL); + if (!adapter) + return -ENOMEM; + + INIT_LIST_HEAD(&adapter->maps); + init_rwsem(&adapter->maps_lock); + atomic_set(&adapter->nr_maps, 0); + adapter->id = adapter_info.id; + adapter->isc = adapter_info.isc; + adapter->maskable = adapter_info.maskable; + adapter->masked = false; + adapter->swap = adapter_info.swap; + dev->kvm->arch.adapters[adapter->id] = adapter; + + return 0; +} + +int kvm_s390_mask_adapter(struct kvm *kvm, unsigned int id, bool masked) +{ + int ret; + struct s390_io_adapter *adapter = get_io_adapter(kvm, id); + + if (!adapter || !adapter->maskable) + return -EINVAL; + ret = adapter->masked; + adapter->masked = masked; + return ret; +} + +static int kvm_s390_adapter_map(struct kvm *kvm, unsigned int id, __u64 addr) +{ + struct s390_io_adapter *adapter = get_io_adapter(kvm, id); + struct s390_map_info *map; + int ret; + + if (!adapter || !addr) + return -EINVAL; + + map = kzalloc(sizeof(*map), GFP_KERNEL); + if (!map) { + ret = -ENOMEM; + goto out; + } + INIT_LIST_HEAD(&map->list); + map->guest_addr = addr; + map->addr = gmap_translate(kvm->arch.gmap, addr); + if (map->addr == -EFAULT) { + ret = -EFAULT; + goto out; + } + ret = get_user_pages_fast(map->addr, 1, 1, &map->page); + if (ret < 0) + goto out; + BUG_ON(ret != 1); + down_write(&adapter->maps_lock); + if (atomic_inc_return(&adapter->nr_maps) < MAX_S390_ADAPTER_MAPS) { + list_add_tail(&map->list, &adapter->maps); + ret = 0; + } else { + put_page(map->page); + ret = -EINVAL; + } + up_write(&adapter->maps_lock); +out: + if (ret) + kfree(map); + return ret; +} + +static int kvm_s390_adapter_unmap(struct kvm *kvm, unsigned int id, __u64 addr) +{ + struct s390_io_adapter *adapter = get_io_adapter(kvm, id); + struct s390_map_info *map, *tmp; + int found = 0; + + if (!adapter || !addr) + return -EINVAL; + + down_write(&adapter->maps_lock); + list_for_each_entry_safe(map, tmp, &adapter->maps, list) { + if (map->guest_addr == addr) { + found = 1; + atomic_dec(&adapter->nr_maps); + list_del(&map->list); + put_page(map->page); + kfree(map); + break; + } + } + up_write(&adapter->maps_lock); + + return found ? 0 : -EINVAL; +} + +void kvm_s390_destroy_adapters(struct kvm *kvm) +{ + int i; + struct s390_map_info *map, *tmp; + + for (i = 0; i < MAX_S390_IO_ADAPTERS; i++) { + if (!kvm->arch.adapters[i]) + continue; + list_for_each_entry_safe(map, tmp, + &kvm->arch.adapters[i]->maps, list) { + list_del(&map->list); + put_page(map->page); + kfree(map); + } + kfree(kvm->arch.adapters[i]); + } +} + +static int modify_io_adapter(struct kvm_device *dev, + struct kvm_device_attr *attr) +{ + struct kvm_s390_io_adapter_req req; + struct s390_io_adapter *adapter; + int ret; + + if (copy_from_user(&req, (void __user *)attr->addr, sizeof(req))) + return -EFAULT; + + adapter = get_io_adapter(dev->kvm, req.id); + if (!adapter) + return -EINVAL; + switch (req.type) { + case KVM_S390_IO_ADAPTER_MASK: + ret = kvm_s390_mask_adapter(dev->kvm, req.id, req.mask); + if (ret > 0) + ret = 0; + break; + case KVM_S390_IO_ADAPTER_MAP: + ret = kvm_s390_adapter_map(dev->kvm, req.id, req.addr); + break; + case KVM_S390_IO_ADAPTER_UNMAP: + ret = kvm_s390_adapter_unmap(dev->kvm, req.id, req.addr); + break; + default: + ret = -EINVAL; + } + + return ret; +} + +static int flic_set_attr(struct kvm_device *dev, struct kvm_device_attr *attr) +{ + int r = 0; + unsigned int i; + struct kvm_vcpu *vcpu; + + switch (attr->group) { + case KVM_DEV_FLIC_ENQUEUE: + r = enqueue_floating_irq(dev, attr); + break; + case KVM_DEV_FLIC_CLEAR_IRQS: + kvm_s390_clear_float_irqs(dev->kvm); + break; + case KVM_DEV_FLIC_APF_ENABLE: + dev->kvm->arch.gmap->pfault_enabled = 1; + break; + case KVM_DEV_FLIC_APF_DISABLE_WAIT: + dev->kvm->arch.gmap->pfault_enabled = 0; + /* + * Make sure no async faults are in transition when + * clearing the queues. So we don't need to worry + * about late coming workers. + */ + synchronize_srcu(&dev->kvm->srcu); + kvm_for_each_vcpu(i, vcpu, dev->kvm) + kvm_clear_async_pf_completion_queue(vcpu); + break; + case KVM_DEV_FLIC_ADAPTER_REGISTER: + r = register_io_adapter(dev, attr); + break; + case KVM_DEV_FLIC_ADAPTER_MODIFY: + r = modify_io_adapter(dev, attr); + break; + default: + r = -EINVAL; + } + + return r; +} + +static int flic_create(struct kvm_device *dev, u32 type) +{ + if (!dev) + return -EINVAL; + if (dev->kvm->arch.flic) + return -EINVAL; + dev->kvm->arch.flic = dev; + return 0; +} + +static void flic_destroy(struct kvm_device *dev) +{ + dev->kvm->arch.flic = NULL; + kfree(dev); +} + +/* s390 floating irq controller (flic) */ +struct kvm_device_ops kvm_flic_ops = { + .name = "kvm-flic", + .get_attr = flic_get_attr, + .set_attr = flic_set_attr, + .create = flic_create, + .destroy = flic_destroy, +}; + +static unsigned long get_ind_bit(__u64 addr, unsigned long bit_nr, bool swap) +{ + unsigned long bit; + + bit = bit_nr + (addr % PAGE_SIZE) * 8; + + return swap ? (bit ^ (BITS_PER_LONG - 1)) : bit; +} + +static struct s390_map_info *get_map_info(struct s390_io_adapter *adapter, + u64 addr) +{ + struct s390_map_info *map; + + if (!adapter) + return NULL; + + list_for_each_entry(map, &adapter->maps, list) { + if (map->guest_addr == addr) + return map; + } + return NULL; +} + +static int adapter_indicators_set(struct kvm *kvm, + struct s390_io_adapter *adapter, + struct kvm_s390_adapter_int *adapter_int) +{ + unsigned long bit; + int summary_set, idx; + struct s390_map_info *info; + void *map; + + info = get_map_info(adapter, adapter_int->ind_addr); + if (!info) + return -1; + map = page_address(info->page); + bit = get_ind_bit(info->addr, adapter_int->ind_offset, adapter->swap); + set_bit(bit, map); + idx = srcu_read_lock(&kvm->srcu); + mark_page_dirty(kvm, info->guest_addr >> PAGE_SHIFT); + set_page_dirty_lock(info->page); + info = get_map_info(adapter, adapter_int->summary_addr); + if (!info) { + srcu_read_unlock(&kvm->srcu, idx); + return -1; + } + map = page_address(info->page); + bit = get_ind_bit(info->addr, adapter_int->summary_offset, + adapter->swap); + summary_set = test_and_set_bit(bit, map); + mark_page_dirty(kvm, info->guest_addr >> PAGE_SHIFT); + set_page_dirty_lock(info->page); + srcu_read_unlock(&kvm->srcu, idx); + return summary_set ? 0 : 1; +} + +/* + * < 0 - not injected due to error + * = 0 - coalesced, summary indicator already active + * > 0 - injected interrupt + */ +static int set_adapter_int(struct kvm_kernel_irq_routing_entry *e, + struct kvm *kvm, int irq_source_id, int level, + bool line_status) +{ + int ret; + struct s390_io_adapter *adapter; + + /* We're only interested in the 0->1 transition. */ + if (!level) + return 0; + adapter = get_io_adapter(kvm, e->adapter.adapter_id); + if (!adapter) + return -1; + down_read(&adapter->maps_lock); + ret = adapter_indicators_set(kvm, adapter, &e->adapter); + up_read(&adapter->maps_lock); + if ((ret > 0) && !adapter->masked) { + struct kvm_s390_interrupt s390int = { + .type = KVM_S390_INT_IO(1, 0, 0, 0), + .parm = 0, + .parm64 = (adapter->isc << 27) | 0x80000000, + }; + ret = kvm_s390_inject_vm(kvm, &s390int); + if (ret == 0) + ret = 1; + } + return ret; +} + +int kvm_set_routing_entry(struct kvm_kernel_irq_routing_entry *e, + const struct kvm_irq_routing_entry *ue) +{ + int ret; + + switch (ue->type) { + case KVM_IRQ_ROUTING_S390_ADAPTER: + e->set = set_adapter_int; + e->adapter.summary_addr = ue->u.adapter.summary_addr; + e->adapter.ind_addr = ue->u.adapter.ind_addr; + e->adapter.summary_offset = ue->u.adapter.summary_offset; + e->adapter.ind_offset = ue->u.adapter.ind_offset; + e->adapter.adapter_id = ue->u.adapter.adapter_id; + ret = 0; + break; + default: + ret = -EINVAL; + } + + return ret; +} + +int kvm_set_msi(struct kvm_kernel_irq_routing_entry *e, struct kvm *kvm, + int irq_source_id, int level, bool line_status) +{ + return -EINVAL; +} diff -Nur linux-3.18.14.orig/arch/s390/mm/fault.c linux-3.18.14-rt/arch/s390/mm/fault.c --- linux-3.18.14.orig/arch/s390/mm/fault.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/s390/mm/fault.c 2015-05-31 15:32:46.401635385 -0500 @@ -435,7 +435,8 @@ * user context. */ fault = VM_FAULT_BADCONTEXT; - if (unlikely(!user_space_fault(regs) || in_atomic() || !mm)) + if (unlikely(!user_space_fault(regs) || !mm || + tsk->pagefault_disabled)) goto out; address = trans_exc_code & __FAIL_ADDR_MASK; diff -Nur linux-3.18.14.orig/arch/score/mm/fault.c linux-3.18.14-rt/arch/score/mm/fault.c --- linux-3.18.14.orig/arch/score/mm/fault.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/score/mm/fault.c 2015-05-31 15:32:46.413635385 -0500 @@ -73,7 +73,7 @@ * If we're in an interrupt or have no user * context, we must not take the fault.. */ - if (in_atomic() || !mm) + if (!mm || pagefault_disabled()) goto bad_area_nosemaphore; if (user_mode(regs)) diff -Nur linux-3.18.14.orig/arch/sh/kernel/irq.c linux-3.18.14-rt/arch/sh/kernel/irq.c --- linux-3.18.14.orig/arch/sh/kernel/irq.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/sh/kernel/irq.c 2015-05-31 15:32:46.429635385 -0500 @@ -149,6 +149,7 @@ hardirq_ctx[cpu] = NULL; } +#ifndef CONFIG_PREEMPT_RT_FULL void do_softirq_own_stack(void) { struct thread_info *curctx; @@ -176,6 +177,7 @@ "r5", "r6", "r7", "r8", "r9", "r15", "t", "pr" ); } +#endif #else static inline void handle_one_irq(unsigned int irq) { diff -Nur linux-3.18.14.orig/arch/sh/mm/fault.c linux-3.18.14-rt/arch/sh/mm/fault.c --- linux-3.18.14.orig/arch/sh/mm/fault.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/sh/mm/fault.c 2015-05-31 15:32:46.469635385 -0500 @@ -440,7 +440,7 @@ * If we're in an interrupt, have no user context or are running * in an atomic region then we must not take the fault: */ - if (unlikely(in_atomic() || !mm)) { + if (unlikely(!mm || pagefault_disabled())) { bad_area_nosemaphore(regs, error_code, address); return; } diff -Nur linux-3.18.14.orig/arch/sparc/Kconfig linux-3.18.14-rt/arch/sparc/Kconfig --- linux-3.18.14.orig/arch/sparc/Kconfig 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/sparc/Kconfig 2015-05-31 15:32:46.469635385 -0500 @@ -182,12 +182,10 @@ source kernel/Kconfig.hz config RWSEM_GENERIC_SPINLOCK - bool - default y if SPARC32 + def_bool PREEMPT_RT_FULL config RWSEM_XCHGADD_ALGORITHM - bool - default y if SPARC64 + def_bool !RWSEM_GENERIC_SPINLOCK && !PREEMPT_RT_FULL config GENERIC_HWEIGHT bool @@ -528,6 +526,10 @@ source "fs/Kconfig.binfmt" +config EARLY_PRINTK + bool + default y + config COMPAT bool depends on SPARC64 diff -Nur linux-3.18.14.orig/arch/sparc/kernel/irq_64.c linux-3.18.14-rt/arch/sparc/kernel/irq_64.c --- linux-3.18.14.orig/arch/sparc/kernel/irq_64.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/sparc/kernel/irq_64.c 2015-05-31 15:32:46.477635385 -0500 @@ -849,6 +849,7 @@ set_irq_regs(old_regs); } +#ifndef CONFIG_PREEMPT_RT_FULL void do_softirq_own_stack(void) { void *orig_sp, *sp = softirq_stack[smp_processor_id()]; @@ -863,6 +864,7 @@ __asm__ __volatile__("mov %0, %%sp" : : "r" (orig_sp)); } +#endif #ifdef CONFIG_HOTPLUG_CPU void fixup_irqs(void) diff -Nur linux-3.18.14.orig/arch/sparc/kernel/setup_32.c linux-3.18.14-rt/arch/sparc/kernel/setup_32.c --- linux-3.18.14.orig/arch/sparc/kernel/setup_32.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/sparc/kernel/setup_32.c 2015-05-31 15:32:46.489635385 -0500 @@ -309,6 +309,7 @@ boot_flags_init(*cmdline_p); + early_console = &prom_early_console; register_console(&prom_early_console); printk("ARCH: "); diff -Nur linux-3.18.14.orig/arch/sparc/kernel/setup_64.c linux-3.18.14-rt/arch/sparc/kernel/setup_64.c --- linux-3.18.14.orig/arch/sparc/kernel/setup_64.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/sparc/kernel/setup_64.c 2015-05-31 15:32:46.509635384 -0500 @@ -563,6 +563,12 @@ pause_patch(); } +static inline void register_prom_console(void) +{ + early_console = &prom_early_console; + register_console(&prom_early_console); +} + void __init setup_arch(char **cmdline_p) { /* Initialize PROM console and command line. */ @@ -574,7 +580,7 @@ #ifdef CONFIG_EARLYFB if (btext_find_display()) #endif - register_console(&prom_early_console); + register_prom_console(); if (tlb_type == hypervisor) printk("ARCH: SUN4V\n"); diff -Nur linux-3.18.14.orig/arch/sparc/mm/fault_32.c linux-3.18.14-rt/arch/sparc/mm/fault_32.c --- linux-3.18.14.orig/arch/sparc/mm/fault_32.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/sparc/mm/fault_32.c 2015-05-31 15:32:46.529635385 -0500 @@ -196,7 +196,7 @@ * If we're in an interrupt or have no user * context, we must not take the fault.. */ - if (in_atomic() || !mm) + if (!mm || pagefault_disabled()) goto no_context; perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address); diff -Nur linux-3.18.14.orig/arch/sparc/mm/fault_64.c linux-3.18.14-rt/arch/sparc/mm/fault_64.c --- linux-3.18.14.orig/arch/sparc/mm/fault_64.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/sparc/mm/fault_64.c 2015-05-31 15:32:46.529635385 -0500 @@ -330,7 +330,7 @@ * If we're in an interrupt or have no user * context, we must not take the fault.. */ - if (in_atomic() || !mm) + if (!mm || pagefault_disabled()) goto intr_or_no_mm; perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address); diff -Nur linux-3.18.14.orig/arch/tile/mm/fault.c linux-3.18.14-rt/arch/tile/mm/fault.c --- linux-3.18.14.orig/arch/tile/mm/fault.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/tile/mm/fault.c 2015-05-31 15:32:46.533635385 -0500 @@ -357,7 +357,7 @@ * If we're in an interrupt, have no user context or are running in an * atomic region then we must not take the fault. */ - if (in_atomic() || !mm) { + if (!mm || pagefault_disabled()) { vma = NULL; /* happy compiler */ goto bad_area_nosemaphore; } diff -Nur linux-3.18.14.orig/arch/um/kernel/trap.c linux-3.18.14-rt/arch/um/kernel/trap.c --- linux-3.18.14.orig/arch/um/kernel/trap.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/um/kernel/trap.c 2015-05-31 15:32:46.537635384 -0500 @@ -38,7 +38,7 @@ * If the fault was during atomic operation, don't take the fault, just * fail. */ - if (in_atomic()) + if (pagefault_disabled()) goto out_nosemaphore; if (is_user) diff -Nur linux-3.18.14.orig/arch/x86/crypto/aesni-intel_glue.c linux-3.18.14-rt/arch/x86/crypto/aesni-intel_glue.c --- linux-3.18.14.orig/arch/x86/crypto/aesni-intel_glue.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/x86/crypto/aesni-intel_glue.c 2015-05-31 15:32:46.569635384 -0500 @@ -381,14 +381,14 @@ err = blkcipher_walk_virt(desc, &walk); desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP; - kernel_fpu_begin(); while ((nbytes = walk.nbytes)) { + kernel_fpu_begin(); aesni_ecb_enc(ctx, walk.dst.virt.addr, walk.src.virt.addr, - nbytes & AES_BLOCK_MASK); + nbytes & AES_BLOCK_MASK); + kernel_fpu_end(); nbytes &= AES_BLOCK_SIZE - 1; err = blkcipher_walk_done(desc, &walk, nbytes); } - kernel_fpu_end(); return err; } @@ -405,14 +405,14 @@ err = blkcipher_walk_virt(desc, &walk); desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP; - kernel_fpu_begin(); while ((nbytes = walk.nbytes)) { + kernel_fpu_begin(); aesni_ecb_dec(ctx, walk.dst.virt.addr, walk.src.virt.addr, nbytes & AES_BLOCK_MASK); + kernel_fpu_end(); nbytes &= AES_BLOCK_SIZE - 1; err = blkcipher_walk_done(desc, &walk, nbytes); } - kernel_fpu_end(); return err; } @@ -429,14 +429,14 @@ err = blkcipher_walk_virt(desc, &walk); desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP; - kernel_fpu_begin(); while ((nbytes = walk.nbytes)) { + kernel_fpu_begin(); aesni_cbc_enc(ctx, walk.dst.virt.addr, walk.src.virt.addr, nbytes & AES_BLOCK_MASK, walk.iv); + kernel_fpu_end(); nbytes &= AES_BLOCK_SIZE - 1; err = blkcipher_walk_done(desc, &walk, nbytes); } - kernel_fpu_end(); return err; } @@ -453,14 +453,14 @@ err = blkcipher_walk_virt(desc, &walk); desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP; - kernel_fpu_begin(); while ((nbytes = walk.nbytes)) { + kernel_fpu_begin(); aesni_cbc_dec(ctx, walk.dst.virt.addr, walk.src.virt.addr, nbytes & AES_BLOCK_MASK, walk.iv); + kernel_fpu_end(); nbytes &= AES_BLOCK_SIZE - 1; err = blkcipher_walk_done(desc, &walk, nbytes); } - kernel_fpu_end(); return err; } @@ -512,18 +512,20 @@ err = blkcipher_walk_virt_block(desc, &walk, AES_BLOCK_SIZE); desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP; - kernel_fpu_begin(); while ((nbytes = walk.nbytes) >= AES_BLOCK_SIZE) { + kernel_fpu_begin(); aesni_ctr_enc_tfm(ctx, walk.dst.virt.addr, walk.src.virt.addr, nbytes & AES_BLOCK_MASK, walk.iv); + kernel_fpu_end(); nbytes &= AES_BLOCK_SIZE - 1; err = blkcipher_walk_done(desc, &walk, nbytes); } if (walk.nbytes) { + kernel_fpu_begin(); ctr_crypt_final(ctx, &walk); + kernel_fpu_end(); err = blkcipher_walk_done(desc, &walk, 0); } - kernel_fpu_end(); return err; } diff -Nur linux-3.18.14.orig/arch/x86/crypto/cast5_avx_glue.c linux-3.18.14-rt/arch/x86/crypto/cast5_avx_glue.c --- linux-3.18.14.orig/arch/x86/crypto/cast5_avx_glue.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/x86/crypto/cast5_avx_glue.c 2015-05-31 15:32:46.585635384 -0500 @@ -60,7 +60,7 @@ static int ecb_crypt(struct blkcipher_desc *desc, struct blkcipher_walk *walk, bool enc) { - bool fpu_enabled = false; + bool fpu_enabled; struct cast5_ctx *ctx = crypto_blkcipher_ctx(desc->tfm); const unsigned int bsize = CAST5_BLOCK_SIZE; unsigned int nbytes; @@ -76,7 +76,7 @@ u8 *wsrc = walk->src.virt.addr; u8 *wdst = walk->dst.virt.addr; - fpu_enabled = cast5_fpu_begin(fpu_enabled, nbytes); + fpu_enabled = cast5_fpu_begin(false, nbytes); /* Process multi-block batch */ if (nbytes >= bsize * CAST5_PARALLEL_BLOCKS) { @@ -104,10 +104,9 @@ } while (nbytes >= bsize); done: + cast5_fpu_end(fpu_enabled); err = blkcipher_walk_done(desc, walk, nbytes); } - - cast5_fpu_end(fpu_enabled); return err; } @@ -228,7 +227,7 @@ static int cbc_decrypt(struct blkcipher_desc *desc, struct scatterlist *dst, struct scatterlist *src, unsigned int nbytes) { - bool fpu_enabled = false; + bool fpu_enabled; struct blkcipher_walk walk; int err; @@ -237,12 +236,11 @@ desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP; while ((nbytes = walk.nbytes)) { - fpu_enabled = cast5_fpu_begin(fpu_enabled, nbytes); + fpu_enabled = cast5_fpu_begin(false, nbytes); nbytes = __cbc_decrypt(desc, &walk); + cast5_fpu_end(fpu_enabled); err = blkcipher_walk_done(desc, &walk, nbytes); } - - cast5_fpu_end(fpu_enabled); return err; } @@ -312,7 +310,7 @@ static int ctr_crypt(struct blkcipher_desc *desc, struct scatterlist *dst, struct scatterlist *src, unsigned int nbytes) { - bool fpu_enabled = false; + bool fpu_enabled; struct blkcipher_walk walk; int err; @@ -321,13 +319,12 @@ desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP; while ((nbytes = walk.nbytes) >= CAST5_BLOCK_SIZE) { - fpu_enabled = cast5_fpu_begin(fpu_enabled, nbytes); + fpu_enabled = cast5_fpu_begin(false, nbytes); nbytes = __ctr_crypt(desc, &walk); + cast5_fpu_end(fpu_enabled); err = blkcipher_walk_done(desc, &walk, nbytes); } - cast5_fpu_end(fpu_enabled); - if (walk.nbytes) { ctr_crypt_final(desc, &walk); err = blkcipher_walk_done(desc, &walk, 0); diff -Nur linux-3.18.14.orig/arch/x86/crypto/glue_helper.c linux-3.18.14-rt/arch/x86/crypto/glue_helper.c --- linux-3.18.14.orig/arch/x86/crypto/glue_helper.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/x86/crypto/glue_helper.c 2015-05-31 15:32:46.589635384 -0500 @@ -39,7 +39,7 @@ void *ctx = crypto_blkcipher_ctx(desc->tfm); const unsigned int bsize = 128 / 8; unsigned int nbytes, i, func_bytes; - bool fpu_enabled = false; + bool fpu_enabled; int err; err = blkcipher_walk_virt(desc, walk); @@ -49,7 +49,7 @@ u8 *wdst = walk->dst.virt.addr; fpu_enabled = glue_fpu_begin(bsize, gctx->fpu_blocks_limit, - desc, fpu_enabled, nbytes); + desc, false, nbytes); for (i = 0; i < gctx->num_funcs; i++) { func_bytes = bsize * gctx->funcs[i].num_blocks; @@ -71,10 +71,10 @@ } done: + glue_fpu_end(fpu_enabled); err = blkcipher_walk_done(desc, walk, nbytes); } - glue_fpu_end(fpu_enabled); return err; } @@ -194,7 +194,7 @@ struct scatterlist *src, unsigned int nbytes) { const unsigned int bsize = 128 / 8; - bool fpu_enabled = false; + bool fpu_enabled; struct blkcipher_walk walk; int err; @@ -203,12 +203,12 @@ while ((nbytes = walk.nbytes)) { fpu_enabled = glue_fpu_begin(bsize, gctx->fpu_blocks_limit, - desc, fpu_enabled, nbytes); + desc, false, nbytes); nbytes = __glue_cbc_decrypt_128bit(gctx, desc, &walk); + glue_fpu_end(fpu_enabled); err = blkcipher_walk_done(desc, &walk, nbytes); } - glue_fpu_end(fpu_enabled); return err; } EXPORT_SYMBOL_GPL(glue_cbc_decrypt_128bit); @@ -278,7 +278,7 @@ struct scatterlist *src, unsigned int nbytes) { const unsigned int bsize = 128 / 8; - bool fpu_enabled = false; + bool fpu_enabled; struct blkcipher_walk walk; int err; @@ -287,13 +287,12 @@ while ((nbytes = walk.nbytes) >= bsize) { fpu_enabled = glue_fpu_begin(bsize, gctx->fpu_blocks_limit, - desc, fpu_enabled, nbytes); + desc, false, nbytes); nbytes = __glue_ctr_crypt_128bit(gctx, desc, &walk); + glue_fpu_end(fpu_enabled); err = blkcipher_walk_done(desc, &walk, nbytes); } - glue_fpu_end(fpu_enabled); - if (walk.nbytes) { glue_ctr_crypt_final_128bit( gctx->funcs[gctx->num_funcs - 1].fn_u.ctr, desc, &walk); @@ -348,7 +347,7 @@ void *tweak_ctx, void *crypt_ctx) { const unsigned int bsize = 128 / 8; - bool fpu_enabled = false; + bool fpu_enabled; struct blkcipher_walk walk; int err; @@ -361,21 +360,21 @@ /* set minimum length to bsize, for tweak_fn */ fpu_enabled = glue_fpu_begin(bsize, gctx->fpu_blocks_limit, - desc, fpu_enabled, + desc, false, nbytes < bsize ? bsize : nbytes); - /* calculate first value of T */ tweak_fn(tweak_ctx, walk.iv, walk.iv); + glue_fpu_end(fpu_enabled); while (nbytes) { + fpu_enabled = glue_fpu_begin(bsize, gctx->fpu_blocks_limit, + desc, false, nbytes); nbytes = __glue_xts_crypt_128bit(gctx, crypt_ctx, desc, &walk); + glue_fpu_end(fpu_enabled); err = blkcipher_walk_done(desc, &walk, nbytes); nbytes = walk.nbytes; } - - glue_fpu_end(fpu_enabled); - return err; } EXPORT_SYMBOL_GPL(glue_xts_crypt_128bit); diff -Nur linux-3.18.14.orig/arch/x86/include/asm/preempt.h linux-3.18.14-rt/arch/x86/include/asm/preempt.h --- linux-3.18.14.orig/arch/x86/include/asm/preempt.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/x86/include/asm/preempt.h 2015-05-31 15:32:46.597635384 -0500 @@ -85,17 +85,33 @@ * a decrement which hits zero means we have no preempt_count and should * reschedule. */ -static __always_inline bool __preempt_count_dec_and_test(void) +static __always_inline bool ____preempt_count_dec_and_test(void) { GEN_UNARY_RMWcc("decl", __preempt_count, __percpu_arg(0), "e"); } +static __always_inline bool __preempt_count_dec_and_test(void) +{ + if (____preempt_count_dec_and_test()) + return true; +#ifdef CONFIG_PREEMPT_LAZY + return test_thread_flag(TIF_NEED_RESCHED_LAZY); +#else + return false; +#endif +} + /* * Returns true when we need to resched and can (barring IRQ state). */ static __always_inline bool should_resched(void) { +#ifdef CONFIG_PREEMPT_LAZY + return unlikely(!raw_cpu_read_4(__preempt_count) || \ + test_thread_flag(TIF_NEED_RESCHED_LAZY)); +#else return unlikely(!raw_cpu_read_4(__preempt_count)); +#endif } #ifdef CONFIG_PREEMPT diff -Nur linux-3.18.14.orig/arch/x86/include/asm/signal.h linux-3.18.14-rt/arch/x86/include/asm/signal.h --- linux-3.18.14.orig/arch/x86/include/asm/signal.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/x86/include/asm/signal.h 2015-05-31 15:32:46.597635384 -0500 @@ -23,6 +23,19 @@ unsigned long sig[_NSIG_WORDS]; } sigset_t; +/* + * Because some traps use the IST stack, we must keep preemption + * disabled while calling do_trap(), but do_trap() may call + * force_sig_info() which will grab the signal spin_locks for the + * task, which in PREEMPT_RT_FULL are mutexes. By defining + * ARCH_RT_DELAYS_SIGNAL_SEND the force_sig_info() will set + * TIF_NOTIFY_RESUME and set up the signal to be sent on exit of the + * trap. + */ +#if defined(CONFIG_PREEMPT_RT_FULL) && defined(CONFIG_X86_64) +#define ARCH_RT_DELAYS_SIGNAL_SEND +#endif + #ifndef CONFIG_COMPAT typedef sigset_t compat_sigset_t; #endif diff -Nur linux-3.18.14.orig/arch/x86/include/asm/stackprotector.h linux-3.18.14-rt/arch/x86/include/asm/stackprotector.h --- linux-3.18.14.orig/arch/x86/include/asm/stackprotector.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/x86/include/asm/stackprotector.h 2015-05-31 15:32:46.613635384 -0500 @@ -57,7 +57,7 @@ */ static __always_inline void boot_init_stack_canary(void) { - u64 canary; + u64 uninitialized_var(canary); u64 tsc; #ifdef CONFIG_X86_64 @@ -68,8 +68,16 @@ * of randomness. The TSC only matters for very early init, * there it already has some randomness on most systems. Later * on during the bootup the random pool has true entropy too. + * + * For preempt-rt we need to weaken the randomness a bit, as + * we can't call into the random generator from atomic context + * due to locking constraints. We just leave canary + * uninitialized and use the TSC based randomness on top of + * it. */ +#ifndef CONFIG_PREEMPT_RT_FULL get_random_bytes(&canary, sizeof(canary)); +#endif tsc = __native_read_tsc(); canary += tsc + (tsc << 32UL); diff -Nur linux-3.18.14.orig/arch/x86/include/asm/thread_info.h linux-3.18.14-rt/arch/x86/include/asm/thread_info.h --- linux-3.18.14.orig/arch/x86/include/asm/thread_info.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/x86/include/asm/thread_info.h 2015-05-31 15:32:46.621635383 -0500 @@ -30,6 +30,8 @@ __u32 status; /* thread synchronous flags */ __u32 cpu; /* current CPU */ int saved_preempt_count; + int preempt_lazy_count; /* 0 => lazy preemptable + <0 => BUG */ mm_segment_t addr_limit; struct restart_block restart_block; void __user *sysenter_return; @@ -75,6 +77,7 @@ #define TIF_SYSCALL_EMU 6 /* syscall emulation active */ #define TIF_SYSCALL_AUDIT 7 /* syscall auditing active */ #define TIF_SECCOMP 8 /* secure computing */ +#define TIF_NEED_RESCHED_LAZY 9 /* lazy rescheduling necessary */ #define TIF_MCE_NOTIFY 10 /* notify userspace of an MCE */ #define TIF_USER_RETURN_NOTIFY 11 /* notify kernel of userspace return */ #define TIF_UPROBE 12 /* breakpointed or singlestepping */ @@ -100,6 +103,7 @@ #define _TIF_SYSCALL_EMU (1 << TIF_SYSCALL_EMU) #define _TIF_SYSCALL_AUDIT (1 << TIF_SYSCALL_AUDIT) #define _TIF_SECCOMP (1 << TIF_SECCOMP) +#define _TIF_NEED_RESCHED_LAZY (1 << TIF_NEED_RESCHED_LAZY) #define _TIF_MCE_NOTIFY (1 << TIF_MCE_NOTIFY) #define _TIF_USER_RETURN_NOTIFY (1 << TIF_USER_RETURN_NOTIFY) #define _TIF_UPROBE (1 << TIF_UPROBE) @@ -150,6 +154,8 @@ #define _TIF_WORK_CTXSW_PREV (_TIF_WORK_CTXSW|_TIF_USER_RETURN_NOTIFY) #define _TIF_WORK_CTXSW_NEXT (_TIF_WORK_CTXSW) +#define _TIF_NEED_RESCHED_MASK (_TIF_NEED_RESCHED | _TIF_NEED_RESCHED_LAZY) + #define STACK_WARN (THREAD_SIZE/8) #define KERNEL_STACK_OFFSET (5*(BITS_PER_LONG/8)) diff -Nur linux-3.18.14.orig/arch/x86/include/asm/uv/uv_bau.h linux-3.18.14-rt/arch/x86/include/asm/uv/uv_bau.h --- linux-3.18.14.orig/arch/x86/include/asm/uv/uv_bau.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/x86/include/asm/uv/uv_bau.h 2015-05-31 15:32:46.621635383 -0500 @@ -615,9 +615,9 @@ cycles_t send_message; cycles_t period_end; cycles_t period_time; - spinlock_t uvhub_lock; - spinlock_t queue_lock; - spinlock_t disable_lock; + raw_spinlock_t uvhub_lock; + raw_spinlock_t queue_lock; + raw_spinlock_t disable_lock; /* tunables */ int max_concurr; int max_concurr_const; @@ -776,15 +776,15 @@ * to be lowered below the current 'v'. atomic_add_unless can only stop * on equal. */ -static inline int atomic_inc_unless_ge(spinlock_t *lock, atomic_t *v, int u) +static inline int atomic_inc_unless_ge(raw_spinlock_t *lock, atomic_t *v, int u) { - spin_lock(lock); + raw_spin_lock(lock); if (atomic_read(v) >= u) { - spin_unlock(lock); + raw_spin_unlock(lock); return 0; } atomic_inc(v); - spin_unlock(lock); + raw_spin_unlock(lock); return 1; } diff -Nur linux-3.18.14.orig/arch/x86/include/asm/uv/uv_hub.h linux-3.18.14-rt/arch/x86/include/asm/uv/uv_hub.h --- linux-3.18.14.orig/arch/x86/include/asm/uv/uv_hub.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/x86/include/asm/uv/uv_hub.h 2015-05-31 15:32:46.621635383 -0500 @@ -492,7 +492,7 @@ unsigned short nr_online_cpus; unsigned short pnode; short memory_nid; - spinlock_t nmi_lock; /* obsolete, see uv_hub_nmi */ + raw_spinlock_t nmi_lock; /* obsolete, see uv_hub_nmi */ unsigned long nmi_count; /* obsolete, see uv_hub_nmi */ }; extern struct uv_blade_info *uv_blade_info; diff -Nur linux-3.18.14.orig/arch/x86/Kconfig linux-3.18.14-rt/arch/x86/Kconfig --- linux-3.18.14.orig/arch/x86/Kconfig 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/x86/Kconfig 2015-05-31 15:32:46.561635384 -0500 @@ -21,6 +21,7 @@ ### Arch settings config X86 def_bool y + select HAVE_PREEMPT_LAZY select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI select ARCH_HAS_DEBUG_STRICT_USER_COPY_CHECKS select ARCH_HAS_FAST_MULTIPLIER @@ -197,8 +198,11 @@ def_bool y depends on ISA_DMA_API +config RWSEM_GENERIC_SPINLOCK + def_bool PREEMPT_RT_FULL + config RWSEM_XCHGADD_ALGORITHM - def_bool y + def_bool !RWSEM_GENERIC_SPINLOCK && !PREEMPT_RT_FULL config GENERIC_CALIBRATE_DELAY def_bool y @@ -811,7 +815,7 @@ config MAXSMP bool "Enable Maximum number of SMP Processors and NUMA Nodes" depends on X86_64 && SMP && DEBUG_KERNEL - select CPUMASK_OFFSTACK + select CPUMASK_OFFSTACK if !PREEMPT_RT_FULL ---help--- Enable maximum number of CPUS and NUMA Nodes for this architecture. If unsure, say N. diff -Nur linux-3.18.14.orig/arch/x86/kernel/apic/io_apic.c linux-3.18.14-rt/arch/x86/kernel/apic/io_apic.c --- linux-3.18.14.orig/arch/x86/kernel/apic/io_apic.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/x86/kernel/apic/io_apic.c 2015-05-31 15:32:46.629635384 -0500 @@ -2494,7 +2494,8 @@ static inline bool ioapic_irqd_mask(struct irq_data *data, struct irq_cfg *cfg) { /* If we are moving the irq we need to mask it */ - if (unlikely(irqd_is_setaffinity_pending(data))) { + if (unlikely(irqd_is_setaffinity_pending(data) && + !irqd_irq_inprogress(data))) { mask_ioapic(cfg); return true; } diff -Nur linux-3.18.14.orig/arch/x86/kernel/apic/x2apic_uv_x.c linux-3.18.14-rt/arch/x86/kernel/apic/x2apic_uv_x.c --- linux-3.18.14.orig/arch/x86/kernel/apic/x2apic_uv_x.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/x86/kernel/apic/x2apic_uv_x.c 2015-05-31 15:32:46.629635384 -0500 @@ -918,7 +918,7 @@ uv_blade_info[blade].pnode = pnode; uv_blade_info[blade].nr_possible_cpus = 0; uv_blade_info[blade].nr_online_cpus = 0; - spin_lock_init(&uv_blade_info[blade].nmi_lock); + raw_spin_lock_init(&uv_blade_info[blade].nmi_lock); min_pnode = min(pnode, min_pnode); max_pnode = max(pnode, max_pnode); blade++; diff -Nur linux-3.18.14.orig/arch/x86/kernel/asm-offsets.c linux-3.18.14-rt/arch/x86/kernel/asm-offsets.c --- linux-3.18.14.orig/arch/x86/kernel/asm-offsets.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/x86/kernel/asm-offsets.c 2015-05-31 15:32:46.633635383 -0500 @@ -32,6 +32,7 @@ OFFSET(TI_flags, thread_info, flags); OFFSET(TI_status, thread_info, status); OFFSET(TI_addr_limit, thread_info, addr_limit); + OFFSET(TI_preempt_lazy_count, thread_info, preempt_lazy_count); BLANK(); OFFSET(crypto_tfm_ctx_offset, crypto_tfm, __crt_ctx); @@ -71,4 +72,5 @@ BLANK(); DEFINE(PTREGS_SIZE, sizeof(struct pt_regs)); + DEFINE(_PREEMPT_ENABLED, PREEMPT_ENABLED); } diff -Nur linux-3.18.14.orig/arch/x86/kernel/cpu/mcheck/mce.c linux-3.18.14-rt/arch/x86/kernel/cpu/mcheck/mce.c --- linux-3.18.14.orig/arch/x86/kernel/cpu/mcheck/mce.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/x86/kernel/cpu/mcheck/mce.c 2015-05-31 15:32:46.641635383 -0500 @@ -41,6 +41,8 @@ #include #include #include +#include +#include #include #include @@ -1266,7 +1268,7 @@ static unsigned long check_interval = 5 * 60; /* 5 minutes */ static DEFINE_PER_CPU(unsigned long, mce_next_interval); /* in jiffies */ -static DEFINE_PER_CPU(struct timer_list, mce_timer); +static DEFINE_PER_CPU(struct hrtimer, mce_timer); static unsigned long mce_adjust_timer_default(unsigned long interval) { @@ -1283,14 +1285,11 @@ return test_and_clear_bit(0, v); } -static void mce_timer_fn(unsigned long data) +static enum hrtimer_restart mce_timer_fn(struct hrtimer *timer) { - struct timer_list *t = this_cpu_ptr(&mce_timer); unsigned long iv; int notify; - WARN_ON(smp_processor_id() != data); - if (mce_available(this_cpu_ptr(&cpu_info))) { machine_check_poll(MCP_TIMESTAMP, this_cpu_ptr(&mce_poll_banks)); @@ -1313,9 +1312,11 @@ __this_cpu_write(mce_next_interval, iv); /* Might have become 0 after CMCI storm subsided */ if (iv) { - t->expires = jiffies + iv; - add_timer_on(t, smp_processor_id()); + hrtimer_forward_now(timer, ns_to_ktime( + jiffies_to_usecs(iv) * 1000ULL)); + return HRTIMER_RESTART; } + return HRTIMER_NORESTART; } /* @@ -1323,28 +1324,37 @@ */ void mce_timer_kick(unsigned long interval) { - struct timer_list *t = this_cpu_ptr(&mce_timer); - unsigned long when = jiffies + interval; + struct hrtimer *t = this_cpu_ptr(&mce_timer); unsigned long iv = __this_cpu_read(mce_next_interval); - if (timer_pending(t)) { - if (time_before(when, t->expires)) - mod_timer_pinned(t, when); + if (hrtimer_active(t)) { + s64 exp; + s64 intv_us; + + intv_us = jiffies_to_usecs(interval); + exp = ktime_to_us(hrtimer_expires_remaining(t)); + if (intv_us < exp) { + hrtimer_cancel(t); + hrtimer_start_range_ns(t, + ns_to_ktime(intv_us * 1000), + 0, HRTIMER_MODE_REL_PINNED); + } } else { - t->expires = round_jiffies(when); - add_timer_on(t, smp_processor_id()); + hrtimer_start_range_ns(t, + ns_to_ktime(jiffies_to_usecs(interval) * 1000ULL), + 0, HRTIMER_MODE_REL_PINNED); } if (interval < iv) __this_cpu_write(mce_next_interval, interval); } -/* Must not be called in IRQ context where del_timer_sync() can deadlock */ +/* Must not be called in IRQ context where hrtimer_cancel() can deadlock */ static void mce_timer_delete_all(void) { int cpu; for_each_online_cpu(cpu) - del_timer_sync(&per_cpu(mce_timer, cpu)); + hrtimer_cancel(&per_cpu(mce_timer, cpu)); } static void mce_do_trigger(struct work_struct *work) @@ -1354,6 +1364,56 @@ static DECLARE_WORK(mce_trigger_work, mce_do_trigger); +static void __mce_notify_work(struct swork_event *event) +{ + /* Not more than two messages every minute */ + static DEFINE_RATELIMIT_STATE(ratelimit, 60*HZ, 2); + + /* wake processes polling /dev/mcelog */ + wake_up_interruptible(&mce_chrdev_wait); + + /* + * There is no risk of missing notifications because + * work_pending is always cleared before the function is + * executed. + */ + if (mce_helper[0] && !work_pending(&mce_trigger_work)) + schedule_work(&mce_trigger_work); + + if (__ratelimit(&ratelimit)) + pr_info(HW_ERR "Machine check events logged\n"); +} + +#ifdef CONFIG_PREEMPT_RT_FULL +static bool notify_work_ready __read_mostly; +static struct swork_event notify_work; + +static int mce_notify_work_init(void) +{ + int err; + + err = swork_get(); + if (err) + return err; + + INIT_SWORK(¬ify_work, __mce_notify_work); + notify_work_ready = true; + return 0; +} + +static void mce_notify_work(void) +{ + if (notify_work_ready) + swork_queue(¬ify_work); +} +#else +static void mce_notify_work(void) +{ + __mce_notify_work(NULL); +} +static inline int mce_notify_work_init(void) { return 0; } +#endif + /* * Notify the user(s) about new machine check events. * Can be called from interrupt context, but not from machine check/NMI @@ -1361,19 +1421,8 @@ */ int mce_notify_irq(void) { - /* Not more than two messages every minute */ - static DEFINE_RATELIMIT_STATE(ratelimit, 60*HZ, 2); - if (test_and_clear_bit(0, &mce_need_notify)) { - /* wake processes polling /dev/mcelog */ - wake_up_interruptible(&mce_chrdev_wait); - - if (mce_helper[0]) - schedule_work(&mce_trigger_work); - - if (__ratelimit(&ratelimit)) - pr_info(HW_ERR "Machine check events logged\n"); - + mce_notify_work(); return 1; } return 0; @@ -1644,7 +1693,7 @@ } } -static void mce_start_timer(unsigned int cpu, struct timer_list *t) +static void mce_start_timer(unsigned int cpu, struct hrtimer *t) { unsigned long iv = check_interval * HZ; @@ -1653,16 +1702,17 @@ per_cpu(mce_next_interval, cpu) = iv; - t->expires = round_jiffies(jiffies + iv); - add_timer_on(t, cpu); + hrtimer_start_range_ns(t, ns_to_ktime(jiffies_to_usecs(iv) * 1000ULL), + 0, HRTIMER_MODE_REL_PINNED); } static void __mcheck_cpu_init_timer(void) { - struct timer_list *t = this_cpu_ptr(&mce_timer); + struct hrtimer *t = this_cpu_ptr(&mce_timer); unsigned int cpu = smp_processor_id(); - setup_timer(t, mce_timer_fn, cpu); + hrtimer_init(t, CLOCK_MONOTONIC, HRTIMER_MODE_REL); + t->function = mce_timer_fn; mce_start_timer(cpu, t); } @@ -2339,6 +2389,8 @@ if (!mce_available(raw_cpu_ptr(&cpu_info))) return; + hrtimer_cancel(this_cpu_ptr(&mce_timer)); + if (!(action & CPU_TASKS_FROZEN)) cmci_clear(); for (i = 0; i < mca_cfg.banks; i++) { @@ -2365,6 +2417,7 @@ if (b->init) wrmsrl(MSR_IA32_MCx_CTL(i), b->ctl); } + __mcheck_cpu_init_timer(); } /* Get notified when a cpu comes on/off. Be hotplug friendly. */ @@ -2372,7 +2425,6 @@ mce_cpu_callback(struct notifier_block *nfb, unsigned long action, void *hcpu) { unsigned int cpu = (unsigned long)hcpu; - struct timer_list *t = &per_cpu(mce_timer, cpu); switch (action & ~CPU_TASKS_FROZEN) { case CPU_ONLINE: @@ -2392,11 +2444,9 @@ break; case CPU_DOWN_PREPARE: smp_call_function_single(cpu, mce_disable_cpu, &action, 1); - del_timer_sync(t); break; case CPU_DOWN_FAILED: smp_call_function_single(cpu, mce_reenable_cpu, &action, 1); - mce_start_timer(cpu, t); break; } @@ -2435,6 +2485,10 @@ goto err_out; } + err = mce_notify_work_init(); + if (err) + goto err_out; + if (!zalloc_cpumask_var(&mce_device_initialized, GFP_KERNEL)) { err = -ENOMEM; goto err_out; diff -Nur linux-3.18.14.orig/arch/x86/kernel/entry_32.S linux-3.18.14-rt/arch/x86/kernel/entry_32.S --- linux-3.18.14.orig/arch/x86/kernel/entry_32.S 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/x86/kernel/entry_32.S 2015-05-31 15:32:46.641635383 -0500 @@ -359,8 +359,24 @@ ENTRY(resume_kernel) DISABLE_INTERRUPTS(CLBR_ANY) need_resched: + # preempt count == 0 + NEED_RS set? cmpl $0,PER_CPU_VAR(__preempt_count) +#ifndef CONFIG_PREEMPT_LAZY jnz restore_all +#else + jz test_int_off + + # atleast preempt count == 0 ? + cmpl $_PREEMPT_ENABLED,PER_CPU_VAR(__preempt_count) + jne restore_all + + cmpl $0,TI_preempt_lazy_count(%ebp) # non-zero preempt_lazy_count ? + jnz restore_all + + testl $_TIF_NEED_RESCHED_LAZY, TI_flags(%ebp) + jz restore_all +test_int_off: +#endif testl $X86_EFLAGS_IF,PT_EFLAGS(%esp) # interrupts off (exception path) ? jz restore_all call preempt_schedule_irq @@ -591,7 +607,7 @@ ALIGN RING0_PTREGS_FRAME # can't unwind into user space anyway work_pending: - testb $_TIF_NEED_RESCHED, %cl + testl $_TIF_NEED_RESCHED_MASK, %ecx jz work_notifysig work_resched: call schedule @@ -604,7 +620,7 @@ andl $_TIF_WORK_MASK, %ecx # is there any work to be done other # than syscall tracing? jz restore_all - testb $_TIF_NEED_RESCHED, %cl + testl $_TIF_NEED_RESCHED_MASK, %ecx jnz work_resched work_notifysig: # deal with pending signals and diff -Nur linux-3.18.14.orig/arch/x86/kernel/entry_64.S linux-3.18.14-rt/arch/x86/kernel/entry_64.S --- linux-3.18.14.orig/arch/x86/kernel/entry_64.S 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/x86/kernel/entry_64.S 2015-05-31 15:32:46.649635383 -0500 @@ -454,8 +454,8 @@ /* Handle reschedules */ /* edx: work, edi: workmask */ sysret_careful: - bt $TIF_NEED_RESCHED,%edx - jnc sysret_signal + testl $_TIF_NEED_RESCHED_MASK,%edx + jz sysret_signal TRACE_IRQS_ON ENABLE_INTERRUPTS(CLBR_NONE) pushq_cfi %rdi @@ -554,8 +554,8 @@ /* First do a reschedule test. */ /* edx: work, edi: workmask */ int_careful: - bt $TIF_NEED_RESCHED,%edx - jnc int_very_careful + testl $_TIF_NEED_RESCHED_MASK,%edx + jz int_very_careful TRACE_IRQS_ON ENABLE_INTERRUPTS(CLBR_NONE) pushq_cfi %rdi @@ -870,8 +870,8 @@ /* edi: workmask, edx: work */ retint_careful: CFI_RESTORE_STATE - bt $TIF_NEED_RESCHED,%edx - jnc retint_signal + testl $_TIF_NEED_RESCHED_MASK,%edx + jz retint_signal TRACE_IRQS_ON ENABLE_INTERRUPTS(CLBR_NONE) pushq_cfi %rdi @@ -903,7 +903,22 @@ /* rcx: threadinfo. interrupts off. */ ENTRY(retint_kernel) cmpl $0,PER_CPU_VAR(__preempt_count) +#ifndef CONFIG_PREEMPT_LAZY jnz retint_restore_args +#else + jz check_int_off + + # atleast preempt count == 0 ? + cmpl $_PREEMPT_ENABLED,PER_CPU_VAR(__preempt_count) + jnz retint_restore_args + + cmpl $0, TI_preempt_lazy_count(%rcx) + jnz retint_restore_args + + bt $TIF_NEED_RESCHED_LAZY,TI_flags(%rcx) + jnc retint_restore_args +check_int_off: +#endif bt $9,EFLAGS-ARGOFFSET(%rsp) /* interrupts off? */ jnc retint_restore_args call preempt_schedule_irq @@ -1119,6 +1134,7 @@ jmp 2b .previous +#ifndef CONFIG_PREEMPT_RT_FULL /* Call softirq on interrupt stack. Interrupts are off. */ ENTRY(do_softirq_own_stack) CFI_STARTPROC @@ -1138,6 +1154,7 @@ ret CFI_ENDPROC END(do_softirq_own_stack) +#endif #ifdef CONFIG_XEN idtentry xen_hypervisor_callback xen_do_hypervisor_callback has_error_code=0 @@ -1302,7 +1319,7 @@ movq %rsp,%rdi /* &pt_regs */ call sync_regs movq %rax,%rsp /* switch stack for scheduling */ - testl $_TIF_NEED_RESCHED,%ebx + testl $_TIF_NEED_RESCHED_MASK,%ebx jnz paranoid_schedule movl %ebx,%edx /* arg3: thread flags */ TRACE_IRQS_ON diff -Nur linux-3.18.14.orig/arch/x86/kernel/irq_32.c linux-3.18.14-rt/arch/x86/kernel/irq_32.c --- linux-3.18.14.orig/arch/x86/kernel/irq_32.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/x86/kernel/irq_32.c 2015-05-31 15:32:46.653635383 -0500 @@ -142,6 +142,7 @@ cpu, per_cpu(hardirq_stack, cpu), per_cpu(softirq_stack, cpu)); } +#ifndef CONFIG_PREEMPT_RT_FULL void do_softirq_own_stack(void) { struct thread_info *curstk; @@ -160,6 +161,7 @@ call_on_stack(__do_softirq, isp); } +#endif bool handle_irq(unsigned irq, struct pt_regs *regs) { diff -Nur linux-3.18.14.orig/arch/x86/kernel/process_32.c linux-3.18.14-rt/arch/x86/kernel/process_32.c --- linux-3.18.14.orig/arch/x86/kernel/process_32.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/x86/kernel/process_32.c 2015-05-31 15:32:46.653635383 -0500 @@ -35,6 +35,7 @@ #include #include #include +#include #include #include @@ -214,6 +215,35 @@ } EXPORT_SYMBOL_GPL(start_thread); +#ifdef CONFIG_PREEMPT_RT_FULL +static void switch_kmaps(struct task_struct *prev_p, struct task_struct *next_p) +{ + int i; + + /* + * Clear @prev's kmap_atomic mappings + */ + for (i = 0; i < prev_p->kmap_idx; i++) { + int idx = i + KM_TYPE_NR * smp_processor_id(); + pte_t *ptep = kmap_pte - idx; + + kpte_clear_flush(ptep, __fix_to_virt(FIX_KMAP_BEGIN + idx)); + } + /* + * Restore @next_p's kmap_atomic mappings + */ + for (i = 0; i < next_p->kmap_idx; i++) { + int idx = i + KM_TYPE_NR * smp_processor_id(); + + if (!pte_none(next_p->kmap_pte[i])) + set_pte(kmap_pte - idx, next_p->kmap_pte[i]); + } +} +#else +static inline void +switch_kmaps(struct task_struct *prev_p, struct task_struct *next_p) { } +#endif + /* * switch_to(x,y) should switch tasks from x to y. @@ -301,6 +331,8 @@ task_thread_info(next_p)->flags & _TIF_WORK_CTXSW_NEXT)) __switch_to_xtra(prev_p, next_p, tss); + switch_kmaps(prev_p, next_p); + /* * Leave lazy mode, flushing any hypercalls made here. * This must be done before restoring TLS segments so diff -Nur linux-3.18.14.orig/arch/x86/kernel/signal.c linux-3.18.14-rt/arch/x86/kernel/signal.c --- linux-3.18.14.orig/arch/x86/kernel/signal.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/x86/kernel/signal.c 2015-05-31 15:32:46.653635383 -0500 @@ -746,6 +746,14 @@ mce_notify_process(); #endif /* CONFIG_X86_64 && CONFIG_X86_MCE */ +#ifdef ARCH_RT_DELAYS_SIGNAL_SEND + if (unlikely(current->forced_info.si_signo)) { + struct task_struct *t = current; + force_sig_info(t->forced_info.si_signo, &t->forced_info, t); + t->forced_info.si_signo = 0; + } +#endif + if (thread_info_flags & _TIF_UPROBE) uprobe_notify_resume(regs); diff -Nur linux-3.18.14.orig/arch/x86/kernel/traps.c linux-3.18.14-rt/arch/x86/kernel/traps.c --- linux-3.18.14.orig/arch/x86/kernel/traps.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/x86/kernel/traps.c 2015-05-31 15:32:46.657635383 -0500 @@ -87,9 +87,21 @@ local_irq_enable(); } -static inline void preempt_conditional_sti(struct pt_regs *regs) +static inline void conditional_sti_ist(struct pt_regs *regs) { +#ifdef CONFIG_X86_64 + /* + * X86_64 uses a per CPU stack on the IST for certain traps + * like int3. The task can not be preempted when using one + * of these stacks, thus preemption must be disabled, otherwise + * the stack can be corrupted if the task is scheduled out, + * and another task comes in and uses this stack. + * + * On x86_32 the task keeps its own stack and it is OK if the + * task schedules out. + */ preempt_count_inc(); +#endif if (regs->flags & X86_EFLAGS_IF) local_irq_enable(); } @@ -100,11 +112,13 @@ local_irq_disable(); } -static inline void preempt_conditional_cli(struct pt_regs *regs) +static inline void conditional_cli_ist(struct pt_regs *regs) { if (regs->flags & X86_EFLAGS_IF) local_irq_disable(); +#ifdef CONFIG_X86_64 preempt_count_dec(); +#endif } static nokprobe_inline int @@ -372,9 +386,9 @@ * as we may switch to the interrupt stack. */ debug_stack_usage_inc(); - preempt_conditional_sti(regs); + conditional_sti_ist(regs); do_trap(X86_TRAP_BP, SIGTRAP, "int3", regs, error_code, NULL); - preempt_conditional_cli(regs); + conditional_cli_ist(regs); debug_stack_usage_dec(); exit: exception_exit(prev_state); @@ -517,12 +531,12 @@ debug_stack_usage_inc(); /* It's safe to allow irq's after DR6 has been saved */ - preempt_conditional_sti(regs); + conditional_sti_ist(regs); if (regs->flags & X86_VM_MASK) { handle_vm86_trap((struct kernel_vm86_regs *) regs, error_code, X86_TRAP_DB); - preempt_conditional_cli(regs); + conditional_cli_ist(regs); debug_stack_usage_dec(); goto exit; } @@ -542,7 +556,7 @@ si_code = get_si_code(tsk->thread.debugreg6); if (tsk->thread.debugreg6 & (DR_STEP | DR_TRAP_BITS) || user_icebp) send_sigtrap(tsk, regs, error_code, si_code); - preempt_conditional_cli(regs); + conditional_cli_ist(regs); debug_stack_usage_dec(); exit: diff -Nur linux-3.18.14.orig/arch/x86/kvm/lapic.c linux-3.18.14-rt/arch/x86/kvm/lapic.c --- linux-3.18.14.orig/arch/x86/kvm/lapic.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/x86/kvm/lapic.c 2015-05-31 15:32:46.693635383 -0500 @@ -1034,8 +1034,38 @@ apic->divide_count); } + +static enum hrtimer_restart apic_timer_fn(struct hrtimer *data); + +static void apic_timer_expired(struct hrtimer *data) +{ + int ret, i = 0; + enum hrtimer_restart r; + struct kvm_timer *ktimer = container_of(data, struct kvm_timer, timer); + + r = apic_timer_fn(data); + + if (r == HRTIMER_RESTART) { + do { + ret = hrtimer_start_expires(data, HRTIMER_MODE_ABS); + if (ret == -ETIME) + hrtimer_add_expires_ns(&ktimer->timer, + ktimer->period); + i++; + } while (ret == -ETIME && i < 10); + + if (ret == -ETIME) { + printk_once(KERN_ERR "%s: failed to reprogram timer\n", + __func__); + WARN_ON_ONCE(1); + } + } +} + + static void start_apic_timer(struct kvm_lapic *apic) { + int ret; ktime_t now; atomic_set(&apic->lapic_timer.pending, 0); @@ -1065,9 +1095,11 @@ } } - hrtimer_start(&apic->lapic_timer.timer, + ret = hrtimer_start(&apic->lapic_timer.timer, ktime_add_ns(now, apic->lapic_timer.period), HRTIMER_MODE_ABS); + if (ret == -ETIME) + apic_timer_expired(&apic->lapic_timer.timer); apic_debug("%s: bus cycle is %" PRId64 "ns, now 0x%016" PRIx64 ", " @@ -1097,8 +1129,10 @@ ns = (tscdeadline - guest_tsc) * 1000000ULL; do_div(ns, this_tsc_khz); } - hrtimer_start(&apic->lapic_timer.timer, + ret = hrtimer_start(&apic->lapic_timer.timer, ktime_add_ns(now, ns), HRTIMER_MODE_ABS); + if (ret == -ETIME) + apic_timer_expired(&apic->lapic_timer.timer); local_irq_restore(flags); } @@ -1539,7 +1573,7 @@ struct kvm_timer *ktimer = container_of(data, struct kvm_timer, timer); struct kvm_lapic *apic = container_of(ktimer, struct kvm_lapic, lapic_timer); struct kvm_vcpu *vcpu = apic->vcpu; - wait_queue_head_t *q = &vcpu->wq; + struct swait_head *q = &vcpu->wq; /* * There is a race window between reading and incrementing, but we do @@ -1553,8 +1587,8 @@ kvm_make_request(KVM_REQ_PENDING_TIMER, vcpu); } - if (waitqueue_active(q)) - wake_up_interruptible(q); + if (swaitqueue_active(q)) + swait_wake_interruptible(q); if (lapic_is_periodic(apic)) { hrtimer_add_expires_ns(&ktimer->timer, ktimer->period); @@ -1587,6 +1621,7 @@ hrtimer_init(&apic->lapic_timer.timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS); apic->lapic_timer.timer.function = apic_timer_fn; + apic->lapic_timer.timer.irqsafe = 1; /* * APIC is created enabled. This will prevent kvm_lapic_set_base from @@ -1707,7 +1742,8 @@ timer = &vcpu->arch.apic->lapic_timer.timer; if (hrtimer_cancel(timer)) - hrtimer_start_expires(timer, HRTIMER_MODE_ABS); + if (hrtimer_start_expires(timer, HRTIMER_MODE_ABS) == -ETIME) + apic_timer_expired(timer); } /* diff -Nur linux-3.18.14.orig/arch/x86/kvm/x86.c linux-3.18.14-rt/arch/x86/kvm/x86.c --- linux-3.18.14.orig/arch/x86/kvm/x86.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/x86/kvm/x86.c 2015-05-31 15:32:46.697635383 -0500 @@ -5772,6 +5772,13 @@ goto out; } +#ifdef CONFIG_PREEMPT_RT_FULL + if (!boot_cpu_has(X86_FEATURE_CONSTANT_TSC)) { + printk(KERN_ERR "RT requires X86_FEATURE_CONSTANT_TSC\n"); + return -EOPNOTSUPP; + } +#endif + r = kvm_mmu_module_init(); if (r) goto out_free_percpu; diff -Nur linux-3.18.14.orig/arch/x86/mm/fault.c linux-3.18.14-rt/arch/x86/mm/fault.c --- linux-3.18.14.orig/arch/x86/mm/fault.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/x86/mm/fault.c 2015-05-31 15:32:46.729635382 -0500 @@ -1128,7 +1128,7 @@ * If we're in an interrupt, have no user context or are running * in an atomic region then we must not take the fault: */ - if (unlikely(in_atomic() || !mm)) { + if (unlikely(!mm || pagefault_disabled())) { bad_area_nosemaphore(regs, error_code, address); return; } diff -Nur linux-3.18.14.orig/arch/x86/mm/highmem_32.c linux-3.18.14-rt/arch/x86/mm/highmem_32.c --- linux-3.18.14.orig/arch/x86/mm/highmem_32.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/x86/mm/highmem_32.c 2015-05-31 15:32:46.729635382 -0500 @@ -32,6 +32,7 @@ */ void *kmap_atomic_prot(struct page *page, pgprot_t prot) { + pte_t pte = mk_pte(page, prot); unsigned long vaddr; int idx, type; @@ -45,7 +46,10 @@ idx = type + KM_TYPE_NR*smp_processor_id(); vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx); BUG_ON(!pte_none(*(kmap_pte-idx))); - set_pte(kmap_pte-idx, mk_pte(page, prot)); +#ifdef CONFIG_PREEMPT_RT_FULL + current->kmap_pte[type] = pte; +#endif + set_pte(kmap_pte-idx, pte); arch_flush_lazy_mmu_mode(); return (void *)vaddr; @@ -88,6 +92,9 @@ * is a bad idea also, in case the page changes cacheability * attributes or becomes a protected page in a hypervisor. */ +#ifdef CONFIG_PREEMPT_RT_FULL + current->kmap_pte[type] = __pte(0); +#endif kpte_clear_flush(kmap_pte-idx, vaddr); kmap_atomic_idx_pop(); arch_flush_lazy_mmu_mode(); diff -Nur linux-3.18.14.orig/arch/x86/mm/iomap_32.c linux-3.18.14-rt/arch/x86/mm/iomap_32.c --- linux-3.18.14.orig/arch/x86/mm/iomap_32.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/x86/mm/iomap_32.c 2015-05-31 15:32:46.733635383 -0500 @@ -56,6 +56,7 @@ void *kmap_atomic_prot_pfn(unsigned long pfn, pgprot_t prot) { + pte_t pte = pfn_pte(pfn, prot); unsigned long vaddr; int idx, type; @@ -64,7 +65,12 @@ type = kmap_atomic_idx_push(); idx = type + KM_TYPE_NR * smp_processor_id(); vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx); - set_pte(kmap_pte - idx, pfn_pte(pfn, prot)); + WARN_ON(!pte_none(*(kmap_pte - idx))); + +#ifdef CONFIG_PREEMPT_RT_FULL + current->kmap_pte[type] = pte; +#endif + set_pte(kmap_pte - idx, pte); arch_flush_lazy_mmu_mode(); return (void *)vaddr; @@ -110,6 +116,9 @@ * is a bad idea also, in case the page changes cacheability * attributes or becomes a protected page in a hypervisor. */ +#ifdef CONFIG_PREEMPT_RT_FULL + current->kmap_pte[type] = __pte(0); +#endif kpte_clear_flush(kmap_pte-idx, vaddr); kmap_atomic_idx_pop(); } diff -Nur linux-3.18.14.orig/arch/x86/platform/uv/tlb_uv.c linux-3.18.14-rt/arch/x86/platform/uv/tlb_uv.c --- linux-3.18.14.orig/arch/x86/platform/uv/tlb_uv.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/x86/platform/uv/tlb_uv.c 2015-05-31 15:32:46.733635383 -0500 @@ -714,9 +714,9 @@ quiesce_local_uvhub(hmaster); - spin_lock(&hmaster->queue_lock); + raw_spin_lock(&hmaster->queue_lock); reset_with_ipi(&bau_desc->distribution, bcp); - spin_unlock(&hmaster->queue_lock); + raw_spin_unlock(&hmaster->queue_lock); end_uvhub_quiesce(hmaster); @@ -736,9 +736,9 @@ quiesce_local_uvhub(hmaster); - spin_lock(&hmaster->queue_lock); + raw_spin_lock(&hmaster->queue_lock); reset_with_ipi(&bau_desc->distribution, bcp); - spin_unlock(&hmaster->queue_lock); + raw_spin_unlock(&hmaster->queue_lock); end_uvhub_quiesce(hmaster); @@ -759,7 +759,7 @@ cycles_t tm1; hmaster = bcp->uvhub_master; - spin_lock(&hmaster->disable_lock); + raw_spin_lock(&hmaster->disable_lock); if (!bcp->baudisabled) { stat->s_bau_disabled++; tm1 = get_cycles(); @@ -772,7 +772,7 @@ } } } - spin_unlock(&hmaster->disable_lock); + raw_spin_unlock(&hmaster->disable_lock); } static void count_max_concurr(int stat, struct bau_control *bcp, @@ -835,7 +835,7 @@ */ static void uv1_throttle(struct bau_control *hmaster, struct ptc_stats *stat) { - spinlock_t *lock = &hmaster->uvhub_lock; + raw_spinlock_t *lock = &hmaster->uvhub_lock; atomic_t *v; v = &hmaster->active_descriptor_count; @@ -968,7 +968,7 @@ struct bau_control *hmaster; hmaster = bcp->uvhub_master; - spin_lock(&hmaster->disable_lock); + raw_spin_lock(&hmaster->disable_lock); if (bcp->baudisabled && (get_cycles() >= bcp->set_bau_on_time)) { stat->s_bau_reenabled++; for_each_present_cpu(tcpu) { @@ -980,10 +980,10 @@ tbcp->period_giveups = 0; } } - spin_unlock(&hmaster->disable_lock); + raw_spin_unlock(&hmaster->disable_lock); return 0; } - spin_unlock(&hmaster->disable_lock); + raw_spin_unlock(&hmaster->disable_lock); return -1; } @@ -1899,9 +1899,9 @@ bcp->cong_reps = congested_reps; bcp->disabled_period = sec_2_cycles(disabled_period); bcp->giveup_limit = giveup_limit; - spin_lock_init(&bcp->queue_lock); - spin_lock_init(&bcp->uvhub_lock); - spin_lock_init(&bcp->disable_lock); + raw_spin_lock_init(&bcp->queue_lock); + raw_spin_lock_init(&bcp->uvhub_lock); + raw_spin_lock_init(&bcp->disable_lock); } } diff -Nur linux-3.18.14.orig/arch/x86/platform/uv/uv_time.c linux-3.18.14-rt/arch/x86/platform/uv/uv_time.c --- linux-3.18.14.orig/arch/x86/platform/uv/uv_time.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/x86/platform/uv/uv_time.c 2015-05-31 15:32:46.737635383 -0500 @@ -58,7 +58,7 @@ /* There is one of these allocated per node */ struct uv_rtc_timer_head { - spinlock_t lock; + raw_spinlock_t lock; /* next cpu waiting for timer, local node relative: */ int next_cpu; /* number of cpus on this node: */ @@ -178,7 +178,7 @@ uv_rtc_deallocate_timers(); return -ENOMEM; } - spin_lock_init(&head->lock); + raw_spin_lock_init(&head->lock); head->ncpus = uv_blade_nr_possible_cpus(bid); head->next_cpu = -1; blade_info[bid] = head; @@ -232,7 +232,7 @@ unsigned long flags; int next_cpu; - spin_lock_irqsave(&head->lock, flags); + raw_spin_lock_irqsave(&head->lock, flags); next_cpu = head->next_cpu; *t = expires; @@ -244,12 +244,12 @@ if (uv_setup_intr(cpu, expires)) { *t = ULLONG_MAX; uv_rtc_find_next_timer(head, pnode); - spin_unlock_irqrestore(&head->lock, flags); + raw_spin_unlock_irqrestore(&head->lock, flags); return -ETIME; } } - spin_unlock_irqrestore(&head->lock, flags); + raw_spin_unlock_irqrestore(&head->lock, flags); return 0; } @@ -268,7 +268,7 @@ unsigned long flags; int rc = 0; - spin_lock_irqsave(&head->lock, flags); + raw_spin_lock_irqsave(&head->lock, flags); if ((head->next_cpu == bcpu && uv_read_rtc(NULL) >= *t) || force) rc = 1; @@ -280,7 +280,7 @@ uv_rtc_find_next_timer(head, pnode); } - spin_unlock_irqrestore(&head->lock, flags); + raw_spin_unlock_irqrestore(&head->lock, flags); return rc; } @@ -300,13 +300,18 @@ static cycle_t uv_read_rtc(struct clocksource *cs) { unsigned long offset; + cycle_t cycles; + preempt_disable(); if (uv_get_min_hub_revision_id() == 1) offset = 0; else offset = (uv_blade_processor_id() * L1_CACHE_BYTES) % PAGE_SIZE; - return (cycle_t)uv_read_local_mmr(UVH_RTC | offset); + cycles = (cycle_t)uv_read_local_mmr(UVH_RTC | offset); + preempt_enable(); + + return cycles; } /* diff -Nur linux-3.18.14.orig/arch/xtensa/mm/fault.c linux-3.18.14-rt/arch/xtensa/mm/fault.c --- linux-3.18.14.orig/arch/xtensa/mm/fault.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/arch/xtensa/mm/fault.c 2015-05-31 15:32:46.741635382 -0500 @@ -57,7 +57,7 @@ /* If we're in an interrupt or have no user * context, we must not take the fault.. */ - if (in_atomic() || !mm) { + if (!mm || pagefault_disabled()) { bad_page_fault(regs, address, SIGSEGV); return; } diff -Nur linux-3.18.14.orig/block/blk-core.c linux-3.18.14-rt/block/blk-core.c --- linux-3.18.14.orig/block/blk-core.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/block/blk-core.c 2015-05-31 15:32:46.757635382 -0500 @@ -100,6 +100,9 @@ INIT_LIST_HEAD(&rq->queuelist); INIT_LIST_HEAD(&rq->timeout_list); +#if CONFIG_PREEMPT_RT_FULL + INIT_WORK(&rq->work, __blk_mq_complete_request_remote_work); +#endif rq->cpu = -1; rq->q = q; rq->__sector = (sector_t) -1; @@ -194,7 +197,7 @@ **/ void blk_start_queue(struct request_queue *q) { - WARN_ON(!irqs_disabled()); + WARN_ON_NONRT(!irqs_disabled()); queue_flag_clear(QUEUE_FLAG_STOPPED, q); __blk_run_queue(q); @@ -627,7 +630,7 @@ q->bypass_depth = 1; __set_bit(QUEUE_FLAG_BYPASS, &q->queue_flags); - init_waitqueue_head(&q->mq_freeze_wq); + init_swait_head(&q->mq_freeze_wq); if (blkcg_init_queue(q)) goto fail_bdi; @@ -3037,7 +3040,7 @@ blk_run_queue_async(q); else __blk_run_queue(q); - spin_unlock(q->queue_lock); + spin_unlock_irq(q->queue_lock); } static void flush_plug_callbacks(struct blk_plug *plug, bool from_schedule) @@ -3085,7 +3088,6 @@ void blk_flush_plug_list(struct blk_plug *plug, bool from_schedule) { struct request_queue *q; - unsigned long flags; struct request *rq; LIST_HEAD(list); unsigned int depth; @@ -3105,11 +3107,6 @@ q = NULL; depth = 0; - /* - * Save and disable interrupts here, to avoid doing it for every - * queue lock we have to take. - */ - local_irq_save(flags); while (!list_empty(&list)) { rq = list_entry_rq(list.next); list_del_init(&rq->queuelist); @@ -3122,7 +3119,7 @@ queue_unplugged(q, depth, from_schedule); q = rq->q; depth = 0; - spin_lock(q->queue_lock); + spin_lock_irq(q->queue_lock); } /* @@ -3149,8 +3146,6 @@ */ if (q) queue_unplugged(q, depth, from_schedule); - - local_irq_restore(flags); } void blk_finish_plug(struct blk_plug *plug) diff -Nur linux-3.18.14.orig/block/blk-ioc.c linux-3.18.14-rt/block/blk-ioc.c --- linux-3.18.14.orig/block/blk-ioc.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/block/blk-ioc.c 2015-05-31 15:32:46.761635382 -0500 @@ -7,6 +7,7 @@ #include #include #include +#include #include "blk.h" @@ -109,7 +110,7 @@ spin_unlock(q->queue_lock); } else { spin_unlock_irqrestore(&ioc->lock, flags); - cpu_relax(); + cpu_chill(); spin_lock_irqsave_nested(&ioc->lock, flags, 1); } } @@ -187,7 +188,7 @@ spin_unlock(icq->q->queue_lock); } else { spin_unlock_irqrestore(&ioc->lock, flags); - cpu_relax(); + cpu_chill(); goto retry; } } diff -Nur linux-3.18.14.orig/block/blk-iopoll.c linux-3.18.14-rt/block/blk-iopoll.c --- linux-3.18.14.orig/block/blk-iopoll.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/block/blk-iopoll.c 2015-05-31 15:32:46.761635382 -0500 @@ -35,6 +35,7 @@ list_add_tail(&iop->list, this_cpu_ptr(&blk_cpu_iopoll)); __raise_softirq_irqoff(BLOCK_IOPOLL_SOFTIRQ); local_irq_restore(flags); + preempt_check_resched_rt(); } EXPORT_SYMBOL(blk_iopoll_sched); @@ -132,6 +133,7 @@ __raise_softirq_irqoff(BLOCK_IOPOLL_SOFTIRQ); local_irq_enable(); + preempt_check_resched_rt(); } /** @@ -201,6 +203,7 @@ this_cpu_ptr(&blk_cpu_iopoll)); __raise_softirq_irqoff(BLOCK_IOPOLL_SOFTIRQ); local_irq_enable(); + preempt_check_resched_rt(); } return NOTIFY_OK; diff -Nur linux-3.18.14.orig/block/blk-mq.c linux-3.18.14-rt/block/blk-mq.c --- linux-3.18.14.orig/block/blk-mq.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/block/blk-mq.c 2015-05-31 15:32:46.789635382 -0500 @@ -85,7 +85,7 @@ if (percpu_ref_tryget_live(&q->mq_usage_counter)) return 0; - ret = wait_event_interruptible(q->mq_freeze_wq, + ret = swait_event_interruptible(q->mq_freeze_wq, !q->mq_freeze_depth || blk_queue_dying(q)); if (blk_queue_dying(q)) return -ENODEV; @@ -104,7 +104,7 @@ struct request_queue *q = container_of(ref, struct request_queue, mq_usage_counter); - wake_up_all(&q->mq_freeze_wq); + swait_wake_all(&q->mq_freeze_wq); } static void blk_mq_freeze_queue_start(struct request_queue *q) @@ -123,7 +123,7 @@ static void blk_mq_freeze_queue_wait(struct request_queue *q) { - wait_event(q->mq_freeze_wq, percpu_ref_is_zero(&q->mq_usage_counter)); + swait_event(q->mq_freeze_wq, percpu_ref_is_zero(&q->mq_usage_counter)); } /* @@ -146,7 +146,7 @@ spin_unlock_irq(q->queue_lock); if (wake) { percpu_ref_reinit(&q->mq_usage_counter); - wake_up_all(&q->mq_freeze_wq); + swait_wake_all(&q->mq_freeze_wq); } } @@ -194,6 +194,9 @@ rq->resid_len = 0; rq->sense = NULL; +#ifdef CONFIG_PREEMPT_RT_FULL + INIT_WORK(&rq->work, __blk_mq_complete_request_remote_work); +#endif INIT_LIST_HEAD(&rq->timeout_list); rq->timeout = 0; @@ -313,6 +316,17 @@ } EXPORT_SYMBOL(blk_mq_end_request); +#ifdef CONFIG_PREEMPT_RT_FULL + +void __blk_mq_complete_request_remote_work(struct work_struct *work) +{ + struct request *rq = container_of(work, struct request, work); + + rq->q->softirq_done_fn(rq); +} + +#else + static void __blk_mq_complete_request_remote(void *data) { struct request *rq = data; @@ -320,6 +334,8 @@ rq->q->softirq_done_fn(rq); } +#endif + static void blk_mq_ipi_complete_request(struct request *rq) { struct blk_mq_ctx *ctx = rq->mq_ctx; @@ -331,19 +347,23 @@ return; } - cpu = get_cpu(); + cpu = get_cpu_light(); if (!test_bit(QUEUE_FLAG_SAME_FORCE, &rq->q->queue_flags)) shared = cpus_share_cache(cpu, ctx->cpu); if (cpu != ctx->cpu && !shared && cpu_online(ctx->cpu)) { +#ifdef CONFIG_PREEMPT_RT_FULL + schedule_work_on(ctx->cpu, &rq->work); +#else rq->csd.func = __blk_mq_complete_request_remote; rq->csd.info = rq; rq->csd.flags = 0; smp_call_function_single_async(ctx->cpu, &rq->csd); +#endif } else { rq->q->softirq_done_fn(rq); } - put_cpu(); + put_cpu_light(); } void __blk_mq_complete_request(struct request *rq) @@ -814,9 +834,9 @@ test_bit(BLK_MQ_S_STOPPED, &hctx->state)) continue; - preempt_disable(); + migrate_disable(); blk_mq_run_hw_queue(hctx, async); - preempt_enable(); + migrate_enable(); } } EXPORT_SYMBOL(blk_mq_run_queues); @@ -843,9 +863,9 @@ { clear_bit(BLK_MQ_S_STOPPED, &hctx->state); - preempt_disable(); + migrate_disable(); blk_mq_run_hw_queue(hctx, false); - preempt_enable(); + migrate_enable(); } EXPORT_SYMBOL(blk_mq_start_hw_queue); @@ -870,9 +890,9 @@ continue; clear_bit(BLK_MQ_S_STOPPED, &hctx->state); - preempt_disable(); + migrate_disable(); blk_mq_run_hw_queue(hctx, async); - preempt_enable(); + migrate_enable(); } } EXPORT_SYMBOL(blk_mq_start_stopped_hw_queues); @@ -1494,7 +1514,7 @@ { struct blk_mq_hw_ctx *hctx = data; - if (action == CPU_DEAD || action == CPU_DEAD_FROZEN) + if (action == CPU_POST_DEAD) return blk_mq_hctx_cpu_offline(hctx, cpu); else if (action == CPU_ONLINE || action == CPU_ONLINE_FROZEN) return blk_mq_hctx_cpu_online(hctx, cpu); diff -Nur linux-3.18.14.orig/block/blk-mq-cpu.c linux-3.18.14-rt/block/blk-mq-cpu.c --- linux-3.18.14.orig/block/blk-mq-cpu.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/block/blk-mq-cpu.c 2015-05-31 15:32:46.773635382 -0500 @@ -16,7 +16,7 @@ #include "blk-mq.h" static LIST_HEAD(blk_mq_cpu_notify_list); -static DEFINE_RAW_SPINLOCK(blk_mq_cpu_notify_lock); +static DEFINE_SPINLOCK(blk_mq_cpu_notify_lock); static int blk_mq_main_cpu_notify(struct notifier_block *self, unsigned long action, void *hcpu) @@ -25,7 +25,10 @@ struct blk_mq_cpu_notifier *notify; int ret = NOTIFY_OK; - raw_spin_lock(&blk_mq_cpu_notify_lock); + if (action != CPU_POST_DEAD) + return NOTIFY_OK; + + spin_lock(&blk_mq_cpu_notify_lock); list_for_each_entry(notify, &blk_mq_cpu_notify_list, list) { ret = notify->notify(notify->data, action, cpu); @@ -33,7 +36,7 @@ break; } - raw_spin_unlock(&blk_mq_cpu_notify_lock); + spin_unlock(&blk_mq_cpu_notify_lock); return ret; } @@ -41,16 +44,16 @@ { BUG_ON(!notifier->notify); - raw_spin_lock(&blk_mq_cpu_notify_lock); + spin_lock(&blk_mq_cpu_notify_lock); list_add_tail(¬ifier->list, &blk_mq_cpu_notify_list); - raw_spin_unlock(&blk_mq_cpu_notify_lock); + spin_unlock(&blk_mq_cpu_notify_lock); } void blk_mq_unregister_cpu_notifier(struct blk_mq_cpu_notifier *notifier) { - raw_spin_lock(&blk_mq_cpu_notify_lock); + spin_lock(&blk_mq_cpu_notify_lock); list_del(¬ifier->list); - raw_spin_unlock(&blk_mq_cpu_notify_lock); + spin_unlock(&blk_mq_cpu_notify_lock); } void blk_mq_init_cpu_notifier(struct blk_mq_cpu_notifier *notifier, diff -Nur linux-3.18.14.orig/block/blk-mq.h linux-3.18.14-rt/block/blk-mq.h --- linux-3.18.14.orig/block/blk-mq.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/block/blk-mq.h 2015-05-31 15:32:46.789635382 -0500 @@ -73,7 +73,10 @@ static inline struct blk_mq_ctx *__blk_mq_get_ctx(struct request_queue *q, unsigned int cpu) { - return per_cpu_ptr(q->queue_ctx, cpu); + struct blk_mq_ctx *ctx; + + ctx = per_cpu_ptr(q->queue_ctx, cpu); + return ctx; } /* @@ -84,12 +87,12 @@ */ static inline struct blk_mq_ctx *blk_mq_get_ctx(struct request_queue *q) { - return __blk_mq_get_ctx(q, get_cpu()); + return __blk_mq_get_ctx(q, get_cpu_light()); } static inline void blk_mq_put_ctx(struct blk_mq_ctx *ctx) { - put_cpu(); + put_cpu_light(); } struct blk_mq_alloc_data { diff -Nur linux-3.18.14.orig/block/blk-softirq.c linux-3.18.14-rt/block/blk-softirq.c --- linux-3.18.14.orig/block/blk-softirq.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/block/blk-softirq.c 2015-05-31 15:32:46.789635382 -0500 @@ -51,6 +51,7 @@ raise_softirq_irqoff(BLOCK_SOFTIRQ); local_irq_restore(flags); + preempt_check_resched_rt(); } /* @@ -93,6 +94,7 @@ this_cpu_ptr(&blk_cpu_done)); raise_softirq_irqoff(BLOCK_SOFTIRQ); local_irq_enable(); + preempt_check_resched_rt(); } return NOTIFY_OK; @@ -150,6 +152,7 @@ goto do_local; local_irq_restore(flags); + preempt_check_resched_rt(); } /** diff -Nur linux-3.18.14.orig/block/bounce.c linux-3.18.14-rt/block/bounce.c --- linux-3.18.14.orig/block/bounce.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/block/bounce.c 2015-05-31 15:32:46.793635382 -0500 @@ -54,11 +54,11 @@ unsigned long flags; unsigned char *vto; - local_irq_save(flags); + local_irq_save_nort(flags); vto = kmap_atomic(to->bv_page); memcpy(vto + to->bv_offset, vfrom, to->bv_len); kunmap_atomic(vto); - local_irq_restore(flags); + local_irq_restore_nort(flags); } #else /* CONFIG_HIGHMEM */ diff -Nur linux-3.18.14.orig/crypto/algapi.c linux-3.18.14-rt/crypto/algapi.c --- linux-3.18.14.orig/crypto/algapi.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/crypto/algapi.c 2015-05-31 15:32:46.809635382 -0500 @@ -698,13 +698,13 @@ int crypto_register_notifier(struct notifier_block *nb) { - return blocking_notifier_chain_register(&crypto_chain, nb); + return srcu_notifier_chain_register(&crypto_chain, nb); } EXPORT_SYMBOL_GPL(crypto_register_notifier); int crypto_unregister_notifier(struct notifier_block *nb) { - return blocking_notifier_chain_unregister(&crypto_chain, nb); + return srcu_notifier_chain_unregister(&crypto_chain, nb); } EXPORT_SYMBOL_GPL(crypto_unregister_notifier); diff -Nur linux-3.18.14.orig/crypto/api.c linux-3.18.14-rt/crypto/api.c --- linux-3.18.14.orig/crypto/api.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/crypto/api.c 2015-05-31 15:32:46.861635382 -0500 @@ -31,7 +31,7 @@ DECLARE_RWSEM(crypto_alg_sem); EXPORT_SYMBOL_GPL(crypto_alg_sem); -BLOCKING_NOTIFIER_HEAD(crypto_chain); +SRCU_NOTIFIER_HEAD(crypto_chain); EXPORT_SYMBOL_GPL(crypto_chain); static struct crypto_alg *crypto_larval_wait(struct crypto_alg *alg); @@ -236,10 +236,10 @@ { int ok; - ok = blocking_notifier_call_chain(&crypto_chain, val, v); + ok = srcu_notifier_call_chain(&crypto_chain, val, v); if (ok == NOTIFY_DONE) { request_module("cryptomgr"); - ok = blocking_notifier_call_chain(&crypto_chain, val, v); + ok = srcu_notifier_call_chain(&crypto_chain, val, v); } return ok; diff -Nur linux-3.18.14.orig/crypto/internal.h linux-3.18.14-rt/crypto/internal.h --- linux-3.18.14.orig/crypto/internal.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/crypto/internal.h 2015-05-31 15:32:46.865635381 -0500 @@ -48,7 +48,7 @@ extern struct list_head crypto_alg_list; extern struct rw_semaphore crypto_alg_sem; -extern struct blocking_notifier_head crypto_chain; +extern struct srcu_notifier_head crypto_chain; #ifdef CONFIG_PROC_FS void __init crypto_init_proc(void); @@ -142,7 +142,7 @@ static inline void crypto_notify(unsigned long val, void *v) { - blocking_notifier_call_chain(&crypto_chain, val, v); + srcu_notifier_call_chain(&crypto_chain, val, v); } #endif /* _CRYPTO_INTERNAL_H */ diff -Nur linux-3.18.14.orig/Documentation/hwlat_detector.txt linux-3.18.14-rt/Documentation/hwlat_detector.txt --- linux-3.18.14.orig/Documentation/hwlat_detector.txt 1969-12-31 18:00:00.000000000 -0600 +++ linux-3.18.14-rt/Documentation/hwlat_detector.txt 2015-05-31 15:32:45.457635394 -0500 @@ -0,0 +1,64 @@ +Introduction: +------------- + +The module hwlat_detector is a special purpose kernel module that is used to +detect large system latencies induced by the behavior of certain underlying +hardware or firmware, independent of Linux itself. The code was developed +originally to detect SMIs (System Management Interrupts) on x86 systems, +however there is nothing x86 specific about this patchset. It was +originally written for use by the "RT" patch since the Real Time +kernel is highly latency sensitive. + +SMIs are usually not serviced by the Linux kernel, which typically does not +even know that they are occuring. SMIs are instead are set up by BIOS code +and are serviced by BIOS code, usually for "critical" events such as +management of thermal sensors and fans. Sometimes though, SMIs are used for +other tasks and those tasks can spend an inordinate amount of time in the +handler (sometimes measured in milliseconds). Obviously this is a problem if +you are trying to keep event service latencies down in the microsecond range. + +The hardware latency detector works by hogging all of the cpus for configurable +amounts of time (by calling stop_machine()), polling the CPU Time Stamp Counter +for some period, then looking for gaps in the TSC data. Any gap indicates a +time when the polling was interrupted and since the machine is stopped and +interrupts turned off the only thing that could do that would be an SMI. + +Note that the SMI detector should *NEVER* be used in a production environment. +It is intended to be run manually to determine if the hardware platform has a +problem with long system firmware service routines. + +Usage: +------ + +Loading the module hwlat_detector passing the parameter "enabled=1" (or by +setting the "enable" entry in "hwlat_detector" debugfs toggled on) is the only +step required to start the hwlat_detector. It is possible to redefine the +threshold in microseconds (us) above which latency spikes will be taken +into account (parameter "threshold="). + +Example: + + # modprobe hwlat_detector enabled=1 threshold=100 + +After the module is loaded, it creates a directory named "hwlat_detector" under +the debugfs mountpoint, "/debug/hwlat_detector" for this text. It is necessary +to have debugfs mounted, which might be on /sys/debug on your system. + +The /debug/hwlat_detector interface contains the following files: + +count - number of latency spikes observed since last reset +enable - a global enable/disable toggle (0/1), resets count +max - maximum hardware latency actually observed (usecs) +sample - a pipe from which to read current raw sample data + in the format + (can be opened O_NONBLOCK for a single sample) +threshold - minimum latency value to be considered (usecs) +width - time period to sample with CPUs held (usecs) + must be less than the total window size (enforced) +window - total period of sampling, width being inside (usecs) + +By default we will set width to 500,000 and window to 1,000,000, meaning that +we will sample every 1,000,000 usecs (1s) for 500,000 usecs (0.5s). If we +observe any latencies that exceed the threshold (initially 100 usecs), +then we write to a global sample ring buffer of 8K samples, which is +consumed by reading from the "sample" (pipe) debugfs file interface. diff -Nur linux-3.18.14.orig/Documentation/sysrq.txt linux-3.18.14-rt/Documentation/sysrq.txt --- linux-3.18.14.orig/Documentation/sysrq.txt 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/Documentation/sysrq.txt 2015-05-31 15:32:45.461635394 -0500 @@ -59,10 +59,17 @@ On other - If you know of the key combos for other architectures, please let me know so I can add them to this section. -On all - write a character to /proc/sysrq-trigger. e.g.: - +On all - write a character to /proc/sysrq-trigger, e.g.: echo t > /proc/sysrq-trigger +On all - Enable network SysRq by writing a cookie to icmp_echo_sysrq, e.g. + echo 0x01020304 >/proc/sys/net/ipv4/icmp_echo_sysrq + Send an ICMP echo request with this pattern plus the particular + SysRq command key. Example: + # ping -c1 -s57 -p0102030468 + will trigger the SysRq-H (help) command. + + * What are the 'command' keys? ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 'b' - Will immediately reboot the system without syncing or unmounting diff -Nur linux-3.18.14.orig/Documentation/trace/histograms.txt linux-3.18.14-rt/Documentation/trace/histograms.txt --- linux-3.18.14.orig/Documentation/trace/histograms.txt 1969-12-31 18:00:00.000000000 -0600 +++ linux-3.18.14-rt/Documentation/trace/histograms.txt 2015-05-31 15:32:45.461635394 -0500 @@ -0,0 +1,186 @@ + Using the Linux Kernel Latency Histograms + + +This document gives a short explanation how to enable, configure and use +latency histograms. Latency histograms are primarily relevant in the +context of real-time enabled kernels (CONFIG_PREEMPT/CONFIG_PREEMPT_RT) +and are used in the quality management of the Linux real-time +capabilities. + + +* Purpose of latency histograms + +A latency histogram continuously accumulates the frequencies of latency +data. There are two types of histograms +- potential sources of latencies +- effective latencies + + +* Potential sources of latencies + +Potential sources of latencies are code segments where interrupts, +preemption or both are disabled (aka critical sections). To create +histograms of potential sources of latency, the kernel stores the time +stamp at the start of a critical section, determines the time elapsed +when the end of the section is reached, and increments the frequency +counter of that latency value - irrespective of whether any concurrently +running process is affected by latency or not. +- Configuration items (in the Kernel hacking/Tracers submenu) + CONFIG_INTERRUPT_OFF_LATENCY + CONFIG_PREEMPT_OFF_LATENCY + + +* Effective latencies + +Effective latencies are actually occuring during wakeup of a process. To +determine effective latencies, the kernel stores the time stamp when a +process is scheduled to be woken up, and determines the duration of the +wakeup time shortly before control is passed over to this process. Note +that the apparent latency in user space may be somewhat longer, since the +process may be interrupted after control is passed over to it but before +the execution in user space takes place. Simply measuring the interval +between enqueuing and wakeup may also not appropriate in cases when a +process is scheduled as a result of a timer expiration. The timer may have +missed its deadline, e.g. due to disabled interrupts, but this latency +would not be registered. Therefore, the offsets of missed timers are +recorded in a separate histogram. If both wakeup latency and missed timer +offsets are configured and enabled, a third histogram may be enabled that +records the overall latency as a sum of the timer latency, if any, and the +wakeup latency. This histogram is called "timerandwakeup". +- Configuration items (in the Kernel hacking/Tracers submenu) + CONFIG_WAKEUP_LATENCY + CONFIG_MISSED_TIMER_OFSETS + + +* Usage + +The interface to the administration of the latency histograms is located +in the debugfs file system. To mount it, either enter + +mount -t sysfs nodev /sys +mount -t debugfs nodev /sys/kernel/debug + +from shell command line level, or add + +nodev /sys sysfs defaults 0 0 +nodev /sys/kernel/debug debugfs defaults 0 0 + +to the file /etc/fstab. All latency histogram related files are then +available in the directory /sys/kernel/debug/tracing/latency_hist. A +particular histogram type is enabled by writing non-zero to the related +variable in the /sys/kernel/debug/tracing/latency_hist/enable directory. +Select "preemptirqsoff" for the histograms of potential sources of +latencies and "wakeup" for histograms of effective latencies etc. The +histogram data - one per CPU - are available in the files + +/sys/kernel/debug/tracing/latency_hist/preemptoff/CPUx +/sys/kernel/debug/tracing/latency_hist/irqsoff/CPUx +/sys/kernel/debug/tracing/latency_hist/preemptirqsoff/CPUx +/sys/kernel/debug/tracing/latency_hist/wakeup/CPUx +/sys/kernel/debug/tracing/latency_hist/wakeup/sharedprio/CPUx +/sys/kernel/debug/tracing/latency_hist/missed_timer_offsets/CPUx +/sys/kernel/debug/tracing/latency_hist/timerandwakeup/CPUx + +The histograms are reset by writing non-zero to the file "reset" in a +particular latency directory. To reset all latency data, use + +#!/bin/sh + +TRACINGDIR=/sys/kernel/debug/tracing +HISTDIR=$TRACINGDIR/latency_hist + +if test -d $HISTDIR +then + cd $HISTDIR + for i in `find . | grep /reset$` + do + echo 1 >$i + done +fi + + +* Data format + +Latency data are stored with a resolution of one microsecond. The +maximum latency is 10,240 microseconds. The data are only valid, if the +overflow register is empty. Every output line contains the latency in +microseconds in the first row and the number of samples in the second +row. To display only lines with a positive latency count, use, for +example, + +grep -v " 0$" /sys/kernel/debug/tracing/latency_hist/preemptoff/CPU0 + +#Minimum latency: 0 microseconds. +#Average latency: 0 microseconds. +#Maximum latency: 25 microseconds. +#Total samples: 3104770694 +#There are 0 samples greater or equal than 10240 microseconds +#usecs samples + 0 2984486876 + 1 49843506 + 2 58219047 + 3 5348126 + 4 2187960 + 5 3388262 + 6 959289 + 7 208294 + 8 40420 + 9 4485 + 10 14918 + 11 18340 + 12 25052 + 13 19455 + 14 5602 + 15 969 + 16 47 + 17 18 + 18 14 + 19 1 + 20 3 + 21 2 + 22 5 + 23 2 + 25 1 + + +* Wakeup latency of a selected process + +To only collect wakeup latency data of a particular process, write the +PID of the requested process to + +/sys/kernel/debug/tracing/latency_hist/wakeup/pid + +PIDs are not considered, if this variable is set to 0. + + +* Details of the process with the highest wakeup latency so far + +Selected data of the process that suffered from the highest wakeup +latency that occurred in a particular CPU are available in the file + +/sys/kernel/debug/tracing/latency_hist/wakeup/max_latency-CPUx. + +In addition, other relevant system data at the time when the +latency occurred are given. + +The format of the data is (all in one line): + () \ +<- + +The value of is only relevant in the combined timer +and wakeup latency recording. In the wakeup recording, it is +always 0, in the missed_timer_offsets recording, it is the same +as . + +When retrospectively searching for the origin of a latency and +tracing was not enabled, it may be helpful to know the name and +some basic data of the task that (finally) was switching to the +late real-tlme task. In addition to the victim's data, also the +data of the possible culprit are therefore displayed after the +"<-" symbol. + +Finally, the timestamp of the time when the latency occurred +in . after the most recent system boot +is provided. + +These data are also reset when the wakeup histogram is reset. diff -Nur linux-3.18.14.orig/drivers/acpi/acpica/acglobal.h linux-3.18.14-rt/drivers/acpi/acpica/acglobal.h --- linux-3.18.14.orig/drivers/acpi/acpica/acglobal.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/drivers/acpi/acpica/acglobal.h 2015-05-31 15:32:46.885635381 -0500 @@ -112,7 +112,7 @@ * interrupt level */ ACPI_GLOBAL(acpi_spinlock, acpi_gbl_gpe_lock); /* For GPE data structs and registers */ -ACPI_GLOBAL(acpi_spinlock, acpi_gbl_hardware_lock); /* For ACPI H/W except GPE registers */ +ACPI_GLOBAL(acpi_raw_spinlock, acpi_gbl_hardware_lock); /* For ACPI H/W except GPE registers */ ACPI_GLOBAL(acpi_spinlock, acpi_gbl_reference_count_lock); /* Mutex for _OSI support */ diff -Nur linux-3.18.14.orig/drivers/acpi/acpica/hwregs.c linux-3.18.14-rt/drivers/acpi/acpica/hwregs.c --- linux-3.18.14.orig/drivers/acpi/acpica/hwregs.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/drivers/acpi/acpica/hwregs.c 2015-05-31 15:32:46.929635381 -0500 @@ -269,14 +269,14 @@ ACPI_BITMASK_ALL_FIXED_STATUS, ACPI_FORMAT_UINT64(acpi_gbl_xpm1a_status.address))); - lock_flags = acpi_os_acquire_lock(acpi_gbl_hardware_lock); + raw_spin_lock_irqsave(acpi_gbl_hardware_lock, lock_flags); /* Clear the fixed events in PM1 A/B */ status = acpi_hw_register_write(ACPI_REGISTER_PM1_STATUS, ACPI_BITMASK_ALL_FIXED_STATUS); - acpi_os_release_lock(acpi_gbl_hardware_lock, lock_flags); + raw_spin_unlock_irqrestore(acpi_gbl_hardware_lock, lock_flags); if (ACPI_FAILURE(status)) { goto exit; diff -Nur linux-3.18.14.orig/drivers/acpi/acpica/hwxface.c linux-3.18.14-rt/drivers/acpi/acpica/hwxface.c --- linux-3.18.14.orig/drivers/acpi/acpica/hwxface.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/drivers/acpi/acpica/hwxface.c 2015-05-31 15:32:46.973635380 -0500 @@ -374,7 +374,7 @@ return_ACPI_STATUS(AE_BAD_PARAMETER); } - lock_flags = acpi_os_acquire_lock(acpi_gbl_hardware_lock); + raw_spin_lock_irqsave(acpi_gbl_hardware_lock, lock_flags); /* * At this point, we know that the parent register is one of the @@ -435,7 +435,7 @@ unlock_and_exit: - acpi_os_release_lock(acpi_gbl_hardware_lock, lock_flags); + raw_spin_unlock_irqrestore(acpi_gbl_hardware_lock, lock_flags); return_ACPI_STATUS(status); } diff -Nur linux-3.18.14.orig/drivers/acpi/acpica/utmutex.c linux-3.18.14-rt/drivers/acpi/acpica/utmutex.c --- linux-3.18.14.orig/drivers/acpi/acpica/utmutex.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/drivers/acpi/acpica/utmutex.c 2015-05-31 15:32:46.973635380 -0500 @@ -88,7 +88,7 @@ return_ACPI_STATUS (status); } - status = acpi_os_create_lock (&acpi_gbl_hardware_lock); + status = acpi_os_create_raw_lock (&acpi_gbl_hardware_lock); if (ACPI_FAILURE (status)) { return_ACPI_STATUS (status); } @@ -141,7 +141,7 @@ /* Delete the spinlocks */ acpi_os_delete_lock(acpi_gbl_gpe_lock); - acpi_os_delete_lock(acpi_gbl_hardware_lock); + acpi_os_delete_raw_lock(acpi_gbl_hardware_lock); acpi_os_delete_lock(acpi_gbl_reference_count_lock); /* Delete the reader/writer lock */ diff -Nur linux-3.18.14.orig/drivers/ata/libata-sff.c linux-3.18.14-rt/drivers/ata/libata-sff.c --- linux-3.18.14.orig/drivers/ata/libata-sff.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/drivers/ata/libata-sff.c 2015-05-31 15:32:46.993635380 -0500 @@ -678,9 +678,9 @@ unsigned long flags; unsigned int consumed; - local_irq_save(flags); + local_irq_save_nort(flags); consumed = ata_sff_data_xfer32(dev, buf, buflen, rw); - local_irq_restore(flags); + local_irq_restore_nort(flags); return consumed; } @@ -719,7 +719,7 @@ unsigned long flags; /* FIXME: use a bounce buffer */ - local_irq_save(flags); + local_irq_save_nort(flags); buf = kmap_atomic(page); /* do the actual data transfer */ @@ -727,7 +727,7 @@ do_write); kunmap_atomic(buf); - local_irq_restore(flags); + local_irq_restore_nort(flags); } else { buf = page_address(page); ap->ops->sff_data_xfer(qc->dev, buf + offset, qc->sect_size, @@ -864,7 +864,7 @@ unsigned long flags; /* FIXME: use bounce buffer */ - local_irq_save(flags); + local_irq_save_nort(flags); buf = kmap_atomic(page); /* do the actual data transfer */ @@ -872,7 +872,7 @@ count, rw); kunmap_atomic(buf); - local_irq_restore(flags); + local_irq_restore_nort(flags); } else { buf = page_address(page); consumed = ap->ops->sff_data_xfer(dev, buf + offset, diff -Nur linux-3.18.14.orig/drivers/char/random.c linux-3.18.14-rt/drivers/char/random.c --- linux-3.18.14.orig/drivers/char/random.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/drivers/char/random.c 2015-05-31 15:32:47.013635380 -0500 @@ -776,8 +776,6 @@ } sample; long delta, delta2, delta3; - preempt_disable(); - sample.jiffies = jiffies; sample.cycles = random_get_entropy(); sample.num = num; @@ -818,7 +816,6 @@ */ credit_entropy_bits(r, min_t(int, fls(delta>>1), 11)); } - preempt_enable(); } void add_input_randomness(unsigned int type, unsigned int code, @@ -871,28 +868,27 @@ return *(ptr + f->reg_idx++); } -void add_interrupt_randomness(int irq, int irq_flags) +void add_interrupt_randomness(int irq, int irq_flags, __u64 ip) { struct entropy_store *r; struct fast_pool *fast_pool = this_cpu_ptr(&irq_randomness); - struct pt_regs *regs = get_irq_regs(); unsigned long now = jiffies; cycles_t cycles = random_get_entropy(); __u32 c_high, j_high; - __u64 ip; unsigned long seed; int credit = 0; if (cycles == 0) - cycles = get_reg(fast_pool, regs); + cycles = get_reg(fast_pool, NULL); c_high = (sizeof(cycles) > 4) ? cycles >> 32 : 0; j_high = (sizeof(now) > 4) ? now >> 32 : 0; fast_pool->pool[0] ^= cycles ^ j_high ^ irq; fast_pool->pool[1] ^= now ^ c_high; - ip = regs ? instruction_pointer(regs) : _RET_IP_; + if (!ip) + ip = _RET_IP_; fast_pool->pool[2] ^= ip; fast_pool->pool[3] ^= (sizeof(ip) > 4) ? ip >> 32 : - get_reg(fast_pool, regs); + get_reg(fast_pool, NULL); fast_mix(fast_pool); add_interrupt_bench(cycles); diff -Nur linux-3.18.14.orig/drivers/clocksource/tcb_clksrc.c linux-3.18.14-rt/drivers/clocksource/tcb_clksrc.c --- linux-3.18.14.orig/drivers/clocksource/tcb_clksrc.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/drivers/clocksource/tcb_clksrc.c 2015-05-31 15:32:47.025635380 -0500 @@ -23,8 +23,7 @@ * this 32 bit free-running counter. the second channel is not used. * * - The third channel may be used to provide a 16-bit clockevent - * source, used in either periodic or oneshot mode. This runs - * at 32 KiHZ, and can handle delays of up to two seconds. + * source, used in either periodic or oneshot mode. * * A boot clocksource and clockevent source are also currently needed, * unless the relevant platforms (ARM/AT91, AVR32/AT32) are changed so @@ -74,6 +73,7 @@ struct tc_clkevt_device { struct clock_event_device clkevt; struct clk *clk; + u32 freq; void __iomem *regs; }; @@ -82,13 +82,6 @@ return container_of(clkevt, struct tc_clkevt_device, clkevt); } -/* For now, we always use the 32K clock ... this optimizes for NO_HZ, - * because using one of the divided clocks would usually mean the - * tick rate can never be less than several dozen Hz (vs 0.5 Hz). - * - * A divided clock could be good for high resolution timers, since - * 30.5 usec resolution can seem "low". - */ static u32 timer_clock; static void tc_mode(enum clock_event_mode m, struct clock_event_device *d) @@ -111,11 +104,12 @@ case CLOCK_EVT_MODE_PERIODIC: clk_enable(tcd->clk); - /* slow clock, count up to RC, then irq and restart */ + /* count up to RC, then irq and restart */ __raw_writel(timer_clock | ATMEL_TC_WAVE | ATMEL_TC_WAVESEL_UP_AUTO, regs + ATMEL_TC_REG(2, CMR)); - __raw_writel((32768 + HZ/2) / HZ, tcaddr + ATMEL_TC_REG(2, RC)); + __raw_writel((tcd->freq + HZ / 2) / HZ, + tcaddr + ATMEL_TC_REG(2, RC)); /* Enable clock and interrupts on RC compare */ __raw_writel(ATMEL_TC_CPCS, regs + ATMEL_TC_REG(2, IER)); @@ -128,7 +122,7 @@ case CLOCK_EVT_MODE_ONESHOT: clk_enable(tcd->clk); - /* slow clock, count up to RC, then irq and stop */ + /* count up to RC, then irq and stop */ __raw_writel(timer_clock | ATMEL_TC_CPCSTOP | ATMEL_TC_WAVE | ATMEL_TC_WAVESEL_UP_AUTO, regs + ATMEL_TC_REG(2, CMR)); @@ -157,8 +151,12 @@ .name = "tc_clkevt", .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT, +#ifdef CONFIG_ATMEL_TCB_CLKSRC_USE_SLOW_CLOCK /* Should be lower than at91rm9200's system timer */ .rating = 125, +#else + .rating = 200, +#endif .set_next_event = tc_next_event, .set_mode = tc_mode, }, @@ -178,8 +176,9 @@ return IRQ_NONE; } -static int __init setup_clkevents(struct atmel_tc *tc, int clk32k_divisor_idx) +static int __init setup_clkevents(struct atmel_tc *tc, int divisor_idx) { + unsigned divisor = atmel_tc_divisors[divisor_idx]; int ret; struct clk *t2_clk = tc->clk[2]; int irq = tc->irq[2]; @@ -193,7 +192,11 @@ clkevt.regs = tc->regs; clkevt.clk = t2_clk; - timer_clock = clk32k_divisor_idx; + timer_clock = divisor_idx; + if (!divisor) + clkevt.freq = 32768; + else + clkevt.freq = clk_get_rate(t2_clk) / divisor; clkevt.clkevt.cpumask = cpumask_of(0); @@ -203,7 +206,7 @@ return ret; } - clockevents_config_and_register(&clkevt.clkevt, 32768, 1, 0xffff); + clockevents_config_and_register(&clkevt.clkevt, clkevt.freq, 1, 0xffff); return ret; } @@ -340,7 +343,11 @@ goto err_disable_t1; /* channel 2: periodic and oneshot timer support */ +#ifdef CONFIG_ATMEL_TCB_CLKSRC_USE_SLOW_CLOCK ret = setup_clkevents(tc, clk32k_divisor_idx); +#else + ret = setup_clkevents(tc, best_divisor_idx); +#endif if (ret) goto err_unregister_clksrc; diff -Nur linux-3.18.14.orig/drivers/clocksource/timer-atmel-pit.c linux-3.18.14-rt/drivers/clocksource/timer-atmel-pit.c --- linux-3.18.14.orig/drivers/clocksource/timer-atmel-pit.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/drivers/clocksource/timer-atmel-pit.c 2015-05-31 15:32:47.025635380 -0500 @@ -90,6 +90,7 @@ return elapsed; } +static struct irqaction at91sam926x_pit_irq; /* * Clockevent device: interrupts every 1/HZ (== pit_cycles * MCK/16) */ @@ -100,6 +101,8 @@ switch (mode) { case CLOCK_EVT_MODE_PERIODIC: + /* Set up irq handler */ + setup_irq(at91sam926x_pit_irq.irq, &at91sam926x_pit_irq); /* update clocksource counter */ data->cnt += data->cycle * PIT_PICNT(pit_read(data->base, AT91_PIT_PIVR)); pit_write(data->base, AT91_PIT_MR, @@ -113,6 +116,7 @@ /* disable irq, leaving the clocksource active */ pit_write(data->base, AT91_PIT_MR, (data->cycle - 1) | AT91_PIT_PITEN); + remove_irq(at91sam926x_pit_irq.irq, &at91sam926x_pit_irq); break; case CLOCK_EVT_MODE_RESUME: break; diff -Nur linux-3.18.14.orig/drivers/cpufreq/Kconfig.x86 linux-3.18.14-rt/drivers/cpufreq/Kconfig.x86 --- linux-3.18.14.orig/drivers/cpufreq/Kconfig.x86 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/drivers/cpufreq/Kconfig.x86 2015-05-31 15:32:47.065635380 -0500 @@ -113,7 +113,7 @@ config X86_POWERNOW_K8 tristate "AMD Opteron/Athlon64 PowerNow!" - depends on ACPI && ACPI_PROCESSOR && X86_ACPI_CPUFREQ + depends on ACPI && ACPI_PROCESSOR && X86_ACPI_CPUFREQ && !PREEMPT_RT_BASE help This adds the CPUFreq driver for K8/early Opteron/Athlon64 processors. Support for K10 and newer processors is now in acpi-cpufreq. diff -Nur linux-3.18.14.orig/drivers/gpio/gpio-omap.c linux-3.18.14-rt/drivers/gpio/gpio-omap.c --- linux-3.18.14.orig/drivers/gpio/gpio-omap.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/drivers/gpio/gpio-omap.c 2015-05-31 15:32:47.073635379 -0500 @@ -57,7 +57,7 @@ u32 saved_datain; u32 level_mask; u32 toggle_mask; - spinlock_t lock; + raw_spinlock_t lock; struct gpio_chip chip; struct clk *dbck; u32 mod_usage; @@ -503,19 +503,19 @@ (type & (IRQ_TYPE_LEVEL_LOW|IRQ_TYPE_LEVEL_HIGH))) return -EINVAL; - spin_lock_irqsave(&bank->lock, flags); + raw_spin_lock_irqsave(&bank->lock, flags); offset = GPIO_INDEX(bank, gpio); retval = omap_set_gpio_triggering(bank, offset, type); if (!LINE_USED(bank->mod_usage, offset)) { omap_enable_gpio_module(bank, offset); omap_set_gpio_direction(bank, offset, 1); } else if (!omap_gpio_is_input(bank, BIT(offset))) { - spin_unlock_irqrestore(&bank->lock, flags); + raw_spin_unlock_irqrestore(&bank->lock, flags); return -EINVAL; } bank->irq_usage |= BIT(GPIO_INDEX(bank, gpio)); - spin_unlock_irqrestore(&bank->lock, flags); + raw_spin_unlock_irqrestore(&bank->lock, flags); if (type & (IRQ_TYPE_LEVEL_LOW | IRQ_TYPE_LEVEL_HIGH)) __irq_set_handler_locked(d->irq, handle_level_irq); @@ -633,14 +633,14 @@ return -EINVAL; } - spin_lock_irqsave(&bank->lock, flags); + raw_spin_lock_irqsave(&bank->lock, flags); if (enable) bank->context.wake_en |= gpio_bit; else bank->context.wake_en &= ~gpio_bit; writel_relaxed(bank->context.wake_en, bank->base + bank->regs->wkup_en); - spin_unlock_irqrestore(&bank->lock, flags); + raw_spin_unlock_irqrestore(&bank->lock, flags); return 0; } @@ -675,7 +675,7 @@ if (!BANK_USED(bank)) pm_runtime_get_sync(bank->dev); - spin_lock_irqsave(&bank->lock, flags); + raw_spin_lock_irqsave(&bank->lock, flags); /* Set trigger to none. You need to enable the desired trigger with * request_irq() or set_irq_type(). Only do this if the IRQ line has * not already been requested. @@ -685,7 +685,7 @@ omap_enable_gpio_module(bank, offset); } bank->mod_usage |= BIT(offset); - spin_unlock_irqrestore(&bank->lock, flags); + raw_spin_unlock_irqrestore(&bank->lock, flags); return 0; } @@ -695,11 +695,11 @@ struct gpio_bank *bank = container_of(chip, struct gpio_bank, chip); unsigned long flags; - spin_lock_irqsave(&bank->lock, flags); + raw_spin_lock_irqsave(&bank->lock, flags); bank->mod_usage &= ~(BIT(offset)); omap_disable_gpio_module(bank, offset); omap_reset_gpio(bank, bank->chip.base + offset); - spin_unlock_irqrestore(&bank->lock, flags); + raw_spin_unlock_irqrestore(&bank->lock, flags); /* * If this is the last gpio to be freed in the bank, @@ -799,12 +799,12 @@ unsigned long flags; unsigned offset = GPIO_INDEX(bank, gpio); - spin_lock_irqsave(&bank->lock, flags); + raw_spin_lock_irqsave(&bank->lock, flags); gpio_unlock_as_irq(&bank->chip, offset); bank->irq_usage &= ~(BIT(offset)); omap_disable_gpio_module(bank, offset); omap_reset_gpio(bank, gpio); - spin_unlock_irqrestore(&bank->lock, flags); + raw_spin_unlock_irqrestore(&bank->lock, flags); /* * If this is the last IRQ to be freed in the bank, @@ -828,10 +828,10 @@ unsigned int gpio = omap_irq_to_gpio(bank, d->hwirq); unsigned long flags; - spin_lock_irqsave(&bank->lock, flags); + raw_spin_lock_irqsave(&bank->lock, flags); omap_set_gpio_irqenable(bank, gpio, 0); omap_set_gpio_triggering(bank, GPIO_INDEX(bank, gpio), IRQ_TYPE_NONE); - spin_unlock_irqrestore(&bank->lock, flags); + raw_spin_unlock_irqrestore(&bank->lock, flags); } static void omap_gpio_unmask_irq(struct irq_data *d) @@ -842,7 +842,7 @@ u32 trigger = irqd_get_trigger_type(d); unsigned long flags; - spin_lock_irqsave(&bank->lock, flags); + raw_spin_lock_irqsave(&bank->lock, flags); if (trigger) omap_set_gpio_triggering(bank, GPIO_INDEX(bank, gpio), trigger); @@ -854,7 +854,7 @@ } omap_set_gpio_irqenable(bank, gpio, 1); - spin_unlock_irqrestore(&bank->lock, flags); + raw_spin_unlock_irqrestore(&bank->lock, flags); } /*---------------------------------------------------------------------*/ @@ -867,9 +867,9 @@ OMAP_MPUIO_GPIO_MASKIT / bank->stride; unsigned long flags; - spin_lock_irqsave(&bank->lock, flags); + raw_spin_lock_irqsave(&bank->lock, flags); writel_relaxed(0xffff & ~bank->context.wake_en, mask_reg); - spin_unlock_irqrestore(&bank->lock, flags); + raw_spin_unlock_irqrestore(&bank->lock, flags); return 0; } @@ -882,9 +882,9 @@ OMAP_MPUIO_GPIO_MASKIT / bank->stride; unsigned long flags; - spin_lock_irqsave(&bank->lock, flags); + raw_spin_lock_irqsave(&bank->lock, flags); writel_relaxed(bank->context.wake_en, mask_reg); - spin_unlock_irqrestore(&bank->lock, flags); + raw_spin_unlock_irqrestore(&bank->lock, flags); return 0; } @@ -930,9 +930,9 @@ bank = container_of(chip, struct gpio_bank, chip); reg = bank->base + bank->regs->direction; - spin_lock_irqsave(&bank->lock, flags); + raw_spin_lock_irqsave(&bank->lock, flags); dir = !!(readl_relaxed(reg) & BIT(offset)); - spin_unlock_irqrestore(&bank->lock, flags); + raw_spin_unlock_irqrestore(&bank->lock, flags); return dir; } @@ -942,9 +942,9 @@ unsigned long flags; bank = container_of(chip, struct gpio_bank, chip); - spin_lock_irqsave(&bank->lock, flags); + raw_spin_lock_irqsave(&bank->lock, flags); omap_set_gpio_direction(bank, offset, 1); - spin_unlock_irqrestore(&bank->lock, flags); + raw_spin_unlock_irqrestore(&bank->lock, flags); return 0; } @@ -968,10 +968,10 @@ unsigned long flags; bank = container_of(chip, struct gpio_bank, chip); - spin_lock_irqsave(&bank->lock, flags); + raw_spin_lock_irqsave(&bank->lock, flags); bank->set_dataout(bank, offset, value); omap_set_gpio_direction(bank, offset, 0); - spin_unlock_irqrestore(&bank->lock, flags); + raw_spin_unlock_irqrestore(&bank->lock, flags); return 0; } @@ -983,9 +983,9 @@ bank = container_of(chip, struct gpio_bank, chip); - spin_lock_irqsave(&bank->lock, flags); + raw_spin_lock_irqsave(&bank->lock, flags); omap2_set_gpio_debounce(bank, offset, debounce); - spin_unlock_irqrestore(&bank->lock, flags); + raw_spin_unlock_irqrestore(&bank->lock, flags); return 0; } @@ -996,9 +996,9 @@ unsigned long flags; bank = container_of(chip, struct gpio_bank, chip); - spin_lock_irqsave(&bank->lock, flags); + raw_spin_lock_irqsave(&bank->lock, flags); bank->set_dataout(bank, offset, value); - spin_unlock_irqrestore(&bank->lock, flags); + raw_spin_unlock_irqrestore(&bank->lock, flags); } /*---------------------------------------------------------------------*/ @@ -1223,7 +1223,7 @@ else bank->set_dataout = omap_set_gpio_dataout_mask; - spin_lock_init(&bank->lock); + raw_spin_lock_init(&bank->lock); /* Static mapping, never released */ res = platform_get_resource(pdev, IORESOURCE_MEM, 0); @@ -1270,7 +1270,7 @@ unsigned long flags; u32 wake_low, wake_hi; - spin_lock_irqsave(&bank->lock, flags); + raw_spin_lock_irqsave(&bank->lock, flags); /* * Only edges can generate a wakeup event to the PRCM. @@ -1323,7 +1323,7 @@ bank->get_context_loss_count(bank->dev); omap_gpio_dbck_disable(bank); - spin_unlock_irqrestore(&bank->lock, flags); + raw_spin_unlock_irqrestore(&bank->lock, flags); return 0; } @@ -1338,7 +1338,7 @@ unsigned long flags; int c; - spin_lock_irqsave(&bank->lock, flags); + raw_spin_lock_irqsave(&bank->lock, flags); /* * On the first resume during the probe, the context has not @@ -1374,14 +1374,14 @@ if (c != bank->context_loss_count) { omap_gpio_restore_context(bank); } else { - spin_unlock_irqrestore(&bank->lock, flags); + raw_spin_unlock_irqrestore(&bank->lock, flags); return 0; } } } if (!bank->workaround_enabled) { - spin_unlock_irqrestore(&bank->lock, flags); + raw_spin_unlock_irqrestore(&bank->lock, flags); return 0; } @@ -1436,7 +1436,7 @@ } bank->workaround_enabled = false; - spin_unlock_irqrestore(&bank->lock, flags); + raw_spin_unlock_irqrestore(&bank->lock, flags); return 0; } diff -Nur linux-3.18.14.orig/drivers/gpu/drm/i915/i915_gem.c linux-3.18.14-rt/drivers/gpu/drm/i915/i915_gem.c --- linux-3.18.14.orig/drivers/gpu/drm/i915/i915_gem.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/drivers/gpu/drm/i915/i915_gem.c 2015-05-31 15:32:47.081635379 -0500 @@ -5144,7 +5144,7 @@ if (!mutex_is_locked(mutex)) return false; -#if defined(CONFIG_SMP) && !defined(CONFIG_DEBUG_MUTEXES) +#if defined(CONFIG_SMP) && !defined(CONFIG_DEBUG_MUTEXES) && !defined(CONFIG_PREEMPT_RT_BASE) return mutex->owner == task; #else /* Since UP may be pre-empted, we cannot assume that we own the lock */ diff -Nur linux-3.18.14.orig/drivers/gpu/drm/i915/i915_gem_execbuffer.c linux-3.18.14-rt/drivers/gpu/drm/i915/i915_gem_execbuffer.c --- linux-3.18.14.orig/drivers/gpu/drm/i915/i915_gem_execbuffer.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/drivers/gpu/drm/i915/i915_gem_execbuffer.c 2015-05-31 15:32:47.121635379 -0500 @@ -1170,7 +1170,9 @@ return ret; } +#ifndef CONFIG_PREEMPT_RT_BASE trace_i915_gem_ring_dispatch(ring, intel_ring_get_seqno(ring), flags); +#endif i915_gem_execbuffer_move_to_active(vmas, ring); i915_gem_execbuffer_retire_commands(dev, file, ring, batch_obj); diff -Nur linux-3.18.14.orig/drivers/i2c/busses/i2c-omap.c linux-3.18.14-rt/drivers/i2c/busses/i2c-omap.c --- linux-3.18.14.orig/drivers/i2c/busses/i2c-omap.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/drivers/i2c/busses/i2c-omap.c 2015-05-31 15:32:47.125635379 -0500 @@ -875,15 +875,12 @@ u16 mask; u16 stat; - spin_lock(&dev->lock); - mask = omap_i2c_read_reg(dev, OMAP_I2C_IE_REG); stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG); + mask = omap_i2c_read_reg(dev, OMAP_I2C_IE_REG); if (stat & mask) ret = IRQ_WAKE_THREAD; - spin_unlock(&dev->lock); - return ret; } diff -Nur linux-3.18.14.orig/drivers/ide/alim15x3.c linux-3.18.14-rt/drivers/ide/alim15x3.c --- linux-3.18.14.orig/drivers/ide/alim15x3.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/drivers/ide/alim15x3.c 2015-05-31 15:32:47.137635379 -0500 @@ -234,7 +234,7 @@ isa_dev = pci_get_device(PCI_VENDOR_ID_AL, PCI_DEVICE_ID_AL_M1533, NULL); - local_irq_save(flags); + local_irq_save_nort(flags); if (m5229_revision < 0xC2) { /* @@ -325,7 +325,7 @@ } pci_dev_put(north); pci_dev_put(isa_dev); - local_irq_restore(flags); + local_irq_restore_nort(flags); return 0; } diff -Nur linux-3.18.14.orig/drivers/ide/hpt366.c linux-3.18.14-rt/drivers/ide/hpt366.c --- linux-3.18.14.orig/drivers/ide/hpt366.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/drivers/ide/hpt366.c 2015-05-31 15:32:47.169635379 -0500 @@ -1241,7 +1241,7 @@ dma_old = inb(base + 2); - local_irq_save(flags); + local_irq_save_nort(flags); dma_new = dma_old; pci_read_config_byte(dev, hwif->channel ? 0x4b : 0x43, &masterdma); @@ -1252,7 +1252,7 @@ if (dma_new != dma_old) outb(dma_new, base + 2); - local_irq_restore(flags); + local_irq_restore_nort(flags); printk(KERN_INFO " %s: BM-DMA at 0x%04lx-0x%04lx\n", hwif->name, base, base + 7); diff -Nur linux-3.18.14.orig/drivers/ide/ide-io.c linux-3.18.14-rt/drivers/ide/ide-io.c --- linux-3.18.14.orig/drivers/ide/ide-io.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/drivers/ide/ide-io.c 2015-05-31 15:32:47.169635379 -0500 @@ -659,7 +659,7 @@ /* disable_irq_nosync ?? */ disable_irq(hwif->irq); /* local CPU only, as if we were handling an interrupt */ - local_irq_disable(); + local_irq_disable_nort(); if (hwif->polling) { startstop = handler(drive); } else if (drive_is_ready(drive)) { diff -Nur linux-3.18.14.orig/drivers/ide/ide-iops.c linux-3.18.14-rt/drivers/ide/ide-iops.c --- linux-3.18.14.orig/drivers/ide/ide-iops.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/drivers/ide/ide-iops.c 2015-05-31 15:32:47.185635379 -0500 @@ -129,12 +129,12 @@ if ((stat & ATA_BUSY) == 0) break; - local_irq_restore(flags); + local_irq_restore_nort(flags); *rstat = stat; return -EBUSY; } } - local_irq_restore(flags); + local_irq_restore_nort(flags); } /* * Allow status to settle, then read it again. diff -Nur linux-3.18.14.orig/drivers/ide/ide-io-std.c linux-3.18.14-rt/drivers/ide/ide-io-std.c --- linux-3.18.14.orig/drivers/ide/ide-io-std.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/drivers/ide/ide-io-std.c 2015-05-31 15:32:47.169635379 -0500 @@ -175,7 +175,7 @@ unsigned long uninitialized_var(flags); if ((io_32bit & 2) && !mmio) { - local_irq_save(flags); + local_irq_save_nort(flags); ata_vlb_sync(io_ports->nsect_addr); } @@ -186,7 +186,7 @@ insl(data_addr, buf, words); if ((io_32bit & 2) && !mmio) - local_irq_restore(flags); + local_irq_restore_nort(flags); if (((len + 1) & 3) < 2) return; @@ -219,7 +219,7 @@ unsigned long uninitialized_var(flags); if ((io_32bit & 2) && !mmio) { - local_irq_save(flags); + local_irq_save_nort(flags); ata_vlb_sync(io_ports->nsect_addr); } @@ -230,7 +230,7 @@ outsl(data_addr, buf, words); if ((io_32bit & 2) && !mmio) - local_irq_restore(flags); + local_irq_restore_nort(flags); if (((len + 1) & 3) < 2) return; diff -Nur linux-3.18.14.orig/drivers/ide/ide-probe.c linux-3.18.14-rt/drivers/ide/ide-probe.c --- linux-3.18.14.orig/drivers/ide/ide-probe.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/drivers/ide/ide-probe.c 2015-05-31 15:32:47.185635379 -0500 @@ -196,10 +196,10 @@ int bswap = 1; /* local CPU only; some systems need this */ - local_irq_save(flags); + local_irq_save_nort(flags); /* read 512 bytes of id info */ hwif->tp_ops->input_data(drive, NULL, id, SECTOR_SIZE); - local_irq_restore(flags); + local_irq_restore_nort(flags); drive->dev_flags |= IDE_DFLAG_ID_READ; #ifdef DEBUG diff -Nur linux-3.18.14.orig/drivers/ide/ide-taskfile.c linux-3.18.14-rt/drivers/ide/ide-taskfile.c --- linux-3.18.14.orig/drivers/ide/ide-taskfile.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/drivers/ide/ide-taskfile.c 2015-05-31 15:32:47.185635379 -0500 @@ -250,7 +250,7 @@ page_is_high = PageHighMem(page); if (page_is_high) - local_irq_save(flags); + local_irq_save_nort(flags); buf = kmap_atomic(page) + offset; @@ -271,7 +271,7 @@ kunmap_atomic(buf); if (page_is_high) - local_irq_restore(flags); + local_irq_restore_nort(flags); len -= nr_bytes; } @@ -414,7 +414,7 @@ } if ((drive->dev_flags & IDE_DFLAG_UNMASK) == 0) - local_irq_disable(); + local_irq_disable_nort(); ide_set_handler(drive, &task_pio_intr, WAIT_WORSTCASE); diff -Nur linux-3.18.14.orig/drivers/infiniband/ulp/ipoib/ipoib_multicast.c linux-3.18.14-rt/drivers/infiniband/ulp/ipoib/ipoib_multicast.c --- linux-3.18.14.orig/drivers/infiniband/ulp/ipoib/ipoib_multicast.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/drivers/infiniband/ulp/ipoib/ipoib_multicast.c 2015-05-31 15:32:47.205635378 -0500 @@ -796,7 +796,7 @@ ipoib_mcast_stop_thread(dev, 0); - local_irq_save(flags); + local_irq_save_nort(flags); netif_addr_lock(dev); spin_lock(&priv->lock); @@ -878,7 +878,7 @@ spin_unlock(&priv->lock); netif_addr_unlock(dev); - local_irq_restore(flags); + local_irq_restore_nort(flags); /* We have to cancel outside of the spinlock */ list_for_each_entry_safe(mcast, tmcast, &remove_list, list) { diff -Nur linux-3.18.14.orig/drivers/input/gameport/gameport.c linux-3.18.14-rt/drivers/input/gameport/gameport.c --- linux-3.18.14.orig/drivers/input/gameport/gameport.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/drivers/input/gameport/gameport.c 2015-05-31 15:32:47.225635378 -0500 @@ -124,12 +124,12 @@ tx = 1 << 30; for(i = 0; i < 50; i++) { - local_irq_save(flags); + local_irq_save_nort(flags); GET_TIME(t1); for (t = 0; t < 50; t++) gameport_read(gameport); GET_TIME(t2); GET_TIME(t3); - local_irq_restore(flags); + local_irq_restore_nort(flags); udelay(i * 10); if ((t = DELTA(t2,t1) - DELTA(t3,t2)) < tx) tx = t; } @@ -148,11 +148,11 @@ tx = 1 << 30; for(i = 0; i < 50; i++) { - local_irq_save(flags); + local_irq_save_nort(flags); rdtscl(t1); for (t = 0; t < 50; t++) gameport_read(gameport); rdtscl(t2); - local_irq_restore(flags); + local_irq_restore_nort(flags); udelay(i * 10); if (t2 - t1 < tx) tx = t2 - t1; } diff -Nur linux-3.18.14.orig/drivers/leds/trigger/Kconfig linux-3.18.14-rt/drivers/leds/trigger/Kconfig --- linux-3.18.14.orig/drivers/leds/trigger/Kconfig 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/drivers/leds/trigger/Kconfig 2015-05-31 15:32:47.229635378 -0500 @@ -61,7 +61,7 @@ config LEDS_TRIGGER_CPU bool "LED CPU Trigger" - depends on LEDS_TRIGGERS + depends on LEDS_TRIGGERS && !PREEMPT_RT_BASE help This allows LEDs to be controlled by active CPUs. This shows the active CPUs across an array of LEDs so you can see which diff -Nur linux-3.18.14.orig/drivers/md/bcache/Kconfig linux-3.18.14-rt/drivers/md/bcache/Kconfig --- linux-3.18.14.orig/drivers/md/bcache/Kconfig 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/drivers/md/bcache/Kconfig 2015-05-31 15:32:47.245635378 -0500 @@ -1,6 +1,7 @@ config BCACHE tristate "Block device as cache" + depends on !PREEMPT_RT_FULL ---help--- Allows a block device to be used as cache for other devices; uses a btree for indexing and the layout is optimized for SSDs. diff -Nur linux-3.18.14.orig/drivers/md/dm.c linux-3.18.14-rt/drivers/md/dm.c --- linux-3.18.14.orig/drivers/md/dm.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/drivers/md/dm.c 2015-05-31 15:32:47.261635378 -0500 @@ -1898,14 +1898,14 @@ if (map_request(ti, clone, md)) goto requeued; - BUG_ON(!irqs_disabled()); + BUG_ON_NONRT(!irqs_disabled()); spin_lock(q->queue_lock); } goto out; requeued: - BUG_ON(!irqs_disabled()); + BUG_ON_NONRT(!irqs_disabled()); spin_lock(q->queue_lock); delay_and_out: diff -Nur linux-3.18.14.orig/drivers/md/raid5.c linux-3.18.14-rt/drivers/md/raid5.c --- linux-3.18.14.orig/drivers/md/raid5.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/drivers/md/raid5.c 2015-05-31 15:32:47.265635378 -0500 @@ -1649,8 +1649,9 @@ struct raid5_percpu *percpu; unsigned long cpu; - cpu = get_cpu(); + cpu = get_cpu_light(); percpu = per_cpu_ptr(conf->percpu, cpu); + spin_lock(&percpu->lock); if (test_bit(STRIPE_OP_BIOFILL, &ops_request)) { ops_run_biofill(sh); overlap_clear++; @@ -1702,7 +1703,8 @@ if (test_and_clear_bit(R5_Overlap, &dev->flags)) wake_up(&sh->raid_conf->wait_for_overlap); } - put_cpu(); + spin_unlock(&percpu->lock); + put_cpu_light(); } static int grow_one_stripe(struct r5conf *conf, int hash) @@ -5708,6 +5710,7 @@ __func__, cpu); break; } + spin_lock_init(&per_cpu_ptr(conf->percpu, cpu)->lock); } put_online_cpus(); diff -Nur linux-3.18.14.orig/drivers/md/raid5.h linux-3.18.14-rt/drivers/md/raid5.h --- linux-3.18.14.orig/drivers/md/raid5.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/drivers/md/raid5.h 2015-05-31 15:32:47.293635378 -0500 @@ -457,6 +457,7 @@ int recovery_disabled; /* per cpu variables */ struct raid5_percpu { + spinlock_t lock; /* Protection for -RT */ struct page *spare_page; /* Used when checking P/Q in raid6 */ void *scribble; /* space for constructing buffer * lists and performing address diff -Nur linux-3.18.14.orig/drivers/misc/hwlat_detector.c linux-3.18.14-rt/drivers/misc/hwlat_detector.c --- linux-3.18.14.orig/drivers/misc/hwlat_detector.c 1969-12-31 18:00:00.000000000 -0600 +++ linux-3.18.14-rt/drivers/misc/hwlat_detector.c 2015-05-31 15:32:47.377635377 -0500 @@ -0,0 +1,1240 @@ +/* + * hwlat_detector.c - A simple Hardware Latency detector. + * + * Use this module to detect large system latencies induced by the behavior of + * certain underlying system hardware or firmware, independent of Linux itself. + * The code was developed originally to detect the presence of SMIs on Intel + * and AMD systems, although there is no dependency upon x86 herein. + * + * The classical example usage of this module is in detecting the presence of + * SMIs or System Management Interrupts on Intel and AMD systems. An SMI is a + * somewhat special form of hardware interrupt spawned from earlier CPU debug + * modes in which the (BIOS/EFI/etc.) firmware arranges for the South Bridge + * LPC (or other device) to generate a special interrupt under certain + * circumstances, for example, upon expiration of a special SMI timer device, + * due to certain external thermal readings, on certain I/O address accesses, + * and other situations. An SMI hits a special CPU pin, triggers a special + * SMI mode (complete with special memory map), and the OS is unaware. + * + * Although certain hardware-inducing latencies are necessary (for example, + * a modern system often requires an SMI handler for correct thermal control + * and remote management) they can wreak havoc upon any OS-level performance + * guarantees toward low-latency, especially when the OS is not even made + * aware of the presence of these interrupts. For this reason, we need a + * somewhat brute force mechanism to detect these interrupts. In this case, + * we do it by hogging all of the CPU(s) for configurable timer intervals, + * sampling the built-in CPU timer, looking for discontiguous readings. + * + * WARNING: This implementation necessarily introduces latencies. Therefore, + * you should NEVER use this module in a production environment + * requiring any kind of low-latency performance guarantee(s). + * + * Copyright (C) 2008-2009 Jon Masters, Red Hat, Inc. + * + * Includes useful feedback from Clark Williams + * + * This file is licensed under the terms of the GNU General Public + * License version 2. This program is licensed "as is" without any + * warranty of any kind, whether express or implied. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define BUF_SIZE_DEFAULT 262144UL /* 8K*(sizeof(entry)) */ +#define BUF_FLAGS (RB_FL_OVERWRITE) /* no block on full */ +#define U64STR_SIZE 22 /* 20 digits max */ + +#define VERSION "1.0.0" +#define BANNER "hwlat_detector: " +#define DRVNAME "hwlat_detector" +#define DEFAULT_SAMPLE_WINDOW 1000000 /* 1s */ +#define DEFAULT_SAMPLE_WIDTH 500000 /* 0.5s */ +#define DEFAULT_LAT_THRESHOLD 10 /* 10us */ + +/* Module metadata */ + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Jon Masters "); +MODULE_DESCRIPTION("A simple hardware latency detector"); +MODULE_VERSION(VERSION); + +/* Module parameters */ + +static int debug; +static int enabled; +static int threshold; + +module_param(debug, int, 0); /* enable debug */ +module_param(enabled, int, 0); /* enable detector */ +module_param(threshold, int, 0); /* latency threshold */ + +/* Buffering and sampling */ + +static struct ring_buffer *ring_buffer; /* sample buffer */ +static DEFINE_MUTEX(ring_buffer_mutex); /* lock changes */ +static unsigned long buf_size = BUF_SIZE_DEFAULT; +static struct task_struct *kthread; /* sampling thread */ + +/* DebugFS filesystem entries */ + +static struct dentry *debug_dir; /* debugfs directory */ +static struct dentry *debug_max; /* maximum TSC delta */ +static struct dentry *debug_count; /* total detect count */ +static struct dentry *debug_sample_width; /* sample width us */ +static struct dentry *debug_sample_window; /* sample window us */ +static struct dentry *debug_sample; /* raw samples us */ +static struct dentry *debug_threshold; /* threshold us */ +static struct dentry *debug_enable; /* enable/disable */ + +/* Individual samples and global state */ + +struct sample; /* latency sample */ +struct data; /* Global state */ + +/* Sampling functions */ +static int __buffer_add_sample(struct sample *sample); +static struct sample *buffer_get_sample(struct sample *sample); + +/* Threading and state */ +static int kthread_fn(void *unused); +static int start_kthread(void); +static int stop_kthread(void); +static void __reset_stats(void); +static int init_stats(void); + +/* Debugfs interface */ +static ssize_t simple_data_read(struct file *filp, char __user *ubuf, + size_t cnt, loff_t *ppos, const u64 *entry); +static ssize_t simple_data_write(struct file *filp, const char __user *ubuf, + size_t cnt, loff_t *ppos, u64 *entry); +static int debug_sample_fopen(struct inode *inode, struct file *filp); +static ssize_t debug_sample_fread(struct file *filp, char __user *ubuf, + size_t cnt, loff_t *ppos); +static int debug_sample_release(struct inode *inode, struct file *filp); +static int debug_enable_fopen(struct inode *inode, struct file *filp); +static ssize_t debug_enable_fread(struct file *filp, char __user *ubuf, + size_t cnt, loff_t *ppos); +static ssize_t debug_enable_fwrite(struct file *file, + const char __user *user_buffer, + size_t user_size, loff_t *offset); + +/* Initialization functions */ +static int init_debugfs(void); +static void free_debugfs(void); +static int detector_init(void); +static void detector_exit(void); + +/* Individual latency samples are stored here when detected and packed into + * the ring_buffer circular buffer, where they are overwritten when + * more than buf_size/sizeof(sample) samples are received. */ +struct sample { + u64 seqnum; /* unique sequence */ + u64 duration; /* ktime delta */ + u64 outer_duration; /* ktime delta (outer loop) */ + struct timespec timestamp; /* wall time */ + unsigned long lost; +}; + +/* keep the global state somewhere. */ +static struct data { + + struct mutex lock; /* protect changes */ + + u64 count; /* total since reset */ + u64 max_sample; /* max hardware latency */ + u64 threshold; /* sample threshold level */ + + u64 sample_window; /* total sampling window (on+off) */ + u64 sample_width; /* active sampling portion of window */ + + atomic_t sample_open; /* whether the sample file is open */ + + wait_queue_head_t wq; /* waitqeue for new sample values */ + +} data; + +/** + * __buffer_add_sample - add a new latency sample recording to the ring buffer + * @sample: The new latency sample value + * + * This receives a new latency sample and records it in a global ring buffer. + * No additional locking is used in this case. + */ +static int __buffer_add_sample(struct sample *sample) +{ + return ring_buffer_write(ring_buffer, + sizeof(struct sample), sample); +} + +/** + * buffer_get_sample - remove a hardware latency sample from the ring buffer + * @sample: Pre-allocated storage for the sample + * + * This retrieves a hardware latency sample from the global circular buffer + */ +static struct sample *buffer_get_sample(struct sample *sample) +{ + struct ring_buffer_event *e = NULL; + struct sample *s = NULL; + unsigned int cpu = 0; + + if (!sample) + return NULL; + + mutex_lock(&ring_buffer_mutex); + for_each_online_cpu(cpu) { + e = ring_buffer_consume(ring_buffer, cpu, NULL, &sample->lost); + if (e) + break; + } + + if (e) { + s = ring_buffer_event_data(e); + memcpy(sample, s, sizeof(struct sample)); + } else + sample = NULL; + mutex_unlock(&ring_buffer_mutex); + + return sample; +} + +#ifndef CONFIG_TRACING +#define time_type ktime_t +#define time_get() ktime_get() +#define time_to_us(x) ktime_to_us(x) +#define time_sub(a, b) ktime_sub(a, b) +#define init_time(a, b) (a).tv64 = b +#define time_u64(a) ((a).tv64) +#else +#define time_type u64 +#define time_get() trace_clock_local() +#define time_to_us(x) div_u64(x, 1000) +#define time_sub(a, b) ((a) - (b)) +#define init_time(a, b) (a = b) +#define time_u64(a) a +#endif +/** + * get_sample - sample the CPU TSC and look for likely hardware latencies + * + * Used to repeatedly capture the CPU TSC (or similar), looking for potential + * hardware-induced latency. Called with interrupts disabled and with + * data.lock held. + */ +static int get_sample(void) +{ + time_type start, t1, t2, last_t2; + s64 diff, total = 0; + u64 sample = 0; + u64 outer_sample = 0; + int ret = -1; + + init_time(last_t2, 0); + start = time_get(); /* start timestamp */ + + do { + + t1 = time_get(); /* we'll look for a discontinuity */ + t2 = time_get(); + + if (time_u64(last_t2)) { + /* Check the delta from outer loop (t2 to next t1) */ + diff = time_to_us(time_sub(t1, last_t2)); + /* This shouldn't happen */ + if (diff < 0) { + pr_err(BANNER "time running backwards\n"); + goto out; + } + if (diff > outer_sample) + outer_sample = diff; + } + last_t2 = t2; + + total = time_to_us(time_sub(t2, start)); /* sample width */ + + /* This checks the inner loop (t1 to t2) */ + diff = time_to_us(time_sub(t2, t1)); /* current diff */ + + /* This shouldn't happen */ + if (diff < 0) { + pr_err(BANNER "time running backwards\n"); + goto out; + } + + if (diff > sample) + sample = diff; /* only want highest value */ + + } while (total <= data.sample_width); + + ret = 0; + + /* If we exceed the threshold value, we have found a hardware latency */ + if (sample > data.threshold || outer_sample > data.threshold) { + struct sample s; + + ret = 1; + + data.count++; + s.seqnum = data.count; + s.duration = sample; + s.outer_duration = outer_sample; + s.timestamp = CURRENT_TIME; + __buffer_add_sample(&s); + + /* Keep a running maximum ever recorded hardware latency */ + if (sample > data.max_sample) + data.max_sample = sample; + } + +out: + return ret; +} + +/* + * kthread_fn - The CPU time sampling/hardware latency detection kernel thread + * @unused: A required part of the kthread API. + * + * Used to periodically sample the CPU TSC via a call to get_sample. We + * disable interrupts, which does (intentionally) introduce latency since we + * need to ensure nothing else might be running (and thus pre-empting). + * Obviously this should never be used in production environments. + * + * Currently this runs on which ever CPU it was scheduled on, but most + * real-worald hardware latency situations occur across several CPUs, + * but we might later generalize this if we find there are any actualy + * systems with alternate SMI delivery or other hardware latencies. + */ +static int kthread_fn(void *unused) +{ + int ret; + u64 interval; + + while (!kthread_should_stop()) { + + mutex_lock(&data.lock); + + local_irq_disable(); + ret = get_sample(); + local_irq_enable(); + + if (ret > 0) + wake_up(&data.wq); /* wake up reader(s) */ + + interval = data.sample_window - data.sample_width; + do_div(interval, USEC_PER_MSEC); /* modifies interval value */ + + mutex_unlock(&data.lock); + + if (msleep_interruptible(interval)) + break; + } + + return 0; +} + +/** + * start_kthread - Kick off the hardware latency sampling/detector kthread + * + * This starts a kernel thread that will sit and sample the CPU timestamp + * counter (TSC or similar) and look for potential hardware latencies. + */ +static int start_kthread(void) +{ + kthread = kthread_run(kthread_fn, NULL, + DRVNAME); + if (IS_ERR(kthread)) { + pr_err(BANNER "could not start sampling thread\n"); + enabled = 0; + return -ENOMEM; + } + + return 0; +} + +/** + * stop_kthread - Inform the hardware latency samping/detector kthread to stop + * + * This kicks the running hardware latency sampling/detector kernel thread and + * tells it to stop sampling now. Use this on unload and at system shutdown. + */ +static int stop_kthread(void) +{ + int ret; + + ret = kthread_stop(kthread); + + return ret; +} + +/** + * __reset_stats - Reset statistics for the hardware latency detector + * + * We use data to store various statistics and global state. We call this + * function in order to reset those when "enable" is toggled on or off, and + * also at initialization. Should be called with data.lock held. + */ +static void __reset_stats(void) +{ + data.count = 0; + data.max_sample = 0; + ring_buffer_reset(ring_buffer); /* flush out old sample entries */ +} + +/** + * init_stats - Setup global state statistics for the hardware latency detector + * + * We use data to store various statistics and global state. We also use + * a global ring buffer (ring_buffer) to keep raw samples of detected hardware + * induced system latencies. This function initializes these structures and + * allocates the global ring buffer also. + */ +static int init_stats(void) +{ + int ret = -ENOMEM; + + mutex_init(&data.lock); + init_waitqueue_head(&data.wq); + atomic_set(&data.sample_open, 0); + + ring_buffer = ring_buffer_alloc(buf_size, BUF_FLAGS); + + if (WARN(!ring_buffer, KERN_ERR BANNER + "failed to allocate ring buffer!\n")) + goto out; + + __reset_stats(); + data.threshold = threshold ?: DEFAULT_LAT_THRESHOLD; /* threshold us */ + data.sample_window = DEFAULT_SAMPLE_WINDOW; /* window us */ + data.sample_width = DEFAULT_SAMPLE_WIDTH; /* width us */ + + ret = 0; + +out: + return ret; + +} + +/* + * simple_data_read - Wrapper read function for global state debugfs entries + * @filp: The active open file structure for the debugfs "file" + * @ubuf: The userspace provided buffer to read value into + * @cnt: The maximum number of bytes to read + * @ppos: The current "file" position + * @entry: The entry to read from + * + * This function provides a generic read implementation for the global state + * "data" structure debugfs filesystem entries. It would be nice to use + * simple_attr_read directly, but we need to make sure that the data.lock + * is held during the actual read. + */ +static ssize_t simple_data_read(struct file *filp, char __user *ubuf, + size_t cnt, loff_t *ppos, const u64 *entry) +{ + char buf[U64STR_SIZE]; + u64 val = 0; + int len = 0; + + memset(buf, 0, sizeof(buf)); + + if (!entry) + return -EFAULT; + + mutex_lock(&data.lock); + val = *entry; + mutex_unlock(&data.lock); + + len = snprintf(buf, sizeof(buf), "%llu\n", (unsigned long long)val); + + return simple_read_from_buffer(ubuf, cnt, ppos, buf, len); + +} + +/* + * simple_data_write - Wrapper write function for global state debugfs entries + * @filp: The active open file structure for the debugfs "file" + * @ubuf: The userspace provided buffer to write value from + * @cnt: The maximum number of bytes to write + * @ppos: The current "file" position + * @entry: The entry to write to + * + * This function provides a generic write implementation for the global state + * "data" structure debugfs filesystem entries. It would be nice to use + * simple_attr_write directly, but we need to make sure that the data.lock + * is held during the actual write. + */ +static ssize_t simple_data_write(struct file *filp, const char __user *ubuf, + size_t cnt, loff_t *ppos, u64 *entry) +{ + char buf[U64STR_SIZE]; + int csize = min(cnt, sizeof(buf)); + u64 val = 0; + int err = 0; + + memset(buf, '\0', sizeof(buf)); + if (copy_from_user(buf, ubuf, csize)) + return -EFAULT; + + buf[U64STR_SIZE-1] = '\0'; /* just in case */ + err = kstrtoull(buf, 10, &val); + if (err) + return -EINVAL; + + mutex_lock(&data.lock); + *entry = val; + mutex_unlock(&data.lock); + + return csize; +} + +/** + * debug_count_fopen - Open function for "count" debugfs entry + * @inode: The in-kernel inode representation of the debugfs "file" + * @filp: The active open file structure for the debugfs "file" + * + * This function provides an open implementation for the "count" debugfs + * interface to the hardware latency detector. + */ +static int debug_count_fopen(struct inode *inode, struct file *filp) +{ + return 0; +} + +/** + * debug_count_fread - Read function for "count" debugfs entry + * @filp: The active open file structure for the debugfs "file" + * @ubuf: The userspace provided buffer to read value into + * @cnt: The maximum number of bytes to read + * @ppos: The current "file" position + * + * This function provides a read implementation for the "count" debugfs + * interface to the hardware latency detector. Can be used to read the + * number of latency readings exceeding the configured threshold since + * the detector was last reset (e.g. by writing a zero into "count"). + */ +static ssize_t debug_count_fread(struct file *filp, char __user *ubuf, + size_t cnt, loff_t *ppos) +{ + return simple_data_read(filp, ubuf, cnt, ppos, &data.count); +} + +/** + * debug_count_fwrite - Write function for "count" debugfs entry + * @filp: The active open file structure for the debugfs "file" + * @ubuf: The user buffer that contains the value to write + * @cnt: The maximum number of bytes to write to "file" + * @ppos: The current position in the debugfs "file" + * + * This function provides a write implementation for the "count" debugfs + * interface to the hardware latency detector. Can be used to write a + * desired value, especially to zero the total count. + */ +static ssize_t debug_count_fwrite(struct file *filp, + const char __user *ubuf, + size_t cnt, + loff_t *ppos) +{ + return simple_data_write(filp, ubuf, cnt, ppos, &data.count); +} + +/** + * debug_enable_fopen - Dummy open function for "enable" debugfs interface + * @inode: The in-kernel inode representation of the debugfs "file" + * @filp: The active open file structure for the debugfs "file" + * + * This function provides an open implementation for the "enable" debugfs + * interface to the hardware latency detector. + */ +static int debug_enable_fopen(struct inode *inode, struct file *filp) +{ + return 0; +} + +/** + * debug_enable_fread - Read function for "enable" debugfs interface + * @filp: The active open file structure for the debugfs "file" + * @ubuf: The userspace provided buffer to read value into + * @cnt: The maximum number of bytes to read + * @ppos: The current "file" position + * + * This function provides a read implementation for the "enable" debugfs + * interface to the hardware latency detector. Can be used to determine + * whether the detector is currently enabled ("0\n" or "1\n" returned). + */ +static ssize_t debug_enable_fread(struct file *filp, char __user *ubuf, + size_t cnt, loff_t *ppos) +{ + char buf[4]; + + if ((cnt < sizeof(buf)) || (*ppos)) + return 0; + + buf[0] = enabled ? '1' : '0'; + buf[1] = '\n'; + buf[2] = '\0'; + if (copy_to_user(ubuf, buf, strlen(buf))) + return -EFAULT; + return *ppos = strlen(buf); +} + +/** + * debug_enable_fwrite - Write function for "enable" debugfs interface + * @filp: The active open file structure for the debugfs "file" + * @ubuf: The user buffer that contains the value to write + * @cnt: The maximum number of bytes to write to "file" + * @ppos: The current position in the debugfs "file" + * + * This function provides a write implementation for the "enable" debugfs + * interface to the hardware latency detector. Can be used to enable or + * disable the detector, which will have the side-effect of possibly + * also resetting the global stats and kicking off the measuring + * kthread (on an enable) or the converse (upon a disable). + */ +static ssize_t debug_enable_fwrite(struct file *filp, + const char __user *ubuf, + size_t cnt, + loff_t *ppos) +{ + char buf[4]; + int csize = min(cnt, sizeof(buf)); + long val = 0; + int err = 0; + + memset(buf, '\0', sizeof(buf)); + if (copy_from_user(buf, ubuf, csize)) + return -EFAULT; + + buf[sizeof(buf)-1] = '\0'; /* just in case */ + err = kstrtoul(buf, 10, &val); + if (0 != err) + return -EINVAL; + + if (val) { + if (enabled) + goto unlock; + enabled = 1; + __reset_stats(); + if (start_kthread()) + return -EFAULT; + } else { + if (!enabled) + goto unlock; + enabled = 0; + err = stop_kthread(); + if (err) { + pr_err(BANNER "cannot stop kthread\n"); + return -EFAULT; + } + wake_up(&data.wq); /* reader(s) should return */ + } +unlock: + return csize; +} + +/** + * debug_max_fopen - Open function for "max" debugfs entry + * @inode: The in-kernel inode representation of the debugfs "file" + * @filp: The active open file structure for the debugfs "file" + * + * This function provides an open implementation for the "max" debugfs + * interface to the hardware latency detector. + */ +static int debug_max_fopen(struct inode *inode, struct file *filp) +{ + return 0; +} + +/** + * debug_max_fread - Read function for "max" debugfs entry + * @filp: The active open file structure for the debugfs "file" + * @ubuf: The userspace provided buffer to read value into + * @cnt: The maximum number of bytes to read + * @ppos: The current "file" position + * + * This function provides a read implementation for the "max" debugfs + * interface to the hardware latency detector. Can be used to determine + * the maximum latency value observed since it was last reset. + */ +static ssize_t debug_max_fread(struct file *filp, char __user *ubuf, + size_t cnt, loff_t *ppos) +{ + return simple_data_read(filp, ubuf, cnt, ppos, &data.max_sample); +} + +/** + * debug_max_fwrite - Write function for "max" debugfs entry + * @filp: The active open file structure for the debugfs "file" + * @ubuf: The user buffer that contains the value to write + * @cnt: The maximum number of bytes to write to "file" + * @ppos: The current position in the debugfs "file" + * + * This function provides a write implementation for the "max" debugfs + * interface to the hardware latency detector. Can be used to reset the + * maximum or set it to some other desired value - if, then, subsequent + * measurements exceed this value, the maximum will be updated. + */ +static ssize_t debug_max_fwrite(struct file *filp, + const char __user *ubuf, + size_t cnt, + loff_t *ppos) +{ + return simple_data_write(filp, ubuf, cnt, ppos, &data.max_sample); +} + + +/** + * debug_sample_fopen - An open function for "sample" debugfs interface + * @inode: The in-kernel inode representation of this debugfs "file" + * @filp: The active open file structure for the debugfs "file" + * + * This function handles opening the "sample" file within the hardware + * latency detector debugfs directory interface. This file is used to read + * raw samples from the global ring_buffer and allows the user to see a + * running latency history. Can be opened blocking or non-blocking, + * affecting whether it behaves as a buffer read pipe, or does not. + * Implements simple locking to prevent multiple simultaneous use. + */ +static int debug_sample_fopen(struct inode *inode, struct file *filp) +{ + if (!atomic_add_unless(&data.sample_open, 1, 1)) + return -EBUSY; + else + return 0; +} + +/** + * debug_sample_fread - A read function for "sample" debugfs interface + * @filp: The active open file structure for the debugfs "file" + * @ubuf: The user buffer that will contain the samples read + * @cnt: The maximum bytes to read from the debugfs "file" + * @ppos: The current position in the debugfs "file" + * + * This function handles reading from the "sample" file within the hardware + * latency detector debugfs directory interface. This file is used to read + * raw samples from the global ring_buffer and allows the user to see a + * running latency history. By default this will block pending a new + * value written into the sample buffer, unless there are already a + * number of value(s) waiting in the buffer, or the sample file was + * previously opened in a non-blocking mode of operation. + */ +static ssize_t debug_sample_fread(struct file *filp, char __user *ubuf, + size_t cnt, loff_t *ppos) +{ + int len = 0; + char buf[64]; + struct sample *sample = NULL; + + if (!enabled) + return 0; + + sample = kzalloc(sizeof(struct sample), GFP_KERNEL); + if (!sample) + return -ENOMEM; + + while (!buffer_get_sample(sample)) { + + DEFINE_WAIT(wait); + + if (filp->f_flags & O_NONBLOCK) { + len = -EAGAIN; + goto out; + } + + prepare_to_wait(&data.wq, &wait, TASK_INTERRUPTIBLE); + schedule(); + finish_wait(&data.wq, &wait); + + if (signal_pending(current)) { + len = -EINTR; + goto out; + } + + if (!enabled) { /* enable was toggled */ + len = 0; + goto out; + } + } + + len = snprintf(buf, sizeof(buf), "%010lu.%010lu\t%llu\t%llu\n", + sample->timestamp.tv_sec, + sample->timestamp.tv_nsec, + sample->duration, + sample->outer_duration); + + + /* handling partial reads is more trouble than it's worth */ + if (len > cnt) + goto out; + + if (copy_to_user(ubuf, buf, len)) + len = -EFAULT; + +out: + kfree(sample); + return len; +} + +/** + * debug_sample_release - Release function for "sample" debugfs interface + * @inode: The in-kernel inode represenation of the debugfs "file" + * @filp: The active open file structure for the debugfs "file" + * + * This function completes the close of the debugfs interface "sample" file. + * Frees the sample_open "lock" so that other users may open the interface. + */ +static int debug_sample_release(struct inode *inode, struct file *filp) +{ + atomic_dec(&data.sample_open); + + return 0; +} + +/** + * debug_threshold_fopen - Open function for "threshold" debugfs entry + * @inode: The in-kernel inode representation of the debugfs "file" + * @filp: The active open file structure for the debugfs "file" + * + * This function provides an open implementation for the "threshold" debugfs + * interface to the hardware latency detector. + */ +static int debug_threshold_fopen(struct inode *inode, struct file *filp) +{ + return 0; +} + +/** + * debug_threshold_fread - Read function for "threshold" debugfs entry + * @filp: The active open file structure for the debugfs "file" + * @ubuf: The userspace provided buffer to read value into + * @cnt: The maximum number of bytes to read + * @ppos: The current "file" position + * + * This function provides a read implementation for the "threshold" debugfs + * interface to the hardware latency detector. It can be used to determine + * the current threshold level at which a latency will be recorded in the + * global ring buffer, typically on the order of 10us. + */ +static ssize_t debug_threshold_fread(struct file *filp, char __user *ubuf, + size_t cnt, loff_t *ppos) +{ + return simple_data_read(filp, ubuf, cnt, ppos, &data.threshold); +} + +/** + * debug_threshold_fwrite - Write function for "threshold" debugfs entry + * @filp: The active open file structure for the debugfs "file" + * @ubuf: The user buffer that contains the value to write + * @cnt: The maximum number of bytes to write to "file" + * @ppos: The current position in the debugfs "file" + * + * This function provides a write implementation for the "threshold" debugfs + * interface to the hardware latency detector. It can be used to configure + * the threshold level at which any subsequently detected latencies will + * be recorded into the global ring buffer. + */ +static ssize_t debug_threshold_fwrite(struct file *filp, + const char __user *ubuf, + size_t cnt, + loff_t *ppos) +{ + int ret; + + ret = simple_data_write(filp, ubuf, cnt, ppos, &data.threshold); + + if (enabled) + wake_up_process(kthread); + + return ret; +} + +/** + * debug_width_fopen - Open function for "width" debugfs entry + * @inode: The in-kernel inode representation of the debugfs "file" + * @filp: The active open file structure for the debugfs "file" + * + * This function provides an open implementation for the "width" debugfs + * interface to the hardware latency detector. + */ +static int debug_width_fopen(struct inode *inode, struct file *filp) +{ + return 0; +} + +/** + * debug_width_fread - Read function for "width" debugfs entry + * @filp: The active open file structure for the debugfs "file" + * @ubuf: The userspace provided buffer to read value into + * @cnt: The maximum number of bytes to read + * @ppos: The current "file" position + * + * This function provides a read implementation for the "width" debugfs + * interface to the hardware latency detector. It can be used to determine + * for how many us of the total window us we will actively sample for any + * hardware-induced latecy periods. Obviously, it is not possible to + * sample constantly and have the system respond to a sample reader, or, + * worse, without having the system appear to have gone out to lunch. + */ +static ssize_t debug_width_fread(struct file *filp, char __user *ubuf, + size_t cnt, loff_t *ppos) +{ + return simple_data_read(filp, ubuf, cnt, ppos, &data.sample_width); +} + +/** + * debug_width_fwrite - Write function for "width" debugfs entry + * @filp: The active open file structure for the debugfs "file" + * @ubuf: The user buffer that contains the value to write + * @cnt: The maximum number of bytes to write to "file" + * @ppos: The current position in the debugfs "file" + * + * This function provides a write implementation for the "width" debugfs + * interface to the hardware latency detector. It can be used to configure + * for how many us of the total window us we will actively sample for any + * hardware-induced latency periods. Obviously, it is not possible to + * sample constantly and have the system respond to a sample reader, or, + * worse, without having the system appear to have gone out to lunch. It + * is enforced that width is less that the total window size. + */ +static ssize_t debug_width_fwrite(struct file *filp, + const char __user *ubuf, + size_t cnt, + loff_t *ppos) +{ + char buf[U64STR_SIZE]; + int csize = min(cnt, sizeof(buf)); + u64 val = 0; + int err = 0; + + memset(buf, '\0', sizeof(buf)); + if (copy_from_user(buf, ubuf, csize)) + return -EFAULT; + + buf[U64STR_SIZE-1] = '\0'; /* just in case */ + err = kstrtoull(buf, 10, &val); + if (0 != err) + return -EINVAL; + + mutex_lock(&data.lock); + if (val < data.sample_window) + data.sample_width = val; + else { + mutex_unlock(&data.lock); + return -EINVAL; + } + mutex_unlock(&data.lock); + + if (enabled) + wake_up_process(kthread); + + return csize; +} + +/** + * debug_window_fopen - Open function for "window" debugfs entry + * @inode: The in-kernel inode representation of the debugfs "file" + * @filp: The active open file structure for the debugfs "file" + * + * This function provides an open implementation for the "window" debugfs + * interface to the hardware latency detector. The window is the total time + * in us that will be considered one sample period. Conceptually, windows + * occur back-to-back and contain a sample width period during which + * actual sampling occurs. + */ +static int debug_window_fopen(struct inode *inode, struct file *filp) +{ + return 0; +} + +/** + * debug_window_fread - Read function for "window" debugfs entry + * @filp: The active open file structure for the debugfs "file" + * @ubuf: The userspace provided buffer to read value into + * @cnt: The maximum number of bytes to read + * @ppos: The current "file" position + * + * This function provides a read implementation for the "window" debugfs + * interface to the hardware latency detector. The window is the total time + * in us that will be considered one sample period. Conceptually, windows + * occur back-to-back and contain a sample width period during which + * actual sampling occurs. Can be used to read the total window size. + */ +static ssize_t debug_window_fread(struct file *filp, char __user *ubuf, + size_t cnt, loff_t *ppos) +{ + return simple_data_read(filp, ubuf, cnt, ppos, &data.sample_window); +} + +/** + * debug_window_fwrite - Write function for "window" debugfs entry + * @filp: The active open file structure for the debugfs "file" + * @ubuf: The user buffer that contains the value to write + * @cnt: The maximum number of bytes to write to "file" + * @ppos: The current position in the debugfs "file" + * + * This function provides a write implementation for the "window" debufds + * interface to the hardware latency detetector. The window is the total time + * in us that will be considered one sample period. Conceptually, windows + * occur back-to-back and contain a sample width period during which + * actual sampling occurs. Can be used to write a new total window size. It + * is enfoced that any value written must be greater than the sample width + * size, or an error results. + */ +static ssize_t debug_window_fwrite(struct file *filp, + const char __user *ubuf, + size_t cnt, + loff_t *ppos) +{ + char buf[U64STR_SIZE]; + int csize = min(cnt, sizeof(buf)); + u64 val = 0; + int err = 0; + + memset(buf, '\0', sizeof(buf)); + if (copy_from_user(buf, ubuf, csize)) + return -EFAULT; + + buf[U64STR_SIZE-1] = '\0'; /* just in case */ + err = kstrtoull(buf, 10, &val); + if (0 != err) + return -EINVAL; + + mutex_lock(&data.lock); + if (data.sample_width < val) + data.sample_window = val; + else { + mutex_unlock(&data.lock); + return -EINVAL; + } + mutex_unlock(&data.lock); + + return csize; +} + +/* + * Function pointers for the "count" debugfs file operations + */ +static const struct file_operations count_fops = { + .open = debug_count_fopen, + .read = debug_count_fread, + .write = debug_count_fwrite, + .owner = THIS_MODULE, +}; + +/* + * Function pointers for the "enable" debugfs file operations + */ +static const struct file_operations enable_fops = { + .open = debug_enable_fopen, + .read = debug_enable_fread, + .write = debug_enable_fwrite, + .owner = THIS_MODULE, +}; + +/* + * Function pointers for the "max" debugfs file operations + */ +static const struct file_operations max_fops = { + .open = debug_max_fopen, + .read = debug_max_fread, + .write = debug_max_fwrite, + .owner = THIS_MODULE, +}; + +/* + * Function pointers for the "sample" debugfs file operations + */ +static const struct file_operations sample_fops = { + .open = debug_sample_fopen, + .read = debug_sample_fread, + .release = debug_sample_release, + .owner = THIS_MODULE, +}; + +/* + * Function pointers for the "threshold" debugfs file operations + */ +static const struct file_operations threshold_fops = { + .open = debug_threshold_fopen, + .read = debug_threshold_fread, + .write = debug_threshold_fwrite, + .owner = THIS_MODULE, +}; + +/* + * Function pointers for the "width" debugfs file operations + */ +static const struct file_operations width_fops = { + .open = debug_width_fopen, + .read = debug_width_fread, + .write = debug_width_fwrite, + .owner = THIS_MODULE, +}; + +/* + * Function pointers for the "window" debugfs file operations + */ +static const struct file_operations window_fops = { + .open = debug_window_fopen, + .read = debug_window_fread, + .write = debug_window_fwrite, + .owner = THIS_MODULE, +}; + +/** + * init_debugfs - A function to initialize the debugfs interface files + * + * This function creates entries in debugfs for "hwlat_detector", including + * files to read values from the detector, current samples, and the + * maximum sample that has been captured since the hardware latency + * dectector was started. + */ +static int init_debugfs(void) +{ + int ret = -ENOMEM; + + debug_dir = debugfs_create_dir(DRVNAME, NULL); + if (!debug_dir) + goto err_debug_dir; + + debug_sample = debugfs_create_file("sample", 0444, + debug_dir, NULL, + &sample_fops); + if (!debug_sample) + goto err_sample; + + debug_count = debugfs_create_file("count", 0444, + debug_dir, NULL, + &count_fops); + if (!debug_count) + goto err_count; + + debug_max = debugfs_create_file("max", 0444, + debug_dir, NULL, + &max_fops); + if (!debug_max) + goto err_max; + + debug_sample_window = debugfs_create_file("window", 0644, + debug_dir, NULL, + &window_fops); + if (!debug_sample_window) + goto err_window; + + debug_sample_width = debugfs_create_file("width", 0644, + debug_dir, NULL, + &width_fops); + if (!debug_sample_width) + goto err_width; + + debug_threshold = debugfs_create_file("threshold", 0644, + debug_dir, NULL, + &threshold_fops); + if (!debug_threshold) + goto err_threshold; + + debug_enable = debugfs_create_file("enable", 0644, + debug_dir, &enabled, + &enable_fops); + if (!debug_enable) + goto err_enable; + + else { + ret = 0; + goto out; + } + +err_enable: + debugfs_remove(debug_threshold); +err_threshold: + debugfs_remove(debug_sample_width); +err_width: + debugfs_remove(debug_sample_window); +err_window: + debugfs_remove(debug_max); +err_max: + debugfs_remove(debug_count); +err_count: + debugfs_remove(debug_sample); +err_sample: + debugfs_remove(debug_dir); +err_debug_dir: +out: + return ret; +} + +/** + * free_debugfs - A function to cleanup the debugfs file interface + */ +static void free_debugfs(void) +{ + /* could also use a debugfs_remove_recursive */ + debugfs_remove(debug_enable); + debugfs_remove(debug_threshold); + debugfs_remove(debug_sample_width); + debugfs_remove(debug_sample_window); + debugfs_remove(debug_max); + debugfs_remove(debug_count); + debugfs_remove(debug_sample); + debugfs_remove(debug_dir); +} + +/** + * detector_init - Standard module initialization code + */ +static int detector_init(void) +{ + int ret = -ENOMEM; + + pr_info(BANNER "version %s\n", VERSION); + + ret = init_stats(); + if (0 != ret) + goto out; + + ret = init_debugfs(); + if (0 != ret) + goto err_stats; + + if (enabled) + ret = start_kthread(); + + goto out; + +err_stats: + ring_buffer_free(ring_buffer); +out: + return ret; + +} + +/** + * detector_exit - Standard module cleanup code + */ +static void detector_exit(void) +{ + int err; + + if (enabled) { + enabled = 0; + err = stop_kthread(); + if (err) + pr_err(BANNER "cannot stop kthread\n"); + } + + free_debugfs(); + ring_buffer_free(ring_buffer); /* free up the ring buffer */ + +} + +module_init(detector_init); +module_exit(detector_exit); diff -Nur linux-3.18.14.orig/drivers/misc/Kconfig linux-3.18.14-rt/drivers/misc/Kconfig --- linux-3.18.14.orig/drivers/misc/Kconfig 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/drivers/misc/Kconfig 2015-05-31 15:32:47.297635378 -0500 @@ -54,6 +54,7 @@ config ATMEL_TCLIB bool "Atmel AT32/AT91 Timer/Counter Library" depends on (AVR32 || ARCH_AT91) + default y if PREEMPT_RT_FULL help Select this if you want a library to allocate the Timer/Counter blocks found on many Atmel processors. This facilitates using @@ -69,8 +70,7 @@ are combined to make a single 32-bit timer. When GENERIC_CLOCKEVENTS is defined, the third timer channel - may be used as a clock event device supporting oneshot mode - (delays of up to two seconds) based on the 32 KiHz clock. + may be used as a clock event device supporting oneshot mode. config ATMEL_TCB_CLKSRC_BLOCK int @@ -84,6 +84,15 @@ TC can be used for other purposes, such as PWM generation and interval timing. +config ATMEL_TCB_CLKSRC_USE_SLOW_CLOCK + bool "TC Block use 32 KiHz clock" + depends on ATMEL_TCB_CLKSRC + default y if !PREEMPT_RT_FULL + help + Select this to use 32 KiHz base clock rate as TC block clock + source for clock events. + + config DUMMY_IRQ tristate "Dummy IRQ handler" default n @@ -113,6 +122,35 @@ for information on the specific driver level and support statement for your IBM server. +config HWLAT_DETECTOR + tristate "Testing module to detect hardware-induced latencies" + depends on DEBUG_FS + depends on RING_BUFFER + default m + ---help--- + A simple hardware latency detector. Use this module to detect + large latencies introduced by the behavior of the underlying + system firmware external to Linux. We do this using periodic + use of stop_machine to grab all available CPUs and measure + for unexplainable gaps in the CPU timestamp counter(s). By + default, the module is not enabled until the "enable" file + within the "hwlat_detector" debugfs directory is toggled. + + This module is often used to detect SMI (System Management + Interrupts) on x86 systems, though is not x86 specific. To + this end, we default to using a sample window of 1 second, + during which we will sample for 0.5 seconds. If an SMI or + similar event occurs during that time, it is recorded + into an 8K samples global ring buffer until retreived. + + WARNING: This software should never be enabled (it can be built + but should not be turned on after it is loaded) in a production + environment where high latencies are a concern since the + sampling mechanism actually introduces latencies for + regular tasks while the CPU(s) are being held. + + If unsure, say N + config PHANTOM tristate "Sensable PHANToM (PCI)" depends on PCI diff -Nur linux-3.18.14.orig/drivers/misc/Makefile linux-3.18.14-rt/drivers/misc/Makefile --- linux-3.18.14.orig/drivers/misc/Makefile 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/drivers/misc/Makefile 2015-05-31 15:32:47.349635377 -0500 @@ -38,6 +38,7 @@ obj-$(CONFIG_HMC6352) += hmc6352.o obj-y += eeprom/ obj-y += cb710/ +obj-$(CONFIG_HWLAT_DETECTOR) += hwlat_detector.o obj-$(CONFIG_SPEAR13XX_PCIE_GADGET) += spear13xx_pcie_gadget.o obj-$(CONFIG_VMWARE_BALLOON) += vmw_balloon.o obj-$(CONFIG_ARM_CHARLCD) += arm-charlcd.o diff -Nur linux-3.18.14.orig/drivers/mmc/host/mmci.c linux-3.18.14-rt/drivers/mmc/host/mmci.c --- linux-3.18.14.orig/drivers/mmc/host/mmci.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/drivers/mmc/host/mmci.c 2015-05-31 15:32:47.393635377 -0500 @@ -1153,15 +1153,12 @@ struct sg_mapping_iter *sg_miter = &host->sg_miter; struct variant_data *variant = host->variant; void __iomem *base = host->base; - unsigned long flags; u32 status; status = readl(base + MMCISTATUS); dev_dbg(mmc_dev(host->mmc), "irq1 (pio) %08x\n", status); - local_irq_save(flags); - do { unsigned int remain, len; char *buffer; @@ -1201,8 +1198,6 @@ sg_miter_stop(sg_miter); - local_irq_restore(flags); - /* * If we have less than the fifo 'half-full' threshold to transfer, * trigger a PIO interrupt as soon as any data is available. diff -Nur linux-3.18.14.orig/drivers/mmc/host/sdhci.c linux-3.18.14-rt/drivers/mmc/host/sdhci.c --- linux-3.18.14.orig/drivers/mmc/host/sdhci.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/drivers/mmc/host/sdhci.c 2015-05-31 15:32:47.397635376 -0500 @@ -2565,6 +2565,31 @@ return isr ? IRQ_HANDLED : IRQ_NONE; } +#ifdef CONFIG_PREEMPT_RT_BASE +static irqreturn_t sdhci_rt_irq(int irq, void *dev_id) +{ + irqreturn_t ret; + + local_bh_disable(); + ret = sdhci_irq(irq, dev_id); + local_bh_enable(); + if (ret == IRQ_WAKE_THREAD) + ret = sdhci_thread_irq(irq, dev_id); + return ret; +} +#endif + +static int sdhci_req_irq(struct sdhci_host *host) +{ +#ifdef CONFIG_PREEMPT_RT_BASE + return request_threaded_irq(host->irq, NULL, sdhci_rt_irq, + IRQF_SHARED, mmc_hostname(host->mmc), host); +#else + return request_threaded_irq(host->irq, sdhci_irq, sdhci_thread_irq, + IRQF_SHARED, mmc_hostname(host->mmc), host); +#endif +} + /*****************************************************************************\ * * * Suspend/resume * @@ -2632,9 +2657,7 @@ } if (!device_may_wakeup(mmc_dev(host->mmc))) { - ret = request_threaded_irq(host->irq, sdhci_irq, - sdhci_thread_irq, IRQF_SHARED, - mmc_hostname(host->mmc), host); + ret = sdhci_req_irq(host); if (ret) return ret; } else { @@ -3253,8 +3276,7 @@ sdhci_init(host, 0); - ret = request_threaded_irq(host->irq, sdhci_irq, sdhci_thread_irq, - IRQF_SHARED, mmc_hostname(mmc), host); + ret = sdhci_req_irq(host); if (ret) { pr_err("%s: Failed to request IRQ %d: %d\n", mmc_hostname(mmc), host->irq, ret); diff -Nur linux-3.18.14.orig/drivers/net/ethernet/3com/3c59x.c linux-3.18.14-rt/drivers/net/ethernet/3com/3c59x.c --- linux-3.18.14.orig/drivers/net/ethernet/3com/3c59x.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/drivers/net/ethernet/3com/3c59x.c 2015-05-31 15:32:47.425635376 -0500 @@ -842,9 +842,9 @@ { struct vortex_private *vp = netdev_priv(dev); unsigned long flags; - local_irq_save(flags); + local_irq_save_nort(flags); (vp->full_bus_master_rx ? boomerang_interrupt:vortex_interrupt)(dev->irq,dev); - local_irq_restore(flags); + local_irq_restore_nort(flags); } #endif @@ -1916,12 +1916,12 @@ * Block interrupts because vortex_interrupt does a bare spin_lock() */ unsigned long flags; - local_irq_save(flags); + local_irq_save_nort(flags); if (vp->full_bus_master_tx) boomerang_interrupt(dev->irq, dev); else vortex_interrupt(dev->irq, dev); - local_irq_restore(flags); + local_irq_restore_nort(flags); } } diff -Nur linux-3.18.14.orig/drivers/net/ethernet/atheros/atl1c/atl1c_main.c linux-3.18.14-rt/drivers/net/ethernet/atheros/atl1c/atl1c_main.c --- linux-3.18.14.orig/drivers/net/ethernet/atheros/atl1c/atl1c_main.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/drivers/net/ethernet/atheros/atl1c/atl1c_main.c 2015-05-31 15:32:47.437635376 -0500 @@ -2213,11 +2213,7 @@ } tpd_req = atl1c_cal_tpd_req(skb); - if (!spin_trylock_irqsave(&adapter->tx_lock, flags)) { - if (netif_msg_pktdata(adapter)) - dev_info(&adapter->pdev->dev, "tx locked\n"); - return NETDEV_TX_LOCKED; - } + spin_lock_irqsave(&adapter->tx_lock, flags); if (atl1c_tpd_avail(adapter, type) < tpd_req) { /* no enough descriptor, just stop queue */ diff -Nur linux-3.18.14.orig/drivers/net/ethernet/atheros/atl1e/atl1e_main.c linux-3.18.14-rt/drivers/net/ethernet/atheros/atl1e/atl1e_main.c --- linux-3.18.14.orig/drivers/net/ethernet/atheros/atl1e/atl1e_main.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/drivers/net/ethernet/atheros/atl1e/atl1e_main.c 2015-05-31 15:32:47.445635376 -0500 @@ -1880,8 +1880,7 @@ return NETDEV_TX_OK; } tpd_req = atl1e_cal_tdp_req(skb); - if (!spin_trylock_irqsave(&adapter->tx_lock, flags)) - return NETDEV_TX_LOCKED; + spin_lock_irqsave(&adapter->tx_lock, flags); if (atl1e_tpd_avail(adapter) < tpd_req) { /* no enough descriptor, just stop queue */ diff -Nur linux-3.18.14.orig/drivers/net/ethernet/chelsio/cxgb/sge.c linux-3.18.14-rt/drivers/net/ethernet/chelsio/cxgb/sge.c --- linux-3.18.14.orig/drivers/net/ethernet/chelsio/cxgb/sge.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/drivers/net/ethernet/chelsio/cxgb/sge.c 2015-05-31 15:32:47.493635375 -0500 @@ -1663,8 +1663,7 @@ struct cmdQ *q = &sge->cmdQ[qid]; unsigned int credits, pidx, genbit, count, use_sched_skb = 0; - if (!spin_trylock(&q->lock)) - return NETDEV_TX_LOCKED; + spin_lock(&q->lock); reclaim_completed_tx(sge, q); diff -Nur linux-3.18.14.orig/drivers/net/ethernet/freescale/gianfar.c linux-3.18.14-rt/drivers/net/ethernet/freescale/gianfar.c --- linux-3.18.14.orig/drivers/net/ethernet/freescale/gianfar.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/drivers/net/ethernet/freescale/gianfar.c 2015-05-31 15:32:47.525635375 -0500 @@ -1483,7 +1483,7 @@ if (netif_running(ndev)) { - local_irq_save(flags); + local_irq_save_nort(flags); lock_tx_qs(priv); gfar_halt_nodisable(priv); @@ -1499,7 +1499,7 @@ gfar_write(®s->maccfg1, tempval); unlock_tx_qs(priv); - local_irq_restore(flags); + local_irq_restore_nort(flags); disable_napi(priv); @@ -1541,7 +1541,7 @@ /* Disable Magic Packet mode, in case something * else woke us up. */ - local_irq_save(flags); + local_irq_save_nort(flags); lock_tx_qs(priv); tempval = gfar_read(®s->maccfg2); @@ -1551,7 +1551,7 @@ gfar_start(priv); unlock_tx_qs(priv); - local_irq_restore(flags); + local_irq_restore_nort(flags); netif_device_attach(ndev); @@ -3307,14 +3307,14 @@ dev->stats.tx_dropped++; atomic64_inc(&priv->extra_stats.tx_underrun); - local_irq_save(flags); + local_irq_save_nort(flags); lock_tx_qs(priv); /* Reactivate the Tx Queues */ gfar_write(®s->tstat, gfargrp->tstat); unlock_tx_qs(priv); - local_irq_restore(flags); + local_irq_restore_nort(flags); } netif_dbg(priv, tx_err, dev, "Transmit Error\n"); } diff -Nur linux-3.18.14.orig/drivers/net/ethernet/neterion/s2io.c linux-3.18.14-rt/drivers/net/ethernet/neterion/s2io.c --- linux-3.18.14.orig/drivers/net/ethernet/neterion/s2io.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/drivers/net/ethernet/neterion/s2io.c 2015-05-31 15:32:47.537635375 -0500 @@ -4084,12 +4084,7 @@ [skb->priority & (MAX_TX_FIFOS - 1)]; fifo = &mac_control->fifos[queue]; - if (do_spin_lock) - spin_lock_irqsave(&fifo->tx_lock, flags); - else { - if (unlikely(!spin_trylock_irqsave(&fifo->tx_lock, flags))) - return NETDEV_TX_LOCKED; - } + spin_lock_irqsave(&fifo->tx_lock, flags); if (sp->config.multiq) { if (__netif_subqueue_stopped(dev, fifo->fifo_no)) { diff -Nur linux-3.18.14.orig/drivers/net/ethernet/oki-semi/pch_gbe/pch_gbe_main.c linux-3.18.14-rt/drivers/net/ethernet/oki-semi/pch_gbe/pch_gbe_main.c --- linux-3.18.14.orig/drivers/net/ethernet/oki-semi/pch_gbe/pch_gbe_main.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/drivers/net/ethernet/oki-semi/pch_gbe/pch_gbe_main.c 2015-05-31 15:32:47.549635375 -0500 @@ -2137,10 +2137,8 @@ struct pch_gbe_tx_ring *tx_ring = adapter->tx_ring; unsigned long flags; - if (!spin_trylock_irqsave(&tx_ring->tx_lock, flags)) { - /* Collision - tell upper layer to requeue */ - return NETDEV_TX_LOCKED; - } + spin_lock_irqsave(&tx_ring->tx_lock, flags); + if (unlikely(!PCH_GBE_DESC_UNUSED(tx_ring))) { netif_stop_queue(netdev); spin_unlock_irqrestore(&tx_ring->tx_lock, flags); diff -Nur linux-3.18.14.orig/drivers/net/ethernet/realtek/8139too.c linux-3.18.14-rt/drivers/net/ethernet/realtek/8139too.c --- linux-3.18.14.orig/drivers/net/ethernet/realtek/8139too.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/drivers/net/ethernet/realtek/8139too.c 2015-05-31 15:32:47.557635375 -0500 @@ -2215,7 +2215,7 @@ struct rtl8139_private *tp = netdev_priv(dev); const int irq = tp->pci_dev->irq; - disable_irq(irq); + disable_irq_nosync(irq); rtl8139_interrupt(irq, dev); enable_irq(irq); } diff -Nur linux-3.18.14.orig/drivers/net/ethernet/tehuti/tehuti.c linux-3.18.14-rt/drivers/net/ethernet/tehuti/tehuti.c --- linux-3.18.14.orig/drivers/net/ethernet/tehuti/tehuti.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/drivers/net/ethernet/tehuti/tehuti.c 2015-05-31 15:32:47.581635375 -0500 @@ -1629,13 +1629,8 @@ unsigned long flags; ENTER; - local_irq_save(flags); - if (!spin_trylock(&priv->tx_lock)) { - local_irq_restore(flags); - DBG("%s[%s]: TX locked, returning NETDEV_TX_LOCKED\n", - BDX_DRV_NAME, ndev->name); - return NETDEV_TX_LOCKED; - } + + spin_lock_irqsave(&priv->tx_lock, flags); /* build tx descriptor */ BDX_ASSERT(f->m.wptr >= f->m.memsz); /* started with valid wptr */ diff -Nur linux-3.18.14.orig/drivers/net/rionet.c linux-3.18.14-rt/drivers/net/rionet.c --- linux-3.18.14.orig/drivers/net/rionet.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/drivers/net/rionet.c 2015-05-31 15:32:47.597635374 -0500 @@ -174,11 +174,7 @@ unsigned long flags; int add_num = 1; - local_irq_save(flags); - if (!spin_trylock(&rnet->tx_lock)) { - local_irq_restore(flags); - return NETDEV_TX_LOCKED; - } + spin_lock_irqsave(&rnet->tx_lock, flags); if (is_multicast_ether_addr(eth->h_dest)) add_num = nets[rnet->mport->id].nact; diff -Nur linux-3.18.14.orig/drivers/net/wireless/orinoco/orinoco_usb.c linux-3.18.14-rt/drivers/net/wireless/orinoco/orinoco_usb.c --- linux-3.18.14.orig/drivers/net/wireless/orinoco/orinoco_usb.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/drivers/net/wireless/orinoco/orinoco_usb.c 2015-05-31 15:32:47.613635374 -0500 @@ -699,7 +699,7 @@ while (!ctx->done.done && msecs--) udelay(1000); } else { - wait_event_interruptible(ctx->done.wait, + swait_event_interruptible(ctx->done.wait, ctx->done.done); } break; diff -Nur linux-3.18.14.orig/drivers/pci/access.c linux-3.18.14-rt/drivers/pci/access.c --- linux-3.18.14.orig/drivers/pci/access.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/drivers/pci/access.c 2015-05-31 15:32:47.665635374 -0500 @@ -434,7 +434,7 @@ WARN_ON(!dev->block_cfg_access); dev->block_cfg_access = 0; - wake_up_all(&pci_cfg_wait); + wake_up_all_locked(&pci_cfg_wait); raw_spin_unlock_irqrestore(&pci_lock, flags); } EXPORT_SYMBOL_GPL(pci_cfg_access_unlock); diff -Nur linux-3.18.14.orig/drivers/scsi/fcoe/fcoe.c linux-3.18.14-rt/drivers/scsi/fcoe/fcoe.c --- linux-3.18.14.orig/drivers/scsi/fcoe/fcoe.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/drivers/scsi/fcoe/fcoe.c 2015-05-31 15:32:47.677635374 -0500 @@ -1286,7 +1286,7 @@ struct sk_buff *skb; #ifdef CONFIG_SMP struct fcoe_percpu_s *p0; - unsigned targ_cpu = get_cpu(); + unsigned targ_cpu = get_cpu_light(); #endif /* CONFIG_SMP */ FCOE_DBG("Destroying receive thread for CPU %d\n", cpu); @@ -1342,7 +1342,7 @@ kfree_skb(skb); spin_unlock_bh(&p->fcoe_rx_list.lock); } - put_cpu(); + put_cpu_light(); #else /* * This a non-SMP scenario where the singular Rx thread is @@ -1566,11 +1566,11 @@ static int fcoe_alloc_paged_crc_eof(struct sk_buff *skb, int tlen) { struct fcoe_percpu_s *fps; - int rc; + int rc, cpu = get_cpu_light(); - fps = &get_cpu_var(fcoe_percpu); + fps = &per_cpu(fcoe_percpu, cpu); rc = fcoe_get_paged_crc_eof(skb, tlen, fps); - put_cpu_var(fcoe_percpu); + put_cpu_light(); return rc; } @@ -1768,11 +1768,11 @@ return 0; } - stats = per_cpu_ptr(lport->stats, get_cpu()); + stats = per_cpu_ptr(lport->stats, get_cpu_light()); stats->InvalidCRCCount++; if (stats->InvalidCRCCount < 5) printk(KERN_WARNING "fcoe: dropping frame with CRC error\n"); - put_cpu(); + put_cpu_light(); return -EINVAL; } @@ -1848,13 +1848,13 @@ goto drop; if (!fcoe_filter_frames(lport, fp)) { - put_cpu(); + put_cpu_light(); fc_exch_recv(lport, fp); return; } drop: stats->ErrorFrames++; - put_cpu(); + put_cpu_light(); kfree_skb(skb); } diff -Nur linux-3.18.14.orig/drivers/scsi/fcoe/fcoe_ctlr.c linux-3.18.14-rt/drivers/scsi/fcoe/fcoe_ctlr.c --- linux-3.18.14.orig/drivers/scsi/fcoe/fcoe_ctlr.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/drivers/scsi/fcoe/fcoe_ctlr.c 2015-05-31 15:32:47.681635374 -0500 @@ -831,7 +831,7 @@ INIT_LIST_HEAD(&del_list); - stats = per_cpu_ptr(fip->lp->stats, get_cpu()); + stats = per_cpu_ptr(fip->lp->stats, get_cpu_light()); list_for_each_entry_safe(fcf, next, &fip->fcfs, list) { deadline = fcf->time + fcf->fka_period + fcf->fka_period / 2; @@ -867,7 +867,7 @@ sel_time = fcf->time; } } - put_cpu(); + put_cpu_light(); list_for_each_entry_safe(fcf, next, &del_list, list) { /* Removes fcf from current list */ diff -Nur linux-3.18.14.orig/drivers/scsi/libfc/fc_exch.c linux-3.18.14-rt/drivers/scsi/libfc/fc_exch.c --- linux-3.18.14.orig/drivers/scsi/libfc/fc_exch.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/drivers/scsi/libfc/fc_exch.c 2015-05-31 15:32:47.689635374 -0500 @@ -816,10 +816,10 @@ } memset(ep, 0, sizeof(*ep)); - cpu = get_cpu(); + cpu = get_cpu_light(); pool = per_cpu_ptr(mp->pool, cpu); spin_lock_bh(&pool->lock); - put_cpu(); + put_cpu_light(); /* peek cache of free slot */ if (pool->left != FC_XID_UNKNOWN) { diff -Nur linux-3.18.14.orig/drivers/scsi/libsas/sas_ata.c linux-3.18.14-rt/drivers/scsi/libsas/sas_ata.c --- linux-3.18.14.orig/drivers/scsi/libsas/sas_ata.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/drivers/scsi/libsas/sas_ata.c 2015-05-31 15:32:47.689635374 -0500 @@ -191,7 +191,7 @@ /* TODO: audit callers to ensure they are ready for qc_issue to * unconditionally re-enable interrupts */ - local_irq_save(flags); + local_irq_save_nort(flags); spin_unlock(ap->lock); /* If the device fell off, no sense in issuing commands */ @@ -261,7 +261,7 @@ out: spin_lock(ap->lock); - local_irq_restore(flags); + local_irq_restore_nort(flags); return ret; } diff -Nur linux-3.18.14.orig/drivers/scsi/qla2xxx/qla_inline.h linux-3.18.14-rt/drivers/scsi/qla2xxx/qla_inline.h --- linux-3.18.14.orig/drivers/scsi/qla2xxx/qla_inline.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/drivers/scsi/qla2xxx/qla_inline.h 2015-05-31 15:32:47.693635374 -0500 @@ -59,12 +59,12 @@ { unsigned long flags; struct qla_hw_data *ha = rsp->hw; - local_irq_save(flags); + local_irq_save_nort(flags); if (IS_P3P_TYPE(ha)) qla82xx_poll(0, rsp); else ha->isp_ops->intr_handler(0, rsp); - local_irq_restore(flags); + local_irq_restore_nort(flags); } static inline uint8_t * diff -Nur linux-3.18.14.orig/drivers/thermal/x86_pkg_temp_thermal.c linux-3.18.14-rt/drivers/thermal/x86_pkg_temp_thermal.c --- linux-3.18.14.orig/drivers/thermal/x86_pkg_temp_thermal.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/drivers/thermal/x86_pkg_temp_thermal.c 2015-05-31 15:32:47.701635374 -0500 @@ -29,6 +29,7 @@ #include #include #include +#include #include #include @@ -352,7 +353,7 @@ } } -static int pkg_temp_thermal_platform_thermal_notify(__u64 msr_val) +static void platform_thermal_notify_work(struct swork_event *event) { unsigned long flags; int cpu = smp_processor_id(); @@ -369,7 +370,7 @@ pkg_work_scheduled[phy_id]) { disable_pkg_thres_interrupt(); spin_unlock_irqrestore(&pkg_work_lock, flags); - return -EINVAL; + return; } pkg_work_scheduled[phy_id] = 1; spin_unlock_irqrestore(&pkg_work_lock, flags); @@ -378,9 +379,48 @@ schedule_delayed_work_on(cpu, &per_cpu(pkg_temp_thermal_threshold_work, cpu), msecs_to_jiffies(notify_delay_ms)); +} + +#ifdef CONFIG_PREEMPT_RT_FULL +static struct swork_event notify_work; + +static int thermal_notify_work_init(void) +{ + int err; + + err = swork_get(); + if (err) + return err; + + INIT_SWORK(¬ify_work, platform_thermal_notify_work); return 0; } +static void thermal_notify_work_cleanup(void) +{ + swork_put(); +} + +static int pkg_temp_thermal_platform_thermal_notify(__u64 msr_val) +{ + swork_queue(¬ify_work); + return 0; +} + +#else /* !CONFIG_PREEMPT_RT_FULL */ + +static int thermal_notify_work_init(void) { return 0; } + +static int thermal_notify_work_cleanup(void) { } + +static int pkg_temp_thermal_platform_thermal_notify(__u64 msr_val) +{ + platform_thermal_notify_work(NULL); + + return 0; +} +#endif /* CONFIG_PREEMPT_RT_FULL */ + static int find_siblings_cpu(int cpu) { int i; @@ -584,6 +624,9 @@ if (!x86_match_cpu(pkg_temp_thermal_ids)) return -ENODEV; + if (!thermal_notify_work_init()) + return -ENODEV; + spin_lock_init(&pkg_work_lock); platform_thermal_package_notify = pkg_temp_thermal_platform_thermal_notify; @@ -608,7 +651,7 @@ kfree(pkg_work_scheduled); platform_thermal_package_notify = NULL; platform_thermal_package_rate_control = NULL; - + thermal_notify_work_cleanup(); return -ENODEV; } @@ -633,6 +676,7 @@ mutex_unlock(&phy_dev_list_mutex); platform_thermal_package_notify = NULL; platform_thermal_package_rate_control = NULL; + thermal_notify_work_cleanup(); for_each_online_cpu(i) cancel_delayed_work_sync( &per_cpu(pkg_temp_thermal_threshold_work, i)); diff -Nur linux-3.18.14.orig/drivers/tty/serial/8250/8250_core.c linux-3.18.14-rt/drivers/tty/serial/8250/8250_core.c --- linux-3.18.14.orig/drivers/tty/serial/8250/8250_core.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/drivers/tty/serial/8250/8250_core.c 2015-05-31 15:32:47.753635373 -0500 @@ -37,6 +37,7 @@ #include #include #include +#include #include #include #ifdef CONFIG_SPARC @@ -81,7 +82,16 @@ #define DEBUG_INTR(fmt...) do { } while (0) #endif -#define PASS_LIMIT 512 +/* + * On -rt we can have a more delays, and legitimately + * so - so don't drop work spuriously and spam the + * syslog: + */ +#ifdef CONFIG_PREEMPT_RT_FULL +# define PASS_LIMIT 1000000 +#else +# define PASS_LIMIT 512 +#endif #define BOTH_EMPTY (UART_LSR_TEMT | UART_LSR_THRE) @@ -3197,7 +3207,7 @@ serial8250_rpm_get(up); - if (port->sysrq || oops_in_progress) + if (port->sysrq || oops_in_progress || in_kdb_printk()) locked = spin_trylock_irqsave(&port->lock, flags); else spin_lock_irqsave(&port->lock, flags); diff -Nur linux-3.18.14.orig/drivers/tty/serial/amba-pl011.c linux-3.18.14-rt/drivers/tty/serial/amba-pl011.c --- linux-3.18.14.orig/drivers/tty/serial/amba-pl011.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/drivers/tty/serial/amba-pl011.c 2015-05-31 15:32:47.777635373 -0500 @@ -1935,13 +1935,19 @@ clk_enable(uap->clk); - local_irq_save(flags); + /* + * local_irq_save(flags); + * + * This local_irq_save() is nonsense. If we come in via sysrq + * handling then interrupts are already disabled. Aside of + * that the port.sysrq check is racy on SMP regardless. + */ if (uap->port.sysrq) locked = 0; else if (oops_in_progress) - locked = spin_trylock(&uap->port.lock); + locked = spin_trylock_irqsave(&uap->port.lock, flags); else - spin_lock(&uap->port.lock); + spin_lock_irqsave(&uap->port.lock, flags); /* * First save the CR then disable the interrupts @@ -1963,8 +1969,7 @@ writew(old_cr, uap->port.membase + UART011_CR); if (locked) - spin_unlock(&uap->port.lock); - local_irq_restore(flags); + spin_unlock_irqrestore(&uap->port.lock, flags); clk_disable(uap->clk); } diff -Nur linux-3.18.14.orig/drivers/tty/serial/omap-serial.c linux-3.18.14-rt/drivers/tty/serial/omap-serial.c --- linux-3.18.14.orig/drivers/tty/serial/omap-serial.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/drivers/tty/serial/omap-serial.c 2015-05-31 15:32:47.781635373 -0500 @@ -1270,13 +1270,10 @@ pm_runtime_get_sync(up->dev); - local_irq_save(flags); - if (up->port.sysrq) - locked = 0; - else if (oops_in_progress) - locked = spin_trylock(&up->port.lock); + if (up->port.sysrq || oops_in_progress) + locked = spin_trylock_irqsave(&up->port.lock, flags); else - spin_lock(&up->port.lock); + spin_lock_irqsave(&up->port.lock, flags); /* * First save the IER then disable the interrupts @@ -1305,8 +1302,7 @@ pm_runtime_mark_last_busy(up->dev); pm_runtime_put_autosuspend(up->dev); if (locked) - spin_unlock(&up->port.lock); - local_irq_restore(flags); + spin_unlock_irqrestore(&up->port.lock, flags); } static int __init diff -Nur linux-3.18.14.orig/drivers/usb/core/hcd.c linux-3.18.14-rt/drivers/usb/core/hcd.c --- linux-3.18.14.orig/drivers/usb/core/hcd.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/drivers/usb/core/hcd.c 2015-05-31 15:32:47.785635373 -0500 @@ -1681,9 +1681,9 @@ * and no one may trigger the above deadlock situation when * running complete() in tasklet. */ - local_irq_save(flags); + local_irq_save_nort(flags); urb->complete(urb); - local_irq_restore(flags); + local_irq_restore_nort(flags); usb_anchor_resume_wakeups(anchor); atomic_dec(&urb->use_count); diff -Nur linux-3.18.14.orig/drivers/usb/gadget/function/f_fs.c linux-3.18.14-rt/drivers/usb/gadget/function/f_fs.c --- linux-3.18.14.orig/drivers/usb/gadget/function/f_fs.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/drivers/usb/gadget/function/f_fs.c 2015-05-31 15:32:47.809635373 -0500 @@ -1428,7 +1428,7 @@ pr_info("%s(): freeing\n", __func__); ffs_data_clear(ffs); BUG_ON(waitqueue_active(&ffs->ev.waitq) || - waitqueue_active(&ffs->ep0req_completion.wait)); + swaitqueue_active(&ffs->ep0req_completion.wait)); kfree(ffs->dev_name); kfree(ffs); } diff -Nur linux-3.18.14.orig/drivers/usb/gadget/legacy/inode.c linux-3.18.14-rt/drivers/usb/gadget/legacy/inode.c --- linux-3.18.14.orig/drivers/usb/gadget/legacy/inode.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/drivers/usb/gadget/legacy/inode.c 2015-05-31 15:32:47.837635372 -0500 @@ -339,7 +339,7 @@ spin_unlock_irq (&epdata->dev->lock); if (likely (value == 0)) { - value = wait_event_interruptible (done.wait, done.done); + value = swait_event_interruptible (done.wait, done.done); if (value != 0) { spin_lock_irq (&epdata->dev->lock); if (likely (epdata->ep != NULL)) { @@ -348,7 +348,7 @@ usb_ep_dequeue (epdata->ep, epdata->req); spin_unlock_irq (&epdata->dev->lock); - wait_event (done.wait, done.done); + swait_event (done.wait, done.done); if (epdata->status == -ECONNRESET) epdata->status = -EINTR; } else { diff -Nur linux-3.18.14.orig/fs/aio.c linux-3.18.14-rt/fs/aio.c --- linux-3.18.14.orig/fs/aio.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/fs/aio.c 2015-05-31 15:32:47.853635372 -0500 @@ -40,6 +40,7 @@ #include #include #include +#include #include #include @@ -110,7 +111,7 @@ struct page **ring_pages; long nr_pages; - struct work_struct free_work; + struct swork_event free_work; /* * signals when all in-flight requests are done @@ -226,6 +227,7 @@ .mount = aio_mount, .kill_sb = kill_anon_super, }; + BUG_ON(swork_get()); aio_mnt = kern_mount(&aio_fs); if (IS_ERR(aio_mnt)) panic("Failed to create aio fs mount."); @@ -505,9 +507,9 @@ return cancel(kiocb); } -static void free_ioctx(struct work_struct *work) +static void free_ioctx(struct swork_event *sev) { - struct kioctx *ctx = container_of(work, struct kioctx, free_work); + struct kioctx *ctx = container_of(sev, struct kioctx, free_work); pr_debug("freeing %p\n", ctx); @@ -526,8 +528,8 @@ if (ctx->requests_done) complete(ctx->requests_done); - INIT_WORK(&ctx->free_work, free_ioctx); - schedule_work(&ctx->free_work); + INIT_SWORK(&ctx->free_work, free_ioctx); + swork_queue(&ctx->free_work); } /* @@ -535,9 +537,9 @@ * and ctx->users has dropped to 0, so we know no more kiocbs can be submitted - * now it's safe to cancel any that need to be. */ -static void free_ioctx_users(struct percpu_ref *ref) +static void free_ioctx_users_work(struct swork_event *sev) { - struct kioctx *ctx = container_of(ref, struct kioctx, users); + struct kioctx *ctx = container_of(sev, struct kioctx, free_work); struct kiocb *req; spin_lock_irq(&ctx->ctx_lock); @@ -556,6 +558,14 @@ percpu_ref_put(&ctx->reqs); } +static void free_ioctx_users(struct percpu_ref *ref) +{ + struct kioctx *ctx = container_of(ref, struct kioctx, users); + + INIT_SWORK(&ctx->free_work, free_ioctx_users_work); + swork_queue(&ctx->free_work); +} + static int ioctx_add_table(struct kioctx *ctx, struct mm_struct *mm) { unsigned i, new_nr; diff -Nur linux-3.18.14.orig/fs/autofs4/autofs_i.h linux-3.18.14-rt/fs/autofs4/autofs_i.h --- linux-3.18.14.orig/fs/autofs4/autofs_i.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/fs/autofs4/autofs_i.h 2015-05-31 15:32:47.865635372 -0500 @@ -34,6 +34,7 @@ #include #include #include +#include #include #include diff -Nur linux-3.18.14.orig/fs/autofs4/expire.c linux-3.18.14-rt/fs/autofs4/expire.c --- linux-3.18.14.orig/fs/autofs4/expire.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/fs/autofs4/expire.c 2015-05-31 15:32:47.897635372 -0500 @@ -151,7 +151,7 @@ parent = p->d_parent; if (!spin_trylock(&parent->d_lock)) { spin_unlock(&p->d_lock); - cpu_relax(); + cpu_chill(); goto relock; } spin_unlock(&p->d_lock); diff -Nur linux-3.18.14.orig/fs/buffer.c linux-3.18.14-rt/fs/buffer.c --- linux-3.18.14.orig/fs/buffer.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/fs/buffer.c 2015-05-31 15:32:47.905635372 -0500 @@ -301,8 +301,7 @@ * decide that the page is now completely done. */ first = page_buffers(page); - local_irq_save(flags); - bit_spin_lock(BH_Uptodate_Lock, &first->b_state); + flags = bh_uptodate_lock_irqsave(first); clear_buffer_async_read(bh); unlock_buffer(bh); tmp = bh; @@ -315,8 +314,7 @@ } tmp = tmp->b_this_page; } while (tmp != bh); - bit_spin_unlock(BH_Uptodate_Lock, &first->b_state); - local_irq_restore(flags); + bh_uptodate_unlock_irqrestore(first, flags); /* * If none of the buffers had errors and they are all @@ -328,9 +326,7 @@ return; still_busy: - bit_spin_unlock(BH_Uptodate_Lock, &first->b_state); - local_irq_restore(flags); - return; + bh_uptodate_unlock_irqrestore(first, flags); } /* @@ -358,8 +354,7 @@ } first = page_buffers(page); - local_irq_save(flags); - bit_spin_lock(BH_Uptodate_Lock, &first->b_state); + flags = bh_uptodate_lock_irqsave(first); clear_buffer_async_write(bh); unlock_buffer(bh); @@ -371,15 +366,12 @@ } tmp = tmp->b_this_page; } - bit_spin_unlock(BH_Uptodate_Lock, &first->b_state); - local_irq_restore(flags); + bh_uptodate_unlock_irqrestore(first, flags); end_page_writeback(page); return; still_busy: - bit_spin_unlock(BH_Uptodate_Lock, &first->b_state); - local_irq_restore(flags); - return; + bh_uptodate_unlock_irqrestore(first, flags); } EXPORT_SYMBOL(end_buffer_async_write); @@ -3325,6 +3317,7 @@ struct buffer_head *ret = kmem_cache_zalloc(bh_cachep, gfp_flags); if (ret) { INIT_LIST_HEAD(&ret->b_assoc_buffers); + buffer_head_init_locks(ret); preempt_disable(); __this_cpu_inc(bh_accounting.nr); recalc_bh_state(); diff -Nur linux-3.18.14.orig/fs/dcache.c linux-3.18.14-rt/fs/dcache.c --- linux-3.18.14.orig/fs/dcache.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/fs/dcache.c 2015-05-31 15:32:47.929635371 -0500 @@ -19,6 +19,7 @@ #include #include #include +#include #include #include #include @@ -552,7 +553,7 @@ failed: spin_unlock(&dentry->d_lock); - cpu_relax(); + cpu_chill(); return dentry; /* try again with same dentry */ } @@ -2285,7 +2286,7 @@ if (dentry->d_lockref.count == 1) { if (!spin_trylock(&inode->i_lock)) { spin_unlock(&dentry->d_lock); - cpu_relax(); + cpu_chill(); goto again; } dentry->d_flags &= ~DCACHE_CANT_MOUNT; diff -Nur linux-3.18.14.orig/fs/eventpoll.c linux-3.18.14-rt/fs/eventpoll.c --- linux-3.18.14.orig/fs/eventpoll.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/fs/eventpoll.c 2015-05-31 15:32:47.945635371 -0500 @@ -505,12 +505,12 @@ */ static void ep_poll_safewake(wait_queue_head_t *wq) { - int this_cpu = get_cpu(); + int this_cpu = get_cpu_light(); ep_call_nested(&poll_safewake_ncalls, EP_MAX_NESTS, ep_poll_wakeup_proc, NULL, wq, (void *) (long) this_cpu); - put_cpu(); + put_cpu_light(); } static void ep_remove_wait_queue(struct eppoll_entry *pwq) diff -Nur linux-3.18.14.orig/fs/exec.c linux-3.18.14-rt/fs/exec.c --- linux-3.18.14.orig/fs/exec.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/fs/exec.c 2015-05-31 15:32:47.945635371 -0500 @@ -841,12 +841,14 @@ } } task_lock(tsk); + preempt_disable_rt(); active_mm = tsk->active_mm; tsk->mm = mm; tsk->active_mm = mm; activate_mm(active_mm, mm); tsk->mm->vmacache_seqnum = 0; vmacache_flush(tsk); + preempt_enable_rt(); task_unlock(tsk); if (old_mm) { up_read(&old_mm->mmap_sem); diff -Nur linux-3.18.14.orig/fs/jbd/checkpoint.c linux-3.18.14-rt/fs/jbd/checkpoint.c --- linux-3.18.14.orig/fs/jbd/checkpoint.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/fs/jbd/checkpoint.c 2015-05-31 15:32:47.957635371 -0500 @@ -129,6 +129,8 @@ if (journal->j_flags & JFS_ABORT) return; spin_unlock(&journal->j_state_lock); + if (current->plug) + io_schedule(); mutex_lock(&journal->j_checkpoint_mutex); /* diff -Nur linux-3.18.14.orig/fs/jbd2/checkpoint.c linux-3.18.14-rt/fs/jbd2/checkpoint.c --- linux-3.18.14.orig/fs/jbd2/checkpoint.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/fs/jbd2/checkpoint.c 2015-05-31 15:32:47.969635371 -0500 @@ -116,6 +116,8 @@ nblocks = jbd2_space_needed(journal); while (jbd2_log_space_left(journal) < nblocks) { write_unlock(&journal->j_state_lock); + if (current->plug) + io_schedule(); mutex_lock(&journal->j_checkpoint_mutex); /* diff -Nur linux-3.18.14.orig/fs/namespace.c linux-3.18.14-rt/fs/namespace.c --- linux-3.18.14.orig/fs/namespace.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/fs/namespace.c 2015-05-31 15:32:47.969635371 -0500 @@ -14,6 +14,7 @@ #include #include #include +#include #include #include #include /* init_rootfs */ @@ -344,8 +345,11 @@ * incremented count after it has set MNT_WRITE_HOLD. */ smp_mb(); - while (ACCESS_ONCE(mnt->mnt.mnt_flags) & MNT_WRITE_HOLD) - cpu_relax(); + while (ACCESS_ONCE(mnt->mnt.mnt_flags) & MNT_WRITE_HOLD) { + preempt_enable(); + cpu_chill(); + preempt_disable(); + } /* * After the slowpath clears MNT_WRITE_HOLD, mnt_is_readonly will * be set to match its requirements. So we must not load that until diff -Nur linux-3.18.14.orig/fs/ntfs/aops.c linux-3.18.14-rt/fs/ntfs/aops.c --- linux-3.18.14.orig/fs/ntfs/aops.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/fs/ntfs/aops.c 2015-05-31 15:32:47.969635371 -0500 @@ -107,8 +107,7 @@ "0x%llx.", (unsigned long long)bh->b_blocknr); } first = page_buffers(page); - local_irq_save(flags); - bit_spin_lock(BH_Uptodate_Lock, &first->b_state); + flags = bh_uptodate_lock_irqsave(first); clear_buffer_async_read(bh); unlock_buffer(bh); tmp = bh; @@ -123,8 +122,7 @@ } tmp = tmp->b_this_page; } while (tmp != bh); - bit_spin_unlock(BH_Uptodate_Lock, &first->b_state); - local_irq_restore(flags); + bh_uptodate_unlock_irqrestore(first, flags); /* * If none of the buffers had errors then we can set the page uptodate, * but we first have to perform the post read mst fixups, if the @@ -145,13 +143,13 @@ recs = PAGE_CACHE_SIZE / rec_size; /* Should have been verified before we got here... */ BUG_ON(!recs); - local_irq_save(flags); + local_irq_save_nort(flags); kaddr = kmap_atomic(page); for (i = 0; i < recs; i++) post_read_mst_fixup((NTFS_RECORD*)(kaddr + i * rec_size), rec_size); kunmap_atomic(kaddr); - local_irq_restore(flags); + local_irq_restore_nort(flags); flush_dcache_page(page); if (likely(page_uptodate && !PageError(page))) SetPageUptodate(page); @@ -159,9 +157,7 @@ unlock_page(page); return; still_busy: - bit_spin_unlock(BH_Uptodate_Lock, &first->b_state); - local_irq_restore(flags); - return; + bh_uptodate_unlock_irqrestore(first, flags); } /** diff -Nur linux-3.18.14.orig/fs/timerfd.c linux-3.18.14-rt/fs/timerfd.c --- linux-3.18.14.orig/fs/timerfd.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/fs/timerfd.c 2015-05-31 15:32:47.969635371 -0500 @@ -449,7 +449,10 @@ break; } spin_unlock_irq(&ctx->wqh.lock); - cpu_relax(); + if (isalarm(ctx)) + hrtimer_wait_for_timer(&ctx->t.alarm.timer); + else + hrtimer_wait_for_timer(&ctx->t.tmr); } /* diff -Nur linux-3.18.14.orig/fs/xfs/xfs_linux.h linux-3.18.14-rt/fs/xfs/xfs_linux.h --- linux-3.18.14.orig/fs/xfs/xfs_linux.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/fs/xfs/xfs_linux.h 2015-05-31 15:32:47.989635371 -0500 @@ -119,7 +119,7 @@ /* * Feature macros (disable/enable) */ -#ifdef CONFIG_SMP +#if defined(CONFIG_SMP) && !defined(CONFIG_PREEMPT_RT_FULL) #define HAVE_PERCPU_SB /* per cpu superblock counters are a 2.6 feature */ #else #undef HAVE_PERCPU_SB /* per cpu superblock counters are a 2.6 feature */ diff -Nur linux-3.18.14.orig/include/acpi/platform/aclinux.h linux-3.18.14-rt/include/acpi/platform/aclinux.h --- linux-3.18.14.orig/include/acpi/platform/aclinux.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/acpi/platform/aclinux.h 2015-05-31 15:32:48.013635371 -0500 @@ -123,6 +123,7 @@ #define acpi_cache_t struct kmem_cache #define acpi_spinlock spinlock_t * +#define acpi_raw_spinlock raw_spinlock_t * #define acpi_cpu_flags unsigned long /* Use native linux version of acpi_os_allocate_zeroed */ @@ -141,6 +142,20 @@ #define ACPI_USE_ALTERNATE_PROTOTYPE_acpi_os_get_thread_id #define ACPI_USE_ALTERNATE_PROTOTYPE_acpi_os_create_lock +#define acpi_os_create_raw_lock(__handle) \ +({ \ + raw_spinlock_t *lock = ACPI_ALLOCATE(sizeof(*lock)); \ + \ + if (lock) { \ + *(__handle) = lock; \ + raw_spin_lock_init(*(__handle)); \ + } \ + lock ? AE_OK : AE_NO_MEMORY; \ + }) + +#define acpi_os_delete_raw_lock(__handle) kfree(__handle) + + /* * OSL interfaces used by debugger/disassembler */ diff -Nur linux-3.18.14.orig/include/asm-generic/bug.h linux-3.18.14-rt/include/asm-generic/bug.h --- linux-3.18.14.orig/include/asm-generic/bug.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/asm-generic/bug.h 2015-05-31 15:32:48.037635370 -0500 @@ -206,6 +206,20 @@ # define WARN_ON_SMP(x) ({0;}) #endif +#ifdef CONFIG_PREEMPT_RT_BASE +# define BUG_ON_RT(c) BUG_ON(c) +# define BUG_ON_NONRT(c) do { } while (0) +# define WARN_ON_RT(condition) WARN_ON(condition) +# define WARN_ON_NONRT(condition) do { } while (0) +# define WARN_ON_ONCE_NONRT(condition) do { } while (0) +#else +# define BUG_ON_RT(c) do { } while (0) +# define BUG_ON_NONRT(c) BUG_ON(c) +# define WARN_ON_RT(condition) do { } while (0) +# define WARN_ON_NONRT(condition) WARN_ON(condition) +# define WARN_ON_ONCE_NONRT(condition) WARN_ON_ONCE(condition) +#endif + #endif /* __ASSEMBLY__ */ #endif diff -Nur linux-3.18.14.orig/include/linux/blkdev.h linux-3.18.14-rt/include/linux/blkdev.h --- linux-3.18.14.orig/include/linux/blkdev.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/blkdev.h 2015-05-31 15:32:48.077635370 -0500 @@ -101,6 +101,7 @@ struct list_head queuelist; union { struct call_single_data csd; + struct work_struct work; unsigned long fifo_time; }; @@ -478,7 +479,7 @@ struct throtl_data *td; #endif struct rcu_head rcu_head; - wait_queue_head_t mq_freeze_wq; + struct swait_head mq_freeze_wq; struct percpu_ref mq_usage_counter; struct list_head all_q_node; diff -Nur linux-3.18.14.orig/include/linux/blk-mq.h linux-3.18.14-rt/include/linux/blk-mq.h --- linux-3.18.14.orig/include/linux/blk-mq.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/blk-mq.h 2015-05-31 15:32:48.069635370 -0500 @@ -169,6 +169,7 @@ struct blk_mq_hw_ctx *blk_mq_map_queue(struct request_queue *, const int ctx_index); struct blk_mq_hw_ctx *blk_mq_alloc_single_hw_queue(struct blk_mq_tag_set *, unsigned int, int); +void __blk_mq_complete_request_remote_work(struct work_struct *work); void blk_mq_start_request(struct request *rq); void blk_mq_end_request(struct request *rq, int error); diff -Nur linux-3.18.14.orig/include/linux/bottom_half.h linux-3.18.14-rt/include/linux/bottom_half.h --- linux-3.18.14.orig/include/linux/bottom_half.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/bottom_half.h 2015-05-31 15:32:48.081635370 -0500 @@ -4,6 +4,17 @@ #include #include +#ifdef CONFIG_PREEMPT_RT_FULL + +extern void local_bh_disable(void); +extern void _local_bh_enable(void); +extern void local_bh_enable(void); +extern void local_bh_enable_ip(unsigned long ip); +extern void __local_bh_disable_ip(unsigned long ip, unsigned int cnt); +extern void __local_bh_enable_ip(unsigned long ip, unsigned int cnt); + +#else + #ifdef CONFIG_TRACE_IRQFLAGS extern void __local_bh_disable_ip(unsigned long ip, unsigned int cnt); #else @@ -31,5 +42,6 @@ { __local_bh_enable_ip(_THIS_IP_, SOFTIRQ_DISABLE_OFFSET); } +#endif #endif /* _LINUX_BH_H */ diff -Nur linux-3.18.14.orig/include/linux/buffer_head.h linux-3.18.14-rt/include/linux/buffer_head.h --- linux-3.18.14.orig/include/linux/buffer_head.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/buffer_head.h 2015-05-31 15:32:48.109635370 -0500 @@ -75,8 +75,52 @@ struct address_space *b_assoc_map; /* mapping this buffer is associated with */ atomic_t b_count; /* users using this buffer_head */ +#ifdef CONFIG_PREEMPT_RT_BASE + spinlock_t b_uptodate_lock; +#if defined(CONFIG_JBD) || defined(CONFIG_JBD_MODULE) || \ + defined(CONFIG_JBD2) || defined(CONFIG_JBD2_MODULE) + spinlock_t b_state_lock; + spinlock_t b_journal_head_lock; +#endif +#endif }; +static inline unsigned long bh_uptodate_lock_irqsave(struct buffer_head *bh) +{ + unsigned long flags; + +#ifndef CONFIG_PREEMPT_RT_BASE + local_irq_save(flags); + bit_spin_lock(BH_Uptodate_Lock, &bh->b_state); +#else + spin_lock_irqsave(&bh->b_uptodate_lock, flags); +#endif + return flags; +} + +static inline void +bh_uptodate_unlock_irqrestore(struct buffer_head *bh, unsigned long flags) +{ +#ifndef CONFIG_PREEMPT_RT_BASE + bit_spin_unlock(BH_Uptodate_Lock, &bh->b_state); + local_irq_restore(flags); +#else + spin_unlock_irqrestore(&bh->b_uptodate_lock, flags); +#endif +} + +static inline void buffer_head_init_locks(struct buffer_head *bh) +{ +#ifdef CONFIG_PREEMPT_RT_BASE + spin_lock_init(&bh->b_uptodate_lock); +#if defined(CONFIG_JBD) || defined(CONFIG_JBD_MODULE) || \ + defined(CONFIG_JBD2) || defined(CONFIG_JBD2_MODULE) + spin_lock_init(&bh->b_state_lock); + spin_lock_init(&bh->b_journal_head_lock); +#endif +#endif +} + /* * macro tricks to expand the set_buffer_foo(), clear_buffer_foo() * and buffer_foo() functions. diff -Nur linux-3.18.14.orig/include/linux/cgroup.h linux-3.18.14-rt/include/linux/cgroup.h --- linux-3.18.14.orig/include/linux/cgroup.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/cgroup.h 2015-05-31 15:32:48.117635370 -0500 @@ -22,6 +22,7 @@ #include #include #include +#include #ifdef CONFIG_CGROUPS @@ -91,6 +92,7 @@ /* percpu_ref killing and RCU release */ struct rcu_head rcu_head; struct work_struct destroy_work; + struct swork_event destroy_swork; }; /* bits in struct cgroup_subsys_state flags field */ diff -Nur linux-3.18.14.orig/include/linux/completion.h linux-3.18.14-rt/include/linux/completion.h --- linux-3.18.14.orig/include/linux/completion.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/completion.h 2015-05-31 15:32:48.117635370 -0500 @@ -7,8 +7,7 @@ * Atomic wait-for-completion handler data structures. * See kernel/sched/completion.c for details. */ - -#include +#include /* * struct completion - structure used to maintain state for a "completion" @@ -24,11 +23,11 @@ */ struct completion { unsigned int done; - wait_queue_head_t wait; + struct swait_head wait; }; #define COMPLETION_INITIALIZER(work) \ - { 0, __WAIT_QUEUE_HEAD_INITIALIZER((work).wait) } + { 0, SWAIT_HEAD_INITIALIZER((work).wait) } #define COMPLETION_INITIALIZER_ONSTACK(work) \ ({ init_completion(&work); work; }) @@ -73,7 +72,7 @@ static inline void init_completion(struct completion *x) { x->done = 0; - init_waitqueue_head(&x->wait); + init_swait_head(&x->wait); } /** diff -Nur linux-3.18.14.orig/include/linux/cpu.h linux-3.18.14-rt/include/linux/cpu.h --- linux-3.18.14.orig/include/linux/cpu.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/cpu.h 2015-05-31 15:32:48.129635370 -0500 @@ -217,6 +217,8 @@ extern void put_online_cpus(void); extern void cpu_hotplug_disable(void); extern void cpu_hotplug_enable(void); +extern void pin_current_cpu(void); +extern void unpin_current_cpu(void); #define hotcpu_notifier(fn, pri) cpu_notifier(fn, pri) #define __hotcpu_notifier(fn, pri) __cpu_notifier(fn, pri) #define register_hotcpu_notifier(nb) register_cpu_notifier(nb) @@ -235,6 +237,8 @@ #define put_online_cpus() do { } while (0) #define cpu_hotplug_disable() do { } while (0) #define cpu_hotplug_enable() do { } while (0) +static inline void pin_current_cpu(void) { } +static inline void unpin_current_cpu(void) { } #define hotcpu_notifier(fn, pri) do { (void)(fn); } while (0) #define __hotcpu_notifier(fn, pri) do { (void)(fn); } while (0) /* These aren't inline functions due to a GCC bug. */ diff -Nur linux-3.18.14.orig/include/linux/delay.h linux-3.18.14-rt/include/linux/delay.h --- linux-3.18.14.orig/include/linux/delay.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/delay.h 2015-05-31 15:32:48.129635370 -0500 @@ -52,4 +52,10 @@ msleep(seconds * 1000); } +#ifdef CONFIG_PREEMPT_RT_FULL +extern void cpu_chill(void); +#else +# define cpu_chill() cpu_relax() +#endif + #endif /* defined(_LINUX_DELAY_H) */ diff -Nur linux-3.18.14.orig/include/linux/ftrace_event.h linux-3.18.14-rt/include/linux/ftrace_event.h --- linux-3.18.14.orig/include/linux/ftrace_event.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/ftrace_event.h 2015-05-31 15:32:48.157635370 -0500 @@ -61,6 +61,9 @@ unsigned char flags; unsigned char preempt_count; int pid; + unsigned short migrate_disable; + unsigned short padding; + unsigned char preempt_lazy_count; }; #define FTRACE_MAX_EVENT \ diff -Nur linux-3.18.14.orig/include/linux/highmem.h linux-3.18.14-rt/include/linux/highmem.h --- linux-3.18.14.orig/include/linux/highmem.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/highmem.h 2015-05-31 15:32:48.157635370 -0500 @@ -7,6 +7,7 @@ #include #include #include +#include #include @@ -85,32 +86,51 @@ #if defined(CONFIG_HIGHMEM) || defined(CONFIG_X86_32) +#ifndef CONFIG_PREEMPT_RT_FULL DECLARE_PER_CPU(int, __kmap_atomic_idx); +#endif static inline int kmap_atomic_idx_push(void) { +#ifndef CONFIG_PREEMPT_RT_FULL int idx = __this_cpu_inc_return(__kmap_atomic_idx) - 1; -#ifdef CONFIG_DEBUG_HIGHMEM +# ifdef CONFIG_DEBUG_HIGHMEM WARN_ON_ONCE(in_irq() && !irqs_disabled()); BUG_ON(idx >= KM_TYPE_NR); -#endif +# endif return idx; +#else + current->kmap_idx++; + BUG_ON(current->kmap_idx > KM_TYPE_NR); + return current->kmap_idx - 1; +#endif } static inline int kmap_atomic_idx(void) { +#ifndef CONFIG_PREEMPT_RT_FULL return __this_cpu_read(__kmap_atomic_idx) - 1; +#else + return current->kmap_idx - 1; +#endif } static inline void kmap_atomic_idx_pop(void) { -#ifdef CONFIG_DEBUG_HIGHMEM +#ifndef CONFIG_PREEMPT_RT_FULL +# ifdef CONFIG_DEBUG_HIGHMEM int idx = __this_cpu_dec_return(__kmap_atomic_idx); BUG_ON(idx < 0); -#else +# else __this_cpu_dec(__kmap_atomic_idx); +# endif +#else + current->kmap_idx--; +# ifdef CONFIG_DEBUG_HIGHMEM + BUG_ON(current->kmap_idx < 0); +# endif #endif } diff -Nur linux-3.18.14.orig/include/linux/hrtimer.h linux-3.18.14-rt/include/linux/hrtimer.h --- linux-3.18.14.orig/include/linux/hrtimer.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/hrtimer.h 2015-05-31 15:32:48.161635369 -0500 @@ -111,6 +111,11 @@ enum hrtimer_restart (*function)(struct hrtimer *); struct hrtimer_clock_base *base; unsigned long state; + struct list_head cb_entry; + int irqsafe; +#ifdef CONFIG_MISSED_TIMER_OFFSETS_HIST + ktime_t praecox; +#endif #ifdef CONFIG_TIMER_STATS int start_pid; void *start_site; @@ -147,6 +152,7 @@ int index; clockid_t clockid; struct timerqueue_head active; + struct list_head expired; ktime_t resolution; ktime_t (*get_time)(void); ktime_t softirq_time; @@ -192,6 +198,9 @@ unsigned long nr_hangs; ktime_t max_hang_time; #endif +#ifdef CONFIG_PREEMPT_RT_BASE + wait_queue_head_t wait; +#endif struct hrtimer_clock_base clock_base[HRTIMER_MAX_CLOCK_BASES]; }; @@ -379,6 +388,13 @@ return hrtimer_start_expires(timer, HRTIMER_MODE_ABS); } +/* Softirq preemption could deadlock timer removal */ +#ifdef CONFIG_PREEMPT_RT_BASE + extern void hrtimer_wait_for_timer(const struct hrtimer *timer); +#else +# define hrtimer_wait_for_timer(timer) do { cpu_relax(); } while (0) +#endif + /* Query timers: */ extern ktime_t hrtimer_get_remaining(const struct hrtimer *timer); extern int hrtimer_get_res(const clockid_t which_clock, struct timespec *tp); diff -Nur linux-3.18.14.orig/include/linux/idr.h linux-3.18.14-rt/include/linux/idr.h --- linux-3.18.14.orig/include/linux/idr.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/idr.h 2015-05-31 15:32:48.161635369 -0500 @@ -95,10 +95,14 @@ * Each idr_preload() should be matched with an invocation of this * function. See idr_preload() for details. */ +#ifdef CONFIG_PREEMPT_RT_FULL +void idr_preload_end(void); +#else static inline void idr_preload_end(void) { preempt_enable(); } +#endif /** * idr_find - return pointer for given id diff -Nur linux-3.18.14.orig/include/linux/init_task.h linux-3.18.14-rt/include/linux/init_task.h --- linux-3.18.14.orig/include/linux/init_task.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/init_task.h 2015-05-31 15:32:48.177635369 -0500 @@ -147,9 +147,16 @@ # define INIT_PERF_EVENTS(tsk) #endif +#ifdef CONFIG_PREEMPT_RT_BASE +# define INIT_TIMER_LIST .posix_timer_list = NULL, +#else +# define INIT_TIMER_LIST +#endif + #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN # define INIT_VTIME(tsk) \ - .vtime_seqlock = __SEQLOCK_UNLOCKED(tsk.vtime_seqlock), \ + .vtime_lock = __RAW_SPIN_LOCK_UNLOCKED(tsk.vtime_lock), \ + .vtime_seq = SEQCNT_ZERO(tsk.vtime_seq), \ .vtime_snap = 0, \ .vtime_snap_whence = VTIME_SYS, #else @@ -219,6 +226,7 @@ .cpu_timers = INIT_CPU_TIMERS(tsk.cpu_timers), \ .pi_lock = __RAW_SPIN_LOCK_UNLOCKED(tsk.pi_lock), \ .timer_slack_ns = 50000, /* 50 usec default slack */ \ + INIT_TIMER_LIST \ .pids = { \ [PIDTYPE_PID] = INIT_PID_LINK(PIDTYPE_PID), \ [PIDTYPE_PGID] = INIT_PID_LINK(PIDTYPE_PGID), \ diff -Nur linux-3.18.14.orig/include/linux/interrupt.h linux-3.18.14-rt/include/linux/interrupt.h --- linux-3.18.14.orig/include/linux/interrupt.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/interrupt.h 2015-05-31 15:32:48.181635369 -0500 @@ -57,6 +57,7 @@ * IRQF_NO_THREAD - Interrupt cannot be threaded * IRQF_EARLY_RESUME - Resume IRQ early during syscore instead of at device * resume time. + * IRQF_NO_SOFTIRQ_CALL - Do not process softirqs in the irq thread context (RT) */ #define IRQF_DISABLED 0x00000020 #define IRQF_SHARED 0x00000080 @@ -70,6 +71,7 @@ #define IRQF_FORCE_RESUME 0x00008000 #define IRQF_NO_THREAD 0x00010000 #define IRQF_EARLY_RESUME 0x00020000 +#define IRQF_NO_SOFTIRQ_CALL 0x00080000 #define IRQF_TIMER (__IRQF_TIMER | IRQF_NO_SUSPEND | IRQF_NO_THREAD) @@ -180,7 +182,7 @@ #ifdef CONFIG_LOCKDEP # define local_irq_enable_in_hardirq() do { } while (0) #else -# define local_irq_enable_in_hardirq() local_irq_enable() +# define local_irq_enable_in_hardirq() local_irq_enable_nort() #endif extern void disable_irq_nosync(unsigned int irq); @@ -210,6 +212,7 @@ unsigned int irq; struct kref kref; struct work_struct work; + struct list_head list; void (*notify)(struct irq_affinity_notify *, const cpumask_t *mask); void (*release)(struct kref *ref); }; @@ -358,9 +361,13 @@ #ifdef CONFIG_IRQ_FORCED_THREADING +# ifndef CONFIG_PREEMPT_RT_BASE extern bool force_irqthreads; +# else +# define force_irqthreads (true) +# endif #else -#define force_irqthreads (0) +#define force_irqthreads (false) #endif #ifndef __ARCH_SET_SOFTIRQ_PENDING @@ -416,9 +423,10 @@ void (*action)(struct softirq_action *); }; +#ifndef CONFIG_PREEMPT_RT_FULL asmlinkage void do_softirq(void); asmlinkage void __do_softirq(void); - +static inline void thread_do_softirq(void) { do_softirq(); } #ifdef __ARCH_HAS_DO_SOFTIRQ void do_softirq_own_stack(void); #else @@ -427,6 +435,9 @@ __do_softirq(); } #endif +#else +extern void thread_do_softirq(void); +#endif extern void open_softirq(int nr, void (*action)(struct softirq_action *)); extern void softirq_init(void); @@ -434,6 +445,7 @@ extern void raise_softirq_irqoff(unsigned int nr); extern void raise_softirq(unsigned int nr); +extern void softirq_check_pending_idle(void); DECLARE_PER_CPU(struct task_struct *, ksoftirqd); @@ -455,8 +467,9 @@ to be executed on some cpu at least once after this. * If the tasklet is already scheduled, but its execution is still not started, it will be executed only once. - * If this tasklet is already running on another CPU (or schedule is called - from tasklet itself), it is rescheduled for later. + * If this tasklet is already running on another CPU, it is rescheduled + for later. + * Schedule must not be called from the tasklet itself (a lockup occurs) * Tasklet is strictly serialized wrt itself, but not wrt another tasklets. If client needs some intertask synchronization, he makes it with spinlocks. @@ -481,27 +494,36 @@ enum { TASKLET_STATE_SCHED, /* Tasklet is scheduled for execution */ - TASKLET_STATE_RUN /* Tasklet is running (SMP only) */ + TASKLET_STATE_RUN, /* Tasklet is running (SMP only) */ + TASKLET_STATE_PENDING /* Tasklet is pending */ }; -#ifdef CONFIG_SMP +#define TASKLET_STATEF_SCHED (1 << TASKLET_STATE_SCHED) +#define TASKLET_STATEF_RUN (1 << TASKLET_STATE_RUN) +#define TASKLET_STATEF_PENDING (1 << TASKLET_STATE_PENDING) + +#if defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT_FULL) static inline int tasklet_trylock(struct tasklet_struct *t) { return !test_and_set_bit(TASKLET_STATE_RUN, &(t)->state); } +static inline int tasklet_tryunlock(struct tasklet_struct *t) +{ + return cmpxchg(&t->state, TASKLET_STATEF_RUN, 0) == TASKLET_STATEF_RUN; +} + static inline void tasklet_unlock(struct tasklet_struct *t) { smp_mb__before_atomic(); clear_bit(TASKLET_STATE_RUN, &(t)->state); } -static inline void tasklet_unlock_wait(struct tasklet_struct *t) -{ - while (test_bit(TASKLET_STATE_RUN, &(t)->state)) { barrier(); } -} +extern void tasklet_unlock_wait(struct tasklet_struct *t); + #else #define tasklet_trylock(t) 1 +#define tasklet_tryunlock(t) 1 #define tasklet_unlock_wait(t) do { } while (0) #define tasklet_unlock(t) do { } while (0) #endif @@ -550,17 +572,8 @@ smp_mb(); } -static inline void tasklet_enable(struct tasklet_struct *t) -{ - smp_mb__before_atomic(); - atomic_dec(&t->count); -} - -static inline void tasklet_hi_enable(struct tasklet_struct *t) -{ - smp_mb__before_atomic(); - atomic_dec(&t->count); -} +extern void tasklet_enable(struct tasklet_struct *t); +extern void tasklet_hi_enable(struct tasklet_struct *t); extern void tasklet_kill(struct tasklet_struct *t); extern void tasklet_kill_immediate(struct tasklet_struct *t, unsigned int cpu); @@ -592,6 +605,12 @@ tasklet_kill(&ttimer->tasklet); } +#ifdef CONFIG_PREEMPT_RT_FULL +extern void softirq_early_init(void); +#else +static inline void softirq_early_init(void) { } +#endif + /* * Autoprobing for irqs: * diff -Nur linux-3.18.14.orig/include/linux/irqdesc.h linux-3.18.14-rt/include/linux/irqdesc.h --- linux-3.18.14.orig/include/linux/irqdesc.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/irqdesc.h 2015-05-31 15:32:48.217635369 -0500 @@ -63,6 +63,7 @@ unsigned int irqs_unhandled; atomic_t threads_handled; int threads_handled_last; + u64 random_ip; raw_spinlock_t lock; struct cpumask *percpu_enabled; #ifdef CONFIG_SMP diff -Nur linux-3.18.14.orig/include/linux/irqflags.h linux-3.18.14-rt/include/linux/irqflags.h --- linux-3.18.14.orig/include/linux/irqflags.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/irqflags.h 2015-05-31 15:32:48.233635369 -0500 @@ -25,8 +25,6 @@ # define trace_softirqs_enabled(p) ((p)->softirqs_enabled) # define trace_hardirq_enter() do { current->hardirq_context++; } while (0) # define trace_hardirq_exit() do { current->hardirq_context--; } while (0) -# define lockdep_softirq_enter() do { current->softirq_context++; } while (0) -# define lockdep_softirq_exit() do { current->softirq_context--; } while (0) # define INIT_TRACE_IRQFLAGS .softirqs_enabled = 1, #else # define trace_hardirqs_on() do { } while (0) @@ -39,9 +37,15 @@ # define trace_softirqs_enabled(p) 0 # define trace_hardirq_enter() do { } while (0) # define trace_hardirq_exit() do { } while (0) +# define INIT_TRACE_IRQFLAGS +#endif + +#if defined(CONFIG_TRACE_IRQFLAGS) && !defined(CONFIG_PREEMPT_RT_FULL) +# define lockdep_softirq_enter() do { current->softirq_context++; } while (0) +# define lockdep_softirq_exit() do { current->softirq_context--; } while (0) +#else # define lockdep_softirq_enter() do { } while (0) # define lockdep_softirq_exit() do { } while (0) -# define INIT_TRACE_IRQFLAGS #endif #if defined(CONFIG_IRQSOFF_TRACER) || \ @@ -147,4 +151,23 @@ #endif /* CONFIG_TRACE_IRQFLAGS_SUPPORT */ +/* + * local_irq* variants depending on RT/!RT + */ +#ifdef CONFIG_PREEMPT_RT_FULL +# define local_irq_disable_nort() do { } while (0) +# define local_irq_enable_nort() do { } while (0) +# define local_irq_save_nort(flags) local_save_flags(flags) +# define local_irq_restore_nort(flags) (void)(flags) +# define local_irq_disable_rt() local_irq_disable() +# define local_irq_enable_rt() local_irq_enable() +#else +# define local_irq_disable_nort() local_irq_disable() +# define local_irq_enable_nort() local_irq_enable() +# define local_irq_save_nort(flags) local_irq_save(flags) +# define local_irq_restore_nort(flags) local_irq_restore(flags) +# define local_irq_disable_rt() do { } while (0) +# define local_irq_enable_rt() do { } while (0) +#endif + #endif diff -Nur linux-3.18.14.orig/include/linux/irq.h linux-3.18.14-rt/include/linux/irq.h --- linux-3.18.14.orig/include/linux/irq.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/irq.h 2015-05-31 15:32:48.185635369 -0500 @@ -73,6 +73,7 @@ * IRQ_IS_POLLED - Always polled by another interrupt. Exclude * it from the spurious interrupt detection * mechanism and from core side polling. + * IRQ_NO_SOFTIRQ_CALL - No softirq processing in the irq thread context (RT) */ enum { IRQ_TYPE_NONE = 0x00000000, @@ -98,13 +99,14 @@ IRQ_NOTHREAD = (1 << 16), IRQ_PER_CPU_DEVID = (1 << 17), IRQ_IS_POLLED = (1 << 18), + IRQ_NO_SOFTIRQ_CALL = (1 << 19), }; #define IRQF_MODIFY_MASK \ (IRQ_TYPE_SENSE_MASK | IRQ_NOPROBE | IRQ_NOREQUEST | \ IRQ_NOAUTOEN | IRQ_MOVE_PCNTXT | IRQ_LEVEL | IRQ_NO_BALANCING | \ IRQ_PER_CPU | IRQ_NESTED_THREAD | IRQ_NOTHREAD | IRQ_PER_CPU_DEVID | \ - IRQ_IS_POLLED) + IRQ_IS_POLLED | IRQ_NO_SOFTIRQ_CALL) #define IRQ_NO_BALANCING_MASK (IRQ_PER_CPU | IRQ_NO_BALANCING) diff -Nur linux-3.18.14.orig/include/linux/irq_work.h linux-3.18.14-rt/include/linux/irq_work.h --- linux-3.18.14.orig/include/linux/irq_work.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/irq_work.h 2015-05-31 15:32:48.217635369 -0500 @@ -16,6 +16,7 @@ #define IRQ_WORK_BUSY 2UL #define IRQ_WORK_FLAGS 3UL #define IRQ_WORK_LAZY 4UL /* Doesn't want IPI, wait for tick */ +#define IRQ_WORK_HARD_IRQ 8UL /* Run hard IRQ context, even on RT */ struct irq_work { unsigned long flags; diff -Nur linux-3.18.14.orig/include/linux/jbd_common.h linux-3.18.14-rt/include/linux/jbd_common.h --- linux-3.18.14.orig/include/linux/jbd_common.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/jbd_common.h 2015-05-31 15:32:48.237635369 -0500 @@ -15,32 +15,56 @@ static inline void jbd_lock_bh_state(struct buffer_head *bh) { +#ifndef CONFIG_PREEMPT_RT_BASE bit_spin_lock(BH_State, &bh->b_state); +#else + spin_lock(&bh->b_state_lock); +#endif } static inline int jbd_trylock_bh_state(struct buffer_head *bh) { +#ifndef CONFIG_PREEMPT_RT_BASE return bit_spin_trylock(BH_State, &bh->b_state); +#else + return spin_trylock(&bh->b_state_lock); +#endif } static inline int jbd_is_locked_bh_state(struct buffer_head *bh) { +#ifndef CONFIG_PREEMPT_RT_BASE return bit_spin_is_locked(BH_State, &bh->b_state); +#else + return spin_is_locked(&bh->b_state_lock); +#endif } static inline void jbd_unlock_bh_state(struct buffer_head *bh) { +#ifndef CONFIG_PREEMPT_RT_BASE bit_spin_unlock(BH_State, &bh->b_state); +#else + spin_unlock(&bh->b_state_lock); +#endif } static inline void jbd_lock_bh_journal_head(struct buffer_head *bh) { +#ifndef CONFIG_PREEMPT_RT_BASE bit_spin_lock(BH_JournalHead, &bh->b_state); +#else + spin_lock(&bh->b_journal_head_lock); +#endif } static inline void jbd_unlock_bh_journal_head(struct buffer_head *bh) { +#ifndef CONFIG_PREEMPT_RT_BASE bit_spin_unlock(BH_JournalHead, &bh->b_state); +#else + spin_unlock(&bh->b_journal_head_lock); +#endif } #endif diff -Nur linux-3.18.14.orig/include/linux/jump_label.h linux-3.18.14-rt/include/linux/jump_label.h --- linux-3.18.14.orig/include/linux/jump_label.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/jump_label.h 2015-05-31 15:32:48.237635369 -0500 @@ -55,7 +55,8 @@ "%s used before call to jump_label_init", \ __func__) -#if defined(CC_HAVE_ASM_GOTO) && defined(CONFIG_JUMP_LABEL) +#if defined(CC_HAVE_ASM_GOTO) && defined(CONFIG_JUMP_LABEL) && \ + !defined(CONFIG_PREEMPT_BASE) struct static_key { atomic_t enabled; diff -Nur linux-3.18.14.orig/include/linux/kdb.h linux-3.18.14-rt/include/linux/kdb.h --- linux-3.18.14.orig/include/linux/kdb.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/kdb.h 2015-05-31 15:32:48.245635369 -0500 @@ -116,7 +116,7 @@ extern __printf(1, 0) int vkdb_printf(const char *fmt, va_list args); extern __printf(1, 2) int kdb_printf(const char *, ...); typedef __printf(1, 2) int (*kdb_printf_t)(const char *, ...); - +#define in_kdb_printk() (kdb_trap_printk) extern void kdb_init(int level); /* Access to kdb specific polling devices */ @@ -151,6 +151,7 @@ extern int kdb_unregister(char *); #else /* ! CONFIG_KGDB_KDB */ static inline __printf(1, 2) int kdb_printf(const char *fmt, ...) { return 0; } +#define in_kdb_printk() (0) static inline void kdb_init(int level) {} static inline int kdb_register(char *cmd, kdb_func_t func, char *usage, char *help, short minlen) { return 0; } diff -Nur linux-3.18.14.orig/include/linux/kernel.h linux-3.18.14-rt/include/linux/kernel.h --- linux-3.18.14.orig/include/linux/kernel.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/kernel.h 2015-05-31 15:32:48.245635369 -0500 @@ -451,6 +451,7 @@ SYSTEM_HALT, SYSTEM_POWER_OFF, SYSTEM_RESTART, + SYSTEM_SUSPEND, } system_state; #define TAINT_PROPRIETARY_MODULE 0 diff -Nur linux-3.18.14.orig/include/linux/kvm_host.h linux-3.18.14-rt/include/linux/kvm_host.h --- linux-3.18.14.orig/include/linux/kvm_host.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/kvm_host.h 2015-05-31 15:32:48.253635368 -0500 @@ -245,7 +245,7 @@ int fpu_active; int guest_fpu_loaded, guest_xcr0_loaded; - wait_queue_head_t wq; + struct swait_head wq; struct pid *pid; int sigset_active; sigset_t sigset; @@ -688,7 +688,7 @@ } #endif -static inline wait_queue_head_t *kvm_arch_vcpu_wq(struct kvm_vcpu *vcpu) +static inline struct swait_head *kvm_arch_vcpu_wq(struct kvm_vcpu *vcpu) { #ifdef __KVM_HAVE_ARCH_WQP return vcpu->arch.wqp; diff -Nur linux-3.18.14.orig/include/linux/kvm_host.h.orig linux-3.18.14-rt/include/linux/kvm_host.h.orig --- linux-3.18.14.orig/include/linux/kvm_host.h.orig 1969-12-31 18:00:00.000000000 -0600 +++ linux-3.18.14-rt/include/linux/kvm_host.h.orig 2015-05-20 10:04:50.000000000 -0500 @@ -0,0 +1,1111 @@ +#ifndef __KVM_HOST_H +#define __KVM_HOST_H + +/* + * This work is licensed under the terms of the GNU GPL, version 2. See + * the COPYING file in the top-level directory. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include + +#include + +#include + +#ifndef KVM_MMIO_SIZE +#define KVM_MMIO_SIZE 8 +#endif + +/* + * The bit 16 ~ bit 31 of kvm_memory_region::flags are internally used + * in kvm, other bits are visible for userspace which are defined in + * include/linux/kvm_h. + */ +#define KVM_MEMSLOT_INVALID (1UL << 16) +#define KVM_MEMSLOT_INCOHERENT (1UL << 17) + +/* Two fragments for cross MMIO pages. */ +#define KVM_MAX_MMIO_FRAGMENTS 2 + +/* + * For the normal pfn, the highest 12 bits should be zero, + * so we can mask bit 62 ~ bit 52 to indicate the error pfn, + * mask bit 63 to indicate the noslot pfn. + */ +#define KVM_PFN_ERR_MASK (0x7ffULL << 52) +#define KVM_PFN_ERR_NOSLOT_MASK (0xfffULL << 52) +#define KVM_PFN_NOSLOT (0x1ULL << 63) + +#define KVM_PFN_ERR_FAULT (KVM_PFN_ERR_MASK) +#define KVM_PFN_ERR_HWPOISON (KVM_PFN_ERR_MASK + 1) +#define KVM_PFN_ERR_RO_FAULT (KVM_PFN_ERR_MASK + 2) + +/* + * error pfns indicate that the gfn is in slot but faild to + * translate it to pfn on host. + */ +static inline bool is_error_pfn(pfn_t pfn) +{ + return !!(pfn & KVM_PFN_ERR_MASK); +} + +/* + * error_noslot pfns indicate that the gfn can not be + * translated to pfn - it is not in slot or failed to + * translate it to pfn. + */ +static inline bool is_error_noslot_pfn(pfn_t pfn) +{ + return !!(pfn & KVM_PFN_ERR_NOSLOT_MASK); +} + +/* noslot pfn indicates that the gfn is not in slot. */ +static inline bool is_noslot_pfn(pfn_t pfn) +{ + return pfn == KVM_PFN_NOSLOT; +} + +/* + * architectures with KVM_HVA_ERR_BAD other than PAGE_OFFSET (e.g. s390) + * provide own defines and kvm_is_error_hva + */ +#ifndef KVM_HVA_ERR_BAD + +#define KVM_HVA_ERR_BAD (PAGE_OFFSET) +#define KVM_HVA_ERR_RO_BAD (PAGE_OFFSET + PAGE_SIZE) + +static inline bool kvm_is_error_hva(unsigned long addr) +{ + return addr >= PAGE_OFFSET; +} + +#endif + +#define KVM_ERR_PTR_BAD_PAGE (ERR_PTR(-ENOENT)) + +static inline bool is_error_page(struct page *page) +{ + return IS_ERR(page); +} + +/* + * vcpu->requests bit members + */ +#define KVM_REQ_TLB_FLUSH 0 +#define KVM_REQ_MIGRATE_TIMER 1 +#define KVM_REQ_REPORT_TPR_ACCESS 2 +#define KVM_REQ_MMU_RELOAD 3 +#define KVM_REQ_TRIPLE_FAULT 4 +#define KVM_REQ_PENDING_TIMER 5 +#define KVM_REQ_UNHALT 6 +#define KVM_REQ_MMU_SYNC 7 +#define KVM_REQ_CLOCK_UPDATE 8 +#define KVM_REQ_KICK 9 +#define KVM_REQ_DEACTIVATE_FPU 10 +#define KVM_REQ_EVENT 11 +#define KVM_REQ_APF_HALT 12 +#define KVM_REQ_STEAL_UPDATE 13 +#define KVM_REQ_NMI 14 +#define KVM_REQ_PMU 15 +#define KVM_REQ_PMI 16 +#define KVM_REQ_WATCHDOG 17 +#define KVM_REQ_MASTERCLOCK_UPDATE 18 +#define KVM_REQ_MCLOCK_INPROGRESS 19 +#define KVM_REQ_EPR_EXIT 20 +#define KVM_REQ_SCAN_IOAPIC 21 +#define KVM_REQ_GLOBAL_CLOCK_UPDATE 22 +#define KVM_REQ_ENABLE_IBS 23 +#define KVM_REQ_DISABLE_IBS 24 +#define KVM_REQ_APIC_PAGE_RELOAD 25 + +#define KVM_USERSPACE_IRQ_SOURCE_ID 0 +#define KVM_IRQFD_RESAMPLE_IRQ_SOURCE_ID 1 + +extern struct kmem_cache *kvm_vcpu_cache; + +extern spinlock_t kvm_lock; +extern struct list_head vm_list; + +struct kvm_io_range { + gpa_t addr; + int len; + struct kvm_io_device *dev; +}; + +#define NR_IOBUS_DEVS 1000 + +struct kvm_io_bus { + int dev_count; + int ioeventfd_count; + struct kvm_io_range range[]; +}; + +enum kvm_bus { + KVM_MMIO_BUS, + KVM_PIO_BUS, + KVM_VIRTIO_CCW_NOTIFY_BUS, + KVM_FAST_MMIO_BUS, + KVM_NR_BUSES +}; + +int kvm_io_bus_write(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr, + int len, const void *val); +int kvm_io_bus_write_cookie(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr, + int len, const void *val, long cookie); +int kvm_io_bus_read(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr, int len, + void *val); +int kvm_io_bus_register_dev(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr, + int len, struct kvm_io_device *dev); +int kvm_io_bus_unregister_dev(struct kvm *kvm, enum kvm_bus bus_idx, + struct kvm_io_device *dev); + +#ifdef CONFIG_KVM_ASYNC_PF +struct kvm_async_pf { + struct work_struct work; + struct list_head link; + struct list_head queue; + struct kvm_vcpu *vcpu; + struct mm_struct *mm; + gva_t gva; + unsigned long addr; + struct kvm_arch_async_pf arch; + bool wakeup_all; +}; + +void kvm_clear_async_pf_completion_queue(struct kvm_vcpu *vcpu); +void kvm_check_async_pf_completion(struct kvm_vcpu *vcpu); +int kvm_setup_async_pf(struct kvm_vcpu *vcpu, gva_t gva, unsigned long hva, + struct kvm_arch_async_pf *arch); +int kvm_async_pf_wakeup_all(struct kvm_vcpu *vcpu); +#endif + +/* + * Carry out a gup that requires IO. Allow the mm to relinquish the mmap + * semaphore if the filemap/swap has to wait on a page lock. pagep == NULL + * controls whether we retry the gup one more time to completion in that case. + * Typically this is called after a FAULT_FLAG_RETRY_NOWAIT in the main tdp + * handler. + */ +int kvm_get_user_page_io(struct task_struct *tsk, struct mm_struct *mm, + unsigned long addr, bool write_fault, + struct page **pagep); + +enum { + OUTSIDE_GUEST_MODE, + IN_GUEST_MODE, + EXITING_GUEST_MODE, + READING_SHADOW_PAGE_TABLES, +}; + +/* + * Sometimes a large or cross-page mmio needs to be broken up into separate + * exits for userspace servicing. + */ +struct kvm_mmio_fragment { + gpa_t gpa; + void *data; + unsigned len; +}; + +struct kvm_vcpu { + struct kvm *kvm; +#ifdef CONFIG_PREEMPT_NOTIFIERS + struct preempt_notifier preempt_notifier; +#endif + int cpu; + int vcpu_id; + int srcu_idx; + int mode; + unsigned long requests; + unsigned long guest_debug; + + struct mutex mutex; + struct kvm_run *run; + + int fpu_active; + int guest_fpu_loaded, guest_xcr0_loaded; + wait_queue_head_t wq; + struct pid *pid; + int sigset_active; + sigset_t sigset; + struct kvm_vcpu_stat stat; + +#ifdef CONFIG_HAS_IOMEM + int mmio_needed; + int mmio_read_completed; + int mmio_is_write; + int mmio_cur_fragment; + int mmio_nr_fragments; + struct kvm_mmio_fragment mmio_fragments[KVM_MAX_MMIO_FRAGMENTS]; +#endif + +#ifdef CONFIG_KVM_ASYNC_PF + struct { + u32 queued; + struct list_head queue; + struct list_head done; + spinlock_t lock; + } async_pf; +#endif + +#ifdef CONFIG_HAVE_KVM_CPU_RELAX_INTERCEPT + /* + * Cpu relax intercept or pause loop exit optimization + * in_spin_loop: set when a vcpu does a pause loop exit + * or cpu relax intercepted. + * dy_eligible: indicates whether vcpu is eligible for directed yield. + */ + struct { + bool in_spin_loop; + bool dy_eligible; + } spin_loop; +#endif + bool preempted; + struct kvm_vcpu_arch arch; +}; + +static inline int kvm_vcpu_exiting_guest_mode(struct kvm_vcpu *vcpu) +{ + return cmpxchg(&vcpu->mode, IN_GUEST_MODE, EXITING_GUEST_MODE); +} + +/* + * Some of the bitops functions do not support too long bitmaps. + * This number must be determined not to exceed such limits. + */ +#define KVM_MEM_MAX_NR_PAGES ((1UL << 31) - 1) + +struct kvm_memory_slot { + gfn_t base_gfn; + unsigned long npages; + unsigned long *dirty_bitmap; + struct kvm_arch_memory_slot arch; + unsigned long userspace_addr; + u32 flags; + short id; +}; + +static inline unsigned long kvm_dirty_bitmap_bytes(struct kvm_memory_slot *memslot) +{ + return ALIGN(memslot->npages, BITS_PER_LONG) / 8; +} + +struct kvm_s390_adapter_int { + u64 ind_addr; + u64 summary_addr; + u64 ind_offset; + u32 summary_offset; + u32 adapter_id; +}; + +struct kvm_kernel_irq_routing_entry { + u32 gsi; + u32 type; + int (*set)(struct kvm_kernel_irq_routing_entry *e, + struct kvm *kvm, int irq_source_id, int level, + bool line_status); + union { + struct { + unsigned irqchip; + unsigned pin; + } irqchip; + struct msi_msg msi; + struct kvm_s390_adapter_int adapter; + }; + struct hlist_node link; +}; + +#ifndef KVM_PRIVATE_MEM_SLOTS +#define KVM_PRIVATE_MEM_SLOTS 0 +#endif + +#ifndef KVM_MEM_SLOTS_NUM +#define KVM_MEM_SLOTS_NUM (KVM_USER_MEM_SLOTS + KVM_PRIVATE_MEM_SLOTS) +#endif + +/* + * Note: + * memslots are not sorted by id anymore, please use id_to_memslot() + * to get the memslot by its id. + */ +struct kvm_memslots { + u64 generation; + struct kvm_memory_slot memslots[KVM_MEM_SLOTS_NUM]; + /* The mapping table from slot id to the index in memslots[]. */ + short id_to_index[KVM_MEM_SLOTS_NUM]; +}; + +struct kvm { + spinlock_t mmu_lock; + struct mutex slots_lock; + struct mm_struct *mm; /* userspace tied to this vm */ + struct kvm_memslots *memslots; + struct srcu_struct srcu; + struct srcu_struct irq_srcu; +#ifdef CONFIG_KVM_APIC_ARCHITECTURE + u32 bsp_vcpu_id; +#endif + struct kvm_vcpu *vcpus[KVM_MAX_VCPUS]; + atomic_t online_vcpus; + int last_boosted_vcpu; + struct list_head vm_list; + struct mutex lock; + struct kvm_io_bus *buses[KVM_NR_BUSES]; +#ifdef CONFIG_HAVE_KVM_EVENTFD + struct { + spinlock_t lock; + struct list_head items; + struct list_head resampler_list; + struct mutex resampler_lock; + } irqfds; + struct list_head ioeventfds; +#endif + struct kvm_vm_stat stat; + struct kvm_arch arch; + atomic_t users_count; +#ifdef KVM_COALESCED_MMIO_PAGE_OFFSET + struct kvm_coalesced_mmio_ring *coalesced_mmio_ring; + spinlock_t ring_lock; + struct list_head coalesced_zones; +#endif + + struct mutex irq_lock; +#ifdef CONFIG_HAVE_KVM_IRQCHIP + /* + * Update side is protected by irq_lock. + */ + struct kvm_irq_routing_table __rcu *irq_routing; + struct hlist_head mask_notifier_list; +#endif +#ifdef CONFIG_HAVE_KVM_IRQFD + struct hlist_head irq_ack_notifier_list; +#endif + +#if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER) + struct mmu_notifier mmu_notifier; + unsigned long mmu_notifier_seq; + long mmu_notifier_count; +#endif + long tlbs_dirty; + struct list_head devices; +}; + +#define kvm_err(fmt, ...) \ + pr_err("kvm [%i]: " fmt, task_pid_nr(current), ## __VA_ARGS__) +#define kvm_info(fmt, ...) \ + pr_info("kvm [%i]: " fmt, task_pid_nr(current), ## __VA_ARGS__) +#define kvm_debug(fmt, ...) \ + pr_debug("kvm [%i]: " fmt, task_pid_nr(current), ## __VA_ARGS__) +#define kvm_pr_unimpl(fmt, ...) \ + pr_err_ratelimited("kvm [%i]: " fmt, \ + task_tgid_nr(current), ## __VA_ARGS__) + +/* The guest did something we don't support. */ +#define vcpu_unimpl(vcpu, fmt, ...) \ + kvm_pr_unimpl("vcpu%i " fmt, (vcpu)->vcpu_id, ## __VA_ARGS__) + +static inline struct kvm_vcpu *kvm_get_vcpu(struct kvm *kvm, int i) +{ + smp_rmb(); + return kvm->vcpus[i]; +} + +#define kvm_for_each_vcpu(idx, vcpup, kvm) \ + for (idx = 0; \ + idx < atomic_read(&kvm->online_vcpus) && \ + (vcpup = kvm_get_vcpu(kvm, idx)) != NULL; \ + idx++) + +#define kvm_for_each_memslot(memslot, slots) \ + for (memslot = &slots->memslots[0]; \ + memslot < slots->memslots + KVM_MEM_SLOTS_NUM && memslot->npages;\ + memslot++) + +int kvm_vcpu_init(struct kvm_vcpu *vcpu, struct kvm *kvm, unsigned id); +void kvm_vcpu_uninit(struct kvm_vcpu *vcpu); + +int __must_check vcpu_load(struct kvm_vcpu *vcpu); +void vcpu_put(struct kvm_vcpu *vcpu); + +#ifdef CONFIG_HAVE_KVM_IRQFD +int kvm_irqfd_init(void); +void kvm_irqfd_exit(void); +#else +static inline int kvm_irqfd_init(void) +{ + return 0; +} + +static inline void kvm_irqfd_exit(void) +{ +} +#endif +int kvm_init(void *opaque, unsigned vcpu_size, unsigned vcpu_align, + struct module *module); +void kvm_exit(void); + +void kvm_get_kvm(struct kvm *kvm); +void kvm_put_kvm(struct kvm *kvm); + +static inline struct kvm_memslots *kvm_memslots(struct kvm *kvm) +{ + return rcu_dereference_check(kvm->memslots, + srcu_read_lock_held(&kvm->srcu) + || lockdep_is_held(&kvm->slots_lock)); +} + +static inline struct kvm_memory_slot * +id_to_memslot(struct kvm_memslots *slots, int id) +{ + int index = slots->id_to_index[id]; + struct kvm_memory_slot *slot; + + slot = &slots->memslots[index]; + + WARN_ON(slot->id != id); + return slot; +} + +/* + * KVM_SET_USER_MEMORY_REGION ioctl allows the following operations: + * - create a new memory slot + * - delete an existing memory slot + * - modify an existing memory slot + * -- move it in the guest physical memory space + * -- just change its flags + * + * Since flags can be changed by some of these operations, the following + * differentiation is the best we can do for __kvm_set_memory_region(): + */ +enum kvm_mr_change { + KVM_MR_CREATE, + KVM_MR_DELETE, + KVM_MR_MOVE, + KVM_MR_FLAGS_ONLY, +}; + +int kvm_set_memory_region(struct kvm *kvm, + struct kvm_userspace_memory_region *mem); +int __kvm_set_memory_region(struct kvm *kvm, + struct kvm_userspace_memory_region *mem); +void kvm_arch_free_memslot(struct kvm *kvm, struct kvm_memory_slot *free, + struct kvm_memory_slot *dont); +int kvm_arch_create_memslot(struct kvm *kvm, struct kvm_memory_slot *slot, + unsigned long npages); +void kvm_arch_memslots_updated(struct kvm *kvm); +int kvm_arch_prepare_memory_region(struct kvm *kvm, + struct kvm_memory_slot *memslot, + struct kvm_userspace_memory_region *mem, + enum kvm_mr_change change); +void kvm_arch_commit_memory_region(struct kvm *kvm, + struct kvm_userspace_memory_region *mem, + const struct kvm_memory_slot *old, + enum kvm_mr_change change); +bool kvm_largepages_enabled(void); +void kvm_disable_largepages(void); +/* flush all memory translations */ +void kvm_arch_flush_shadow_all(struct kvm *kvm); +/* flush memory translations pointing to 'slot' */ +void kvm_arch_flush_shadow_memslot(struct kvm *kvm, + struct kvm_memory_slot *slot); + +int gfn_to_page_many_atomic(struct kvm *kvm, gfn_t gfn, struct page **pages, + int nr_pages); + +struct page *gfn_to_page(struct kvm *kvm, gfn_t gfn); +unsigned long gfn_to_hva(struct kvm *kvm, gfn_t gfn); +unsigned long gfn_to_hva_prot(struct kvm *kvm, gfn_t gfn, bool *writable); +unsigned long gfn_to_hva_memslot(struct kvm_memory_slot *slot, gfn_t gfn); +unsigned long gfn_to_hva_memslot_prot(struct kvm_memory_slot *slot, gfn_t gfn, + bool *writable); +void kvm_release_page_clean(struct page *page); +void kvm_release_page_dirty(struct page *page); +void kvm_set_page_accessed(struct page *page); + +pfn_t gfn_to_pfn_atomic(struct kvm *kvm, gfn_t gfn); +pfn_t gfn_to_pfn_async(struct kvm *kvm, gfn_t gfn, bool *async, + bool write_fault, bool *writable); +pfn_t gfn_to_pfn(struct kvm *kvm, gfn_t gfn); +pfn_t gfn_to_pfn_prot(struct kvm *kvm, gfn_t gfn, bool write_fault, + bool *writable); +pfn_t gfn_to_pfn_memslot(struct kvm_memory_slot *slot, gfn_t gfn); +pfn_t gfn_to_pfn_memslot_atomic(struct kvm_memory_slot *slot, gfn_t gfn); + +void kvm_release_pfn_clean(pfn_t pfn); +void kvm_set_pfn_dirty(pfn_t pfn); +void kvm_set_pfn_accessed(pfn_t pfn); +void kvm_get_pfn(pfn_t pfn); + +int kvm_read_guest_page(struct kvm *kvm, gfn_t gfn, void *data, int offset, + int len); +int kvm_read_guest_atomic(struct kvm *kvm, gpa_t gpa, void *data, + unsigned long len); +int kvm_read_guest(struct kvm *kvm, gpa_t gpa, void *data, unsigned long len); +int kvm_read_guest_cached(struct kvm *kvm, struct gfn_to_hva_cache *ghc, + void *data, unsigned long len); +int kvm_write_guest_page(struct kvm *kvm, gfn_t gfn, const void *data, + int offset, int len); +int kvm_write_guest(struct kvm *kvm, gpa_t gpa, const void *data, + unsigned long len); +int kvm_write_guest_cached(struct kvm *kvm, struct gfn_to_hva_cache *ghc, + void *data, unsigned long len); +int kvm_gfn_to_hva_cache_init(struct kvm *kvm, struct gfn_to_hva_cache *ghc, + gpa_t gpa, unsigned long len); +int kvm_clear_guest_page(struct kvm *kvm, gfn_t gfn, int offset, int len); +int kvm_clear_guest(struct kvm *kvm, gpa_t gpa, unsigned long len); +struct kvm_memory_slot *gfn_to_memslot(struct kvm *kvm, gfn_t gfn); +int kvm_is_visible_gfn(struct kvm *kvm, gfn_t gfn); +unsigned long kvm_host_page_size(struct kvm *kvm, gfn_t gfn); +void mark_page_dirty(struct kvm *kvm, gfn_t gfn); + +void kvm_vcpu_block(struct kvm_vcpu *vcpu); +void kvm_vcpu_kick(struct kvm_vcpu *vcpu); +int kvm_vcpu_yield_to(struct kvm_vcpu *target); +void kvm_vcpu_on_spin(struct kvm_vcpu *vcpu); +void kvm_load_guest_fpu(struct kvm_vcpu *vcpu); +void kvm_put_guest_fpu(struct kvm_vcpu *vcpu); + +void kvm_flush_remote_tlbs(struct kvm *kvm); +void kvm_reload_remote_mmus(struct kvm *kvm); +void kvm_make_mclock_inprogress_request(struct kvm *kvm); +void kvm_make_scan_ioapic_request(struct kvm *kvm); +bool kvm_make_all_cpus_request(struct kvm *kvm, unsigned int req); + +long kvm_arch_dev_ioctl(struct file *filp, + unsigned int ioctl, unsigned long arg); +long kvm_arch_vcpu_ioctl(struct file *filp, + unsigned int ioctl, unsigned long arg); +int kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf); + +int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext); + +int kvm_get_dirty_log(struct kvm *kvm, + struct kvm_dirty_log *log, int *is_dirty); +int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm, + struct kvm_dirty_log *log); + +int kvm_vm_ioctl_irq_line(struct kvm *kvm, struct kvm_irq_level *irq_level, + bool line_status); +long kvm_arch_vm_ioctl(struct file *filp, + unsigned int ioctl, unsigned long arg); + +int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu); +int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu); + +int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu, + struct kvm_translation *tr); + +int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs); +int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs); +int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu, + struct kvm_sregs *sregs); +int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu, + struct kvm_sregs *sregs); +int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu, + struct kvm_mp_state *mp_state); +int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu, + struct kvm_mp_state *mp_state); +int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu, + struct kvm_guest_debug *dbg); +int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run); + +int kvm_arch_init(void *opaque); +void kvm_arch_exit(void); + +int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu); +void kvm_arch_vcpu_uninit(struct kvm_vcpu *vcpu); + +void kvm_arch_sched_in(struct kvm_vcpu *vcpu, int cpu); + +void kvm_arch_vcpu_free(struct kvm_vcpu *vcpu); +void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu); +void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu); +struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm, unsigned int id); +int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu); +int kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu); +void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu); + +int kvm_arch_hardware_enable(void); +void kvm_arch_hardware_disable(void); +int kvm_arch_hardware_setup(void); +void kvm_arch_hardware_unsetup(void); +void kvm_arch_check_processor_compat(void *rtn); +int kvm_arch_vcpu_runnable(struct kvm_vcpu *vcpu); +int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu); + +void *kvm_kvzalloc(unsigned long size); +void kvm_kvfree(const void *addr); + +#ifndef __KVM_HAVE_ARCH_VM_ALLOC +static inline struct kvm *kvm_arch_alloc_vm(void) +{ + return kzalloc(sizeof(struct kvm), GFP_KERNEL); +} + +static inline void kvm_arch_free_vm(struct kvm *kvm) +{ + kfree(kvm); +} +#endif + +#ifdef __KVM_HAVE_ARCH_NONCOHERENT_DMA +void kvm_arch_register_noncoherent_dma(struct kvm *kvm); +void kvm_arch_unregister_noncoherent_dma(struct kvm *kvm); +bool kvm_arch_has_noncoherent_dma(struct kvm *kvm); +#else +static inline void kvm_arch_register_noncoherent_dma(struct kvm *kvm) +{ +} + +static inline void kvm_arch_unregister_noncoherent_dma(struct kvm *kvm) +{ +} + +static inline bool kvm_arch_has_noncoherent_dma(struct kvm *kvm) +{ + return false; +} +#endif + +static inline wait_queue_head_t *kvm_arch_vcpu_wq(struct kvm_vcpu *vcpu) +{ +#ifdef __KVM_HAVE_ARCH_WQP + return vcpu->arch.wqp; +#else + return &vcpu->wq; +#endif +} + +int kvm_arch_init_vm(struct kvm *kvm, unsigned long type); +void kvm_arch_destroy_vm(struct kvm *kvm); +void kvm_arch_sync_events(struct kvm *kvm); + +int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu); +void kvm_vcpu_kick(struct kvm_vcpu *vcpu); + +bool kvm_is_reserved_pfn(pfn_t pfn); + +struct kvm_irq_ack_notifier { + struct hlist_node link; + unsigned gsi; + void (*irq_acked)(struct kvm_irq_ack_notifier *kian); +}; + +struct kvm_assigned_dev_kernel { + struct kvm_irq_ack_notifier ack_notifier; + struct list_head list; + int assigned_dev_id; + int host_segnr; + int host_busnr; + int host_devfn; + unsigned int entries_nr; + int host_irq; + bool host_irq_disabled; + bool pci_2_3; + struct msix_entry *host_msix_entries; + int guest_irq; + struct msix_entry *guest_msix_entries; + unsigned long irq_requested_type; + int irq_source_id; + int flags; + struct pci_dev *dev; + struct kvm *kvm; + spinlock_t intx_lock; + spinlock_t intx_mask_lock; + char irq_name[32]; + struct pci_saved_state *pci_saved_state; +}; + +struct kvm_irq_mask_notifier { + void (*func)(struct kvm_irq_mask_notifier *kimn, bool masked); + int irq; + struct hlist_node link; +}; + +void kvm_register_irq_mask_notifier(struct kvm *kvm, int irq, + struct kvm_irq_mask_notifier *kimn); +void kvm_unregister_irq_mask_notifier(struct kvm *kvm, int irq, + struct kvm_irq_mask_notifier *kimn); +void kvm_fire_mask_notifiers(struct kvm *kvm, unsigned irqchip, unsigned pin, + bool mask); + +int kvm_irq_map_gsi(struct kvm *kvm, + struct kvm_kernel_irq_routing_entry *entries, int gsi); +int kvm_irq_map_chip_pin(struct kvm *kvm, unsigned irqchip, unsigned pin); + +int kvm_set_irq(struct kvm *kvm, int irq_source_id, u32 irq, int level, + bool line_status); +int kvm_set_irq_inatomic(struct kvm *kvm, int irq_source_id, u32 irq, int level); +int kvm_set_msi(struct kvm_kernel_irq_routing_entry *irq_entry, struct kvm *kvm, + int irq_source_id, int level, bool line_status); +bool kvm_irq_has_notifier(struct kvm *kvm, unsigned irqchip, unsigned pin); +void kvm_notify_acked_irq(struct kvm *kvm, unsigned irqchip, unsigned pin); +void kvm_register_irq_ack_notifier(struct kvm *kvm, + struct kvm_irq_ack_notifier *kian); +void kvm_unregister_irq_ack_notifier(struct kvm *kvm, + struct kvm_irq_ack_notifier *kian); +int kvm_request_irq_source_id(struct kvm *kvm); +void kvm_free_irq_source_id(struct kvm *kvm, int irq_source_id); + +#ifdef CONFIG_KVM_DEVICE_ASSIGNMENT +int kvm_iommu_map_pages(struct kvm *kvm, struct kvm_memory_slot *slot); +void kvm_iommu_unmap_pages(struct kvm *kvm, struct kvm_memory_slot *slot); +int kvm_iommu_map_guest(struct kvm *kvm); +int kvm_iommu_unmap_guest(struct kvm *kvm); +int kvm_assign_device(struct kvm *kvm, + struct kvm_assigned_dev_kernel *assigned_dev); +int kvm_deassign_device(struct kvm *kvm, + struct kvm_assigned_dev_kernel *assigned_dev); +#else +static inline int kvm_iommu_map_pages(struct kvm *kvm, + struct kvm_memory_slot *slot) +{ + return 0; +} + +static inline void kvm_iommu_unmap_pages(struct kvm *kvm, + struct kvm_memory_slot *slot) +{ +} + +static inline int kvm_iommu_unmap_guest(struct kvm *kvm) +{ + return 0; +} +#endif + +static inline void kvm_guest_enter(void) +{ + unsigned long flags; + + BUG_ON(preemptible()); + + local_irq_save(flags); + guest_enter(); + local_irq_restore(flags); + + /* KVM does not hold any references to rcu protected data when it + * switches CPU into a guest mode. In fact switching to a guest mode + * is very similar to exiting to userspace from rcu point of view. In + * addition CPU may stay in a guest mode for quite a long time (up to + * one time slice). Lets treat guest mode as quiescent state, just like + * we do with user-mode execution. + */ + rcu_virt_note_context_switch(smp_processor_id()); +} + +static inline void kvm_guest_exit(void) +{ + unsigned long flags; + + local_irq_save(flags); + guest_exit(); + local_irq_restore(flags); +} + +/* + * search_memslots() and __gfn_to_memslot() are here because they are + * used in non-modular code in arch/powerpc/kvm/book3s_hv_rm_mmu.c. + * gfn_to_memslot() itself isn't here as an inline because that would + * bloat other code too much. + */ +static inline struct kvm_memory_slot * +search_memslots(struct kvm_memslots *slots, gfn_t gfn) +{ + struct kvm_memory_slot *memslot; + + kvm_for_each_memslot(memslot, slots) + if (gfn >= memslot->base_gfn && + gfn < memslot->base_gfn + memslot->npages) + return memslot; + + return NULL; +} + +static inline struct kvm_memory_slot * +__gfn_to_memslot(struct kvm_memslots *slots, gfn_t gfn) +{ + return search_memslots(slots, gfn); +} + +static inline unsigned long +__gfn_to_hva_memslot(struct kvm_memory_slot *slot, gfn_t gfn) +{ + return slot->userspace_addr + (gfn - slot->base_gfn) * PAGE_SIZE; +} + +static inline int memslot_id(struct kvm *kvm, gfn_t gfn) +{ + return gfn_to_memslot(kvm, gfn)->id; +} + +static inline gfn_t +hva_to_gfn_memslot(unsigned long hva, struct kvm_memory_slot *slot) +{ + gfn_t gfn_offset = (hva - slot->userspace_addr) >> PAGE_SHIFT; + + return slot->base_gfn + gfn_offset; +} + +static inline gpa_t gfn_to_gpa(gfn_t gfn) +{ + return (gpa_t)gfn << PAGE_SHIFT; +} + +static inline gfn_t gpa_to_gfn(gpa_t gpa) +{ + return (gfn_t)(gpa >> PAGE_SHIFT); +} + +static inline hpa_t pfn_to_hpa(pfn_t pfn) +{ + return (hpa_t)pfn << PAGE_SHIFT; +} + +static inline bool kvm_is_error_gpa(struct kvm *kvm, gpa_t gpa) +{ + unsigned long hva = gfn_to_hva(kvm, gpa_to_gfn(gpa)); + + return kvm_is_error_hva(hva); +} + +static inline void kvm_migrate_timers(struct kvm_vcpu *vcpu) +{ + set_bit(KVM_REQ_MIGRATE_TIMER, &vcpu->requests); +} + +enum kvm_stat_kind { + KVM_STAT_VM, + KVM_STAT_VCPU, +}; + +struct kvm_stats_debugfs_item { + const char *name; + int offset; + enum kvm_stat_kind kind; + struct dentry *dentry; +}; +extern struct kvm_stats_debugfs_item debugfs_entries[]; +extern struct dentry *kvm_debugfs_dir; + +#if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER) +static inline int mmu_notifier_retry(struct kvm *kvm, unsigned long mmu_seq) +{ + if (unlikely(kvm->mmu_notifier_count)) + return 1; + /* + * Ensure the read of mmu_notifier_count happens before the read + * of mmu_notifier_seq. This interacts with the smp_wmb() in + * mmu_notifier_invalidate_range_end to make sure that the caller + * either sees the old (non-zero) value of mmu_notifier_count or + * the new (incremented) value of mmu_notifier_seq. + * PowerPC Book3s HV KVM calls this under a per-page lock + * rather than under kvm->mmu_lock, for scalability, so + * can't rely on kvm->mmu_lock to keep things ordered. + */ + smp_rmb(); + if (kvm->mmu_notifier_seq != mmu_seq) + return 1; + return 0; +} +#endif + +#ifdef CONFIG_HAVE_KVM_IRQ_ROUTING + +#ifdef CONFIG_S390 +#define KVM_MAX_IRQ_ROUTES 4096 //FIXME: we can have more than that... +#else +#define KVM_MAX_IRQ_ROUTES 1024 +#endif + +int kvm_setup_default_irq_routing(struct kvm *kvm); +int kvm_set_irq_routing(struct kvm *kvm, + const struct kvm_irq_routing_entry *entries, + unsigned nr, + unsigned flags); +int kvm_set_routing_entry(struct kvm_kernel_irq_routing_entry *e, + const struct kvm_irq_routing_entry *ue); +void kvm_free_irq_routing(struct kvm *kvm); + +#else + +static inline void kvm_free_irq_routing(struct kvm *kvm) {} + +#endif + +int kvm_send_userspace_msi(struct kvm *kvm, struct kvm_msi *msi); + +#ifdef CONFIG_HAVE_KVM_EVENTFD + +void kvm_eventfd_init(struct kvm *kvm); +int kvm_ioeventfd(struct kvm *kvm, struct kvm_ioeventfd *args); + +#ifdef CONFIG_HAVE_KVM_IRQFD +int kvm_irqfd(struct kvm *kvm, struct kvm_irqfd *args); +void kvm_irqfd_release(struct kvm *kvm); +void kvm_irq_routing_update(struct kvm *); +#else +static inline int kvm_irqfd(struct kvm *kvm, struct kvm_irqfd *args) +{ + return -EINVAL; +} + +static inline void kvm_irqfd_release(struct kvm *kvm) {} +#endif + +#else + +static inline void kvm_eventfd_init(struct kvm *kvm) {} + +static inline int kvm_irqfd(struct kvm *kvm, struct kvm_irqfd *args) +{ + return -EINVAL; +} + +static inline void kvm_irqfd_release(struct kvm *kvm) {} + +#ifdef CONFIG_HAVE_KVM_IRQCHIP +static inline void kvm_irq_routing_update(struct kvm *kvm) +{ +} +#endif + +static inline int kvm_ioeventfd(struct kvm *kvm, struct kvm_ioeventfd *args) +{ + return -ENOSYS; +} + +#endif /* CONFIG_HAVE_KVM_EVENTFD */ + +#ifdef CONFIG_KVM_APIC_ARCHITECTURE +static inline bool kvm_vcpu_is_bsp(struct kvm_vcpu *vcpu) +{ + return vcpu->kvm->bsp_vcpu_id == vcpu->vcpu_id; +} + +bool kvm_vcpu_compatible(struct kvm_vcpu *vcpu); + +#else + +static inline bool kvm_vcpu_compatible(struct kvm_vcpu *vcpu) { return true; } + +#endif + +#ifdef CONFIG_KVM_DEVICE_ASSIGNMENT + +long kvm_vm_ioctl_assigned_device(struct kvm *kvm, unsigned ioctl, + unsigned long arg); + +void kvm_free_all_assigned_devices(struct kvm *kvm); + +#else + +static inline long kvm_vm_ioctl_assigned_device(struct kvm *kvm, unsigned ioctl, + unsigned long arg) +{ + return -ENOTTY; +} + +static inline void kvm_free_all_assigned_devices(struct kvm *kvm) {} + +#endif + +static inline void kvm_make_request(int req, struct kvm_vcpu *vcpu) +{ + set_bit(req, &vcpu->requests); +} + +static inline bool kvm_check_request(int req, struct kvm_vcpu *vcpu) +{ + if (test_bit(req, &vcpu->requests)) { + clear_bit(req, &vcpu->requests); + return true; + } else { + return false; + } +} + +extern bool kvm_rebooting; + +struct kvm_device { + struct kvm_device_ops *ops; + struct kvm *kvm; + void *private; + struct list_head vm_node; +}; + +/* create, destroy, and name are mandatory */ +struct kvm_device_ops { + const char *name; + int (*create)(struct kvm_device *dev, u32 type); + + /* + * Destroy is responsible for freeing dev. + * + * Destroy may be called before or after destructors are called + * on emulated I/O regions, depending on whether a reference is + * held by a vcpu or other kvm component that gets destroyed + * after the emulated I/O. + */ + void (*destroy)(struct kvm_device *dev); + + int (*set_attr)(struct kvm_device *dev, struct kvm_device_attr *attr); + int (*get_attr)(struct kvm_device *dev, struct kvm_device_attr *attr); + int (*has_attr)(struct kvm_device *dev, struct kvm_device_attr *attr); + long (*ioctl)(struct kvm_device *dev, unsigned int ioctl, + unsigned long arg); +}; + +void kvm_device_get(struct kvm_device *dev); +void kvm_device_put(struct kvm_device *dev); +struct kvm_device *kvm_device_from_filp(struct file *filp); +int kvm_register_device_ops(struct kvm_device_ops *ops, u32 type); +void kvm_unregister_device_ops(u32 type); + +extern struct kvm_device_ops kvm_mpic_ops; +extern struct kvm_device_ops kvm_xics_ops; + +#ifdef CONFIG_HAVE_KVM_CPU_RELAX_INTERCEPT + +static inline void kvm_vcpu_set_in_spin_loop(struct kvm_vcpu *vcpu, bool val) +{ + vcpu->spin_loop.in_spin_loop = val; +} +static inline void kvm_vcpu_set_dy_eligible(struct kvm_vcpu *vcpu, bool val) +{ + vcpu->spin_loop.dy_eligible = val; +} + +#else /* !CONFIG_HAVE_KVM_CPU_RELAX_INTERCEPT */ + +static inline void kvm_vcpu_set_in_spin_loop(struct kvm_vcpu *vcpu, bool val) +{ +} + +static inline void kvm_vcpu_set_dy_eligible(struct kvm_vcpu *vcpu, bool val) +{ +} +#endif /* CONFIG_HAVE_KVM_CPU_RELAX_INTERCEPT */ +#endif + diff -Nur linux-3.18.14.orig/include/linux/lglock.h linux-3.18.14-rt/include/linux/lglock.h --- linux-3.18.14.orig/include/linux/lglock.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/lglock.h 2015-05-31 15:32:48.261635369 -0500 @@ -34,22 +34,39 @@ #endif struct lglock { +#ifndef CONFIG_PREEMPT_RT_FULL arch_spinlock_t __percpu *lock; +#else + struct rt_mutex __percpu *lock; +#endif #ifdef CONFIG_DEBUG_LOCK_ALLOC struct lock_class_key lock_key; struct lockdep_map lock_dep_map; #endif }; -#define DEFINE_LGLOCK(name) \ +#ifndef CONFIG_PREEMPT_RT_FULL +# define DEFINE_LGLOCK(name) \ static DEFINE_PER_CPU(arch_spinlock_t, name ## _lock) \ = __ARCH_SPIN_LOCK_UNLOCKED; \ struct lglock name = { .lock = &name ## _lock } -#define DEFINE_STATIC_LGLOCK(name) \ +# define DEFINE_STATIC_LGLOCK(name) \ static DEFINE_PER_CPU(arch_spinlock_t, name ## _lock) \ = __ARCH_SPIN_LOCK_UNLOCKED; \ static struct lglock name = { .lock = &name ## _lock } +#else + +# define DEFINE_LGLOCK(name) \ + static DEFINE_PER_CPU(struct rt_mutex, name ## _lock) \ + = __RT_MUTEX_INITIALIZER( name ## _lock); \ + struct lglock name = { .lock = &name ## _lock } + +# define DEFINE_STATIC_LGLOCK(name) \ + static DEFINE_PER_CPU(struct rt_mutex, name ## _lock) \ + = __RT_MUTEX_INITIALIZER( name ## _lock); \ + static struct lglock name = { .lock = &name ## _lock } +#endif void lg_lock_init(struct lglock *lg, char *name); void lg_local_lock(struct lglock *lg); @@ -59,6 +76,12 @@ void lg_global_lock(struct lglock *lg); void lg_global_unlock(struct lglock *lg); +#ifndef CONFIG_PREEMPT_RT_FULL +#define lg_global_trylock_relax(name) lg_global_lock(name) +#else +void lg_global_trylock_relax(struct lglock *lg); +#endif + #else /* When !CONFIG_SMP, map lglock to spinlock */ #define lglock spinlock diff -Nur linux-3.18.14.orig/include/linux/list_bl.h linux-3.18.14-rt/include/linux/list_bl.h --- linux-3.18.14.orig/include/linux/list_bl.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/list_bl.h 2015-05-31 15:32:48.265635369 -0500 @@ -2,6 +2,7 @@ #define _LINUX_LIST_BL_H #include +#include #include /* @@ -32,13 +33,22 @@ struct hlist_bl_head { struct hlist_bl_node *first; +#ifdef CONFIG_PREEMPT_RT_BASE + raw_spinlock_t lock; +#endif }; struct hlist_bl_node { struct hlist_bl_node *next, **pprev; }; -#define INIT_HLIST_BL_HEAD(ptr) \ - ((ptr)->first = NULL) + +static inline void INIT_HLIST_BL_HEAD(struct hlist_bl_head *h) +{ + h->first = NULL; +#ifdef CONFIG_PREEMPT_RT_BASE + raw_spin_lock_init(&h->lock); +#endif +} static inline void INIT_HLIST_BL_NODE(struct hlist_bl_node *h) { @@ -117,12 +127,26 @@ static inline void hlist_bl_lock(struct hlist_bl_head *b) { +#ifndef CONFIG_PREEMPT_RT_BASE bit_spin_lock(0, (unsigned long *)b); +#else + raw_spin_lock(&b->lock); +#if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK) + __set_bit(0, (unsigned long *)b); +#endif +#endif } static inline void hlist_bl_unlock(struct hlist_bl_head *b) { +#ifndef CONFIG_PREEMPT_RT_BASE __bit_spin_unlock(0, (unsigned long *)b); +#else +#if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK) + __clear_bit(0, (unsigned long *)b); +#endif + raw_spin_unlock(&b->lock); +#endif } static inline bool hlist_bl_is_locked(struct hlist_bl_head *b) diff -Nur linux-3.18.14.orig/include/linux/locallock.h linux-3.18.14-rt/include/linux/locallock.h --- linux-3.18.14.orig/include/linux/locallock.h 1969-12-31 18:00:00.000000000 -0600 +++ linux-3.18.14-rt/include/linux/locallock.h 2015-05-31 15:32:48.273635368 -0500 @@ -0,0 +1,270 @@ +#ifndef _LINUX_LOCALLOCK_H +#define _LINUX_LOCALLOCK_H + +#include +#include + +#ifdef CONFIG_PREEMPT_RT_BASE + +#ifdef CONFIG_DEBUG_SPINLOCK +# define LL_WARN(cond) WARN_ON(cond) +#else +# define LL_WARN(cond) do { } while (0) +#endif + +/* + * per cpu lock based substitute for local_irq_*() + */ +struct local_irq_lock { + spinlock_t lock; + struct task_struct *owner; + int nestcnt; + unsigned long flags; +}; + +#define DEFINE_LOCAL_IRQ_LOCK(lvar) \ + DEFINE_PER_CPU(struct local_irq_lock, lvar) = { \ + .lock = __SPIN_LOCK_UNLOCKED((lvar).lock) } + +#define DECLARE_LOCAL_IRQ_LOCK(lvar) \ + DECLARE_PER_CPU(struct local_irq_lock, lvar) + +#define local_irq_lock_init(lvar) \ + do { \ + int __cpu; \ + for_each_possible_cpu(__cpu) \ + spin_lock_init(&per_cpu(lvar, __cpu).lock); \ + } while (0) + +/* + * spin_lock|trylock|unlock_local flavour that does not migrate disable + * used for __local_lock|trylock|unlock where get_local_var/put_local_var + * already takes care of the migrate_disable/enable + * for CONFIG_PREEMPT_BASE map to the normal spin_* calls. + */ +#ifdef CONFIG_PREEMPT_RT_FULL +# define spin_lock_local(lock) rt_spin_lock(lock) +# define spin_trylock_local(lock) rt_spin_trylock(lock) +# define spin_unlock_local(lock) rt_spin_unlock(lock) +#else +# define spin_lock_local(lock) spin_lock(lock) +# define spin_trylock_local(lock) spin_trylock(lock) +# define spin_unlock_local(lock) spin_unlock(lock) +#endif + +static inline void __local_lock(struct local_irq_lock *lv) +{ + if (lv->owner != current) { + spin_lock_local(&lv->lock); + LL_WARN(lv->owner); + LL_WARN(lv->nestcnt); + lv->owner = current; + } + lv->nestcnt++; +} + +#define local_lock(lvar) \ + do { __local_lock(&get_local_var(lvar)); } while (0) + +static inline int __local_trylock(struct local_irq_lock *lv) +{ + if (lv->owner != current && spin_trylock_local(&lv->lock)) { + LL_WARN(lv->owner); + LL_WARN(lv->nestcnt); + lv->owner = current; + lv->nestcnt = 1; + return 1; + } + return 0; +} + +#define local_trylock(lvar) \ + ({ \ + int __locked; \ + __locked = __local_trylock(&get_local_var(lvar)); \ + if (!__locked) \ + put_local_var(lvar); \ + __locked; \ + }) + +static inline void __local_unlock(struct local_irq_lock *lv) +{ + LL_WARN(lv->nestcnt == 0); + LL_WARN(lv->owner != current); + if (--lv->nestcnt) + return; + + lv->owner = NULL; + spin_unlock_local(&lv->lock); +} + +#define local_unlock(lvar) \ + do { \ + __local_unlock(&__get_cpu_var(lvar)); \ + put_local_var(lvar); \ + } while (0) + +static inline void __local_lock_irq(struct local_irq_lock *lv) +{ + spin_lock_irqsave(&lv->lock, lv->flags); + LL_WARN(lv->owner); + LL_WARN(lv->nestcnt); + lv->owner = current; + lv->nestcnt = 1; +} + +#define local_lock_irq(lvar) \ + do { __local_lock_irq(&get_local_var(lvar)); } while (0) + +#define local_lock_irq_on(lvar, cpu) \ + do { __local_lock_irq(&per_cpu(lvar, cpu)); } while (0) + +static inline void __local_unlock_irq(struct local_irq_lock *lv) +{ + LL_WARN(!lv->nestcnt); + LL_WARN(lv->owner != current); + lv->owner = NULL; + lv->nestcnt = 0; + spin_unlock_irq(&lv->lock); +} + +#define local_unlock_irq(lvar) \ + do { \ + __local_unlock_irq(&__get_cpu_var(lvar)); \ + put_local_var(lvar); \ + } while (0) + +#define local_unlock_irq_on(lvar, cpu) \ + do { \ + __local_unlock_irq(&per_cpu(lvar, cpu)); \ + } while (0) + +static inline int __local_lock_irqsave(struct local_irq_lock *lv) +{ + if (lv->owner != current) { + __local_lock_irq(lv); + return 0; + } else { + lv->nestcnt++; + return 1; + } +} + +#define local_lock_irqsave(lvar, _flags) \ + do { \ + if (__local_lock_irqsave(&get_local_var(lvar))) \ + put_local_var(lvar); \ + _flags = __get_cpu_var(lvar).flags; \ + } while (0) + +#define local_lock_irqsave_on(lvar, _flags, cpu) \ + do { \ + __local_lock_irqsave(&per_cpu(lvar, cpu)); \ + _flags = per_cpu(lvar, cpu).flags; \ + } while (0) + +static inline int __local_unlock_irqrestore(struct local_irq_lock *lv, + unsigned long flags) +{ + LL_WARN(!lv->nestcnt); + LL_WARN(lv->owner != current); + if (--lv->nestcnt) + return 0; + + lv->owner = NULL; + spin_unlock_irqrestore(&lv->lock, lv->flags); + return 1; +} + +#define local_unlock_irqrestore(lvar, flags) \ + do { \ + if (__local_unlock_irqrestore(&__get_cpu_var(lvar), flags)) \ + put_local_var(lvar); \ + } while (0) + +#define local_unlock_irqrestore_on(lvar, flags, cpu) \ + do { \ + __local_unlock_irqrestore(&per_cpu(lvar, cpu), flags); \ + } while (0) + +#define local_spin_trylock_irq(lvar, lock) \ + ({ \ + int __locked; \ + local_lock_irq(lvar); \ + __locked = spin_trylock(lock); \ + if (!__locked) \ + local_unlock_irq(lvar); \ + __locked; \ + }) + +#define local_spin_lock_irq(lvar, lock) \ + do { \ + local_lock_irq(lvar); \ + spin_lock(lock); \ + } while (0) + +#define local_spin_unlock_irq(lvar, lock) \ + do { \ + spin_unlock(lock); \ + local_unlock_irq(lvar); \ + } while (0) + +#define local_spin_lock_irqsave(lvar, lock, flags) \ + do { \ + local_lock_irqsave(lvar, flags); \ + spin_lock(lock); \ + } while (0) + +#define local_spin_unlock_irqrestore(lvar, lock, flags) \ + do { \ + spin_unlock(lock); \ + local_unlock_irqrestore(lvar, flags); \ + } while (0) + +#define get_locked_var(lvar, var) \ + (*({ \ + local_lock(lvar); \ + &__get_cpu_var(var); \ + })) + +#define put_locked_var(lvar, var) local_unlock(lvar); + +#define local_lock_cpu(lvar) \ + ({ \ + local_lock(lvar); \ + smp_processor_id(); \ + }) + +#define local_unlock_cpu(lvar) local_unlock(lvar) + +#else /* PREEMPT_RT_BASE */ + +#define DEFINE_LOCAL_IRQ_LOCK(lvar) __typeof__(const int) lvar +#define DECLARE_LOCAL_IRQ_LOCK(lvar) extern __typeof__(const int) lvar + +static inline void local_irq_lock_init(int lvar) { } + +#define local_lock(lvar) preempt_disable() +#define local_unlock(lvar) preempt_enable() +#define local_lock_irq(lvar) local_irq_disable() +#define local_unlock_irq(lvar) local_irq_enable() +#define local_lock_irqsave(lvar, flags) local_irq_save(flags) +#define local_unlock_irqrestore(lvar, flags) local_irq_restore(flags) + +#define local_spin_trylock_irq(lvar, lock) spin_trylock_irq(lock) +#define local_spin_lock_irq(lvar, lock) spin_lock_irq(lock) +#define local_spin_unlock_irq(lvar, lock) spin_unlock_irq(lock) +#define local_spin_lock_irqsave(lvar, lock, flags) \ + spin_lock_irqsave(lock, flags) +#define local_spin_unlock_irqrestore(lvar, lock, flags) \ + spin_unlock_irqrestore(lock, flags) + +#define get_locked_var(lvar, var) get_cpu_var(var) +#define put_locked_var(lvar, var) put_cpu_var(var) + +#define local_lock_cpu(lvar) get_cpu() +#define local_unlock_cpu(lvar) put_cpu() + +#endif + +#endif diff -Nur linux-3.18.14.orig/include/linux/mm_types.h linux-3.18.14-rt/include/linux/mm_types.h --- linux-3.18.14.orig/include/linux/mm_types.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/mm_types.h 2015-05-31 15:32:48.273635368 -0500 @@ -11,6 +11,7 @@ #include #include #include +#include #include #include #include @@ -454,6 +455,9 @@ bool tlb_flush_pending; #endif struct uprobes_state uprobes_state; +#ifdef CONFIG_PREEMPT_RT_BASE + struct rcu_head delayed_drop; +#endif }; static inline void mm_init_cpumask(struct mm_struct *mm) diff -Nur linux-3.18.14.orig/include/linux/mutex.h linux-3.18.14-rt/include/linux/mutex.h --- linux-3.18.14.orig/include/linux/mutex.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/mutex.h 2015-05-31 15:32:48.273635368 -0500 @@ -19,6 +19,17 @@ #include #include +#ifdef CONFIG_DEBUG_LOCK_ALLOC +# define __DEP_MAP_MUTEX_INITIALIZER(lockname) \ + , .dep_map = { .name = #lockname } +#else +# define __DEP_MAP_MUTEX_INITIALIZER(lockname) +#endif + +#ifdef CONFIG_PREEMPT_RT_FULL +# include +#else + /* * Simple, straightforward mutexes with strict semantics: * @@ -100,13 +111,6 @@ static inline void mutex_destroy(struct mutex *lock) {} #endif -#ifdef CONFIG_DEBUG_LOCK_ALLOC -# define __DEP_MAP_MUTEX_INITIALIZER(lockname) \ - , .dep_map = { .name = #lockname } -#else -# define __DEP_MAP_MUTEX_INITIALIZER(lockname) -#endif - #define __MUTEX_INITIALIZER(lockname) \ { .count = ATOMIC_INIT(1) \ , .wait_lock = __SPIN_LOCK_UNLOCKED(lockname.wait_lock) \ @@ -174,6 +178,8 @@ extern int mutex_trylock(struct mutex *lock); extern void mutex_unlock(struct mutex *lock); +#endif /* !PREEMPT_RT_FULL */ + extern int atomic_dec_and_mutex_lock(atomic_t *cnt, struct mutex *lock); #endif /* __LINUX_MUTEX_H */ diff -Nur linux-3.18.14.orig/include/linux/mutex_rt.h linux-3.18.14-rt/include/linux/mutex_rt.h --- linux-3.18.14.orig/include/linux/mutex_rt.h 1969-12-31 18:00:00.000000000 -0600 +++ linux-3.18.14-rt/include/linux/mutex_rt.h 2015-05-31 15:32:48.273635368 -0500 @@ -0,0 +1,84 @@ +#ifndef __LINUX_MUTEX_RT_H +#define __LINUX_MUTEX_RT_H + +#ifndef __LINUX_MUTEX_H +#error "Please include mutex.h" +#endif + +#include + +/* FIXME: Just for __lockfunc */ +#include + +struct mutex { + struct rt_mutex lock; +#ifdef CONFIG_DEBUG_LOCK_ALLOC + struct lockdep_map dep_map; +#endif +}; + +#define __MUTEX_INITIALIZER(mutexname) \ + { \ + .lock = __RT_MUTEX_INITIALIZER(mutexname.lock) \ + __DEP_MAP_MUTEX_INITIALIZER(mutexname) \ + } + +#define DEFINE_MUTEX(mutexname) \ + struct mutex mutexname = __MUTEX_INITIALIZER(mutexname) + +extern void __mutex_do_init(struct mutex *lock, const char *name, struct lock_class_key *key); +extern void __lockfunc _mutex_lock(struct mutex *lock); +extern int __lockfunc _mutex_lock_interruptible(struct mutex *lock); +extern int __lockfunc _mutex_lock_killable(struct mutex *lock); +extern void __lockfunc _mutex_lock_nested(struct mutex *lock, int subclass); +extern void __lockfunc _mutex_lock_nest_lock(struct mutex *lock, struct lockdep_map *nest_lock); +extern int __lockfunc _mutex_lock_interruptible_nested(struct mutex *lock, int subclass); +extern int __lockfunc _mutex_lock_killable_nested(struct mutex *lock, int subclass); +extern int __lockfunc _mutex_trylock(struct mutex *lock); +extern void __lockfunc _mutex_unlock(struct mutex *lock); + +#define mutex_is_locked(l) rt_mutex_is_locked(&(l)->lock) +#define mutex_lock(l) _mutex_lock(l) +#define mutex_lock_interruptible(l) _mutex_lock_interruptible(l) +#define mutex_lock_killable(l) _mutex_lock_killable(l) +#define mutex_trylock(l) _mutex_trylock(l) +#define mutex_unlock(l) _mutex_unlock(l) +#define mutex_destroy(l) rt_mutex_destroy(&(l)->lock) + +#ifdef CONFIG_DEBUG_LOCK_ALLOC +# define mutex_lock_nested(l, s) _mutex_lock_nested(l, s) +# define mutex_lock_interruptible_nested(l, s) \ + _mutex_lock_interruptible_nested(l, s) +# define mutex_lock_killable_nested(l, s) \ + _mutex_lock_killable_nested(l, s) + +# define mutex_lock_nest_lock(lock, nest_lock) \ +do { \ + typecheck(struct lockdep_map *, &(nest_lock)->dep_map); \ + _mutex_lock_nest_lock(lock, &(nest_lock)->dep_map); \ +} while (0) + +#else +# define mutex_lock_nested(l, s) _mutex_lock(l) +# define mutex_lock_interruptible_nested(l, s) \ + _mutex_lock_interruptible(l) +# define mutex_lock_killable_nested(l, s) \ + _mutex_lock_killable(l) +# define mutex_lock_nest_lock(lock, nest_lock) mutex_lock(lock) +#endif + +# define mutex_init(mutex) \ +do { \ + static struct lock_class_key __key; \ + \ + rt_mutex_init(&(mutex)->lock); \ + __mutex_do_init((mutex), #mutex, &__key); \ +} while (0) + +# define __mutex_init(mutex, name, key) \ +do { \ + rt_mutex_init(&(mutex)->lock); \ + __mutex_do_init((mutex), name, key); \ +} while (0) + +#endif diff -Nur linux-3.18.14.orig/include/linux/netdevice.h linux-3.18.14-rt/include/linux/netdevice.h --- linux-3.18.14.orig/include/linux/netdevice.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/netdevice.h 2015-05-31 15:32:48.305635368 -0500 @@ -2351,6 +2351,7 @@ unsigned int dropped; struct sk_buff_head input_pkt_queue; struct napi_struct backlog; + struct sk_buff_head tofree_queue; #ifdef CONFIG_NET_FLOW_LIMIT struct sd_flow_limit __rcu *flow_limit; diff -Nur linux-3.18.14.orig/include/linux/netfilter/x_tables.h linux-3.18.14-rt/include/linux/netfilter/x_tables.h --- linux-3.18.14.orig/include/linux/netfilter/x_tables.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/netfilter/x_tables.h 2015-05-31 15:32:48.305635368 -0500 @@ -3,6 +3,7 @@ #include +#include #include /** @@ -282,6 +283,8 @@ */ DECLARE_PER_CPU(seqcount_t, xt_recseq); +DECLARE_LOCAL_IRQ_LOCK(xt_write_lock); + /** * xt_write_recseq_begin - start of a write section * @@ -296,6 +299,9 @@ { unsigned int addend; + /* RT protection */ + local_lock(xt_write_lock); + /* * Low order bit of sequence is set if we already * called xt_write_recseq_begin(). @@ -326,6 +332,7 @@ /* this is kind of a write_seqcount_end(), but addend is 0 or 1 */ smp_wmb(); __this_cpu_add(xt_recseq.sequence, addend); + local_unlock(xt_write_lock); } /* diff -Nur linux-3.18.14.orig/include/linux/notifier.h linux-3.18.14-rt/include/linux/notifier.h --- linux-3.18.14.orig/include/linux/notifier.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/notifier.h 2015-05-31 15:32:48.305635368 -0500 @@ -6,7 +6,7 @@ * * Alan Cox */ - + #ifndef _LINUX_NOTIFIER_H #define _LINUX_NOTIFIER_H #include @@ -42,9 +42,7 @@ * in srcu_notifier_call_chain(): no cache bounces and no memory barriers. * As compensation, srcu_notifier_chain_unregister() is rather expensive. * SRCU notifier chains should be used when the chain will be called very - * often but notifier_blocks will seldom be removed. Also, SRCU notifier - * chains are slightly more difficult to use because they require special - * runtime initialization. + * often but notifier_blocks will seldom be removed. */ typedef int (*notifier_fn_t)(struct notifier_block *nb, @@ -88,7 +86,7 @@ (name)->head = NULL; \ } while (0) -/* srcu_notifier_heads must be initialized and cleaned up dynamically */ +/* srcu_notifier_heads must be cleaned up dynamically */ extern void srcu_init_notifier_head(struct srcu_notifier_head *nh); #define srcu_cleanup_notifier_head(name) \ cleanup_srcu_struct(&(name)->srcu); @@ -101,7 +99,13 @@ .head = NULL } #define RAW_NOTIFIER_INIT(name) { \ .head = NULL } -/* srcu_notifier_heads cannot be initialized statically */ + +#define SRCU_NOTIFIER_INIT(name, pcpu) \ + { \ + .mutex = __MUTEX_INITIALIZER(name.mutex), \ + .head = NULL, \ + .srcu = __SRCU_STRUCT_INIT(name.srcu, pcpu), \ + } #define ATOMIC_NOTIFIER_HEAD(name) \ struct atomic_notifier_head name = \ @@ -113,6 +117,18 @@ struct raw_notifier_head name = \ RAW_NOTIFIER_INIT(name) +#define _SRCU_NOTIFIER_HEAD(name, mod) \ + static DEFINE_PER_CPU(struct srcu_struct_array, \ + name##_head_srcu_array); \ + mod struct srcu_notifier_head name = \ + SRCU_NOTIFIER_INIT(name, name##_head_srcu_array) + +#define SRCU_NOTIFIER_HEAD(name) \ + _SRCU_NOTIFIER_HEAD(name, ) + +#define SRCU_NOTIFIER_HEAD_STATIC(name) \ + _SRCU_NOTIFIER_HEAD(name, static) + #ifdef __KERNEL__ extern int atomic_notifier_chain_register(struct atomic_notifier_head *nh, @@ -182,12 +198,12 @@ /* * Declared notifiers so far. I can imagine quite a few more chains - * over time (eg laptop power reset chains, reboot chain (to clean + * over time (eg laptop power reset chains, reboot chain (to clean * device units up), device [un]mount chain, module load/unload chain, - * low memory chain, screenblank chain (for plug in modular screenblankers) + * low memory chain, screenblank chain (for plug in modular screenblankers) * VC switch chains (for loadable kernel svgalib VC switch helpers) etc... */ - + /* CPU notfiers are defined in include/linux/cpu.h. */ /* netdevice notifiers are defined in include/linux/netdevice.h */ diff -Nur linux-3.18.14.orig/include/linux/percpu.h linux-3.18.14-rt/include/linux/percpu.h --- linux-3.18.14.orig/include/linux/percpu.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/percpu.h 2015-05-31 15:32:48.305635368 -0500 @@ -23,6 +23,35 @@ PERCPU_MODULE_RESERVE) #endif +#ifdef CONFIG_PREEMPT_RT_FULL + +#define get_local_var(var) (*({ \ + migrate_disable(); \ + &__get_cpu_var(var); })) + +#define put_local_var(var) do { \ + (void)&(var); \ + migrate_enable(); \ +} while (0) + +# define get_local_ptr(var) ({ \ + migrate_disable(); \ + this_cpu_ptr(var); }) + +# define put_local_ptr(var) do { \ + (void)(var); \ + migrate_enable(); \ +} while (0) + +#else + +#define get_local_var(var) get_cpu_var(var) +#define put_local_var(var) put_cpu_var(var) +#define get_local_ptr(var) get_cpu_ptr(var) +#define put_local_ptr(var) put_cpu_ptr(var) + +#endif + /* minimum unit size, also is the maximum supported allocation size */ #define PCPU_MIN_UNIT_SIZE PFN_ALIGN(32 << 10) diff -Nur linux-3.18.14.orig/include/linux/pid.h linux-3.18.14-rt/include/linux/pid.h --- linux-3.18.14.orig/include/linux/pid.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/pid.h 2015-05-31 15:32:48.341635368 -0500 @@ -2,6 +2,7 @@ #define _LINUX_PID_H #include +#include enum pid_type { diff -Nur linux-3.18.14.orig/include/linux/preempt.h linux-3.18.14-rt/include/linux/preempt.h --- linux-3.18.14.orig/include/linux/preempt.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/preempt.h 2015-05-31 15:32:48.341635368 -0500 @@ -33,6 +33,20 @@ #define preempt_count_inc() preempt_count_add(1) #define preempt_count_dec() preempt_count_sub(1) +#ifdef CONFIG_PREEMPT_LAZY +#define add_preempt_lazy_count(val) do { preempt_lazy_count() += (val); } while (0) +#define sub_preempt_lazy_count(val) do { preempt_lazy_count() -= (val); } while (0) +#define inc_preempt_lazy_count() add_preempt_lazy_count(1) +#define dec_preempt_lazy_count() sub_preempt_lazy_count(1) +#define preempt_lazy_count() (current_thread_info()->preempt_lazy_count) +#else +#define add_preempt_lazy_count(val) do { } while (0) +#define sub_preempt_lazy_count(val) do { } while (0) +#define inc_preempt_lazy_count() do { } while (0) +#define dec_preempt_lazy_count() do { } while (0) +#define preempt_lazy_count() (0) +#endif + #ifdef CONFIG_PREEMPT_COUNT #define preempt_disable() \ @@ -41,13 +55,25 @@ barrier(); \ } while (0) +#define preempt_lazy_disable() \ +do { \ + inc_preempt_lazy_count(); \ + barrier(); \ +} while (0) + #define sched_preempt_enable_no_resched() \ do { \ barrier(); \ preempt_count_dec(); \ } while (0) -#define preempt_enable_no_resched() sched_preempt_enable_no_resched() +#ifdef CONFIG_PREEMPT_RT_BASE +# define preempt_enable_no_resched() sched_preempt_enable_no_resched() +# define preempt_check_resched_rt() preempt_check_resched() +#else +# define preempt_enable_no_resched() preempt_enable() +# define preempt_check_resched_rt() barrier(); +#endif #ifdef CONFIG_PREEMPT #define preempt_enable() \ @@ -63,6 +89,13 @@ __preempt_schedule(); \ } while (0) +#define preempt_lazy_enable() \ +do { \ + dec_preempt_lazy_count(); \ + barrier(); \ + preempt_check_resched(); \ +} while (0) + #else #define preempt_enable() \ do { \ @@ -121,6 +154,7 @@ #define preempt_disable_notrace() barrier() #define preempt_enable_no_resched_notrace() barrier() #define preempt_enable_notrace() barrier() +#define preempt_check_resched_rt() barrier() #endif /* CONFIG_PREEMPT_COUNT */ @@ -140,10 +174,31 @@ } while (0) #define preempt_fold_need_resched() \ do { \ - if (tif_need_resched()) \ + if (tif_need_resched_now()) \ set_preempt_need_resched(); \ } while (0) +#ifdef CONFIG_PREEMPT_RT_FULL +# define preempt_disable_rt() preempt_disable() +# define preempt_enable_rt() preempt_enable() +# define preempt_disable_nort() barrier() +# define preempt_enable_nort() barrier() +# ifdef CONFIG_SMP + extern void migrate_disable(void); + extern void migrate_enable(void); +# else /* CONFIG_SMP */ +# define migrate_disable() barrier() +# define migrate_enable() barrier() +# endif /* CONFIG_SMP */ +#else +# define preempt_disable_rt() barrier() +# define preempt_enable_rt() barrier() +# define preempt_disable_nort() preempt_disable() +# define preempt_enable_nort() preempt_enable() +# define migrate_disable() preempt_disable() +# define migrate_enable() preempt_enable() +#endif + #ifdef CONFIG_PREEMPT_NOTIFIERS struct preempt_notifier; diff -Nur linux-3.18.14.orig/include/linux/preempt_mask.h linux-3.18.14-rt/include/linux/preempt_mask.h --- linux-3.18.14.orig/include/linux/preempt_mask.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/preempt_mask.h 2015-05-31 15:32:48.341635368 -0500 @@ -44,16 +44,26 @@ #define HARDIRQ_OFFSET (1UL << HARDIRQ_SHIFT) #define NMI_OFFSET (1UL << NMI_SHIFT) -#define SOFTIRQ_DISABLE_OFFSET (2 * SOFTIRQ_OFFSET) +#ifndef CONFIG_PREEMPT_RT_FULL +# define SOFTIRQ_DISABLE_OFFSET (2 * SOFTIRQ_OFFSET) +#else +# define SOFTIRQ_DISABLE_OFFSET (0) +#endif #define PREEMPT_ACTIVE_BITS 1 #define PREEMPT_ACTIVE_SHIFT (NMI_SHIFT + NMI_BITS) #define PREEMPT_ACTIVE (__IRQ_MASK(PREEMPT_ACTIVE_BITS) << PREEMPT_ACTIVE_SHIFT) #define hardirq_count() (preempt_count() & HARDIRQ_MASK) -#define softirq_count() (preempt_count() & SOFTIRQ_MASK) #define irq_count() (preempt_count() & (HARDIRQ_MASK | SOFTIRQ_MASK \ | NMI_MASK)) +#ifndef CONFIG_PREEMPT_RT_FULL +# define softirq_count() (preempt_count() & SOFTIRQ_MASK) +# define in_serving_softirq() (softirq_count() & SOFTIRQ_OFFSET) +#else +# define softirq_count() (0UL) +extern int in_serving_softirq(void); +#endif /* * Are we doing bottom half or hardware interrupt processing? @@ -64,7 +74,6 @@ #define in_irq() (hardirq_count()) #define in_softirq() (softirq_count()) #define in_interrupt() (irq_count()) -#define in_serving_softirq() (softirq_count() & SOFTIRQ_OFFSET) /* * Are we in NMI context? diff -Nur linux-3.18.14.orig/include/linux/printk.h linux-3.18.14-rt/include/linux/printk.h --- linux-3.18.14.orig/include/linux/printk.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/printk.h 2015-05-31 15:32:48.341635368 -0500 @@ -119,9 +119,11 @@ extern asmlinkage __printf(1, 2) void early_printk(const char *fmt, ...); void early_vprintk(const char *fmt, va_list ap); +extern void printk_kill(void); #else static inline __printf(1, 2) __cold void early_printk(const char *s, ...) { } +static inline void printk_kill(void) { } #endif #ifdef CONFIG_PRINTK @@ -155,7 +157,6 @@ #define printk_ratelimit() __printk_ratelimit(__func__) extern bool printk_timed_ratelimit(unsigned long *caller_jiffies, unsigned int interval_msec); - extern int printk_delay_msec; extern int dmesg_restrict; extern int kptr_restrict; diff -Nur linux-3.18.14.orig/include/linux/radix-tree.h linux-3.18.14-rt/include/linux/radix-tree.h --- linux-3.18.14.orig/include/linux/radix-tree.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/radix-tree.h 2015-05-31 15:32:48.341635368 -0500 @@ -277,8 +277,13 @@ unsigned int radix_tree_gang_lookup_slot(struct radix_tree_root *root, void ***results, unsigned long *indices, unsigned long first_index, unsigned int max_items); +#ifndef CONFIG_PREEMPT_RT_FULL int radix_tree_preload(gfp_t gfp_mask); int radix_tree_maybe_preload(gfp_t gfp_mask); +#else +static inline int radix_tree_preload(gfp_t gm) { return 0; } +static inline int radix_tree_maybe_preload(gfp_t gfp_mask) { return 0; } +#endif void radix_tree_init(void); void *radix_tree_tag_set(struct radix_tree_root *root, unsigned long index, unsigned int tag); @@ -303,7 +308,7 @@ static inline void radix_tree_preload_end(void) { - preempt_enable(); + preempt_enable_nort(); } /** diff -Nur linux-3.18.14.orig/include/linux/random.h linux-3.18.14-rt/include/linux/random.h --- linux-3.18.14.orig/include/linux/random.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/random.h 2015-05-31 15:32:48.341635368 -0500 @@ -11,7 +11,7 @@ extern void add_device_randomness(const void *, unsigned int); extern void add_input_randomness(unsigned int type, unsigned int code, unsigned int value); -extern void add_interrupt_randomness(int irq, int irq_flags); +extern void add_interrupt_randomness(int irq, int irq_flags, __u64 ip); extern void get_random_bytes(void *buf, int nbytes); extern void get_random_bytes_arch(void *buf, int nbytes); diff -Nur linux-3.18.14.orig/include/linux/rcupdate.h linux-3.18.14-rt/include/linux/rcupdate.h --- linux-3.18.14.orig/include/linux/rcupdate.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/rcupdate.h 2015-05-31 15:32:48.341635368 -0500 @@ -147,6 +147,9 @@ #endif /* #else #ifdef CONFIG_PREEMPT_RCU */ +#ifdef CONFIG_PREEMPT_RT_FULL +#define call_rcu_bh call_rcu +#else /** * call_rcu_bh() - Queue an RCU for invocation after a quicker grace period. * @head: structure to be used for queueing the RCU updates. @@ -170,6 +173,7 @@ */ void call_rcu_bh(struct rcu_head *head, void (*func)(struct rcu_head *head)); +#endif /** * call_rcu_sched() - Queue an RCU for invocation after sched grace period. @@ -231,6 +235,11 @@ * types of kernel builds, the rcu_read_lock() nesting depth is unknowable. */ #define rcu_preempt_depth() (current->rcu_read_lock_nesting) +#ifndef CONFIG_PREEMPT_RT_FULL +#define sched_rcu_preempt_depth() rcu_preempt_depth() +#else +static inline int sched_rcu_preempt_depth(void) { return 0; } +#endif #else /* #ifdef CONFIG_PREEMPT_RCU */ @@ -254,6 +263,8 @@ return 0; } +#define sched_rcu_preempt_depth() rcu_preempt_depth() + #endif /* #else #ifdef CONFIG_PREEMPT_RCU */ /* Internal to kernel */ @@ -430,7 +441,14 @@ int debug_lockdep_rcu_enabled(void); int rcu_read_lock_held(void); +#ifdef CONFIG_PREEMPT_RT_FULL +static inline int rcu_read_lock_bh_held(void) +{ + return rcu_read_lock_held(); +} +#else int rcu_read_lock_bh_held(void); +#endif /** * rcu_read_lock_sched_held() - might we be in RCU-sched read-side critical section? @@ -955,10 +973,14 @@ static inline void rcu_read_lock_bh(void) { local_bh_disable(); +#ifdef CONFIG_PREEMPT_RT_FULL + rcu_read_lock(); +#else __acquire(RCU_BH); rcu_lock_acquire(&rcu_bh_lock_map); rcu_lockdep_assert(rcu_is_watching(), "rcu_read_lock_bh() used illegally while idle"); +#endif } /* @@ -968,10 +990,14 @@ */ static inline void rcu_read_unlock_bh(void) { +#ifdef CONFIG_PREEMPT_RT_FULL + rcu_read_unlock(); +#else rcu_lockdep_assert(rcu_is_watching(), "rcu_read_unlock_bh() used illegally while idle"); rcu_lock_release(&rcu_bh_lock_map); __release(RCU_BH); +#endif local_bh_enable(); } diff -Nur linux-3.18.14.orig/include/linux/rcutree.h linux-3.18.14-rt/include/linux/rcutree.h --- linux-3.18.14.orig/include/linux/rcutree.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/rcutree.h 2015-05-31 15:32:48.361635367 -0500 @@ -46,7 +46,11 @@ rcu_note_context_switch(cpu); } +#ifdef CONFIG_PREEMPT_RT_FULL +# define synchronize_rcu_bh synchronize_rcu +#else void synchronize_rcu_bh(void); +#endif void synchronize_sched_expedited(void); void synchronize_rcu_expedited(void); @@ -74,7 +78,11 @@ } void rcu_barrier(void); +#ifdef CONFIG_PREEMPT_RT_FULL +# define rcu_barrier_bh rcu_barrier +#else void rcu_barrier_bh(void); +#endif void rcu_barrier_sched(void); unsigned long get_state_synchronize_rcu(void); void cond_synchronize_rcu(unsigned long oldstate); @@ -82,12 +90,10 @@ extern unsigned long rcutorture_testseq; extern unsigned long rcutorture_vernum; long rcu_batches_completed(void); -long rcu_batches_completed_bh(void); long rcu_batches_completed_sched(void); void show_rcu_gp_kthreads(void); void rcu_force_quiescent_state(void); -void rcu_bh_force_quiescent_state(void); void rcu_sched_force_quiescent_state(void); void exit_rcu(void); @@ -97,4 +103,12 @@ bool rcu_is_watching(void); +#ifndef CONFIG_PREEMPT_RT_FULL +void rcu_bh_force_quiescent_state(void); +long rcu_batches_completed_bh(void); +#else +# define rcu_bh_force_quiescent_state rcu_force_quiescent_state +# define rcu_batches_completed_bh rcu_batches_completed +#endif + #endif /* __LINUX_RCUTREE_H */ diff -Nur linux-3.18.14.orig/include/linux/rtmutex.h linux-3.18.14-rt/include/linux/rtmutex.h --- linux-3.18.14.orig/include/linux/rtmutex.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/rtmutex.h 2015-05-31 15:32:48.377635367 -0500 @@ -14,10 +14,14 @@ #include #include -#include +#include extern int max_lock_depth; /* for sysctl */ +#ifdef CONFIG_DEBUG_MUTEXES +#include +#endif + /** * The rt_mutex structure * @@ -31,8 +35,8 @@ struct rb_root waiters; struct rb_node *waiters_leftmost; struct task_struct *owner; -#ifdef CONFIG_DEBUG_RT_MUTEXES int save_state; +#ifdef CONFIG_DEBUG_RT_MUTEXES const char *name, *file; int line; void *magic; @@ -55,22 +59,33 @@ # define rt_mutex_debug_check_no_locks_held(task) do { } while (0) #endif +# define rt_mutex_init(mutex) \ + do { \ + raw_spin_lock_init(&(mutex)->wait_lock); \ + __rt_mutex_init(mutex, #mutex); \ + } while (0) + #ifdef CONFIG_DEBUG_RT_MUTEXES # define __DEBUG_RT_MUTEX_INITIALIZER(mutexname) \ , .name = #mutexname, .file = __FILE__, .line = __LINE__ -# define rt_mutex_init(mutex) __rt_mutex_init(mutex, __func__) extern void rt_mutex_debug_task_free(struct task_struct *tsk); #else # define __DEBUG_RT_MUTEX_INITIALIZER(mutexname) -# define rt_mutex_init(mutex) __rt_mutex_init(mutex, NULL) # define rt_mutex_debug_task_free(t) do { } while (0) #endif -#define __RT_MUTEX_INITIALIZER(mutexname) \ - { .wait_lock = __RAW_SPIN_LOCK_UNLOCKED(mutexname.wait_lock) \ +#define __RT_MUTEX_INITIALIZER_PLAIN(mutexname) \ + .wait_lock = __RAW_SPIN_LOCK_UNLOCKED(mutexname.wait_lock) \ , .waiters = RB_ROOT \ , .owner = NULL \ - __DEBUG_RT_MUTEX_INITIALIZER(mutexname)} + __DEBUG_RT_MUTEX_INITIALIZER(mutexname) + +#define __RT_MUTEX_INITIALIZER(mutexname) \ + { __RT_MUTEX_INITIALIZER_PLAIN(mutexname) } + +#define __RT_MUTEX_INITIALIZER_SAVE_STATE(mutexname) \ + { __RT_MUTEX_INITIALIZER_PLAIN(mutexname) \ + , .save_state = 1 } #define DEFINE_RT_MUTEX(mutexname) \ struct rt_mutex mutexname = __RT_MUTEX_INITIALIZER(mutexname) @@ -91,6 +106,7 @@ extern void rt_mutex_lock(struct rt_mutex *lock); extern int rt_mutex_lock_interruptible(struct rt_mutex *lock); +extern int rt_mutex_lock_killable(struct rt_mutex *lock); extern int rt_mutex_timed_lock(struct rt_mutex *lock, struct hrtimer_sleeper *timeout); diff -Nur linux-3.18.14.orig/include/linux/rwlock_rt.h linux-3.18.14-rt/include/linux/rwlock_rt.h --- linux-3.18.14.orig/include/linux/rwlock_rt.h 1969-12-31 18:00:00.000000000 -0600 +++ linux-3.18.14-rt/include/linux/rwlock_rt.h 2015-05-31 15:32:48.377635367 -0500 @@ -0,0 +1,99 @@ +#ifndef __LINUX_RWLOCK_RT_H +#define __LINUX_RWLOCK_RT_H + +#ifndef __LINUX_SPINLOCK_H +#error Do not include directly. Use spinlock.h +#endif + +#define rwlock_init(rwl) \ +do { \ + static struct lock_class_key __key; \ + \ + rt_mutex_init(&(rwl)->lock); \ + __rt_rwlock_init(rwl, #rwl, &__key); \ +} while (0) + +extern void __lockfunc rt_write_lock(rwlock_t *rwlock); +extern void __lockfunc rt_read_lock(rwlock_t *rwlock); +extern int __lockfunc rt_write_trylock(rwlock_t *rwlock); +extern int __lockfunc rt_write_trylock_irqsave(rwlock_t *trylock, unsigned long *flags); +extern int __lockfunc rt_read_trylock(rwlock_t *rwlock); +extern void __lockfunc rt_write_unlock(rwlock_t *rwlock); +extern void __lockfunc rt_read_unlock(rwlock_t *rwlock); +extern unsigned long __lockfunc rt_write_lock_irqsave(rwlock_t *rwlock); +extern unsigned long __lockfunc rt_read_lock_irqsave(rwlock_t *rwlock); +extern void __rt_rwlock_init(rwlock_t *rwlock, char *name, struct lock_class_key *key); + +#define read_trylock(lock) __cond_lock(lock, rt_read_trylock(lock)) +#define write_trylock(lock) __cond_lock(lock, rt_write_trylock(lock)) + +#define write_trylock_irqsave(lock, flags) \ + __cond_lock(lock, rt_write_trylock_irqsave(lock, &flags)) + +#define read_lock_irqsave(lock, flags) \ + do { \ + typecheck(unsigned long, flags); \ + flags = rt_read_lock_irqsave(lock); \ + } while (0) + +#define write_lock_irqsave(lock, flags) \ + do { \ + typecheck(unsigned long, flags); \ + flags = rt_write_lock_irqsave(lock); \ + } while (0) + +#define read_lock(lock) rt_read_lock(lock) + +#define read_lock_bh(lock) \ + do { \ + local_bh_disable(); \ + rt_read_lock(lock); \ + } while (0) + +#define read_lock_irq(lock) read_lock(lock) + +#define write_lock(lock) rt_write_lock(lock) + +#define write_lock_bh(lock) \ + do { \ + local_bh_disable(); \ + rt_write_lock(lock); \ + } while (0) + +#define write_lock_irq(lock) write_lock(lock) + +#define read_unlock(lock) rt_read_unlock(lock) + +#define read_unlock_bh(lock) \ + do { \ + rt_read_unlock(lock); \ + local_bh_enable(); \ + } while (0) + +#define read_unlock_irq(lock) read_unlock(lock) + +#define write_unlock(lock) rt_write_unlock(lock) + +#define write_unlock_bh(lock) \ + do { \ + rt_write_unlock(lock); \ + local_bh_enable(); \ + } while (0) + +#define write_unlock_irq(lock) write_unlock(lock) + +#define read_unlock_irqrestore(lock, flags) \ + do { \ + typecheck(unsigned long, flags); \ + (void) flags; \ + rt_read_unlock(lock); \ + } while (0) + +#define write_unlock_irqrestore(lock, flags) \ + do { \ + typecheck(unsigned long, flags); \ + (void) flags; \ + rt_write_unlock(lock); \ + } while (0) + +#endif diff -Nur linux-3.18.14.orig/include/linux/rwlock_types.h linux-3.18.14-rt/include/linux/rwlock_types.h --- linux-3.18.14.orig/include/linux/rwlock_types.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/rwlock_types.h 2015-05-31 15:32:48.377635367 -0500 @@ -1,6 +1,10 @@ #ifndef __LINUX_RWLOCK_TYPES_H #define __LINUX_RWLOCK_TYPES_H +#if !defined(__LINUX_SPINLOCK_TYPES_H) +# error "Do not include directly, include spinlock_types.h" +#endif + /* * include/linux/rwlock_types.h - generic rwlock type definitions * and initializers @@ -43,6 +47,7 @@ RW_DEP_MAP_INIT(lockname) } #endif -#define DEFINE_RWLOCK(x) rwlock_t x = __RW_LOCK_UNLOCKED(x) +#define DEFINE_RWLOCK(name) \ + rwlock_t name __cacheline_aligned_in_smp = __RW_LOCK_UNLOCKED(name) #endif /* __LINUX_RWLOCK_TYPES_H */ diff -Nur linux-3.18.14.orig/include/linux/rwlock_types_rt.h linux-3.18.14-rt/include/linux/rwlock_types_rt.h --- linux-3.18.14.orig/include/linux/rwlock_types_rt.h 1969-12-31 18:00:00.000000000 -0600 +++ linux-3.18.14-rt/include/linux/rwlock_types_rt.h 2015-05-31 15:32:48.377635367 -0500 @@ -0,0 +1,33 @@ +#ifndef __LINUX_RWLOCK_TYPES_RT_H +#define __LINUX_RWLOCK_TYPES_RT_H + +#ifndef __LINUX_SPINLOCK_TYPES_H +#error "Do not include directly. Include spinlock_types.h instead" +#endif + +/* + * rwlocks - rtmutex which allows single reader recursion + */ +typedef struct { + struct rt_mutex lock; + int read_depth; + unsigned int break_lock; +#ifdef CONFIG_DEBUG_LOCK_ALLOC + struct lockdep_map dep_map; +#endif +} rwlock_t; + +#ifdef CONFIG_DEBUG_LOCK_ALLOC +# define RW_DEP_MAP_INIT(lockname) .dep_map = { .name = #lockname } +#else +# define RW_DEP_MAP_INIT(lockname) +#endif + +#define __RW_LOCK_UNLOCKED(name) \ + { .lock = __RT_MUTEX_INITIALIZER_SAVE_STATE(name.lock), \ + RW_DEP_MAP_INIT(name) } + +#define DEFINE_RWLOCK(name) \ + rwlock_t name __cacheline_aligned_in_smp = __RW_LOCK_UNLOCKED(name) + +#endif diff -Nur linux-3.18.14.orig/include/linux/rwsem.h linux-3.18.14-rt/include/linux/rwsem.h --- linux-3.18.14.orig/include/linux/rwsem.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/rwsem.h 2015-05-31 15:32:48.377635367 -0500 @@ -18,6 +18,10 @@ #include #endif +#ifdef CONFIG_PREEMPT_RT_FULL +#include +#else /* PREEMPT_RT_FULL */ + struct rw_semaphore; #ifdef CONFIG_RWSEM_GENERIC_SPINLOCK @@ -177,4 +181,6 @@ # define up_read_non_owner(sem) up_read(sem) #endif +#endif /* !PREEMPT_RT_FULL */ + #endif /* _LINUX_RWSEM_H */ diff -Nur linux-3.18.14.orig/include/linux/rwsem_rt.h linux-3.18.14-rt/include/linux/rwsem_rt.h --- linux-3.18.14.orig/include/linux/rwsem_rt.h 1969-12-31 18:00:00.000000000 -0600 +++ linux-3.18.14-rt/include/linux/rwsem_rt.h 2015-05-31 15:32:48.377635367 -0500 @@ -0,0 +1,134 @@ +#ifndef _LINUX_RWSEM_RT_H +#define _LINUX_RWSEM_RT_H + +#ifndef _LINUX_RWSEM_H +#error "Include rwsem.h" +#endif + +/* + * RW-semaphores are a spinlock plus a reader-depth count. + * + * Note that the semantics are different from the usual + * Linux rw-sems, in PREEMPT_RT mode we do not allow + * multiple readers to hold the lock at once, we only allow + * a read-lock owner to read-lock recursively. This is + * better for latency, makes the implementation inherently + * fair and makes it simpler as well. + */ + +#include + +struct rw_semaphore { + struct rt_mutex lock; + int read_depth; +#ifdef CONFIG_DEBUG_LOCK_ALLOC + struct lockdep_map dep_map; +#endif +}; + +#define __RWSEM_INITIALIZER(name) \ + { .lock = __RT_MUTEX_INITIALIZER(name.lock), \ + RW_DEP_MAP_INIT(name) } + +#define DECLARE_RWSEM(lockname) \ + struct rw_semaphore lockname = __RWSEM_INITIALIZER(lockname) + +extern void __rt_rwsem_init(struct rw_semaphore *rwsem, const char *name, + struct lock_class_key *key); + +#define __rt_init_rwsem(sem, name, key) \ + do { \ + rt_mutex_init(&(sem)->lock); \ + __rt_rwsem_init((sem), (name), (key));\ + } while (0) + +#define __init_rwsem(sem, name, key) __rt_init_rwsem(sem, name, key) + +# define rt_init_rwsem(sem) \ +do { \ + static struct lock_class_key __key; \ + \ + __rt_init_rwsem((sem), #sem, &__key); \ +} while (0) + +extern void rt_down_write(struct rw_semaphore *rwsem); +extern void rt_down_read_nested(struct rw_semaphore *rwsem, int subclass); +extern void rt_down_write_nested(struct rw_semaphore *rwsem, int subclass); +extern void rt_down_write_nested_lock(struct rw_semaphore *rwsem, + struct lockdep_map *nest); +extern void rt_down_read(struct rw_semaphore *rwsem); +extern int rt_down_write_trylock(struct rw_semaphore *rwsem); +extern int rt_down_read_trylock(struct rw_semaphore *rwsem); +extern void rt_up_read(struct rw_semaphore *rwsem); +extern void rt_up_write(struct rw_semaphore *rwsem); +extern void rt_downgrade_write(struct rw_semaphore *rwsem); + +#define init_rwsem(sem) rt_init_rwsem(sem) +#define rwsem_is_locked(s) rt_mutex_is_locked(&(s)->lock) + +static inline int rwsem_is_contended(struct rw_semaphore *sem) +{ + /* rt_mutex_has_waiters() */ + return !RB_EMPTY_ROOT(&sem->lock.waiters); +} + +static inline void down_read(struct rw_semaphore *sem) +{ + rt_down_read(sem); +} + +static inline int down_read_trylock(struct rw_semaphore *sem) +{ + return rt_down_read_trylock(sem); +} + +static inline void down_write(struct rw_semaphore *sem) +{ + rt_down_write(sem); +} + +static inline int down_write_trylock(struct rw_semaphore *sem) +{ + return rt_down_write_trylock(sem); +} + +static inline void up_read(struct rw_semaphore *sem) +{ + rt_up_read(sem); +} + +static inline void up_write(struct rw_semaphore *sem) +{ + rt_up_write(sem); +} + +static inline void downgrade_write(struct rw_semaphore *sem) +{ + rt_downgrade_write(sem); +} + +static inline void down_read_nested(struct rw_semaphore *sem, int subclass) +{ + return rt_down_read_nested(sem, subclass); +} + +static inline void down_write_nested(struct rw_semaphore *sem, int subclass) +{ + rt_down_write_nested(sem, subclass); +} +#ifdef CONFIG_DEBUG_LOCK_ALLOC +static inline void down_write_nest_lock(struct rw_semaphore *sem, + struct rw_semaphore *nest_lock) +{ + rt_down_write_nested_lock(sem, &nest_lock->dep_map); +} + +#else + +static inline void down_write_nest_lock(struct rw_semaphore *sem, + struct rw_semaphore *nest_lock) +{ + rt_down_write_nested_lock(sem, NULL); +} +#endif +#endif diff -Nur linux-3.18.14.orig/include/linux/sched.h linux-3.18.14-rt/include/linux/sched.h --- linux-3.18.14.orig/include/linux/sched.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/sched.h 2015-05-31 15:32:48.381635367 -0500 @@ -26,6 +26,7 @@ #include #include #include +#include #include #include @@ -56,6 +57,7 @@ #include #include #include +#include #include #include @@ -235,10 +237,7 @@ TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \ __TASK_TRACED | EXIT_ZOMBIE | EXIT_DEAD) -#define task_is_traced(task) ((task->state & __TASK_TRACED) != 0) #define task_is_stopped(task) ((task->state & __TASK_STOPPED) != 0) -#define task_is_stopped_or_traced(task) \ - ((task->state & (__TASK_STOPPED | __TASK_TRACED)) != 0) #define task_contributes_to_load(task) \ ((task->state & TASK_UNINTERRUPTIBLE) != 0 && \ (task->flags & PF_FROZEN) == 0) @@ -1234,6 +1233,7 @@ struct task_struct { volatile long state; /* -1 unrunnable, 0 runnable, >0 stopped */ + volatile long saved_state; /* saved state for "spinlock sleepers" */ void *stack; atomic_t usage; unsigned int flags; /* per process flags, defined below */ @@ -1270,6 +1270,12 @@ #endif unsigned int policy; +#ifdef CONFIG_PREEMPT_RT_FULL + int migrate_disable; +# ifdef CONFIG_SCHED_DEBUG + int migrate_disable_atomic; +# endif +#endif int nr_cpus_allowed; cpumask_t cpus_allowed; @@ -1371,7 +1377,8 @@ struct cputime prev_cputime; #endif #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN - seqlock_t vtime_seqlock; + raw_spinlock_t vtime_lock; + seqcount_t vtime_seq; unsigned long long vtime_snap; enum { VTIME_SLEEPING = 0, @@ -1387,6 +1394,9 @@ struct task_cputime cputime_expires; struct list_head cpu_timers[3]; +#ifdef CONFIG_PREEMPT_RT_BASE + struct task_struct *posix_timer_list; +#endif /* process credentials */ const struct cred __rcu *real_cred; /* objective and real subjective task @@ -1419,10 +1429,15 @@ /* signal handlers */ struct signal_struct *signal; struct sighand_struct *sighand; + struct sigqueue *sigqueue_cache; sigset_t blocked, real_blocked; sigset_t saved_sigmask; /* restored if set_restore_sigmask() was used */ struct sigpending pending; +#ifdef CONFIG_PREEMPT_RT_FULL + /* TODO: move me into ->restart_block ? */ + struct siginfo forced_info; +#endif unsigned long sas_ss_sp; size_t sas_ss_size; @@ -1460,6 +1475,9 @@ /* mutex deadlock detection */ struct mutex_waiter *blocked_on; #endif +#ifdef CONFIG_PREEMPT_RT_FULL + int pagefault_disabled; +#endif #ifdef CONFIG_TRACE_IRQFLAGS unsigned int irq_events; unsigned long hardirq_enable_ip; @@ -1644,6 +1662,12 @@ unsigned long trace; /* bitmask and counter of trace recursion */ unsigned long trace_recursion; +#ifdef CONFIG_WAKEUP_LATENCY_HIST + u64 preempt_timestamp_hist; +#ifdef CONFIG_MISSED_TIMER_OFFSETS_HIST + long timer_offset; +#endif +#endif #endif /* CONFIG_TRACING */ #ifdef CONFIG_MEMCG /* memcg uses this to do batch job */ unsigned int memcg_kmem_skip_account; @@ -1661,11 +1685,19 @@ unsigned int sequential_io; unsigned int sequential_io_avg; #endif +#ifdef CONFIG_PREEMPT_RT_BASE + struct rcu_head put_rcu; + int softirq_nestcnt; + unsigned int softirqs_raised; +#endif +#ifdef CONFIG_PREEMPT_RT_FULL +# if defined CONFIG_HIGHMEM || defined CONFIG_X86_32 + int kmap_idx; + pte_t kmap_pte[KM_TYPE_NR]; +# endif +#endif }; -/* Future-safe accessor for struct task_struct's cpus_allowed. */ -#define tsk_cpus_allowed(tsk) (&(tsk)->cpus_allowed) - #define TNF_MIGRATED 0x01 #define TNF_NO_GROUP 0x02 #define TNF_SHARED 0x04 @@ -1700,6 +1732,17 @@ } #endif +#ifdef CONFIG_PREEMPT_RT_FULL +static inline bool cur_pf_disabled(void) { return current->pagefault_disabled; } +#else +static inline bool cur_pf_disabled(void) { return false; } +#endif + +static inline bool pagefault_disabled(void) +{ + return in_atomic() || cur_pf_disabled(); +} + static inline struct pid *task_pid(struct task_struct *task) { return task->pids[PIDTYPE_PID].pid; @@ -1853,6 +1896,15 @@ extern void free_task(struct task_struct *tsk); #define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0) +#ifdef CONFIG_PREEMPT_RT_BASE +extern void __put_task_struct_cb(struct rcu_head *rhp); + +static inline void put_task_struct(struct task_struct *t) +{ + if (atomic_dec_and_test(&t->usage)) + call_rcu(&t->put_rcu, __put_task_struct_cb); +} +#else extern void __put_task_struct(struct task_struct *t); static inline void put_task_struct(struct task_struct *t) @@ -1860,6 +1912,7 @@ if (atomic_dec_and_test(&t->usage)) __put_task_struct(t); } +#endif #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN extern void task_cputime(struct task_struct *t, @@ -1898,6 +1951,7 @@ /* * Per process flags */ +#define PF_IN_SOFTIRQ 0x00000001 /* Task is serving softirq */ #define PF_EXITING 0x00000004 /* getting shut down */ #define PF_EXITPIDONE 0x00000008 /* pi exit done on shut down */ #define PF_VCPU 0x00000010 /* I'm a virtual CPU */ @@ -2058,6 +2112,10 @@ extern int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask); +int migrate_me(void); +void tell_sched_cpu_down_begin(int cpu); +void tell_sched_cpu_down_done(int cpu); + #else static inline void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask) @@ -2070,6 +2128,9 @@ return -EINVAL; return 0; } +static inline int migrate_me(void) { return 0; } +static inline void tell_sched_cpu_down_begin(int cpu) { } +static inline void tell_sched_cpu_down_done(int cpu) { } #endif #ifdef CONFIG_NO_HZ_COMMON @@ -2290,6 +2351,7 @@ extern int wake_up_state(struct task_struct *tsk, unsigned int state); extern int wake_up_process(struct task_struct *tsk); +extern int wake_up_lock_sleeper(struct task_struct * tsk); extern void wake_up_new_task(struct task_struct *tsk); #ifdef CONFIG_SMP extern void kick_process(struct task_struct *tsk); @@ -2406,12 +2468,24 @@ /* mmdrop drops the mm and the page tables */ extern void __mmdrop(struct mm_struct *); + static inline void mmdrop(struct mm_struct * mm) { if (unlikely(atomic_dec_and_test(&mm->mm_count))) __mmdrop(mm); } +#ifdef CONFIG_PREEMPT_RT_BASE +extern void __mmdrop_delayed(struct rcu_head *rhp); +static inline void mmdrop_delayed(struct mm_struct *mm) +{ + if (atomic_dec_and_test(&mm->mm_count)) + call_rcu(&mm->delayed_drop, __mmdrop_delayed); +} +#else +# define mmdrop_delayed(mm) mmdrop(mm) +#endif + /* mmput gets rid of the mappings and all user-space */ extern void mmput(struct mm_struct *); /* Grab a reference to a task's mm, if it is not already going away */ @@ -2719,6 +2793,43 @@ return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED)); } +#ifdef CONFIG_PREEMPT_LAZY +static inline void set_tsk_need_resched_lazy(struct task_struct *tsk) +{ + set_tsk_thread_flag(tsk,TIF_NEED_RESCHED_LAZY); +} + +static inline void clear_tsk_need_resched_lazy(struct task_struct *tsk) +{ + clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED_LAZY); +} + +static inline int test_tsk_need_resched_lazy(struct task_struct *tsk) +{ + return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED_LAZY)); +} + +static inline int need_resched_lazy(void) +{ + return test_thread_flag(TIF_NEED_RESCHED_LAZY); +} + +static inline int need_resched_now(void) +{ + return test_thread_flag(TIF_NEED_RESCHED); +} + +#else +static inline void clear_tsk_need_resched_lazy(struct task_struct *tsk) { } +static inline int need_resched_lazy(void) { return 0; } + +static inline int need_resched_now(void) +{ + return test_thread_flag(TIF_NEED_RESCHED); +} + +#endif + static inline int restart_syscall(void) { set_tsk_thread_flag(current, TIF_SIGPENDING); @@ -2750,6 +2861,51 @@ return (state & TASK_INTERRUPTIBLE) || __fatal_signal_pending(p); } +static inline bool __task_is_stopped_or_traced(struct task_struct *task) +{ + if (task->state & (__TASK_STOPPED | __TASK_TRACED)) + return true; +#ifdef CONFIG_PREEMPT_RT_FULL + if (task->saved_state & (__TASK_STOPPED | __TASK_TRACED)) + return true; +#endif + return false; +} + +static inline bool task_is_stopped_or_traced(struct task_struct *task) +{ + bool traced_stopped; + +#ifdef CONFIG_PREEMPT_RT_FULL + unsigned long flags; + + raw_spin_lock_irqsave(&task->pi_lock, flags); + traced_stopped = __task_is_stopped_or_traced(task); + raw_spin_unlock_irqrestore(&task->pi_lock, flags); +#else + traced_stopped = __task_is_stopped_or_traced(task); +#endif + return traced_stopped; +} + +static inline bool task_is_traced(struct task_struct *task) +{ + bool traced = false; + + if (task->state & __TASK_TRACED) + return true; +#ifdef CONFIG_PREEMPT_RT_FULL + /* in case the task is sleeping on tasklist_lock */ + raw_spin_lock_irq(&task->pi_lock); + if (task->state & __TASK_TRACED) + traced = true; + else if (task->saved_state & __TASK_TRACED) + traced = true; + raw_spin_unlock_irq(&task->pi_lock); +#endif + return traced; +} + /* * cond_resched() and cond_resched_lock(): latency reduction via * explicit rescheduling in places that are safe. The return @@ -2766,7 +2922,7 @@ extern int __cond_resched_lock(spinlock_t *lock); -#ifdef CONFIG_PREEMPT_COUNT +#if defined(CONFIG_PREEMPT_COUNT) && !defined(CONFIG_PREEMPT_RT_FULL) #define PREEMPT_LOCK_OFFSET PREEMPT_OFFSET #else #define PREEMPT_LOCK_OFFSET 0 @@ -2777,12 +2933,16 @@ __cond_resched_lock(lock); \ }) +#ifndef CONFIG_PREEMPT_RT_FULL extern int __cond_resched_softirq(void); #define cond_resched_softirq() ({ \ __might_sleep(__FILE__, __LINE__, SOFTIRQ_DISABLE_OFFSET); \ __cond_resched_softirq(); \ }) +#else +# define cond_resched_softirq() cond_resched() +#endif static inline void cond_resched_rcu(void) { @@ -2949,6 +3109,26 @@ #endif /* CONFIG_SMP */ +static inline int __migrate_disabled(struct task_struct *p) +{ +#ifdef CONFIG_PREEMPT_RT_FULL + return p->migrate_disable; +#else + return 0; +#endif +} + +/* Future-safe accessor for struct task_struct's cpus_allowed. */ +static inline const struct cpumask *tsk_cpus_allowed(struct task_struct *p) +{ +#ifdef CONFIG_PREEMPT_RT_FULL + if (p->migrate_disable) + return cpumask_of(task_cpu(p)); +#endif + + return &p->cpus_allowed; +} + extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask); extern long sched_getaffinity(pid_t pid, struct cpumask *mask); diff -Nur linux-3.18.14.orig/include/linux/seqlock.h linux-3.18.14-rt/include/linux/seqlock.h --- linux-3.18.14.orig/include/linux/seqlock.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/seqlock.h 2015-05-31 15:32:48.381635367 -0500 @@ -219,20 +219,30 @@ return __read_seqcount_retry(s, start); } - - -static inline void raw_write_seqcount_begin(seqcount_t *s) +static inline void __raw_write_seqcount_begin(seqcount_t *s) { s->sequence++; smp_wmb(); } -static inline void raw_write_seqcount_end(seqcount_t *s) +static inline void raw_write_seqcount_begin(seqcount_t *s) +{ + preempt_disable_rt(); + __raw_write_seqcount_begin(s); +} + +static inline void __raw_write_seqcount_end(seqcount_t *s) { smp_wmb(); s->sequence++; } +static inline void raw_write_seqcount_end(seqcount_t *s) +{ + __raw_write_seqcount_end(s); + preempt_enable_rt(); +} + /* * raw_write_seqcount_latch - redirect readers to even/odd copy * @s: pointer to seqcount_t @@ -305,10 +315,32 @@ /* * Read side functions for starting and finalizing a read side section. */ +#ifndef CONFIG_PREEMPT_RT_FULL static inline unsigned read_seqbegin(const seqlock_t *sl) { return read_seqcount_begin(&sl->seqcount); } +#else +/* + * Starvation safe read side for RT + */ +static inline unsigned read_seqbegin(seqlock_t *sl) +{ + unsigned ret; + +repeat: + ret = ACCESS_ONCE(sl->seqcount.sequence); + if (unlikely(ret & 1)) { + /* + * Take the lock and let the writer proceed (i.e. evtl + * boost it), otherwise we could loop here forever. + */ + spin_unlock_wait(&sl->lock); + goto repeat; + } + return ret; +} +#endif static inline unsigned read_seqretry(const seqlock_t *sl, unsigned start) { @@ -323,36 +355,36 @@ static inline void write_seqlock(seqlock_t *sl) { spin_lock(&sl->lock); - write_seqcount_begin(&sl->seqcount); + __raw_write_seqcount_begin(&sl->seqcount); } static inline void write_sequnlock(seqlock_t *sl) { - write_seqcount_end(&sl->seqcount); + __raw_write_seqcount_end(&sl->seqcount); spin_unlock(&sl->lock); } static inline void write_seqlock_bh(seqlock_t *sl) { spin_lock_bh(&sl->lock); - write_seqcount_begin(&sl->seqcount); + __raw_write_seqcount_begin(&sl->seqcount); } static inline void write_sequnlock_bh(seqlock_t *sl) { - write_seqcount_end(&sl->seqcount); + __raw_write_seqcount_end(&sl->seqcount); spin_unlock_bh(&sl->lock); } static inline void write_seqlock_irq(seqlock_t *sl) { spin_lock_irq(&sl->lock); - write_seqcount_begin(&sl->seqcount); + __raw_write_seqcount_begin(&sl->seqcount); } static inline void write_sequnlock_irq(seqlock_t *sl) { - write_seqcount_end(&sl->seqcount); + __raw_write_seqcount_end(&sl->seqcount); spin_unlock_irq(&sl->lock); } @@ -361,7 +393,7 @@ unsigned long flags; spin_lock_irqsave(&sl->lock, flags); - write_seqcount_begin(&sl->seqcount); + __raw_write_seqcount_begin(&sl->seqcount); return flags; } @@ -371,7 +403,7 @@ static inline void write_sequnlock_irqrestore(seqlock_t *sl, unsigned long flags) { - write_seqcount_end(&sl->seqcount); + __raw_write_seqcount_end(&sl->seqcount); spin_unlock_irqrestore(&sl->lock, flags); } diff -Nur linux-3.18.14.orig/include/linux/signal.h linux-3.18.14-rt/include/linux/signal.h --- linux-3.18.14.orig/include/linux/signal.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/signal.h 2015-05-31 15:32:48.381635367 -0500 @@ -218,6 +218,7 @@ } extern void flush_sigqueue(struct sigpending *queue); +extern void flush_task_sigqueue(struct task_struct *tsk); /* Test if 'sig' is valid signal. Use this instead of testing _NSIG directly */ static inline int valid_signal(unsigned long sig) diff -Nur linux-3.18.14.orig/include/linux/skbuff.h linux-3.18.14-rt/include/linux/skbuff.h --- linux-3.18.14.orig/include/linux/skbuff.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/skbuff.h 2015-05-31 15:32:48.405635367 -0500 @@ -172,6 +172,7 @@ __u32 qlen; spinlock_t lock; + raw_spinlock_t raw_lock; }; struct sk_buff; @@ -1328,6 +1329,12 @@ __skb_queue_head_init(list); } +static inline void skb_queue_head_init_raw(struct sk_buff_head *list) +{ + raw_spin_lock_init(&list->raw_lock); + __skb_queue_head_init(list); +} + static inline void skb_queue_head_init_class(struct sk_buff_head *list, struct lock_class_key *class) { diff -Nur linux-3.18.14.orig/include/linux/skbuff.h.orig linux-3.18.14-rt/include/linux/skbuff.h.orig --- linux-3.18.14.orig/include/linux/skbuff.h.orig 1969-12-31 18:00:00.000000000 -0600 +++ linux-3.18.14-rt/include/linux/skbuff.h.orig 2015-05-20 10:04:50.000000000 -0500 @@ -0,0 +1,3364 @@ +/* + * Definitions for the 'struct sk_buff' memory handlers. + * + * Authors: + * Alan Cox, + * Florian La Roche, + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ + +#ifndef _LINUX_SKBUFF_H +#define _LINUX_SKBUFF_H + +#include +#include +#include +#include +#include +#include + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +/* A. Checksumming of received packets by device. + * + * CHECKSUM_NONE: + * + * Device failed to checksum this packet e.g. due to lack of capabilities. + * The packet contains full (though not verified) checksum in packet but + * not in skb->csum. Thus, skb->csum is undefined in this case. + * + * CHECKSUM_UNNECESSARY: + * + * The hardware you're dealing with doesn't calculate the full checksum + * (as in CHECKSUM_COMPLETE), but it does parse headers and verify checksums + * for specific protocols. For such packets it will set CHECKSUM_UNNECESSARY + * if their checksums are okay. skb->csum is still undefined in this case + * though. It is a bad option, but, unfortunately, nowadays most vendors do + * this. Apparently with the secret goal to sell you new devices, when you + * will add new protocol to your host, f.e. IPv6 8) + * + * CHECKSUM_UNNECESSARY is applicable to following protocols: + * TCP: IPv6 and IPv4. + * UDP: IPv4 and IPv6. A device may apply CHECKSUM_UNNECESSARY to a + * zero UDP checksum for either IPv4 or IPv6, the networking stack + * may perform further validation in this case. + * GRE: only if the checksum is present in the header. + * SCTP: indicates the CRC in SCTP header has been validated. + * + * skb->csum_level indicates the number of consecutive checksums found in + * the packet minus one that have been verified as CHECKSUM_UNNECESSARY. + * For instance if a device receives an IPv6->UDP->GRE->IPv4->TCP packet + * and a device is able to verify the checksums for UDP (possibly zero), + * GRE (checksum flag is set), and TCP-- skb->csum_level would be set to + * two. If the device were only able to verify the UDP checksum and not + * GRE, either because it doesn't support GRE checksum of because GRE + * checksum is bad, skb->csum_level would be set to zero (TCP checksum is + * not considered in this case). + * + * CHECKSUM_COMPLETE: + * + * This is the most generic way. The device supplied checksum of the _whole_ + * packet as seen by netif_rx() and fills out in skb->csum. Meaning, the + * hardware doesn't need to parse L3/L4 headers to implement this. + * + * Note: Even if device supports only some protocols, but is able to produce + * skb->csum, it MUST use CHECKSUM_COMPLETE, not CHECKSUM_UNNECESSARY. + * + * CHECKSUM_PARTIAL: + * + * This is identical to the case for output below. This may occur on a packet + * received directly from another Linux OS, e.g., a virtualized Linux kernel + * on the same host. The packet can be treated in the same way as + * CHECKSUM_UNNECESSARY, except that on output (i.e., forwarding) the + * checksum must be filled in by the OS or the hardware. + * + * B. Checksumming on output. + * + * CHECKSUM_NONE: + * + * The skb was already checksummed by the protocol, or a checksum is not + * required. + * + * CHECKSUM_PARTIAL: + * + * The device is required to checksum the packet as seen by hard_start_xmit() + * from skb->csum_start up to the end, and to record/write the checksum at + * offset skb->csum_start + skb->csum_offset. + * + * The device must show its capabilities in dev->features, set up at device + * setup time, e.g. netdev_features.h: + * + * NETIF_F_HW_CSUM - It's a clever device, it's able to checksum everything. + * NETIF_F_IP_CSUM - Device is dumb, it's able to checksum only TCP/UDP over + * IPv4. Sigh. Vendors like this way for an unknown reason. + * Though, see comment above about CHECKSUM_UNNECESSARY. 8) + * NETIF_F_IPV6_CSUM - About as dumb as the last one but does IPv6 instead. + * NETIF_F_... - Well, you get the picture. + * + * CHECKSUM_UNNECESSARY: + * + * Normally, the device will do per protocol specific checksumming. Protocol + * implementations that do not want the NIC to perform the checksum + * calculation should use this flag in their outgoing skbs. + * + * NETIF_F_FCOE_CRC - This indicates that the device can do FCoE FC CRC + * offload. Correspondingly, the FCoE protocol driver + * stack should use CHECKSUM_UNNECESSARY. + * + * Any questions? No questions, good. --ANK + */ + +/* Don't change this without changing skb_csum_unnecessary! */ +#define CHECKSUM_NONE 0 +#define CHECKSUM_UNNECESSARY 1 +#define CHECKSUM_COMPLETE 2 +#define CHECKSUM_PARTIAL 3 + +/* Maximum value in skb->csum_level */ +#define SKB_MAX_CSUM_LEVEL 3 + +#define SKB_DATA_ALIGN(X) ALIGN(X, SMP_CACHE_BYTES) +#define SKB_WITH_OVERHEAD(X) \ + ((X) - SKB_DATA_ALIGN(sizeof(struct skb_shared_info))) +#define SKB_MAX_ORDER(X, ORDER) \ + SKB_WITH_OVERHEAD((PAGE_SIZE << (ORDER)) - (X)) +#define SKB_MAX_HEAD(X) (SKB_MAX_ORDER((X), 0)) +#define SKB_MAX_ALLOC (SKB_MAX_ORDER(0, 2)) + +/* return minimum truesize of one skb containing X bytes of data */ +#define SKB_TRUESIZE(X) ((X) + \ + SKB_DATA_ALIGN(sizeof(struct sk_buff)) + \ + SKB_DATA_ALIGN(sizeof(struct skb_shared_info))) + +struct net_device; +struct scatterlist; +struct pipe_inode_info; + +#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) +struct nf_conntrack { + atomic_t use; +}; +#endif + +#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER) +struct nf_bridge_info { + atomic_t use; + unsigned int mask; + struct net_device *physindev; + struct net_device *physoutdev; + unsigned long data[32 / sizeof(unsigned long)]; +}; +#endif + +struct sk_buff_head { + /* These two members must be first. */ + struct sk_buff *next; + struct sk_buff *prev; + + __u32 qlen; + spinlock_t lock; +}; + +struct sk_buff; + +/* To allow 64K frame to be packed as single skb without frag_list we + * require 64K/PAGE_SIZE pages plus 1 additional page to allow for + * buffers which do not start on a page boundary. + * + * Since GRO uses frags we allocate at least 16 regardless of page + * size. + */ +#if (65536/PAGE_SIZE + 1) < 16 +#define MAX_SKB_FRAGS 16UL +#else +#define MAX_SKB_FRAGS (65536/PAGE_SIZE + 1) +#endif + +typedef struct skb_frag_struct skb_frag_t; + +struct skb_frag_struct { + struct { + struct page *p; + } page; +#if (BITS_PER_LONG > 32) || (PAGE_SIZE >= 65536) + __u32 page_offset; + __u32 size; +#else + __u16 page_offset; + __u16 size; +#endif +}; + +static inline unsigned int skb_frag_size(const skb_frag_t *frag) +{ + return frag->size; +} + +static inline void skb_frag_size_set(skb_frag_t *frag, unsigned int size) +{ + frag->size = size; +} + +static inline void skb_frag_size_add(skb_frag_t *frag, int delta) +{ + frag->size += delta; +} + +static inline void skb_frag_size_sub(skb_frag_t *frag, int delta) +{ + frag->size -= delta; +} + +#define HAVE_HW_TIME_STAMP + +/** + * struct skb_shared_hwtstamps - hardware time stamps + * @hwtstamp: hardware time stamp transformed into duration + * since arbitrary point in time + * + * Software time stamps generated by ktime_get_real() are stored in + * skb->tstamp. + * + * hwtstamps can only be compared against other hwtstamps from + * the same device. + * + * This structure is attached to packets as part of the + * &skb_shared_info. Use skb_hwtstamps() to get a pointer. + */ +struct skb_shared_hwtstamps { + ktime_t hwtstamp; +}; + +/* Definitions for tx_flags in struct skb_shared_info */ +enum { + /* generate hardware time stamp */ + SKBTX_HW_TSTAMP = 1 << 0, + + /* generate software time stamp when queueing packet to NIC */ + SKBTX_SW_TSTAMP = 1 << 1, + + /* device driver is going to provide hardware time stamp */ + SKBTX_IN_PROGRESS = 1 << 2, + + /* device driver supports TX zero-copy buffers */ + SKBTX_DEV_ZEROCOPY = 1 << 3, + + /* generate wifi status information (where possible) */ + SKBTX_WIFI_STATUS = 1 << 4, + + /* This indicates at least one fragment might be overwritten + * (as in vmsplice(), sendfile() ...) + * If we need to compute a TX checksum, we'll need to copy + * all frags to avoid possible bad checksum + */ + SKBTX_SHARED_FRAG = 1 << 5, + + /* generate software time stamp when entering packet scheduling */ + SKBTX_SCHED_TSTAMP = 1 << 6, + + /* generate software timestamp on peer data acknowledgment */ + SKBTX_ACK_TSTAMP = 1 << 7, +}; + +#define SKBTX_ANY_SW_TSTAMP (SKBTX_SW_TSTAMP | \ + SKBTX_SCHED_TSTAMP | \ + SKBTX_ACK_TSTAMP) +#define SKBTX_ANY_TSTAMP (SKBTX_HW_TSTAMP | SKBTX_ANY_SW_TSTAMP) + +/* + * The callback notifies userspace to release buffers when skb DMA is done in + * lower device, the skb last reference should be 0 when calling this. + * The zerocopy_success argument is true if zero copy transmit occurred, + * false on data copy or out of memory error caused by data copy attempt. + * The ctx field is used to track device context. + * The desc field is used to track userspace buffer index. + */ +struct ubuf_info { + void (*callback)(struct ubuf_info *, bool zerocopy_success); + void *ctx; + unsigned long desc; +}; + +/* This data is invariant across clones and lives at + * the end of the header data, ie. at skb->end. + */ +struct skb_shared_info { + unsigned char nr_frags; + __u8 tx_flags; + unsigned short gso_size; + /* Warning: this field is not always filled in (UFO)! */ + unsigned short gso_segs; + unsigned short gso_type; + struct sk_buff *frag_list; + struct skb_shared_hwtstamps hwtstamps; + u32 tskey; + __be32 ip6_frag_id; + + /* + * Warning : all fields before dataref are cleared in __alloc_skb() + */ + atomic_t dataref; + + /* Intermediate layers must ensure that destructor_arg + * remains valid until skb destructor */ + void * destructor_arg; + + /* must be last field, see pskb_expand_head() */ + skb_frag_t frags[MAX_SKB_FRAGS]; +}; + +/* We divide dataref into two halves. The higher 16 bits hold references + * to the payload part of skb->data. The lower 16 bits hold references to + * the entire skb->data. A clone of a headerless skb holds the length of + * the header in skb->hdr_len. + * + * All users must obey the rule that the skb->data reference count must be + * greater than or equal to the payload reference count. + * + * Holding a reference to the payload part means that the user does not + * care about modifications to the header part of skb->data. + */ +#define SKB_DATAREF_SHIFT 16 +#define SKB_DATAREF_MASK ((1 << SKB_DATAREF_SHIFT) - 1) + + +enum { + SKB_FCLONE_UNAVAILABLE, /* skb has no fclone (from head_cache) */ + SKB_FCLONE_ORIG, /* orig skb (from fclone_cache) */ + SKB_FCLONE_CLONE, /* companion fclone skb (from fclone_cache) */ + SKB_FCLONE_FREE, /* this companion fclone skb is available */ +}; + +enum { + SKB_GSO_TCPV4 = 1 << 0, + SKB_GSO_UDP = 1 << 1, + + /* This indicates the skb is from an untrusted source. */ + SKB_GSO_DODGY = 1 << 2, + + /* This indicates the tcp segment has CWR set. */ + SKB_GSO_TCP_ECN = 1 << 3, + + SKB_GSO_TCPV6 = 1 << 4, + + SKB_GSO_FCOE = 1 << 5, + + SKB_GSO_GRE = 1 << 6, + + SKB_GSO_GRE_CSUM = 1 << 7, + + SKB_GSO_IPIP = 1 << 8, + + SKB_GSO_SIT = 1 << 9, + + SKB_GSO_UDP_TUNNEL = 1 << 10, + + SKB_GSO_UDP_TUNNEL_CSUM = 1 << 11, + + SKB_GSO_MPLS = 1 << 12, + +}; + +#if BITS_PER_LONG > 32 +#define NET_SKBUFF_DATA_USES_OFFSET 1 +#endif + +#ifdef NET_SKBUFF_DATA_USES_OFFSET +typedef unsigned int sk_buff_data_t; +#else +typedef unsigned char *sk_buff_data_t; +#endif + +/** + * struct skb_mstamp - multi resolution time stamps + * @stamp_us: timestamp in us resolution + * @stamp_jiffies: timestamp in jiffies + */ +struct skb_mstamp { + union { + u64 v64; + struct { + u32 stamp_us; + u32 stamp_jiffies; + }; + }; +}; + +/** + * skb_mstamp_get - get current timestamp + * @cl: place to store timestamps + */ +static inline void skb_mstamp_get(struct skb_mstamp *cl) +{ + u64 val = local_clock(); + + do_div(val, NSEC_PER_USEC); + cl->stamp_us = (u32)val; + cl->stamp_jiffies = (u32)jiffies; +} + +/** + * skb_mstamp_delta - compute the difference in usec between two skb_mstamp + * @t1: pointer to newest sample + * @t0: pointer to oldest sample + */ +static inline u32 skb_mstamp_us_delta(const struct skb_mstamp *t1, + const struct skb_mstamp *t0) +{ + s32 delta_us = t1->stamp_us - t0->stamp_us; + u32 delta_jiffies = t1->stamp_jiffies - t0->stamp_jiffies; + + /* If delta_us is negative, this might be because interval is too big, + * or local_clock() drift is too big : fallback using jiffies. + */ + if (delta_us <= 0 || + delta_jiffies >= (INT_MAX / (USEC_PER_SEC / HZ))) + + delta_us = jiffies_to_usecs(delta_jiffies); + + return delta_us; +} + + +/** + * struct sk_buff - socket buffer + * @next: Next buffer in list + * @prev: Previous buffer in list + * @tstamp: Time we arrived/left + * @sk: Socket we are owned by + * @dev: Device we arrived on/are leaving by + * @cb: Control buffer. Free for use by every layer. Put private vars here + * @_skb_refdst: destination entry (with norefcount bit) + * @sp: the security path, used for xfrm + * @len: Length of actual data + * @data_len: Data length + * @mac_len: Length of link layer header + * @hdr_len: writable header length of cloned skb + * @csum: Checksum (must include start/offset pair) + * @csum_start: Offset from skb->head where checksumming should start + * @csum_offset: Offset from csum_start where checksum should be stored + * @priority: Packet queueing priority + * @ignore_df: allow local fragmentation + * @cloned: Head may be cloned (check refcnt to be sure) + * @ip_summed: Driver fed us an IP checksum + * @nohdr: Payload reference only, must not modify header + * @nfctinfo: Relationship of this skb to the connection + * @pkt_type: Packet class + * @fclone: skbuff clone status + * @ipvs_property: skbuff is owned by ipvs + * @peeked: this packet has been seen already, so stats have been + * done for it, don't do them again + * @nf_trace: netfilter packet trace flag + * @protocol: Packet protocol from driver + * @destructor: Destruct function + * @nfct: Associated connection, if any + * @nf_bridge: Saved data about a bridged frame - see br_netfilter.c + * @skb_iif: ifindex of device we arrived on + * @tc_index: Traffic control index + * @tc_verd: traffic control verdict + * @hash: the packet hash + * @queue_mapping: Queue mapping for multiqueue devices + * @xmit_more: More SKBs are pending for this queue + * @ndisc_nodetype: router type (from link layer) + * @ooo_okay: allow the mapping of a socket to a queue to be changed + * @l4_hash: indicate hash is a canonical 4-tuple hash over transport + * ports. + * @sw_hash: indicates hash was computed in software stack + * @wifi_acked_valid: wifi_acked was set + * @wifi_acked: whether frame was acked on wifi or not + * @no_fcs: Request NIC to treat last 4 bytes as Ethernet FCS + * @napi_id: id of the NAPI struct this skb came from + * @secmark: security marking + * @mark: Generic packet mark + * @dropcount: total number of sk_receive_queue overflows + * @vlan_proto: vlan encapsulation protocol + * @vlan_tci: vlan tag control information + * @inner_protocol: Protocol (encapsulation) + * @inner_transport_header: Inner transport layer header (encapsulation) + * @inner_network_header: Network layer header (encapsulation) + * @inner_mac_header: Link layer header (encapsulation) + * @transport_header: Transport layer header + * @network_header: Network layer header + * @mac_header: Link layer header + * @tail: Tail pointer + * @end: End pointer + * @head: Head of buffer + * @data: Data head pointer + * @truesize: Buffer size + * @users: User count - see {datagram,tcp}.c + */ + +struct sk_buff { + /* These two members must be first. */ + struct sk_buff *next; + struct sk_buff *prev; + + union { + ktime_t tstamp; + struct skb_mstamp skb_mstamp; + }; + + struct sock *sk; + struct net_device *dev; + + /* + * This is the control buffer. It is free to use for every + * layer. Please put your private variables there. If you + * want to keep them across layers you have to do a skb_clone() + * first. This is owned by whoever has the skb queued ATM. + */ + char cb[48] __aligned(8); + + unsigned long _skb_refdst; + void (*destructor)(struct sk_buff *skb); +#ifdef CONFIG_XFRM + struct sec_path *sp; +#endif +#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) + struct nf_conntrack *nfct; +#endif +#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER) + struct nf_bridge_info *nf_bridge; +#endif + unsigned int len, + data_len; + __u16 mac_len, + hdr_len; + + /* Following fields are _not_ copied in __copy_skb_header() + * Note that queue_mapping is here mostly to fill a hole. + */ + kmemcheck_bitfield_begin(flags1); + __u16 queue_mapping; + __u8 cloned:1, + nohdr:1, + fclone:2, + peeked:1, + head_frag:1, + xmit_more:1; + /* one bit hole */ + kmemcheck_bitfield_end(flags1); + + /* fields enclosed in headers_start/headers_end are copied + * using a single memcpy() in __copy_skb_header() + */ + /* private: */ + __u32 headers_start[0]; + /* public: */ + +/* if you move pkt_type around you also must adapt those constants */ +#ifdef __BIG_ENDIAN_BITFIELD +#define PKT_TYPE_MAX (7 << 5) +#else +#define PKT_TYPE_MAX 7 +#endif +#define PKT_TYPE_OFFSET() offsetof(struct sk_buff, __pkt_type_offset) + + __u8 __pkt_type_offset[0]; + __u8 pkt_type:3; + __u8 pfmemalloc:1; + __u8 ignore_df:1; + __u8 nfctinfo:3; + + __u8 nf_trace:1; + __u8 ip_summed:2; + __u8 ooo_okay:1; + __u8 l4_hash:1; + __u8 sw_hash:1; + __u8 wifi_acked_valid:1; + __u8 wifi_acked:1; + + __u8 no_fcs:1; + /* Indicates the inner headers are valid in the skbuff. */ + __u8 encapsulation:1; + __u8 encap_hdr_csum:1; + __u8 csum_valid:1; + __u8 csum_complete_sw:1; + __u8 csum_level:2; + __u8 csum_bad:1; + +#ifdef CONFIG_IPV6_NDISC_NODETYPE + __u8 ndisc_nodetype:2; +#endif + __u8 ipvs_property:1; + __u8 inner_protocol_type:1; + /* 4 or 6 bit hole */ + +#ifdef CONFIG_NET_SCHED + __u16 tc_index; /* traffic control index */ +#ifdef CONFIG_NET_CLS_ACT + __u16 tc_verd; /* traffic control verdict */ +#endif +#endif + + union { + __wsum csum; + struct { + __u16 csum_start; + __u16 csum_offset; + }; + }; + __u32 priority; + int skb_iif; + __u32 hash; + __be16 vlan_proto; + __u16 vlan_tci; +#ifdef CONFIG_NET_RX_BUSY_POLL + unsigned int napi_id; +#endif +#ifdef CONFIG_NETWORK_SECMARK + __u32 secmark; +#endif + union { + __u32 mark; + __u32 dropcount; + __u32 reserved_tailroom; + }; + + union { + __be16 inner_protocol; + __u8 inner_ipproto; + }; + + __u16 inner_transport_header; + __u16 inner_network_header; + __u16 inner_mac_header; + + __be16 protocol; + __u16 transport_header; + __u16 network_header; + __u16 mac_header; + + /* private: */ + __u32 headers_end[0]; + /* public: */ + + /* These elements must be at the end, see alloc_skb() for details. */ + sk_buff_data_t tail; + sk_buff_data_t end; + unsigned char *head, + *data; + unsigned int truesize; + atomic_t users; +}; + +#ifdef __KERNEL__ +/* + * Handling routines are only of interest to the kernel + */ +#include + + +#define SKB_ALLOC_FCLONE 0x01 +#define SKB_ALLOC_RX 0x02 + +/* Returns true if the skb was allocated from PFMEMALLOC reserves */ +static inline bool skb_pfmemalloc(const struct sk_buff *skb) +{ + return unlikely(skb->pfmemalloc); +} + +/* + * skb might have a dst pointer attached, refcounted or not. + * _skb_refdst low order bit is set if refcount was _not_ taken + */ +#define SKB_DST_NOREF 1UL +#define SKB_DST_PTRMASK ~(SKB_DST_NOREF) + +/** + * skb_dst - returns skb dst_entry + * @skb: buffer + * + * Returns skb dst_entry, regardless of reference taken or not. + */ +static inline struct dst_entry *skb_dst(const struct sk_buff *skb) +{ + /* If refdst was not refcounted, check we still are in a + * rcu_read_lock section + */ + WARN_ON((skb->_skb_refdst & SKB_DST_NOREF) && + !rcu_read_lock_held() && + !rcu_read_lock_bh_held()); + return (struct dst_entry *)(skb->_skb_refdst & SKB_DST_PTRMASK); +} + +/** + * skb_dst_set - sets skb dst + * @skb: buffer + * @dst: dst entry + * + * Sets skb dst, assuming a reference was taken on dst and should + * be released by skb_dst_drop() + */ +static inline void skb_dst_set(struct sk_buff *skb, struct dst_entry *dst) +{ + skb->_skb_refdst = (unsigned long)dst; +} + +void __skb_dst_set_noref(struct sk_buff *skb, struct dst_entry *dst, + bool force); + +/** + * skb_dst_set_noref - sets skb dst, hopefully, without taking reference + * @skb: buffer + * @dst: dst entry + * + * Sets skb dst, assuming a reference was not taken on dst. + * If dst entry is cached, we do not take reference and dst_release + * will be avoided by refdst_drop. If dst entry is not cached, we take + * reference, so that last dst_release can destroy the dst immediately. + */ +static inline void skb_dst_set_noref(struct sk_buff *skb, struct dst_entry *dst) +{ + __skb_dst_set_noref(skb, dst, false); +} + +/** + * skb_dst_set_noref_force - sets skb dst, without taking reference + * @skb: buffer + * @dst: dst entry + * + * Sets skb dst, assuming a reference was not taken on dst. + * No reference is taken and no dst_release will be called. While for + * cached dsts deferred reclaim is a basic feature, for entries that are + * not cached it is caller's job to guarantee that last dst_release for + * provided dst happens when nobody uses it, eg. after a RCU grace period. + */ +static inline void skb_dst_set_noref_force(struct sk_buff *skb, + struct dst_entry *dst) +{ + __skb_dst_set_noref(skb, dst, true); +} + +/** + * skb_dst_is_noref - Test if skb dst isn't refcounted + * @skb: buffer + */ +static inline bool skb_dst_is_noref(const struct sk_buff *skb) +{ + return (skb->_skb_refdst & SKB_DST_NOREF) && skb_dst(skb); +} + +static inline struct rtable *skb_rtable(const struct sk_buff *skb) +{ + return (struct rtable *)skb_dst(skb); +} + +void kfree_skb(struct sk_buff *skb); +void kfree_skb_list(struct sk_buff *segs); +void skb_tx_error(struct sk_buff *skb); +void consume_skb(struct sk_buff *skb); +void __kfree_skb(struct sk_buff *skb); +extern struct kmem_cache *skbuff_head_cache; + +void kfree_skb_partial(struct sk_buff *skb, bool head_stolen); +bool skb_try_coalesce(struct sk_buff *to, struct sk_buff *from, + bool *fragstolen, int *delta_truesize); + +struct sk_buff *__alloc_skb(unsigned int size, gfp_t priority, int flags, + int node); +struct sk_buff *__build_skb(void *data, unsigned int frag_size); +struct sk_buff *build_skb(void *data, unsigned int frag_size); +static inline struct sk_buff *alloc_skb(unsigned int size, + gfp_t priority) +{ + return __alloc_skb(size, priority, 0, NUMA_NO_NODE); +} + +struct sk_buff *alloc_skb_with_frags(unsigned long header_len, + unsigned long data_len, + int max_page_order, + int *errcode, + gfp_t gfp_mask); + +/* Layout of fast clones : [skb1][skb2][fclone_ref] */ +struct sk_buff_fclones { + struct sk_buff skb1; + + struct sk_buff skb2; + + atomic_t fclone_ref; +}; + +/** + * skb_fclone_busy - check if fclone is busy + * @skb: buffer + * + * Returns true is skb is a fast clone, and its clone is not freed. + * Some drivers call skb_orphan() in their ndo_start_xmit(), + * so we also check that this didnt happen. + */ +static inline bool skb_fclone_busy(const struct sock *sk, + const struct sk_buff *skb) +{ + const struct sk_buff_fclones *fclones; + + fclones = container_of(skb, struct sk_buff_fclones, skb1); + + return skb->fclone == SKB_FCLONE_ORIG && + fclones->skb2.fclone == SKB_FCLONE_CLONE && + fclones->skb2.sk == sk; +} + +static inline struct sk_buff *alloc_skb_fclone(unsigned int size, + gfp_t priority) +{ + return __alloc_skb(size, priority, SKB_ALLOC_FCLONE, NUMA_NO_NODE); +} + +struct sk_buff *__alloc_skb_head(gfp_t priority, int node); +static inline struct sk_buff *alloc_skb_head(gfp_t priority) +{ + return __alloc_skb_head(priority, -1); +} + +struct sk_buff *skb_morph(struct sk_buff *dst, struct sk_buff *src); +int skb_copy_ubufs(struct sk_buff *skb, gfp_t gfp_mask); +struct sk_buff *skb_clone(struct sk_buff *skb, gfp_t priority); +struct sk_buff *skb_copy(const struct sk_buff *skb, gfp_t priority); +struct sk_buff *__pskb_copy_fclone(struct sk_buff *skb, int headroom, + gfp_t gfp_mask, bool fclone); +static inline struct sk_buff *__pskb_copy(struct sk_buff *skb, int headroom, + gfp_t gfp_mask) +{ + return __pskb_copy_fclone(skb, headroom, gfp_mask, false); +} + +int pskb_expand_head(struct sk_buff *skb, int nhead, int ntail, gfp_t gfp_mask); +struct sk_buff *skb_realloc_headroom(struct sk_buff *skb, + unsigned int headroom); +struct sk_buff *skb_copy_expand(const struct sk_buff *skb, int newheadroom, + int newtailroom, gfp_t priority); +int skb_to_sgvec_nomark(struct sk_buff *skb, struct scatterlist *sg, + int offset, int len); +int skb_to_sgvec(struct sk_buff *skb, struct scatterlist *sg, int offset, + int len); +int skb_cow_data(struct sk_buff *skb, int tailbits, struct sk_buff **trailer); +int skb_pad(struct sk_buff *skb, int pad); +#define dev_kfree_skb(a) consume_skb(a) + +int skb_append_datato_frags(struct sock *sk, struct sk_buff *skb, + int getfrag(void *from, char *to, int offset, + int len, int odd, struct sk_buff *skb), + void *from, int length); + +struct skb_seq_state { + __u32 lower_offset; + __u32 upper_offset; + __u32 frag_idx; + __u32 stepped_offset; + struct sk_buff *root_skb; + struct sk_buff *cur_skb; + __u8 *frag_data; +}; + +void skb_prepare_seq_read(struct sk_buff *skb, unsigned int from, + unsigned int to, struct skb_seq_state *st); +unsigned int skb_seq_read(unsigned int consumed, const u8 **data, + struct skb_seq_state *st); +void skb_abort_seq_read(struct skb_seq_state *st); + +unsigned int skb_find_text(struct sk_buff *skb, unsigned int from, + unsigned int to, struct ts_config *config, + struct ts_state *state); + +/* + * Packet hash types specify the type of hash in skb_set_hash. + * + * Hash types refer to the protocol layer addresses which are used to + * construct a packet's hash. The hashes are used to differentiate or identify + * flows of the protocol layer for the hash type. Hash types are either + * layer-2 (L2), layer-3 (L3), or layer-4 (L4). + * + * Properties of hashes: + * + * 1) Two packets in different flows have different hash values + * 2) Two packets in the same flow should have the same hash value + * + * A hash at a higher layer is considered to be more specific. A driver should + * set the most specific hash possible. + * + * A driver cannot indicate a more specific hash than the layer at which a hash + * was computed. For instance an L3 hash cannot be set as an L4 hash. + * + * A driver may indicate a hash level which is less specific than the + * actual layer the hash was computed on. For instance, a hash computed + * at L4 may be considered an L3 hash. This should only be done if the + * driver can't unambiguously determine that the HW computed the hash at + * the higher layer. Note that the "should" in the second property above + * permits this. + */ +enum pkt_hash_types { + PKT_HASH_TYPE_NONE, /* Undefined type */ + PKT_HASH_TYPE_L2, /* Input: src_MAC, dest_MAC */ + PKT_HASH_TYPE_L3, /* Input: src_IP, dst_IP */ + PKT_HASH_TYPE_L4, /* Input: src_IP, dst_IP, src_port, dst_port */ +}; + +static inline void +skb_set_hash(struct sk_buff *skb, __u32 hash, enum pkt_hash_types type) +{ + skb->l4_hash = (type == PKT_HASH_TYPE_L4); + skb->sw_hash = 0; + skb->hash = hash; +} + +void __skb_get_hash(struct sk_buff *skb); +static inline __u32 skb_get_hash(struct sk_buff *skb) +{ + if (!skb->l4_hash && !skb->sw_hash) + __skb_get_hash(skb); + + return skb->hash; +} + +static inline __u32 skb_get_hash_raw(const struct sk_buff *skb) +{ + return skb->hash; +} + +static inline void skb_clear_hash(struct sk_buff *skb) +{ + skb->hash = 0; + skb->sw_hash = 0; + skb->l4_hash = 0; +} + +static inline void skb_clear_hash_if_not_l4(struct sk_buff *skb) +{ + if (!skb->l4_hash) + skb_clear_hash(skb); +} + +static inline void skb_copy_hash(struct sk_buff *to, const struct sk_buff *from) +{ + to->hash = from->hash; + to->sw_hash = from->sw_hash; + to->l4_hash = from->l4_hash; +}; + +#ifdef NET_SKBUFF_DATA_USES_OFFSET +static inline unsigned char *skb_end_pointer(const struct sk_buff *skb) +{ + return skb->head + skb->end; +} + +static inline unsigned int skb_end_offset(const struct sk_buff *skb) +{ + return skb->end; +} +#else +static inline unsigned char *skb_end_pointer(const struct sk_buff *skb) +{ + return skb->end; +} + +static inline unsigned int skb_end_offset(const struct sk_buff *skb) +{ + return skb->end - skb->head; +} +#endif + +/* Internal */ +#define skb_shinfo(SKB) ((struct skb_shared_info *)(skb_end_pointer(SKB))) + +static inline struct skb_shared_hwtstamps *skb_hwtstamps(struct sk_buff *skb) +{ + return &skb_shinfo(skb)->hwtstamps; +} + +/** + * skb_queue_empty - check if a queue is empty + * @list: queue head + * + * Returns true if the queue is empty, false otherwise. + */ +static inline int skb_queue_empty(const struct sk_buff_head *list) +{ + return list->next == (const struct sk_buff *) list; +} + +/** + * skb_queue_is_last - check if skb is the last entry in the queue + * @list: queue head + * @skb: buffer + * + * Returns true if @skb is the last buffer on the list. + */ +static inline bool skb_queue_is_last(const struct sk_buff_head *list, + const struct sk_buff *skb) +{ + return skb->next == (const struct sk_buff *) list; +} + +/** + * skb_queue_is_first - check if skb is the first entry in the queue + * @list: queue head + * @skb: buffer + * + * Returns true if @skb is the first buffer on the list. + */ +static inline bool skb_queue_is_first(const struct sk_buff_head *list, + const struct sk_buff *skb) +{ + return skb->prev == (const struct sk_buff *) list; +} + +/** + * skb_queue_next - return the next packet in the queue + * @list: queue head + * @skb: current buffer + * + * Return the next packet in @list after @skb. It is only valid to + * call this if skb_queue_is_last() evaluates to false. + */ +static inline struct sk_buff *skb_queue_next(const struct sk_buff_head *list, + const struct sk_buff *skb) +{ + /* This BUG_ON may seem severe, but if we just return then we + * are going to dereference garbage. + */ + BUG_ON(skb_queue_is_last(list, skb)); + return skb->next; +} + +/** + * skb_queue_prev - return the prev packet in the queue + * @list: queue head + * @skb: current buffer + * + * Return the prev packet in @list before @skb. It is only valid to + * call this if skb_queue_is_first() evaluates to false. + */ +static inline struct sk_buff *skb_queue_prev(const struct sk_buff_head *list, + const struct sk_buff *skb) +{ + /* This BUG_ON may seem severe, but if we just return then we + * are going to dereference garbage. + */ + BUG_ON(skb_queue_is_first(list, skb)); + return skb->prev; +} + +/** + * skb_get - reference buffer + * @skb: buffer to reference + * + * Makes another reference to a socket buffer and returns a pointer + * to the buffer. + */ +static inline struct sk_buff *skb_get(struct sk_buff *skb) +{ + atomic_inc(&skb->users); + return skb; +} + +/* + * If users == 1, we are the only owner and are can avoid redundant + * atomic change. + */ + +/** + * skb_cloned - is the buffer a clone + * @skb: buffer to check + * + * Returns true if the buffer was generated with skb_clone() and is + * one of multiple shared copies of the buffer. Cloned buffers are + * shared data so must not be written to under normal circumstances. + */ +static inline int skb_cloned(const struct sk_buff *skb) +{ + return skb->cloned && + (atomic_read(&skb_shinfo(skb)->dataref) & SKB_DATAREF_MASK) != 1; +} + +static inline int skb_unclone(struct sk_buff *skb, gfp_t pri) +{ + might_sleep_if(pri & __GFP_WAIT); + + if (skb_cloned(skb)) + return pskb_expand_head(skb, 0, 0, pri); + + return 0; +} + +/** + * skb_header_cloned - is the header a clone + * @skb: buffer to check + * + * Returns true if modifying the header part of the buffer requires + * the data to be copied. + */ +static inline int skb_header_cloned(const struct sk_buff *skb) +{ + int dataref; + + if (!skb->cloned) + return 0; + + dataref = atomic_read(&skb_shinfo(skb)->dataref); + dataref = (dataref & SKB_DATAREF_MASK) - (dataref >> SKB_DATAREF_SHIFT); + return dataref != 1; +} + +/** + * skb_header_release - release reference to header + * @skb: buffer to operate on + * + * Drop a reference to the header part of the buffer. This is done + * by acquiring a payload reference. You must not read from the header + * part of skb->data after this. + * Note : Check if you can use __skb_header_release() instead. + */ +static inline void skb_header_release(struct sk_buff *skb) +{ + BUG_ON(skb->nohdr); + skb->nohdr = 1; + atomic_add(1 << SKB_DATAREF_SHIFT, &skb_shinfo(skb)->dataref); +} + +/** + * __skb_header_release - release reference to header + * @skb: buffer to operate on + * + * Variant of skb_header_release() assuming skb is private to caller. + * We can avoid one atomic operation. + */ +static inline void __skb_header_release(struct sk_buff *skb) +{ + skb->nohdr = 1; + atomic_set(&skb_shinfo(skb)->dataref, 1 + (1 << SKB_DATAREF_SHIFT)); +} + + +/** + * skb_shared - is the buffer shared + * @skb: buffer to check + * + * Returns true if more than one person has a reference to this + * buffer. + */ +static inline int skb_shared(const struct sk_buff *skb) +{ + return atomic_read(&skb->users) != 1; +} + +/** + * skb_share_check - check if buffer is shared and if so clone it + * @skb: buffer to check + * @pri: priority for memory allocation + * + * If the buffer is shared the buffer is cloned and the old copy + * drops a reference. A new clone with a single reference is returned. + * If the buffer is not shared the original buffer is returned. When + * being called from interrupt status or with spinlocks held pri must + * be GFP_ATOMIC. + * + * NULL is returned on a memory allocation failure. + */ +static inline struct sk_buff *skb_share_check(struct sk_buff *skb, gfp_t pri) +{ + might_sleep_if(pri & __GFP_WAIT); + if (skb_shared(skb)) { + struct sk_buff *nskb = skb_clone(skb, pri); + + if (likely(nskb)) + consume_skb(skb); + else + kfree_skb(skb); + skb = nskb; + } + return skb; +} + +/* + * Copy shared buffers into a new sk_buff. We effectively do COW on + * packets to handle cases where we have a local reader and forward + * and a couple of other messy ones. The normal one is tcpdumping + * a packet thats being forwarded. + */ + +/** + * skb_unshare - make a copy of a shared buffer + * @skb: buffer to check + * @pri: priority for memory allocation + * + * If the socket buffer is a clone then this function creates a new + * copy of the data, drops a reference count on the old copy and returns + * the new copy with the reference count at 1. If the buffer is not a clone + * the original buffer is returned. When called with a spinlock held or + * from interrupt state @pri must be %GFP_ATOMIC + * + * %NULL is returned on a memory allocation failure. + */ +static inline struct sk_buff *skb_unshare(struct sk_buff *skb, + gfp_t pri) +{ + might_sleep_if(pri & __GFP_WAIT); + if (skb_cloned(skb)) { + struct sk_buff *nskb = skb_copy(skb, pri); + + /* Free our shared copy */ + if (likely(nskb)) + consume_skb(skb); + else + kfree_skb(skb); + skb = nskb; + } + return skb; +} + +/** + * skb_peek - peek at the head of an &sk_buff_head + * @list_: list to peek at + * + * Peek an &sk_buff. Unlike most other operations you _MUST_ + * be careful with this one. A peek leaves the buffer on the + * list and someone else may run off with it. You must hold + * the appropriate locks or have a private queue to do this. + * + * Returns %NULL for an empty list or a pointer to the head element. + * The reference count is not incremented and the reference is therefore + * volatile. Use with caution. + */ +static inline struct sk_buff *skb_peek(const struct sk_buff_head *list_) +{ + struct sk_buff *skb = list_->next; + + if (skb == (struct sk_buff *)list_) + skb = NULL; + return skb; +} + +/** + * skb_peek_next - peek skb following the given one from a queue + * @skb: skb to start from + * @list_: list to peek at + * + * Returns %NULL when the end of the list is met or a pointer to the + * next element. The reference count is not incremented and the + * reference is therefore volatile. Use with caution. + */ +static inline struct sk_buff *skb_peek_next(struct sk_buff *skb, + const struct sk_buff_head *list_) +{ + struct sk_buff *next = skb->next; + + if (next == (struct sk_buff *)list_) + next = NULL; + return next; +} + +/** + * skb_peek_tail - peek at the tail of an &sk_buff_head + * @list_: list to peek at + * + * Peek an &sk_buff. Unlike most other operations you _MUST_ + * be careful with this one. A peek leaves the buffer on the + * list and someone else may run off with it. You must hold + * the appropriate locks or have a private queue to do this. + * + * Returns %NULL for an empty list or a pointer to the tail element. + * The reference count is not incremented and the reference is therefore + * volatile. Use with caution. + */ +static inline struct sk_buff *skb_peek_tail(const struct sk_buff_head *list_) +{ + struct sk_buff *skb = list_->prev; + + if (skb == (struct sk_buff *)list_) + skb = NULL; + return skb; + +} + +/** + * skb_queue_len - get queue length + * @list_: list to measure + * + * Return the length of an &sk_buff queue. + */ +static inline __u32 skb_queue_len(const struct sk_buff_head *list_) +{ + return list_->qlen; +} + +/** + * __skb_queue_head_init - initialize non-spinlock portions of sk_buff_head + * @list: queue to initialize + * + * This initializes only the list and queue length aspects of + * an sk_buff_head object. This allows to initialize the list + * aspects of an sk_buff_head without reinitializing things like + * the spinlock. It can also be used for on-stack sk_buff_head + * objects where the spinlock is known to not be used. + */ +static inline void __skb_queue_head_init(struct sk_buff_head *list) +{ + list->prev = list->next = (struct sk_buff *)list; + list->qlen = 0; +} + +/* + * This function creates a split out lock class for each invocation; + * this is needed for now since a whole lot of users of the skb-queue + * infrastructure in drivers have different locking usage (in hardirq) + * than the networking core (in softirq only). In the long run either the + * network layer or drivers should need annotation to consolidate the + * main types of usage into 3 classes. + */ +static inline void skb_queue_head_init(struct sk_buff_head *list) +{ + spin_lock_init(&list->lock); + __skb_queue_head_init(list); +} + +static inline void skb_queue_head_init_class(struct sk_buff_head *list, + struct lock_class_key *class) +{ + skb_queue_head_init(list); + lockdep_set_class(&list->lock, class); +} + +/* + * Insert an sk_buff on a list. + * + * The "__skb_xxxx()" functions are the non-atomic ones that + * can only be called with interrupts disabled. + */ +void skb_insert(struct sk_buff *old, struct sk_buff *newsk, + struct sk_buff_head *list); +static inline void __skb_insert(struct sk_buff *newsk, + struct sk_buff *prev, struct sk_buff *next, + struct sk_buff_head *list) +{ + newsk->next = next; + newsk->prev = prev; + next->prev = prev->next = newsk; + list->qlen++; +} + +static inline void __skb_queue_splice(const struct sk_buff_head *list, + struct sk_buff *prev, + struct sk_buff *next) +{ + struct sk_buff *first = list->next; + struct sk_buff *last = list->prev; + + first->prev = prev; + prev->next = first; + + last->next = next; + next->prev = last; +} + +/** + * skb_queue_splice - join two skb lists, this is designed for stacks + * @list: the new list to add + * @head: the place to add it in the first list + */ +static inline void skb_queue_splice(const struct sk_buff_head *list, + struct sk_buff_head *head) +{ + if (!skb_queue_empty(list)) { + __skb_queue_splice(list, (struct sk_buff *) head, head->next); + head->qlen += list->qlen; + } +} + +/** + * skb_queue_splice_init - join two skb lists and reinitialise the emptied list + * @list: the new list to add + * @head: the place to add it in the first list + * + * The list at @list is reinitialised + */ +static inline void skb_queue_splice_init(struct sk_buff_head *list, + struct sk_buff_head *head) +{ + if (!skb_queue_empty(list)) { + __skb_queue_splice(list, (struct sk_buff *) head, head->next); + head->qlen += list->qlen; + __skb_queue_head_init(list); + } +} + +/** + * skb_queue_splice_tail - join two skb lists, each list being a queue + * @list: the new list to add + * @head: the place to add it in the first list + */ +static inline void skb_queue_splice_tail(const struct sk_buff_head *list, + struct sk_buff_head *head) +{ + if (!skb_queue_empty(list)) { + __skb_queue_splice(list, head->prev, (struct sk_buff *) head); + head->qlen += list->qlen; + } +} + +/** + * skb_queue_splice_tail_init - join two skb lists and reinitialise the emptied list + * @list: the new list to add + * @head: the place to add it in the first list + * + * Each of the lists is a queue. + * The list at @list is reinitialised + */ +static inline void skb_queue_splice_tail_init(struct sk_buff_head *list, + struct sk_buff_head *head) +{ + if (!skb_queue_empty(list)) { + __skb_queue_splice(list, head->prev, (struct sk_buff *) head); + head->qlen += list->qlen; + __skb_queue_head_init(list); + } +} + +/** + * __skb_queue_after - queue a buffer at the list head + * @list: list to use + * @prev: place after this buffer + * @newsk: buffer to queue + * + * Queue a buffer int the middle of a list. This function takes no locks + * and you must therefore hold required locks before calling it. + * + * A buffer cannot be placed on two lists at the same time. + */ +static inline void __skb_queue_after(struct sk_buff_head *list, + struct sk_buff *prev, + struct sk_buff *newsk) +{ + __skb_insert(newsk, prev, prev->next, list); +} + +void skb_append(struct sk_buff *old, struct sk_buff *newsk, + struct sk_buff_head *list); + +static inline void __skb_queue_before(struct sk_buff_head *list, + struct sk_buff *next, + struct sk_buff *newsk) +{ + __skb_insert(newsk, next->prev, next, list); +} + +/** + * __skb_queue_head - queue a buffer at the list head + * @list: list to use + * @newsk: buffer to queue + * + * Queue a buffer at the start of a list. This function takes no locks + * and you must therefore hold required locks before calling it. + * + * A buffer cannot be placed on two lists at the same time. + */ +void skb_queue_head(struct sk_buff_head *list, struct sk_buff *newsk); +static inline void __skb_queue_head(struct sk_buff_head *list, + struct sk_buff *newsk) +{ + __skb_queue_after(list, (struct sk_buff *)list, newsk); +} + +/** + * __skb_queue_tail - queue a buffer at the list tail + * @list: list to use + * @newsk: buffer to queue + * + * Queue a buffer at the end of a list. This function takes no locks + * and you must therefore hold required locks before calling it. + * + * A buffer cannot be placed on two lists at the same time. + */ +void skb_queue_tail(struct sk_buff_head *list, struct sk_buff *newsk); +static inline void __skb_queue_tail(struct sk_buff_head *list, + struct sk_buff *newsk) +{ + __skb_queue_before(list, (struct sk_buff *)list, newsk); +} + +/* + * remove sk_buff from list. _Must_ be called atomically, and with + * the list known.. + */ +void skb_unlink(struct sk_buff *skb, struct sk_buff_head *list); +static inline void __skb_unlink(struct sk_buff *skb, struct sk_buff_head *list) +{ + struct sk_buff *next, *prev; + + list->qlen--; + next = skb->next; + prev = skb->prev; + skb->next = skb->prev = NULL; + next->prev = prev; + prev->next = next; +} + +/** + * __skb_dequeue - remove from the head of the queue + * @list: list to dequeue from + * + * Remove the head of the list. This function does not take any locks + * so must be used with appropriate locks held only. The head item is + * returned or %NULL if the list is empty. + */ +struct sk_buff *skb_dequeue(struct sk_buff_head *list); +static inline struct sk_buff *__skb_dequeue(struct sk_buff_head *list) +{ + struct sk_buff *skb = skb_peek(list); + if (skb) + __skb_unlink(skb, list); + return skb; +} + +/** + * __skb_dequeue_tail - remove from the tail of the queue + * @list: list to dequeue from + * + * Remove the tail of the list. This function does not take any locks + * so must be used with appropriate locks held only. The tail item is + * returned or %NULL if the list is empty. + */ +struct sk_buff *skb_dequeue_tail(struct sk_buff_head *list); +static inline struct sk_buff *__skb_dequeue_tail(struct sk_buff_head *list) +{ + struct sk_buff *skb = skb_peek_tail(list); + if (skb) + __skb_unlink(skb, list); + return skb; +} + + +static inline bool skb_is_nonlinear(const struct sk_buff *skb) +{ + return skb->data_len; +} + +static inline unsigned int skb_headlen(const struct sk_buff *skb) +{ + return skb->len - skb->data_len; +} + +static inline int skb_pagelen(const struct sk_buff *skb) +{ + int i, len = 0; + + for (i = (int)skb_shinfo(skb)->nr_frags - 1; i >= 0; i--) + len += skb_frag_size(&skb_shinfo(skb)->frags[i]); + return len + skb_headlen(skb); +} + +/** + * __skb_fill_page_desc - initialise a paged fragment in an skb + * @skb: buffer containing fragment to be initialised + * @i: paged fragment index to initialise + * @page: the page to use for this fragment + * @off: the offset to the data with @page + * @size: the length of the data + * + * Initialises the @i'th fragment of @skb to point to &size bytes at + * offset @off within @page. + * + * Does not take any additional reference on the fragment. + */ +static inline void __skb_fill_page_desc(struct sk_buff *skb, int i, + struct page *page, int off, int size) +{ + skb_frag_t *frag = &skb_shinfo(skb)->frags[i]; + + /* + * Propagate page->pfmemalloc to the skb if we can. The problem is + * that not all callers have unique ownership of the page. If + * pfmemalloc is set, we check the mapping as a mapping implies + * page->index is set (index and pfmemalloc share space). + * If it's a valid mapping, we cannot use page->pfmemalloc but we + * do not lose pfmemalloc information as the pages would not be + * allocated using __GFP_MEMALLOC. + */ + frag->page.p = page; + frag->page_offset = off; + skb_frag_size_set(frag, size); + + page = compound_head(page); + if (page->pfmemalloc && !page->mapping) + skb->pfmemalloc = true; +} + +/** + * skb_fill_page_desc - initialise a paged fragment in an skb + * @skb: buffer containing fragment to be initialised + * @i: paged fragment index to initialise + * @page: the page to use for this fragment + * @off: the offset to the data with @page + * @size: the length of the data + * + * As per __skb_fill_page_desc() -- initialises the @i'th fragment of + * @skb to point to @size bytes at offset @off within @page. In + * addition updates @skb such that @i is the last fragment. + * + * Does not take any additional reference on the fragment. + */ +static inline void skb_fill_page_desc(struct sk_buff *skb, int i, + struct page *page, int off, int size) +{ + __skb_fill_page_desc(skb, i, page, off, size); + skb_shinfo(skb)->nr_frags = i + 1; +} + +void skb_add_rx_frag(struct sk_buff *skb, int i, struct page *page, int off, + int size, unsigned int truesize); + +void skb_coalesce_rx_frag(struct sk_buff *skb, int i, int size, + unsigned int truesize); + +#define SKB_PAGE_ASSERT(skb) BUG_ON(skb_shinfo(skb)->nr_frags) +#define SKB_FRAG_ASSERT(skb) BUG_ON(skb_has_frag_list(skb)) +#define SKB_LINEAR_ASSERT(skb) BUG_ON(skb_is_nonlinear(skb)) + +#ifdef NET_SKBUFF_DATA_USES_OFFSET +static inline unsigned char *skb_tail_pointer(const struct sk_buff *skb) +{ + return skb->head + skb->tail; +} + +static inline void skb_reset_tail_pointer(struct sk_buff *skb) +{ + skb->tail = skb->data - skb->head; +} + +static inline void skb_set_tail_pointer(struct sk_buff *skb, const int offset) +{ + skb_reset_tail_pointer(skb); + skb->tail += offset; +} + +#else /* NET_SKBUFF_DATA_USES_OFFSET */ +static inline unsigned char *skb_tail_pointer(const struct sk_buff *skb) +{ + return skb->tail; +} + +static inline void skb_reset_tail_pointer(struct sk_buff *skb) +{ + skb->tail = skb->data; +} + +static inline void skb_set_tail_pointer(struct sk_buff *skb, const int offset) +{ + skb->tail = skb->data + offset; +} + +#endif /* NET_SKBUFF_DATA_USES_OFFSET */ + +/* + * Add data to an sk_buff + */ +unsigned char *pskb_put(struct sk_buff *skb, struct sk_buff *tail, int len); +unsigned char *skb_put(struct sk_buff *skb, unsigned int len); +static inline unsigned char *__skb_put(struct sk_buff *skb, unsigned int len) +{ + unsigned char *tmp = skb_tail_pointer(skb); + SKB_LINEAR_ASSERT(skb); + skb->tail += len; + skb->len += len; + return tmp; +} + +unsigned char *skb_push(struct sk_buff *skb, unsigned int len); +static inline unsigned char *__skb_push(struct sk_buff *skb, unsigned int len) +{ + skb->data -= len; + skb->len += len; + return skb->data; +} + +unsigned char *skb_pull(struct sk_buff *skb, unsigned int len); +static inline unsigned char *__skb_pull(struct sk_buff *skb, unsigned int len) +{ + skb->len -= len; + BUG_ON(skb->len < skb->data_len); + return skb->data += len; +} + +static inline unsigned char *skb_pull_inline(struct sk_buff *skb, unsigned int len) +{ + return unlikely(len > skb->len) ? NULL : __skb_pull(skb, len); +} + +unsigned char *__pskb_pull_tail(struct sk_buff *skb, int delta); + +static inline unsigned char *__pskb_pull(struct sk_buff *skb, unsigned int len) +{ + if (len > skb_headlen(skb) && + !__pskb_pull_tail(skb, len - skb_headlen(skb))) + return NULL; + skb->len -= len; + return skb->data += len; +} + +static inline unsigned char *pskb_pull(struct sk_buff *skb, unsigned int len) +{ + return unlikely(len > skb->len) ? NULL : __pskb_pull(skb, len); +} + +static inline int pskb_may_pull(struct sk_buff *skb, unsigned int len) +{ + if (likely(len <= skb_headlen(skb))) + return 1; + if (unlikely(len > skb->len)) + return 0; + return __pskb_pull_tail(skb, len - skb_headlen(skb)) != NULL; +} + +/** + * skb_headroom - bytes at buffer head + * @skb: buffer to check + * + * Return the number of bytes of free space at the head of an &sk_buff. + */ +static inline unsigned int skb_headroom(const struct sk_buff *skb) +{ + return skb->data - skb->head; +} + +/** + * skb_tailroom - bytes at buffer end + * @skb: buffer to check + * + * Return the number of bytes of free space at the tail of an sk_buff + */ +static inline int skb_tailroom(const struct sk_buff *skb) +{ + return skb_is_nonlinear(skb) ? 0 : skb->end - skb->tail; +} + +/** + * skb_availroom - bytes at buffer end + * @skb: buffer to check + * + * Return the number of bytes of free space at the tail of an sk_buff + * allocated by sk_stream_alloc() + */ +static inline int skb_availroom(const struct sk_buff *skb) +{ + if (skb_is_nonlinear(skb)) + return 0; + + return skb->end - skb->tail - skb->reserved_tailroom; +} + +/** + * skb_reserve - adjust headroom + * @skb: buffer to alter + * @len: bytes to move + * + * Increase the headroom of an empty &sk_buff by reducing the tail + * room. This is only allowed for an empty buffer. + */ +static inline void skb_reserve(struct sk_buff *skb, int len) +{ + skb->data += len; + skb->tail += len; +} + +#define ENCAP_TYPE_ETHER 0 +#define ENCAP_TYPE_IPPROTO 1 + +static inline void skb_set_inner_protocol(struct sk_buff *skb, + __be16 protocol) +{ + skb->inner_protocol = protocol; + skb->inner_protocol_type = ENCAP_TYPE_ETHER; +} + +static inline void skb_set_inner_ipproto(struct sk_buff *skb, + __u8 ipproto) +{ + skb->inner_ipproto = ipproto; + skb->inner_protocol_type = ENCAP_TYPE_IPPROTO; +} + +static inline void skb_reset_inner_headers(struct sk_buff *skb) +{ + skb->inner_mac_header = skb->mac_header; + skb->inner_network_header = skb->network_header; + skb->inner_transport_header = skb->transport_header; +} + +static inline void skb_reset_mac_len(struct sk_buff *skb) +{ + skb->mac_len = skb->network_header - skb->mac_header; +} + +static inline unsigned char *skb_inner_transport_header(const struct sk_buff + *skb) +{ + return skb->head + skb->inner_transport_header; +} + +static inline void skb_reset_inner_transport_header(struct sk_buff *skb) +{ + skb->inner_transport_header = skb->data - skb->head; +} + +static inline void skb_set_inner_transport_header(struct sk_buff *skb, + const int offset) +{ + skb_reset_inner_transport_header(skb); + skb->inner_transport_header += offset; +} + +static inline unsigned char *skb_inner_network_header(const struct sk_buff *skb) +{ + return skb->head + skb->inner_network_header; +} + +static inline void skb_reset_inner_network_header(struct sk_buff *skb) +{ + skb->inner_network_header = skb->data - skb->head; +} + +static inline void skb_set_inner_network_header(struct sk_buff *skb, + const int offset) +{ + skb_reset_inner_network_header(skb); + skb->inner_network_header += offset; +} + +static inline unsigned char *skb_inner_mac_header(const struct sk_buff *skb) +{ + return skb->head + skb->inner_mac_header; +} + +static inline void skb_reset_inner_mac_header(struct sk_buff *skb) +{ + skb->inner_mac_header = skb->data - skb->head; +} + +static inline void skb_set_inner_mac_header(struct sk_buff *skb, + const int offset) +{ + skb_reset_inner_mac_header(skb); + skb->inner_mac_header += offset; +} +static inline bool skb_transport_header_was_set(const struct sk_buff *skb) +{ + return skb->transport_header != (typeof(skb->transport_header))~0U; +} + +static inline unsigned char *skb_transport_header(const struct sk_buff *skb) +{ + return skb->head + skb->transport_header; +} + +static inline void skb_reset_transport_header(struct sk_buff *skb) +{ + skb->transport_header = skb->data - skb->head; +} + +static inline void skb_set_transport_header(struct sk_buff *skb, + const int offset) +{ + skb_reset_transport_header(skb); + skb->transport_header += offset; +} + +static inline unsigned char *skb_network_header(const struct sk_buff *skb) +{ + return skb->head + skb->network_header; +} + +static inline void skb_reset_network_header(struct sk_buff *skb) +{ + skb->network_header = skb->data - skb->head; +} + +static inline void skb_set_network_header(struct sk_buff *skb, const int offset) +{ + skb_reset_network_header(skb); + skb->network_header += offset; +} + +static inline unsigned char *skb_mac_header(const struct sk_buff *skb) +{ + return skb->head + skb->mac_header; +} + +static inline int skb_mac_header_was_set(const struct sk_buff *skb) +{ + return skb->mac_header != (typeof(skb->mac_header))~0U; +} + +static inline void skb_reset_mac_header(struct sk_buff *skb) +{ + skb->mac_header = skb->data - skb->head; +} + +static inline void skb_set_mac_header(struct sk_buff *skb, const int offset) +{ + skb_reset_mac_header(skb); + skb->mac_header += offset; +} + +static inline void skb_pop_mac_header(struct sk_buff *skb) +{ + skb->mac_header = skb->network_header; +} + +static inline void skb_probe_transport_header(struct sk_buff *skb, + const int offset_hint) +{ + struct flow_keys keys; + + if (skb_transport_header_was_set(skb)) + return; + else if (skb_flow_dissect(skb, &keys)) + skb_set_transport_header(skb, keys.thoff); + else + skb_set_transport_header(skb, offset_hint); +} + +static inline void skb_mac_header_rebuild(struct sk_buff *skb) +{ + if (skb_mac_header_was_set(skb)) { + const unsigned char *old_mac = skb_mac_header(skb); + + skb_set_mac_header(skb, -skb->mac_len); + memmove(skb_mac_header(skb), old_mac, skb->mac_len); + } +} + +static inline int skb_checksum_start_offset(const struct sk_buff *skb) +{ + return skb->csum_start - skb_headroom(skb); +} + +static inline int skb_transport_offset(const struct sk_buff *skb) +{ + return skb_transport_header(skb) - skb->data; +} + +static inline u32 skb_network_header_len(const struct sk_buff *skb) +{ + return skb->transport_header - skb->network_header; +} + +static inline u32 skb_inner_network_header_len(const struct sk_buff *skb) +{ + return skb->inner_transport_header - skb->inner_network_header; +} + +static inline int skb_network_offset(const struct sk_buff *skb) +{ + return skb_network_header(skb) - skb->data; +} + +static inline int skb_inner_network_offset(const struct sk_buff *skb) +{ + return skb_inner_network_header(skb) - skb->data; +} + +static inline int pskb_network_may_pull(struct sk_buff *skb, unsigned int len) +{ + return pskb_may_pull(skb, skb_network_offset(skb) + len); +} + +/* + * CPUs often take a performance hit when accessing unaligned memory + * locations. The actual performance hit varies, it can be small if the + * hardware handles it or large if we have to take an exception and fix it + * in software. + * + * Since an ethernet header is 14 bytes network drivers often end up with + * the IP header at an unaligned offset. The IP header can be aligned by + * shifting the start of the packet by 2 bytes. Drivers should do this + * with: + * + * skb_reserve(skb, NET_IP_ALIGN); + * + * The downside to this alignment of the IP header is that the DMA is now + * unaligned. On some architectures the cost of an unaligned DMA is high + * and this cost outweighs the gains made by aligning the IP header. + * + * Since this trade off varies between architectures, we allow NET_IP_ALIGN + * to be overridden. + */ +#ifndef NET_IP_ALIGN +#define NET_IP_ALIGN 2 +#endif + +/* + * The networking layer reserves some headroom in skb data (via + * dev_alloc_skb). This is used to avoid having to reallocate skb data when + * the header has to grow. In the default case, if the header has to grow + * 32 bytes or less we avoid the reallocation. + * + * Unfortunately this headroom changes the DMA alignment of the resulting + * network packet. As for NET_IP_ALIGN, this unaligned DMA is expensive + * on some architectures. An architecture can override this value, + * perhaps setting it to a cacheline in size (since that will maintain + * cacheline alignment of the DMA). It must be a power of 2. + * + * Various parts of the networking layer expect at least 32 bytes of + * headroom, you should not reduce this. + * + * Using max(32, L1_CACHE_BYTES) makes sense (especially with RPS) + * to reduce average number of cache lines per packet. + * get_rps_cpus() for example only access one 64 bytes aligned block : + * NET_IP_ALIGN(2) + ethernet_header(14) + IP_header(20/40) + ports(8) + */ +#ifndef NET_SKB_PAD +#define NET_SKB_PAD max(32, L1_CACHE_BYTES) +#endif + +int ___pskb_trim(struct sk_buff *skb, unsigned int len); + +static inline void __skb_trim(struct sk_buff *skb, unsigned int len) +{ + if (unlikely(skb_is_nonlinear(skb))) { + WARN_ON(1); + return; + } + skb->len = len; + skb_set_tail_pointer(skb, len); +} + +void skb_trim(struct sk_buff *skb, unsigned int len); + +static inline int __pskb_trim(struct sk_buff *skb, unsigned int len) +{ + if (skb->data_len) + return ___pskb_trim(skb, len); + __skb_trim(skb, len); + return 0; +} + +static inline int pskb_trim(struct sk_buff *skb, unsigned int len) +{ + return (len < skb->len) ? __pskb_trim(skb, len) : 0; +} + +/** + * pskb_trim_unique - remove end from a paged unique (not cloned) buffer + * @skb: buffer to alter + * @len: new length + * + * This is identical to pskb_trim except that the caller knows that + * the skb is not cloned so we should never get an error due to out- + * of-memory. + */ +static inline void pskb_trim_unique(struct sk_buff *skb, unsigned int len) +{ + int err = pskb_trim(skb, len); + BUG_ON(err); +} + +/** + * skb_orphan - orphan a buffer + * @skb: buffer to orphan + * + * If a buffer currently has an owner then we call the owner's + * destructor function and make the @skb unowned. The buffer continues + * to exist but is no longer charged to its former owner. + */ +static inline void skb_orphan(struct sk_buff *skb) +{ + if (skb->destructor) { + skb->destructor(skb); + skb->destructor = NULL; + skb->sk = NULL; + } else { + BUG_ON(skb->sk); + } +} + +/** + * skb_orphan_frags - orphan the frags contained in a buffer + * @skb: buffer to orphan frags from + * @gfp_mask: allocation mask for replacement pages + * + * For each frag in the SKB which needs a destructor (i.e. has an + * owner) create a copy of that frag and release the original + * page by calling the destructor. + */ +static inline int skb_orphan_frags(struct sk_buff *skb, gfp_t gfp_mask) +{ + if (likely(!(skb_shinfo(skb)->tx_flags & SKBTX_DEV_ZEROCOPY))) + return 0; + return skb_copy_ubufs(skb, gfp_mask); +} + +/** + * __skb_queue_purge - empty a list + * @list: list to empty + * + * Delete all buffers on an &sk_buff list. Each buffer is removed from + * the list and one reference dropped. This function does not take the + * list lock and the caller must hold the relevant locks to use it. + */ +void skb_queue_purge(struct sk_buff_head *list); +static inline void __skb_queue_purge(struct sk_buff_head *list) +{ + struct sk_buff *skb; + while ((skb = __skb_dequeue(list)) != NULL) + kfree_skb(skb); +} + +#define NETDEV_FRAG_PAGE_MAX_ORDER get_order(32768) +#define NETDEV_FRAG_PAGE_MAX_SIZE (PAGE_SIZE << NETDEV_FRAG_PAGE_MAX_ORDER) +#define NETDEV_PAGECNT_MAX_BIAS NETDEV_FRAG_PAGE_MAX_SIZE + +void *netdev_alloc_frag(unsigned int fragsz); + +struct sk_buff *__netdev_alloc_skb(struct net_device *dev, unsigned int length, + gfp_t gfp_mask); + +/** + * netdev_alloc_skb - allocate an skbuff for rx on a specific device + * @dev: network device to receive on + * @length: length to allocate + * + * Allocate a new &sk_buff and assign it a usage count of one. The + * buffer has unspecified headroom built in. Users should allocate + * the headroom they think they need without accounting for the + * built in space. The built in space is used for optimisations. + * + * %NULL is returned if there is no free memory. Although this function + * allocates memory it can be called from an interrupt. + */ +static inline struct sk_buff *netdev_alloc_skb(struct net_device *dev, + unsigned int length) +{ + return __netdev_alloc_skb(dev, length, GFP_ATOMIC); +} + +/* legacy helper around __netdev_alloc_skb() */ +static inline struct sk_buff *__dev_alloc_skb(unsigned int length, + gfp_t gfp_mask) +{ + return __netdev_alloc_skb(NULL, length, gfp_mask); +} + +/* legacy helper around netdev_alloc_skb() */ +static inline struct sk_buff *dev_alloc_skb(unsigned int length) +{ + return netdev_alloc_skb(NULL, length); +} + + +static inline struct sk_buff *__netdev_alloc_skb_ip_align(struct net_device *dev, + unsigned int length, gfp_t gfp) +{ + struct sk_buff *skb = __netdev_alloc_skb(dev, length + NET_IP_ALIGN, gfp); + + if (NET_IP_ALIGN && skb) + skb_reserve(skb, NET_IP_ALIGN); + return skb; +} + +static inline struct sk_buff *netdev_alloc_skb_ip_align(struct net_device *dev, + unsigned int length) +{ + return __netdev_alloc_skb_ip_align(dev, length, GFP_ATOMIC); +} + +/** + * __skb_alloc_pages - allocate pages for ps-rx on a skb and preserve pfmemalloc data + * @gfp_mask: alloc_pages_node mask. Set __GFP_NOMEMALLOC if not for network packet RX + * @skb: skb to set pfmemalloc on if __GFP_MEMALLOC is used + * @order: size of the allocation + * + * Allocate a new page. + * + * %NULL is returned if there is no free memory. +*/ +static inline struct page *__skb_alloc_pages(gfp_t gfp_mask, + struct sk_buff *skb, + unsigned int order) +{ + struct page *page; + + gfp_mask |= __GFP_COLD; + + if (!(gfp_mask & __GFP_NOMEMALLOC)) + gfp_mask |= __GFP_MEMALLOC; + + page = alloc_pages_node(NUMA_NO_NODE, gfp_mask, order); + if (skb && page && page->pfmemalloc) + skb->pfmemalloc = true; + + return page; +} + +/** + * __skb_alloc_page - allocate a page for ps-rx for a given skb and preserve pfmemalloc data + * @gfp_mask: alloc_pages_node mask. Set __GFP_NOMEMALLOC if not for network packet RX + * @skb: skb to set pfmemalloc on if __GFP_MEMALLOC is used + * + * Allocate a new page. + * + * %NULL is returned if there is no free memory. + */ +static inline struct page *__skb_alloc_page(gfp_t gfp_mask, + struct sk_buff *skb) +{ + return __skb_alloc_pages(gfp_mask, skb, 0); +} + +/** + * skb_propagate_pfmemalloc - Propagate pfmemalloc if skb is allocated after RX page + * @page: The page that was allocated from skb_alloc_page + * @skb: The skb that may need pfmemalloc set + */ +static inline void skb_propagate_pfmemalloc(struct page *page, + struct sk_buff *skb) +{ + if (page && page->pfmemalloc) + skb->pfmemalloc = true; +} + +/** + * skb_frag_page - retrieve the page referred to by a paged fragment + * @frag: the paged fragment + * + * Returns the &struct page associated with @frag. + */ +static inline struct page *skb_frag_page(const skb_frag_t *frag) +{ + return frag->page.p; +} + +/** + * __skb_frag_ref - take an addition reference on a paged fragment. + * @frag: the paged fragment + * + * Takes an additional reference on the paged fragment @frag. + */ +static inline void __skb_frag_ref(skb_frag_t *frag) +{ + get_page(skb_frag_page(frag)); +} + +/** + * skb_frag_ref - take an addition reference on a paged fragment of an skb. + * @skb: the buffer + * @f: the fragment offset. + * + * Takes an additional reference on the @f'th paged fragment of @skb. + */ +static inline void skb_frag_ref(struct sk_buff *skb, int f) +{ + __skb_frag_ref(&skb_shinfo(skb)->frags[f]); +} + +/** + * __skb_frag_unref - release a reference on a paged fragment. + * @frag: the paged fragment + * + * Releases a reference on the paged fragment @frag. + */ +static inline void __skb_frag_unref(skb_frag_t *frag) +{ + put_page(skb_frag_page(frag)); +} + +/** + * skb_frag_unref - release a reference on a paged fragment of an skb. + * @skb: the buffer + * @f: the fragment offset + * + * Releases a reference on the @f'th paged fragment of @skb. + */ +static inline void skb_frag_unref(struct sk_buff *skb, int f) +{ + __skb_frag_unref(&skb_shinfo(skb)->frags[f]); +} + +/** + * skb_frag_address - gets the address of the data contained in a paged fragment + * @frag: the paged fragment buffer + * + * Returns the address of the data within @frag. The page must already + * be mapped. + */ +static inline void *skb_frag_address(const skb_frag_t *frag) +{ + return page_address(skb_frag_page(frag)) + frag->page_offset; +} + +/** + * skb_frag_address_safe - gets the address of the data contained in a paged fragment + * @frag: the paged fragment buffer + * + * Returns the address of the data within @frag. Checks that the page + * is mapped and returns %NULL otherwise. + */ +static inline void *skb_frag_address_safe(const skb_frag_t *frag) +{ + void *ptr = page_address(skb_frag_page(frag)); + if (unlikely(!ptr)) + return NULL; + + return ptr + frag->page_offset; +} + +/** + * __skb_frag_set_page - sets the page contained in a paged fragment + * @frag: the paged fragment + * @page: the page to set + * + * Sets the fragment @frag to contain @page. + */ +static inline void __skb_frag_set_page(skb_frag_t *frag, struct page *page) +{ + frag->page.p = page; +} + +/** + * skb_frag_set_page - sets the page contained in a paged fragment of an skb + * @skb: the buffer + * @f: the fragment offset + * @page: the page to set + * + * Sets the @f'th fragment of @skb to contain @page. + */ +static inline void skb_frag_set_page(struct sk_buff *skb, int f, + struct page *page) +{ + __skb_frag_set_page(&skb_shinfo(skb)->frags[f], page); +} + +bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t prio); + +/** + * skb_frag_dma_map - maps a paged fragment via the DMA API + * @dev: the device to map the fragment to + * @frag: the paged fragment to map + * @offset: the offset within the fragment (starting at the + * fragment's own offset) + * @size: the number of bytes to map + * @dir: the direction of the mapping (%PCI_DMA_*) + * + * Maps the page associated with @frag to @device. + */ +static inline dma_addr_t skb_frag_dma_map(struct device *dev, + const skb_frag_t *frag, + size_t offset, size_t size, + enum dma_data_direction dir) +{ + return dma_map_page(dev, skb_frag_page(frag), + frag->page_offset + offset, size, dir); +} + +static inline struct sk_buff *pskb_copy(struct sk_buff *skb, + gfp_t gfp_mask) +{ + return __pskb_copy(skb, skb_headroom(skb), gfp_mask); +} + + +static inline struct sk_buff *pskb_copy_for_clone(struct sk_buff *skb, + gfp_t gfp_mask) +{ + return __pskb_copy_fclone(skb, skb_headroom(skb), gfp_mask, true); +} + + +/** + * skb_clone_writable - is the header of a clone writable + * @skb: buffer to check + * @len: length up to which to write + * + * Returns true if modifying the header part of the cloned buffer + * does not requires the data to be copied. + */ +static inline int skb_clone_writable(const struct sk_buff *skb, unsigned int len) +{ + return !skb_header_cloned(skb) && + skb_headroom(skb) + len <= skb->hdr_len; +} + +static inline int __skb_cow(struct sk_buff *skb, unsigned int headroom, + int cloned) +{ + int delta = 0; + + if (headroom > skb_headroom(skb)) + delta = headroom - skb_headroom(skb); + + if (delta || cloned) + return pskb_expand_head(skb, ALIGN(delta, NET_SKB_PAD), 0, + GFP_ATOMIC); + return 0; +} + +/** + * skb_cow - copy header of skb when it is required + * @skb: buffer to cow + * @headroom: needed headroom + * + * If the skb passed lacks sufficient headroom or its data part + * is shared, data is reallocated. If reallocation fails, an error + * is returned and original skb is not changed. + * + * The result is skb with writable area skb->head...skb->tail + * and at least @headroom of space at head. + */ +static inline int skb_cow(struct sk_buff *skb, unsigned int headroom) +{ + return __skb_cow(skb, headroom, skb_cloned(skb)); +} + +/** + * skb_cow_head - skb_cow but only making the head writable + * @skb: buffer to cow + * @headroom: needed headroom + * + * This function is identical to skb_cow except that we replace the + * skb_cloned check by skb_header_cloned. It should be used when + * you only need to push on some header and do not need to modify + * the data. + */ +static inline int skb_cow_head(struct sk_buff *skb, unsigned int headroom) +{ + return __skb_cow(skb, headroom, skb_header_cloned(skb)); +} + +/** + * skb_padto - pad an skbuff up to a minimal size + * @skb: buffer to pad + * @len: minimal length + * + * Pads up a buffer to ensure the trailing bytes exist and are + * blanked. If the buffer already contains sufficient data it + * is untouched. Otherwise it is extended. Returns zero on + * success. The skb is freed on error. + */ + +static inline int skb_padto(struct sk_buff *skb, unsigned int len) +{ + unsigned int size = skb->len; + if (likely(size >= len)) + return 0; + return skb_pad(skb, len - size); +} + +static inline int skb_add_data(struct sk_buff *skb, + char __user *from, int copy) +{ + const int off = skb->len; + + if (skb->ip_summed == CHECKSUM_NONE) { + int err = 0; + __wsum csum = csum_and_copy_from_user(from, skb_put(skb, copy), + copy, 0, &err); + if (!err) { + skb->csum = csum_block_add(skb->csum, csum, off); + return 0; + } + } else if (!copy_from_user(skb_put(skb, copy), from, copy)) + return 0; + + __skb_trim(skb, off); + return -EFAULT; +} + +static inline bool skb_can_coalesce(struct sk_buff *skb, int i, + const struct page *page, int off) +{ + if (i) { + const struct skb_frag_struct *frag = &skb_shinfo(skb)->frags[i - 1]; + + return page == skb_frag_page(frag) && + off == frag->page_offset + skb_frag_size(frag); + } + return false; +} + +static inline int __skb_linearize(struct sk_buff *skb) +{ + return __pskb_pull_tail(skb, skb->data_len) ? 0 : -ENOMEM; +} + +/** + * skb_linearize - convert paged skb to linear one + * @skb: buffer to linarize + * + * If there is no free memory -ENOMEM is returned, otherwise zero + * is returned and the old skb data released. + */ +static inline int skb_linearize(struct sk_buff *skb) +{ + return skb_is_nonlinear(skb) ? __skb_linearize(skb) : 0; +} + +/** + * skb_has_shared_frag - can any frag be overwritten + * @skb: buffer to test + * + * Return true if the skb has at least one frag that might be modified + * by an external entity (as in vmsplice()/sendfile()) + */ +static inline bool skb_has_shared_frag(const struct sk_buff *skb) +{ + return skb_is_nonlinear(skb) && + skb_shinfo(skb)->tx_flags & SKBTX_SHARED_FRAG; +} + +/** + * skb_linearize_cow - make sure skb is linear and writable + * @skb: buffer to process + * + * If there is no free memory -ENOMEM is returned, otherwise zero + * is returned and the old skb data released. + */ +static inline int skb_linearize_cow(struct sk_buff *skb) +{ + return skb_is_nonlinear(skb) || skb_cloned(skb) ? + __skb_linearize(skb) : 0; +} + +/** + * skb_postpull_rcsum - update checksum for received skb after pull + * @skb: buffer to update + * @start: start of data before pull + * @len: length of data pulled + * + * After doing a pull on a received packet, you need to call this to + * update the CHECKSUM_COMPLETE checksum, or set ip_summed to + * CHECKSUM_NONE so that it can be recomputed from scratch. + */ + +static inline void skb_postpull_rcsum(struct sk_buff *skb, + const void *start, unsigned int len) +{ + if (skb->ip_summed == CHECKSUM_COMPLETE) + skb->csum = csum_sub(skb->csum, csum_partial(start, len, 0)); +} + +unsigned char *skb_pull_rcsum(struct sk_buff *skb, unsigned int len); + +/** + * pskb_trim_rcsum - trim received skb and update checksum + * @skb: buffer to trim + * @len: new length + * + * This is exactly the same as pskb_trim except that it ensures the + * checksum of received packets are still valid after the operation. + */ + +static inline int pskb_trim_rcsum(struct sk_buff *skb, unsigned int len) +{ + if (likely(len >= skb->len)) + return 0; + if (skb->ip_summed == CHECKSUM_COMPLETE) + skb->ip_summed = CHECKSUM_NONE; + return __pskb_trim(skb, len); +} + +#define skb_queue_walk(queue, skb) \ + for (skb = (queue)->next; \ + skb != (struct sk_buff *)(queue); \ + skb = skb->next) + +#define skb_queue_walk_safe(queue, skb, tmp) \ + for (skb = (queue)->next, tmp = skb->next; \ + skb != (struct sk_buff *)(queue); \ + skb = tmp, tmp = skb->next) + +#define skb_queue_walk_from(queue, skb) \ + for (; skb != (struct sk_buff *)(queue); \ + skb = skb->next) + +#define skb_queue_walk_from_safe(queue, skb, tmp) \ + for (tmp = skb->next; \ + skb != (struct sk_buff *)(queue); \ + skb = tmp, tmp = skb->next) + +#define skb_queue_reverse_walk(queue, skb) \ + for (skb = (queue)->prev; \ + skb != (struct sk_buff *)(queue); \ + skb = skb->prev) + +#define skb_queue_reverse_walk_safe(queue, skb, tmp) \ + for (skb = (queue)->prev, tmp = skb->prev; \ + skb != (struct sk_buff *)(queue); \ + skb = tmp, tmp = skb->prev) + +#define skb_queue_reverse_walk_from_safe(queue, skb, tmp) \ + for (tmp = skb->prev; \ + skb != (struct sk_buff *)(queue); \ + skb = tmp, tmp = skb->prev) + +static inline bool skb_has_frag_list(const struct sk_buff *skb) +{ + return skb_shinfo(skb)->frag_list != NULL; +} + +static inline void skb_frag_list_init(struct sk_buff *skb) +{ + skb_shinfo(skb)->frag_list = NULL; +} + +static inline void skb_frag_add_head(struct sk_buff *skb, struct sk_buff *frag) +{ + frag->next = skb_shinfo(skb)->frag_list; + skb_shinfo(skb)->frag_list = frag; +} + +#define skb_walk_frags(skb, iter) \ + for (iter = skb_shinfo(skb)->frag_list; iter; iter = iter->next) + +struct sk_buff *__skb_recv_datagram(struct sock *sk, unsigned flags, + int *peeked, int *off, int *err); +struct sk_buff *skb_recv_datagram(struct sock *sk, unsigned flags, int noblock, + int *err); +unsigned int datagram_poll(struct file *file, struct socket *sock, + struct poll_table_struct *wait); +int skb_copy_datagram_iovec(const struct sk_buff *from, int offset, + struct iovec *to, int size); +int skb_copy_and_csum_datagram_iovec(struct sk_buff *skb, int hlen, + struct iovec *iov); +int skb_copy_datagram_from_iovec(struct sk_buff *skb, int offset, + const struct iovec *from, int from_offset, + int len); +int zerocopy_sg_from_iovec(struct sk_buff *skb, const struct iovec *frm, + int offset, size_t count); +int skb_copy_datagram_const_iovec(const struct sk_buff *from, int offset, + const struct iovec *to, int to_offset, + int size); +void skb_free_datagram(struct sock *sk, struct sk_buff *skb); +void skb_free_datagram_locked(struct sock *sk, struct sk_buff *skb); +int skb_kill_datagram(struct sock *sk, struct sk_buff *skb, unsigned int flags); +int skb_copy_bits(const struct sk_buff *skb, int offset, void *to, int len); +int skb_store_bits(struct sk_buff *skb, int offset, const void *from, int len); +__wsum skb_copy_and_csum_bits(const struct sk_buff *skb, int offset, u8 *to, + int len, __wsum csum); +int skb_splice_bits(struct sk_buff *skb, unsigned int offset, + struct pipe_inode_info *pipe, unsigned int len, + unsigned int flags); +void skb_copy_and_csum_dev(const struct sk_buff *skb, u8 *to); +unsigned int skb_zerocopy_headlen(const struct sk_buff *from); +int skb_zerocopy(struct sk_buff *to, struct sk_buff *from, + int len, int hlen); +void skb_split(struct sk_buff *skb, struct sk_buff *skb1, const u32 len); +int skb_shift(struct sk_buff *tgt, struct sk_buff *skb, int shiftlen); +void skb_scrub_packet(struct sk_buff *skb, bool xnet); +unsigned int skb_gso_transport_seglen(const struct sk_buff *skb); +struct sk_buff *skb_segment(struct sk_buff *skb, netdev_features_t features); +struct sk_buff *skb_vlan_untag(struct sk_buff *skb); + +struct skb_checksum_ops { + __wsum (*update)(const void *mem, int len, __wsum wsum); + __wsum (*combine)(__wsum csum, __wsum csum2, int offset, int len); +}; + +__wsum __skb_checksum(const struct sk_buff *skb, int offset, int len, + __wsum csum, const struct skb_checksum_ops *ops); +__wsum skb_checksum(const struct sk_buff *skb, int offset, int len, + __wsum csum); + +static inline void *__skb_header_pointer(const struct sk_buff *skb, int offset, + int len, void *data, int hlen, void *buffer) +{ + if (hlen - offset >= len) + return data + offset; + + if (!skb || + skb_copy_bits(skb, offset, buffer, len) < 0) + return NULL; + + return buffer; +} + +static inline void *skb_header_pointer(const struct sk_buff *skb, int offset, + int len, void *buffer) +{ + return __skb_header_pointer(skb, offset, len, skb->data, + skb_headlen(skb), buffer); +} + +/** + * skb_needs_linearize - check if we need to linearize a given skb + * depending on the given device features. + * @skb: socket buffer to check + * @features: net device features + * + * Returns true if either: + * 1. skb has frag_list and the device doesn't support FRAGLIST, or + * 2. skb is fragmented and the device does not support SG. + */ +static inline bool skb_needs_linearize(struct sk_buff *skb, + netdev_features_t features) +{ + return skb_is_nonlinear(skb) && + ((skb_has_frag_list(skb) && !(features & NETIF_F_FRAGLIST)) || + (skb_shinfo(skb)->nr_frags && !(features & NETIF_F_SG))); +} + +static inline void skb_copy_from_linear_data(const struct sk_buff *skb, + void *to, + const unsigned int len) +{ + memcpy(to, skb->data, len); +} + +static inline void skb_copy_from_linear_data_offset(const struct sk_buff *skb, + const int offset, void *to, + const unsigned int len) +{ + memcpy(to, skb->data + offset, len); +} + +static inline void skb_copy_to_linear_data(struct sk_buff *skb, + const void *from, + const unsigned int len) +{ + memcpy(skb->data, from, len); +} + +static inline void skb_copy_to_linear_data_offset(struct sk_buff *skb, + const int offset, + const void *from, + const unsigned int len) +{ + memcpy(skb->data + offset, from, len); +} + +void skb_init(void); + +static inline ktime_t skb_get_ktime(const struct sk_buff *skb) +{ + return skb->tstamp; +} + +/** + * skb_get_timestamp - get timestamp from a skb + * @skb: skb to get stamp from + * @stamp: pointer to struct timeval to store stamp in + * + * Timestamps are stored in the skb as offsets to a base timestamp. + * This function converts the offset back to a struct timeval and stores + * it in stamp. + */ +static inline void skb_get_timestamp(const struct sk_buff *skb, + struct timeval *stamp) +{ + *stamp = ktime_to_timeval(skb->tstamp); +} + +static inline void skb_get_timestampns(const struct sk_buff *skb, + struct timespec *stamp) +{ + *stamp = ktime_to_timespec(skb->tstamp); +} + +static inline void __net_timestamp(struct sk_buff *skb) +{ + skb->tstamp = ktime_get_real(); +} + +static inline ktime_t net_timedelta(ktime_t t) +{ + return ktime_sub(ktime_get_real(), t); +} + +static inline ktime_t net_invalid_timestamp(void) +{ + return ktime_set(0, 0); +} + +struct sk_buff *skb_clone_sk(struct sk_buff *skb); + +#ifdef CONFIG_NETWORK_PHY_TIMESTAMPING + +void skb_clone_tx_timestamp(struct sk_buff *skb); +bool skb_defer_rx_timestamp(struct sk_buff *skb); + +#else /* CONFIG_NETWORK_PHY_TIMESTAMPING */ + +static inline void skb_clone_tx_timestamp(struct sk_buff *skb) +{ +} + +static inline bool skb_defer_rx_timestamp(struct sk_buff *skb) +{ + return false; +} + +#endif /* !CONFIG_NETWORK_PHY_TIMESTAMPING */ + +/** + * skb_complete_tx_timestamp() - deliver cloned skb with tx timestamps + * + * PHY drivers may accept clones of transmitted packets for + * timestamping via their phy_driver.txtstamp method. These drivers + * must call this function to return the skb back to the stack, with + * or without a timestamp. + * + * @skb: clone of the the original outgoing packet + * @hwtstamps: hardware time stamps, may be NULL if not available + * + */ +void skb_complete_tx_timestamp(struct sk_buff *skb, + struct skb_shared_hwtstamps *hwtstamps); + +void __skb_tstamp_tx(struct sk_buff *orig_skb, + struct skb_shared_hwtstamps *hwtstamps, + struct sock *sk, int tstype); + +/** + * skb_tstamp_tx - queue clone of skb with send time stamps + * @orig_skb: the original outgoing packet + * @hwtstamps: hardware time stamps, may be NULL if not available + * + * If the skb has a socket associated, then this function clones the + * skb (thus sharing the actual data and optional structures), stores + * the optional hardware time stamping information (if non NULL) or + * generates a software time stamp (otherwise), then queues the clone + * to the error queue of the socket. Errors are silently ignored. + */ +void skb_tstamp_tx(struct sk_buff *orig_skb, + struct skb_shared_hwtstamps *hwtstamps); + +static inline void sw_tx_timestamp(struct sk_buff *skb) +{ + if (skb_shinfo(skb)->tx_flags & SKBTX_SW_TSTAMP && + !(skb_shinfo(skb)->tx_flags & SKBTX_IN_PROGRESS)) + skb_tstamp_tx(skb, NULL); +} + +/** + * skb_tx_timestamp() - Driver hook for transmit timestamping + * + * Ethernet MAC Drivers should call this function in their hard_xmit() + * function immediately before giving the sk_buff to the MAC hardware. + * + * Specifically, one should make absolutely sure that this function is + * called before TX completion of this packet can trigger. Otherwise + * the packet could potentially already be freed. + * + * @skb: A socket buffer. + */ +static inline void skb_tx_timestamp(struct sk_buff *skb) +{ + skb_clone_tx_timestamp(skb); + sw_tx_timestamp(skb); +} + +/** + * skb_complete_wifi_ack - deliver skb with wifi status + * + * @skb: the original outgoing packet + * @acked: ack status + * + */ +void skb_complete_wifi_ack(struct sk_buff *skb, bool acked); + +__sum16 __skb_checksum_complete_head(struct sk_buff *skb, int len); +__sum16 __skb_checksum_complete(struct sk_buff *skb); + +static inline int skb_csum_unnecessary(const struct sk_buff *skb) +{ + return ((skb->ip_summed & CHECKSUM_UNNECESSARY) || skb->csum_valid); +} + +/** + * skb_checksum_complete - Calculate checksum of an entire packet + * @skb: packet to process + * + * This function calculates the checksum over the entire packet plus + * the value of skb->csum. The latter can be used to supply the + * checksum of a pseudo header as used by TCP/UDP. It returns the + * checksum. + * + * For protocols that contain complete checksums such as ICMP/TCP/UDP, + * this function can be used to verify that checksum on received + * packets. In that case the function should return zero if the + * checksum is correct. In particular, this function will return zero + * if skb->ip_summed is CHECKSUM_UNNECESSARY which indicates that the + * hardware has already verified the correctness of the checksum. + */ +static inline __sum16 skb_checksum_complete(struct sk_buff *skb) +{ + return skb_csum_unnecessary(skb) ? + 0 : __skb_checksum_complete(skb); +} + +static inline void __skb_decr_checksum_unnecessary(struct sk_buff *skb) +{ + if (skb->ip_summed == CHECKSUM_UNNECESSARY) { + if (skb->csum_level == 0) + skb->ip_summed = CHECKSUM_NONE; + else + skb->csum_level--; + } +} + +static inline void __skb_incr_checksum_unnecessary(struct sk_buff *skb) +{ + if (skb->ip_summed == CHECKSUM_UNNECESSARY) { + if (skb->csum_level < SKB_MAX_CSUM_LEVEL) + skb->csum_level++; + } else if (skb->ip_summed == CHECKSUM_NONE) { + skb->ip_summed = CHECKSUM_UNNECESSARY; + skb->csum_level = 0; + } +} + +static inline void __skb_mark_checksum_bad(struct sk_buff *skb) +{ + /* Mark current checksum as bad (typically called from GRO + * path). In the case that ip_summed is CHECKSUM_NONE + * this must be the first checksum encountered in the packet. + * When ip_summed is CHECKSUM_UNNECESSARY, this is the first + * checksum after the last one validated. For UDP, a zero + * checksum can not be marked as bad. + */ + + if (skb->ip_summed == CHECKSUM_NONE || + skb->ip_summed == CHECKSUM_UNNECESSARY) + skb->csum_bad = 1; +} + +/* Check if we need to perform checksum complete validation. + * + * Returns true if checksum complete is needed, false otherwise + * (either checksum is unnecessary or zero checksum is allowed). + */ +static inline bool __skb_checksum_validate_needed(struct sk_buff *skb, + bool zero_okay, + __sum16 check) +{ + if (skb_csum_unnecessary(skb) || (zero_okay && !check)) { + skb->csum_valid = 1; + __skb_decr_checksum_unnecessary(skb); + return false; + } + + return true; +} + +/* For small packets <= CHECKSUM_BREAK peform checksum complete directly + * in checksum_init. + */ +#define CHECKSUM_BREAK 76 + +/* Unset checksum-complete + * + * Unset checksum complete can be done when packet is being modified + * (uncompressed for instance) and checksum-complete value is + * invalidated. + */ +static inline void skb_checksum_complete_unset(struct sk_buff *skb) +{ + if (skb->ip_summed == CHECKSUM_COMPLETE) + skb->ip_summed = CHECKSUM_NONE; +} + +/* Validate (init) checksum based on checksum complete. + * + * Return values: + * 0: checksum is validated or try to in skb_checksum_complete. In the latter + * case the ip_summed will not be CHECKSUM_UNNECESSARY and the pseudo + * checksum is stored in skb->csum for use in __skb_checksum_complete + * non-zero: value of invalid checksum + * + */ +static inline __sum16 __skb_checksum_validate_complete(struct sk_buff *skb, + bool complete, + __wsum psum) +{ + if (skb->ip_summed == CHECKSUM_COMPLETE) { + if (!csum_fold(csum_add(psum, skb->csum))) { + skb->csum_valid = 1; + return 0; + } + } else if (skb->csum_bad) { + /* ip_summed == CHECKSUM_NONE in this case */ + return 1; + } + + skb->csum = psum; + + if (complete || skb->len <= CHECKSUM_BREAK) { + __sum16 csum; + + csum = __skb_checksum_complete(skb); + skb->csum_valid = !csum; + return csum; + } + + return 0; +} + +static inline __wsum null_compute_pseudo(struct sk_buff *skb, int proto) +{ + return 0; +} + +/* Perform checksum validate (init). Note that this is a macro since we only + * want to calculate the pseudo header which is an input function if necessary. + * First we try to validate without any computation (checksum unnecessary) and + * then calculate based on checksum complete calling the function to compute + * pseudo header. + * + * Return values: + * 0: checksum is validated or try to in skb_checksum_complete + * non-zero: value of invalid checksum + */ +#define __skb_checksum_validate(skb, proto, complete, \ + zero_okay, check, compute_pseudo) \ +({ \ + __sum16 __ret = 0; \ + skb->csum_valid = 0; \ + if (__skb_checksum_validate_needed(skb, zero_okay, check)) \ + __ret = __skb_checksum_validate_complete(skb, \ + complete, compute_pseudo(skb, proto)); \ + __ret; \ +}) + +#define skb_checksum_init(skb, proto, compute_pseudo) \ + __skb_checksum_validate(skb, proto, false, false, 0, compute_pseudo) + +#define skb_checksum_init_zero_check(skb, proto, check, compute_pseudo) \ + __skb_checksum_validate(skb, proto, false, true, check, compute_pseudo) + +#define skb_checksum_validate(skb, proto, compute_pseudo) \ + __skb_checksum_validate(skb, proto, true, false, 0, compute_pseudo) + +#define skb_checksum_validate_zero_check(skb, proto, check, \ + compute_pseudo) \ + __skb_checksum_validate_(skb, proto, true, true, check, compute_pseudo) + +#define skb_checksum_simple_validate(skb) \ + __skb_checksum_validate(skb, 0, true, false, 0, null_compute_pseudo) + +static inline bool __skb_checksum_convert_check(struct sk_buff *skb) +{ + return (skb->ip_summed == CHECKSUM_NONE && + skb->csum_valid && !skb->csum_bad); +} + +static inline void __skb_checksum_convert(struct sk_buff *skb, + __sum16 check, __wsum pseudo) +{ + skb->csum = ~pseudo; + skb->ip_summed = CHECKSUM_COMPLETE; +} + +#define skb_checksum_try_convert(skb, proto, check, compute_pseudo) \ +do { \ + if (__skb_checksum_convert_check(skb)) \ + __skb_checksum_convert(skb, check, \ + compute_pseudo(skb, proto)); \ +} while (0) + +#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) +void nf_conntrack_destroy(struct nf_conntrack *nfct); +static inline void nf_conntrack_put(struct nf_conntrack *nfct) +{ + if (nfct && atomic_dec_and_test(&nfct->use)) + nf_conntrack_destroy(nfct); +} +static inline void nf_conntrack_get(struct nf_conntrack *nfct) +{ + if (nfct) + atomic_inc(&nfct->use); +} +#endif +#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER) +static inline void nf_bridge_put(struct nf_bridge_info *nf_bridge) +{ + if (nf_bridge && atomic_dec_and_test(&nf_bridge->use)) + kfree(nf_bridge); +} +static inline void nf_bridge_get(struct nf_bridge_info *nf_bridge) +{ + if (nf_bridge) + atomic_inc(&nf_bridge->use); +} +#endif /* CONFIG_BRIDGE_NETFILTER */ +static inline void nf_reset(struct sk_buff *skb) +{ +#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) + nf_conntrack_put(skb->nfct); + skb->nfct = NULL; +#endif +#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER) + nf_bridge_put(skb->nf_bridge); + skb->nf_bridge = NULL; +#endif +} + +static inline void nf_reset_trace(struct sk_buff *skb) +{ +#if IS_ENABLED(CONFIG_NETFILTER_XT_TARGET_TRACE) || defined(CONFIG_NF_TABLES) + skb->nf_trace = 0; +#endif +} + +/* Note: This doesn't put any conntrack and bridge info in dst. */ +static inline void __nf_copy(struct sk_buff *dst, const struct sk_buff *src, + bool copy) +{ +#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) + dst->nfct = src->nfct; + nf_conntrack_get(src->nfct); + if (copy) + dst->nfctinfo = src->nfctinfo; +#endif +#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER) + dst->nf_bridge = src->nf_bridge; + nf_bridge_get(src->nf_bridge); +#endif +#if IS_ENABLED(CONFIG_NETFILTER_XT_TARGET_TRACE) || defined(CONFIG_NF_TABLES) + if (copy) + dst->nf_trace = src->nf_trace; +#endif +} + +static inline void nf_copy(struct sk_buff *dst, const struct sk_buff *src) +{ +#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) + nf_conntrack_put(dst->nfct); +#endif +#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER) + nf_bridge_put(dst->nf_bridge); +#endif + __nf_copy(dst, src, true); +} + +#ifdef CONFIG_NETWORK_SECMARK +static inline void skb_copy_secmark(struct sk_buff *to, const struct sk_buff *from) +{ + to->secmark = from->secmark; +} + +static inline void skb_init_secmark(struct sk_buff *skb) +{ + skb->secmark = 0; +} +#else +static inline void skb_copy_secmark(struct sk_buff *to, const struct sk_buff *from) +{ } + +static inline void skb_init_secmark(struct sk_buff *skb) +{ } +#endif + +static inline bool skb_irq_freeable(const struct sk_buff *skb) +{ + return !skb->destructor && +#if IS_ENABLED(CONFIG_XFRM) + !skb->sp && +#endif +#if IS_ENABLED(CONFIG_NF_CONNTRACK) + !skb->nfct && +#endif + !skb->_skb_refdst && + !skb_has_frag_list(skb); +} + +static inline void skb_set_queue_mapping(struct sk_buff *skb, u16 queue_mapping) +{ + skb->queue_mapping = queue_mapping; +} + +static inline u16 skb_get_queue_mapping(const struct sk_buff *skb) +{ + return skb->queue_mapping; +} + +static inline void skb_copy_queue_mapping(struct sk_buff *to, const struct sk_buff *from) +{ + to->queue_mapping = from->queue_mapping; +} + +static inline void skb_record_rx_queue(struct sk_buff *skb, u16 rx_queue) +{ + skb->queue_mapping = rx_queue + 1; +} + +static inline u16 skb_get_rx_queue(const struct sk_buff *skb) +{ + return skb->queue_mapping - 1; +} + +static inline bool skb_rx_queue_recorded(const struct sk_buff *skb) +{ + return skb->queue_mapping != 0; +} + +u16 __skb_tx_hash(const struct net_device *dev, struct sk_buff *skb, + unsigned int num_tx_queues); + +static inline struct sec_path *skb_sec_path(struct sk_buff *skb) +{ +#ifdef CONFIG_XFRM + return skb->sp; +#else + return NULL; +#endif +} + +/* Keeps track of mac header offset relative to skb->head. + * It is useful for TSO of Tunneling protocol. e.g. GRE. + * For non-tunnel skb it points to skb_mac_header() and for + * tunnel skb it points to outer mac header. + * Keeps track of level of encapsulation of network headers. + */ +struct skb_gso_cb { + int mac_offset; + int encap_level; + __u16 csum_start; +}; +#define SKB_GSO_CB(skb) ((struct skb_gso_cb *)(skb)->cb) + +static inline int skb_tnl_header_len(const struct sk_buff *inner_skb) +{ + return (skb_mac_header(inner_skb) - inner_skb->head) - + SKB_GSO_CB(inner_skb)->mac_offset; +} + +static inline int gso_pskb_expand_head(struct sk_buff *skb, int extra) +{ + int new_headroom, headroom; + int ret; + + headroom = skb_headroom(skb); + ret = pskb_expand_head(skb, extra, 0, GFP_ATOMIC); + if (ret) + return ret; + + new_headroom = skb_headroom(skb); + SKB_GSO_CB(skb)->mac_offset += (new_headroom - headroom); + return 0; +} + +/* Compute the checksum for a gso segment. First compute the checksum value + * from the start of transport header to SKB_GSO_CB(skb)->csum_start, and + * then add in skb->csum (checksum from csum_start to end of packet). + * skb->csum and csum_start are then updated to reflect the checksum of the + * resultant packet starting from the transport header-- the resultant checksum + * is in the res argument (i.e. normally zero or ~ of checksum of a pseudo + * header. + */ +static inline __sum16 gso_make_checksum(struct sk_buff *skb, __wsum res) +{ + int plen = SKB_GSO_CB(skb)->csum_start - skb_headroom(skb) - + skb_transport_offset(skb); + __u16 csum; + + csum = csum_fold(csum_partial(skb_transport_header(skb), + plen, skb->csum)); + skb->csum = res; + SKB_GSO_CB(skb)->csum_start -= plen; + + return csum; +} + +static inline bool skb_is_gso(const struct sk_buff *skb) +{ + return skb_shinfo(skb)->gso_size; +} + +/* Note: Should be called only if skb_is_gso(skb) is true */ +static inline bool skb_is_gso_v6(const struct sk_buff *skb) +{ + return skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6; +} + +void __skb_warn_lro_forwarding(const struct sk_buff *skb); + +static inline bool skb_warn_if_lro(const struct sk_buff *skb) +{ + /* LRO sets gso_size but not gso_type, whereas if GSO is really + * wanted then gso_type will be set. */ + const struct skb_shared_info *shinfo = skb_shinfo(skb); + + if (skb_is_nonlinear(skb) && shinfo->gso_size != 0 && + unlikely(shinfo->gso_type == 0)) { + __skb_warn_lro_forwarding(skb); + return true; + } + return false; +} + +static inline void skb_forward_csum(struct sk_buff *skb) +{ + /* Unfortunately we don't support this one. Any brave souls? */ + if (skb->ip_summed == CHECKSUM_COMPLETE) + skb->ip_summed = CHECKSUM_NONE; +} + +/** + * skb_checksum_none_assert - make sure skb ip_summed is CHECKSUM_NONE + * @skb: skb to check + * + * fresh skbs have their ip_summed set to CHECKSUM_NONE. + * Instead of forcing ip_summed to CHECKSUM_NONE, we can + * use this helper, to document places where we make this assertion. + */ +static inline void skb_checksum_none_assert(const struct sk_buff *skb) +{ +#ifdef DEBUG + BUG_ON(skb->ip_summed != CHECKSUM_NONE); +#endif +} + +bool skb_partial_csum_set(struct sk_buff *skb, u16 start, u16 off); + +int skb_checksum_setup(struct sk_buff *skb, bool recalculate); + +u32 skb_get_poff(const struct sk_buff *skb); +u32 __skb_get_poff(const struct sk_buff *skb, void *data, + const struct flow_keys *keys, int hlen); + +/** + * skb_head_is_locked - Determine if the skb->head is locked down + * @skb: skb to check + * + * The head on skbs build around a head frag can be removed if they are + * not cloned. This function returns true if the skb head is locked down + * due to either being allocated via kmalloc, or by being a clone with + * multiple references to the head. + */ +static inline bool skb_head_is_locked(const struct sk_buff *skb) +{ + return !skb->head_frag || skb_cloned(skb); +} + +/** + * skb_gso_network_seglen - Return length of individual segments of a gso packet + * + * @skb: GSO skb + * + * skb_gso_network_seglen is used to determine the real size of the + * individual segments, including Layer3 (IP, IPv6) and L4 headers (TCP/UDP). + * + * The MAC/L2 header is not accounted for. + */ +static inline unsigned int skb_gso_network_seglen(const struct sk_buff *skb) +{ + unsigned int hdr_len = skb_transport_header(skb) - + skb_network_header(skb); + return hdr_len + skb_gso_transport_seglen(skb); +} +#endif /* __KERNEL__ */ +#endif /* _LINUX_SKBUFF_H */ diff -Nur linux-3.18.14.orig/include/linux/smp.h linux-3.18.14-rt/include/linux/smp.h --- linux-3.18.14.orig/include/linux/smp.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/smp.h 2015-05-31 15:32:48.405635367 -0500 @@ -178,6 +178,9 @@ #define get_cpu() ({ preempt_disable(); smp_processor_id(); }) #define put_cpu() preempt_enable() +#define get_cpu_light() ({ migrate_disable(); smp_processor_id(); }) +#define put_cpu_light() migrate_enable() + /* * Callback to arch code if there's nosmp or maxcpus=0 on the * boot command line: diff -Nur linux-3.18.14.orig/include/linux/spinlock_api_smp.h linux-3.18.14-rt/include/linux/spinlock_api_smp.h --- linux-3.18.14.orig/include/linux/spinlock_api_smp.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/spinlock_api_smp.h 2015-05-31 15:32:48.409635367 -0500 @@ -187,6 +187,8 @@ return 0; } -#include +#ifndef CONFIG_PREEMPT_RT_FULL +# include +#endif #endif /* __LINUX_SPINLOCK_API_SMP_H */ diff -Nur linux-3.18.14.orig/include/linux/spinlock.h linux-3.18.14-rt/include/linux/spinlock.h --- linux-3.18.14.orig/include/linux/spinlock.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/spinlock.h 2015-05-31 15:32:48.405635367 -0500 @@ -278,7 +278,11 @@ #define raw_spin_can_lock(lock) (!raw_spin_is_locked(lock)) /* Include rwlock functions */ -#include +#ifdef CONFIG_PREEMPT_RT_FULL +# include +#else +# include +#endif /* * Pull the _spin_*()/_read_*()/_write_*() functions/declarations: @@ -289,6 +293,10 @@ # include #endif +#ifdef CONFIG_PREEMPT_RT_FULL +# include +#else /* PREEMPT_RT_FULL */ + /* * Map the spin_lock functions to the raw variants for PREEMPT_RT=n */ @@ -418,4 +426,6 @@ #define atomic_dec_and_lock(atomic, lock) \ __cond_lock(lock, _atomic_dec_and_lock(atomic, lock)) +#endif /* !PREEMPT_RT_FULL */ + #endif /* __LINUX_SPINLOCK_H */ diff -Nur linux-3.18.14.orig/include/linux/spinlock_rt.h linux-3.18.14-rt/include/linux/spinlock_rt.h --- linux-3.18.14.orig/include/linux/spinlock_rt.h 1969-12-31 18:00:00.000000000 -0600 +++ linux-3.18.14-rt/include/linux/spinlock_rt.h 2015-05-31 15:32:48.413635367 -0500 @@ -0,0 +1,167 @@ +#ifndef __LINUX_SPINLOCK_RT_H +#define __LINUX_SPINLOCK_RT_H + +#ifndef __LINUX_SPINLOCK_H +#error Do not include directly. Use spinlock.h +#endif + +#include + +extern void +__rt_spin_lock_init(spinlock_t *lock, char *name, struct lock_class_key *key); + +#define spin_lock_init(slock) \ +do { \ + static struct lock_class_key __key; \ + \ + rt_mutex_init(&(slock)->lock); \ + __rt_spin_lock_init(slock, #slock, &__key); \ +} while (0) + +extern void __lockfunc rt_spin_lock(spinlock_t *lock); +extern unsigned long __lockfunc rt_spin_lock_trace_flags(spinlock_t *lock); +extern void __lockfunc rt_spin_lock_nested(spinlock_t *lock, int subclass); +extern void __lockfunc rt_spin_unlock(spinlock_t *lock); +extern void __lockfunc rt_spin_unlock_after_trylock_in_irq(spinlock_t *lock); +extern void __lockfunc rt_spin_unlock_wait(spinlock_t *lock); +extern int __lockfunc rt_spin_trylock_irqsave(spinlock_t *lock, unsigned long *flags); +extern int __lockfunc rt_spin_trylock_bh(spinlock_t *lock); +extern int __lockfunc rt_spin_trylock(spinlock_t *lock); +extern int atomic_dec_and_spin_lock(atomic_t *atomic, spinlock_t *lock); + +/* + * lockdep-less calls, for derived types like rwlock: + * (for trylock they can use rt_mutex_trylock() directly. + */ +extern void __lockfunc __rt_spin_lock(struct rt_mutex *lock); +extern void __lockfunc __rt_spin_unlock(struct rt_mutex *lock); +extern int __lockfunc __rt_spin_trylock(struct rt_mutex *lock); + +#define spin_lock(lock) \ + do { \ + migrate_disable(); \ + rt_spin_lock(lock); \ + } while (0) + +#define spin_lock_bh(lock) \ + do { \ + local_bh_disable(); \ + migrate_disable(); \ + rt_spin_lock(lock); \ + } while (0) + +#define spin_lock_irq(lock) spin_lock(lock) + +#define spin_do_trylock(lock) __cond_lock(lock, rt_spin_trylock(lock)) + +#define spin_trylock(lock) \ +({ \ + int __locked; \ + migrate_disable(); \ + __locked = spin_do_trylock(lock); \ + if (!__locked) \ + migrate_enable(); \ + __locked; \ +}) + +#ifdef CONFIG_LOCKDEP +# define spin_lock_nested(lock, subclass) \ + do { \ + migrate_disable(); \ + rt_spin_lock_nested(lock, subclass); \ + } while (0) + +# define spin_lock_irqsave_nested(lock, flags, subclass) \ + do { \ + typecheck(unsigned long, flags); \ + flags = 0; \ + migrate_disable(); \ + rt_spin_lock_nested(lock, subclass); \ + } while (0) +#else +# define spin_lock_nested(lock, subclass) spin_lock(lock) + +# define spin_lock_irqsave_nested(lock, flags, subclass) \ + do { \ + typecheck(unsigned long, flags); \ + flags = 0; \ + spin_lock(lock); \ + } while (0) +#endif + +#define spin_lock_irqsave(lock, flags) \ + do { \ + typecheck(unsigned long, flags); \ + flags = 0; \ + spin_lock(lock); \ + } while (0) + +static inline unsigned long spin_lock_trace_flags(spinlock_t *lock) +{ + unsigned long flags = 0; +#ifdef CONFIG_TRACE_IRQFLAGS + flags = rt_spin_lock_trace_flags(lock); +#else + spin_lock(lock); /* lock_local */ +#endif + return flags; +} + +/* FIXME: we need rt_spin_lock_nest_lock */ +#define spin_lock_nest_lock(lock, nest_lock) spin_lock_nested(lock, 0) + +#define spin_unlock(lock) \ + do { \ + rt_spin_unlock(lock); \ + migrate_enable(); \ + } while (0) + +#define spin_unlock_bh(lock) \ + do { \ + rt_spin_unlock(lock); \ + migrate_enable(); \ + local_bh_enable(); \ + } while (0) + +#define spin_unlock_irq(lock) spin_unlock(lock) + +#define spin_unlock_irqrestore(lock, flags) \ + do { \ + typecheck(unsigned long, flags); \ + (void) flags; \ + spin_unlock(lock); \ + } while (0) + +#define spin_trylock_bh(lock) __cond_lock(lock, rt_spin_trylock_bh(lock)) +#define spin_trylock_irq(lock) spin_trylock(lock) + +#define spin_trylock_irqsave(lock, flags) \ + rt_spin_trylock_irqsave(lock, &(flags)) + +#define spin_unlock_wait(lock) rt_spin_unlock_wait(lock) + +#ifdef CONFIG_GENERIC_LOCKBREAK +# define spin_is_contended(lock) ((lock)->break_lock) +#else +# define spin_is_contended(lock) (((void)(lock), 0)) +#endif + +static inline int spin_can_lock(spinlock_t *lock) +{ + return !rt_mutex_is_locked(&lock->lock); +} + +static inline int spin_is_locked(spinlock_t *lock) +{ + return rt_mutex_is_locked(&lock->lock); +} + +static inline void assert_spin_locked(spinlock_t *lock) +{ + BUG_ON(!spin_is_locked(lock)); +} + +#define atomic_dec_and_lock(atomic, lock) \ + atomic_dec_and_spin_lock(atomic, lock) + +#endif diff -Nur linux-3.18.14.orig/include/linux/spinlock_types.h linux-3.18.14-rt/include/linux/spinlock_types.h --- linux-3.18.14.orig/include/linux/spinlock_types.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/spinlock_types.h 2015-05-31 15:32:48.413635367 -0500 @@ -9,80 +9,15 @@ * Released under the General Public License (GPL). */ -#if defined(CONFIG_SMP) -# include -#else -# include -#endif - -#include - -typedef struct raw_spinlock { - arch_spinlock_t raw_lock; -#ifdef CONFIG_GENERIC_LOCKBREAK - unsigned int break_lock; -#endif -#ifdef CONFIG_DEBUG_SPINLOCK - unsigned int magic, owner_cpu; - void *owner; -#endif -#ifdef CONFIG_DEBUG_LOCK_ALLOC - struct lockdep_map dep_map; -#endif -} raw_spinlock_t; - -#define SPINLOCK_MAGIC 0xdead4ead - -#define SPINLOCK_OWNER_INIT ((void *)-1L) - -#ifdef CONFIG_DEBUG_LOCK_ALLOC -# define SPIN_DEP_MAP_INIT(lockname) .dep_map = { .name = #lockname } -#else -# define SPIN_DEP_MAP_INIT(lockname) -#endif +#include -#ifdef CONFIG_DEBUG_SPINLOCK -# define SPIN_DEBUG_INIT(lockname) \ - .magic = SPINLOCK_MAGIC, \ - .owner_cpu = -1, \ - .owner = SPINLOCK_OWNER_INIT, +#ifndef CONFIG_PREEMPT_RT_FULL +# include +# include #else -# define SPIN_DEBUG_INIT(lockname) +# include +# include +# include #endif -#define __RAW_SPIN_LOCK_INITIALIZER(lockname) \ - { \ - .raw_lock = __ARCH_SPIN_LOCK_UNLOCKED, \ - SPIN_DEBUG_INIT(lockname) \ - SPIN_DEP_MAP_INIT(lockname) } - -#define __RAW_SPIN_LOCK_UNLOCKED(lockname) \ - (raw_spinlock_t) __RAW_SPIN_LOCK_INITIALIZER(lockname) - -#define DEFINE_RAW_SPINLOCK(x) raw_spinlock_t x = __RAW_SPIN_LOCK_UNLOCKED(x) - -typedef struct spinlock { - union { - struct raw_spinlock rlock; - -#ifdef CONFIG_DEBUG_LOCK_ALLOC -# define LOCK_PADSIZE (offsetof(struct raw_spinlock, dep_map)) - struct { - u8 __padding[LOCK_PADSIZE]; - struct lockdep_map dep_map; - }; -#endif - }; -} spinlock_t; - -#define __SPIN_LOCK_INITIALIZER(lockname) \ - { { .rlock = __RAW_SPIN_LOCK_INITIALIZER(lockname) } } - -#define __SPIN_LOCK_UNLOCKED(lockname) \ - (spinlock_t ) __SPIN_LOCK_INITIALIZER(lockname) - -#define DEFINE_SPINLOCK(x) spinlock_t x = __SPIN_LOCK_UNLOCKED(x) - -#include - #endif /* __LINUX_SPINLOCK_TYPES_H */ diff -Nur linux-3.18.14.orig/include/linux/spinlock_types_nort.h linux-3.18.14-rt/include/linux/spinlock_types_nort.h --- linux-3.18.14.orig/include/linux/spinlock_types_nort.h 1969-12-31 18:00:00.000000000 -0600 +++ linux-3.18.14-rt/include/linux/spinlock_types_nort.h 2015-05-31 15:32:48.413635367 -0500 @@ -0,0 +1,33 @@ +#ifndef __LINUX_SPINLOCK_TYPES_NORT_H +#define __LINUX_SPINLOCK_TYPES_NORT_H + +#ifndef __LINUX_SPINLOCK_TYPES_H +#error "Do not include directly. Include spinlock_types.h instead" +#endif + +/* + * The non RT version maps spinlocks to raw_spinlocks + */ +typedef struct spinlock { + union { + struct raw_spinlock rlock; + +#ifdef CONFIG_DEBUG_LOCK_ALLOC +# define LOCK_PADSIZE (offsetof(struct raw_spinlock, dep_map)) + struct { + u8 __padding[LOCK_PADSIZE]; + struct lockdep_map dep_map; + }; +#endif + }; +} spinlock_t; + +#define __SPIN_LOCK_INITIALIZER(lockname) \ + { { .rlock = __RAW_SPIN_LOCK_INITIALIZER(lockname) } } + +#define __SPIN_LOCK_UNLOCKED(lockname) \ + (spinlock_t ) __SPIN_LOCK_INITIALIZER(lockname) + +#define DEFINE_SPINLOCK(x) spinlock_t x = __SPIN_LOCK_UNLOCKED(x) + +#endif diff -Nur linux-3.18.14.orig/include/linux/spinlock_types_raw.h linux-3.18.14-rt/include/linux/spinlock_types_raw.h --- linux-3.18.14.orig/include/linux/spinlock_types_raw.h 1969-12-31 18:00:00.000000000 -0600 +++ linux-3.18.14-rt/include/linux/spinlock_types_raw.h 2015-05-31 15:32:48.413635367 -0500 @@ -0,0 +1,56 @@ +#ifndef __LINUX_SPINLOCK_TYPES_RAW_H +#define __LINUX_SPINLOCK_TYPES_RAW_H + +#if defined(CONFIG_SMP) +# include +#else +# include +#endif + +#include + +typedef struct raw_spinlock { + arch_spinlock_t raw_lock; +#ifdef CONFIG_GENERIC_LOCKBREAK + unsigned int break_lock; +#endif +#ifdef CONFIG_DEBUG_SPINLOCK + unsigned int magic, owner_cpu; + void *owner; +#endif +#ifdef CONFIG_DEBUG_LOCK_ALLOC + struct lockdep_map dep_map; +#endif +} raw_spinlock_t; + +#define SPINLOCK_MAGIC 0xdead4ead + +#define SPINLOCK_OWNER_INIT ((void *)-1L) + +#ifdef CONFIG_DEBUG_LOCK_ALLOC +# define SPIN_DEP_MAP_INIT(lockname) .dep_map = { .name = #lockname } +#else +# define SPIN_DEP_MAP_INIT(lockname) +#endif + +#ifdef CONFIG_DEBUG_SPINLOCK +# define SPIN_DEBUG_INIT(lockname) \ + .magic = SPINLOCK_MAGIC, \ + .owner_cpu = -1, \ + .owner = SPINLOCK_OWNER_INIT, +#else +# define SPIN_DEBUG_INIT(lockname) +#endif + +#define __RAW_SPIN_LOCK_INITIALIZER(lockname) \ + { \ + .raw_lock = __ARCH_SPIN_LOCK_UNLOCKED, \ + SPIN_DEBUG_INIT(lockname) \ + SPIN_DEP_MAP_INIT(lockname) } + +#define __RAW_SPIN_LOCK_UNLOCKED(lockname) \ + (raw_spinlock_t) __RAW_SPIN_LOCK_INITIALIZER(lockname) + +#define DEFINE_RAW_SPINLOCK(x) raw_spinlock_t x = __RAW_SPIN_LOCK_UNLOCKED(x) + +#endif diff -Nur linux-3.18.14.orig/include/linux/spinlock_types_rt.h linux-3.18.14-rt/include/linux/spinlock_types_rt.h --- linux-3.18.14.orig/include/linux/spinlock_types_rt.h 1969-12-31 18:00:00.000000000 -0600 +++ linux-3.18.14-rt/include/linux/spinlock_types_rt.h 2015-05-31 15:32:48.413635367 -0500 @@ -0,0 +1,51 @@ +#ifndef __LINUX_SPINLOCK_TYPES_RT_H +#define __LINUX_SPINLOCK_TYPES_RT_H + +#ifndef __LINUX_SPINLOCK_TYPES_H +#error "Do not include directly. Include spinlock_types.h instead" +#endif + +#include + +/* + * PREEMPT_RT: spinlocks - an RT mutex plus lock-break field: + */ +typedef struct spinlock { + struct rt_mutex lock; + unsigned int break_lock; +#ifdef CONFIG_DEBUG_LOCK_ALLOC + struct lockdep_map dep_map; +#endif +} spinlock_t; + +#ifdef CONFIG_DEBUG_RT_MUTEXES +# define __RT_SPIN_INITIALIZER(name) \ + { \ + .wait_lock = __RAW_SPIN_LOCK_UNLOCKED(name.wait_lock), \ + .save_state = 1, \ + .file = __FILE__, \ + .line = __LINE__ , \ + } +#else +# define __RT_SPIN_INITIALIZER(name) \ + { \ + .wait_lock = __RAW_SPIN_LOCK_UNLOCKED(name.wait_lock), \ + .save_state = 1, \ + } +#endif + +/* +.wait_list = PLIST_HEAD_INIT_RAW((name).lock.wait_list, (name).lock.wait_lock) +*/ + +#define __SPIN_LOCK_UNLOCKED(name) \ + { .lock = __RT_SPIN_INITIALIZER(name.lock), \ + SPIN_DEP_MAP_INIT(name) } + +#define __DEFINE_SPINLOCK(name) \ + spinlock_t name = __SPIN_LOCK_UNLOCKED(name) + +#define DEFINE_SPINLOCK(name) \ + spinlock_t name __cacheline_aligned_in_smp = __SPIN_LOCK_UNLOCKED(name) + +#endif diff -Nur linux-3.18.14.orig/include/linux/srcu.h linux-3.18.14-rt/include/linux/srcu.h --- linux-3.18.14.orig/include/linux/srcu.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/srcu.h 2015-05-31 15:32:48.445635367 -0500 @@ -84,10 +84,10 @@ void process_srcu(struct work_struct *work); -#define __SRCU_STRUCT_INIT(name) \ +#define __SRCU_STRUCT_INIT(name, pcpu_name) \ { \ .completed = -300, \ - .per_cpu_ref = &name##_srcu_array, \ + .per_cpu_ref = &pcpu_name, \ .queue_lock = __SPIN_LOCK_UNLOCKED(name.queue_lock), \ .running = false, \ .batch_queue = RCU_BATCH_INIT(name.batch_queue), \ @@ -104,11 +104,12 @@ */ #define DEFINE_SRCU(name) \ static DEFINE_PER_CPU(struct srcu_struct_array, name##_srcu_array);\ - struct srcu_struct name = __SRCU_STRUCT_INIT(name); + struct srcu_struct name = __SRCU_STRUCT_INIT(name, name##_srcu_array); #define DEFINE_STATIC_SRCU(name) \ static DEFINE_PER_CPU(struct srcu_struct_array, name##_srcu_array);\ - static struct srcu_struct name = __SRCU_STRUCT_INIT(name); + static struct srcu_struct name = __SRCU_STRUCT_INIT(\ + name, name##_srcu_array); /** * call_srcu() - Queue a callback for invocation after an SRCU grace period diff -Nur linux-3.18.14.orig/include/linux/swap.h linux-3.18.14-rt/include/linux/swap.h --- linux-3.18.14.orig/include/linux/swap.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/swap.h 2015-05-31 15:32:48.449635367 -0500 @@ -11,6 +11,7 @@ #include #include #include +#include #include struct notifier_block; @@ -260,7 +261,8 @@ void *workingset_eviction(struct address_space *mapping, struct page *page); bool workingset_refault(void *shadow); void workingset_activation(struct page *page); -extern struct list_lru workingset_shadow_nodes; +extern struct list_lru __workingset_shadow_nodes; +DECLARE_LOCAL_IRQ_LOCK(workingset_shadow_lock); static inline unsigned int workingset_node_pages(struct radix_tree_node *node) { diff -Nur linux-3.18.14.orig/include/linux/sysctl.h linux-3.18.14-rt/include/linux/sysctl.h --- linux-3.18.14.orig/include/linux/sysctl.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/sysctl.h 2015-05-31 15:32:48.449635367 -0500 @@ -25,6 +25,7 @@ #include #include #include +#include #include /* For the /proc/sys support */ diff -Nur linux-3.18.14.orig/include/linux/thread_info.h linux-3.18.14-rt/include/linux/thread_info.h --- linux-3.18.14.orig/include/linux/thread_info.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/thread_info.h 2015-05-31 15:32:48.449635367 -0500 @@ -102,7 +102,17 @@ #define test_thread_flag(flag) \ test_ti_thread_flag(current_thread_info(), flag) -#define tif_need_resched() test_thread_flag(TIF_NEED_RESCHED) +#ifdef CONFIG_PREEMPT_LAZY +#define tif_need_resched() (test_thread_flag(TIF_NEED_RESCHED) || \ + test_thread_flag(TIF_NEED_RESCHED_LAZY)) +#define tif_need_resched_now() (test_thread_flag(TIF_NEED_RESCHED)) +#define tif_need_resched_lazy() test_thread_flag(TIF_NEED_RESCHED_LAZY)) + +#else +#define tif_need_resched() test_thread_flag(TIF_NEED_RESCHED) +#define tif_need_resched_now() test_thread_flag(TIF_NEED_RESCHED) +#define tif_need_resched_lazy() 0 +#endif #if defined TIF_RESTORE_SIGMASK && !defined HAVE_SET_RESTORE_SIGMASK /* diff -Nur linux-3.18.14.orig/include/linux/timer.h linux-3.18.14-rt/include/linux/timer.h --- linux-3.18.14.orig/include/linux/timer.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/timer.h 2015-05-31 15:32:48.449635367 -0500 @@ -241,7 +241,7 @@ extern int try_to_del_timer_sync(struct timer_list *timer); -#ifdef CONFIG_SMP +#if defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT_FULL) extern int del_timer_sync(struct timer_list *timer); #else # define del_timer_sync(t) del_timer(t) diff -Nur linux-3.18.14.orig/include/linux/uaccess.h linux-3.18.14-rt/include/linux/uaccess.h --- linux-3.18.14.orig/include/linux/uaccess.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/uaccess.h 2015-05-31 15:32:48.449635367 -0500 @@ -6,14 +6,9 @@ /* * These routines enable/disable the pagefault handler in that - * it will not take any locks and go straight to the fixup table. - * - * They have great resemblance to the preempt_disable/enable calls - * and in fact they are identical; this is because currently there is - * no other way to make the pagefault handlers do this. So we do - * disable preemption but we don't necessarily care about that. + * it will not take any MM locks and go straight to the fixup table. */ -static inline void pagefault_disable(void) +static inline void raw_pagefault_disable(void) { preempt_count_inc(); /* @@ -23,7 +18,7 @@ barrier(); } -static inline void pagefault_enable(void) +static inline void raw_pagefault_enable(void) { #ifndef CONFIG_PREEMPT /* @@ -37,6 +32,21 @@ #endif } +#ifndef CONFIG_PREEMPT_RT_FULL +static inline void pagefault_disable(void) +{ + raw_pagefault_disable(); +} + +static inline void pagefault_enable(void) +{ + raw_pagefault_enable(); +} +#else +extern void pagefault_disable(void); +extern void pagefault_enable(void); +#endif + #ifndef ARCH_HAS_NOCACHE_UACCESS static inline unsigned long __copy_from_user_inatomic_nocache(void *to, @@ -76,9 +86,9 @@ mm_segment_t old_fs = get_fs(); \ \ set_fs(KERNEL_DS); \ - pagefault_disable(); \ + raw_pagefault_disable(); \ ret = __copy_from_user_inatomic(&(retval), (__force typeof(retval) __user *)(addr), sizeof(retval)); \ - pagefault_enable(); \ + raw_pagefault_enable(); \ set_fs(old_fs); \ ret; \ }) diff -Nur linux-3.18.14.orig/include/linux/uprobes.h linux-3.18.14-rt/include/linux/uprobes.h --- linux-3.18.14.orig/include/linux/uprobes.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/uprobes.h 2015-05-31 15:32:48.481635367 -0500 @@ -27,6 +27,7 @@ #include #include #include +#include struct vm_area_struct; struct mm_struct; diff -Nur linux-3.18.14.orig/include/linux/vmstat.h linux-3.18.14-rt/include/linux/vmstat.h --- linux-3.18.14.orig/include/linux/vmstat.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/vmstat.h 2015-05-31 15:32:48.481635367 -0500 @@ -33,7 +33,9 @@ */ static inline void __count_vm_event(enum vm_event_item item) { + preempt_disable_rt(); raw_cpu_inc(vm_event_states.event[item]); + preempt_enable_rt(); } static inline void count_vm_event(enum vm_event_item item) @@ -43,7 +45,9 @@ static inline void __count_vm_events(enum vm_event_item item, long delta) { + preempt_disable_rt(); raw_cpu_add(vm_event_states.event[item], delta); + preempt_enable_rt(); } static inline void count_vm_events(enum vm_event_item item, long delta) diff -Nur linux-3.18.14.orig/include/linux/wait.h linux-3.18.14-rt/include/linux/wait.h --- linux-3.18.14.orig/include/linux/wait.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/linux/wait.h 2015-05-31 15:32:48.481635367 -0500 @@ -8,6 +8,7 @@ #include #include #include +#include typedef struct __wait_queue wait_queue_t; typedef int (*wait_queue_func_t)(wait_queue_t *wait, unsigned mode, int flags, void *key); diff -Nur linux-3.18.14.orig/include/linux/wait-simple.h linux-3.18.14-rt/include/linux/wait-simple.h --- linux-3.18.14.orig/include/linux/wait-simple.h 1969-12-31 18:00:00.000000000 -0600 +++ linux-3.18.14-rt/include/linux/wait-simple.h 2015-05-31 15:32:48.481635367 -0500 @@ -0,0 +1,207 @@ +#ifndef _LINUX_WAIT_SIMPLE_H +#define _LINUX_WAIT_SIMPLE_H + +#include +#include + +#include + +struct swaiter { + struct task_struct *task; + struct list_head node; +}; + +#define DEFINE_SWAITER(name) \ + struct swaiter name = { \ + .task = current, \ + .node = LIST_HEAD_INIT((name).node), \ + } + +struct swait_head { + raw_spinlock_t lock; + struct list_head list; +}; + +#define SWAIT_HEAD_INITIALIZER(name) { \ + .lock = __RAW_SPIN_LOCK_UNLOCKED(name.lock), \ + .list = LIST_HEAD_INIT((name).list), \ + } + +#define DEFINE_SWAIT_HEAD(name) \ + struct swait_head name = SWAIT_HEAD_INITIALIZER(name) + +extern void __init_swait_head(struct swait_head *h, struct lock_class_key *key); + +#define init_swait_head(swh) \ + do { \ + static struct lock_class_key __key; \ + \ + __init_swait_head((swh), &__key); \ + } while (0) + +/* + * Waiter functions + */ +extern void swait_prepare_locked(struct swait_head *head, struct swaiter *w); +extern void swait_prepare(struct swait_head *head, struct swaiter *w, int state); +extern void swait_finish_locked(struct swait_head *head, struct swaiter *w); +extern void swait_finish(struct swait_head *head, struct swaiter *w); + +/* Check whether a head has waiters enqueued */ +static inline bool swaitqueue_active(struct swait_head *h) +{ + /* Make sure the condition is visible before checking list_empty() */ + smp_mb(); + return !list_empty(&h->list); +} + +/* + * Wakeup functions + */ +extern unsigned int __swait_wake(struct swait_head *head, unsigned int state, unsigned int num); +extern unsigned int __swait_wake_locked(struct swait_head *head, unsigned int state, unsigned int num); + +#define swait_wake(head) __swait_wake(head, TASK_NORMAL, 1) +#define swait_wake_interruptible(head) __swait_wake(head, TASK_INTERRUPTIBLE, 1) +#define swait_wake_all(head) __swait_wake(head, TASK_NORMAL, 0) +#define swait_wake_all_interruptible(head) __swait_wake(head, TASK_INTERRUPTIBLE, 0) + +/* + * Event API + */ +#define __swait_event(wq, condition) \ +do { \ + DEFINE_SWAITER(__wait); \ + \ + for (;;) { \ + swait_prepare(&wq, &__wait, TASK_UNINTERRUPTIBLE); \ + if (condition) \ + break; \ + schedule(); \ + } \ + swait_finish(&wq, &__wait); \ +} while (0) + +/** + * swait_event - sleep until a condition gets true + * @wq: the waitqueue to wait on + * @condition: a C expression for the event to wait for + * + * The process is put to sleep (TASK_UNINTERRUPTIBLE) until the + * @condition evaluates to true. The @condition is checked each time + * the waitqueue @wq is woken up. + * + * wake_up() has to be called after changing any variable that could + * change the result of the wait condition. + */ +#define swait_event(wq, condition) \ +do { \ + if (condition) \ + break; \ + __swait_event(wq, condition); \ +} while (0) + +#define __swait_event_interruptible(wq, condition, ret) \ +do { \ + DEFINE_SWAITER(__wait); \ + \ + for (;;) { \ + swait_prepare(&wq, &__wait, TASK_INTERRUPTIBLE); \ + if (condition) \ + break; \ + if (signal_pending(current)) { \ + ret = -ERESTARTSYS; \ + break; \ + } \ + schedule(); \ + } \ + swait_finish(&wq, &__wait); \ +} while (0) + +#define __swait_event_interruptible_timeout(wq, condition, ret) \ +do { \ + DEFINE_SWAITER(__wait); \ + \ + for (;;) { \ + swait_prepare(&wq, &__wait, TASK_INTERRUPTIBLE); \ + if (condition) \ + break; \ + if (signal_pending(current)) { \ + ret = -ERESTARTSYS; \ + break; \ + } \ + ret = schedule_timeout(ret); \ + if (!ret) \ + break; \ + } \ + swait_finish(&wq, &__wait); \ +} while (0) + +/** + * swait_event_interruptible - sleep until a condition gets true + * @wq: the waitqueue to wait on + * @condition: a C expression for the event to wait for + * + * The process is put to sleep (TASK_INTERRUPTIBLE) until the + * @condition evaluates to true. The @condition is checked each time + * the waitqueue @wq is woken up. + * + * wake_up() has to be called after changing any variable that could + * change the result of the wait condition. + */ +#define swait_event_interruptible(wq, condition) \ +({ \ + int __ret = 0; \ + if (!(condition)) \ + __swait_event_interruptible(wq, condition, __ret); \ + __ret; \ +}) + +#define swait_event_interruptible_timeout(wq, condition, timeout) \ +({ \ + int __ret = timeout; \ + if (!(condition)) \ + __swait_event_interruptible_timeout(wq, condition, __ret); \ + __ret; \ +}) + +#define __swait_event_timeout(wq, condition, ret) \ +do { \ + DEFINE_SWAITER(__wait); \ + \ + for (;;) { \ + swait_prepare(&wq, &__wait, TASK_UNINTERRUPTIBLE); \ + if (condition) \ + break; \ + ret = schedule_timeout(ret); \ + if (!ret) \ + break; \ + } \ + swait_finish(&wq, &__wait); \ +} while (0) + +/** + * swait_event_timeout - sleep until a condition gets true or a timeout elapses + * @wq: the waitqueue to wait on + * @condition: a C expression for the event to wait for + * @timeout: timeout, in jiffies + * + * The process is put to sleep (TASK_UNINTERRUPTIBLE) until the + * @condition evaluates to true. The @condition is checked each time + * the waitqueue @wq is woken up. + * + * wake_up() has to be called after changing any variable that could + * change the result of the wait condition. + * + * The function returns 0 if the @timeout elapsed, and the remaining + * jiffies if the condition evaluated to true before the timeout elapsed. + */ +#define swait_event_timeout(wq, condition, timeout) \ +({ \ + long __ret = timeout; \ + if (!(condition)) \ + __swait_event_timeout(wq, condition, __ret); \ + __ret; \ +}) + +#endif diff -Nur linux-3.18.14.orig/include/linux/work-simple.h linux-3.18.14-rt/include/linux/work-simple.h --- linux-3.18.14.orig/include/linux/work-simple.h 1969-12-31 18:00:00.000000000 -0600 +++ linux-3.18.14-rt/include/linux/work-simple.h 2015-05-31 15:32:48.481635367 -0500 @@ -0,0 +1,24 @@ +#ifndef _LINUX_SWORK_H +#define _LINUX_SWORK_H + +#include + +struct swork_event { + struct list_head item; + unsigned long flags; + void (*func)(struct swork_event *); +}; + +static inline void INIT_SWORK(struct swork_event *event, + void (*func)(struct swork_event *)) +{ + event->flags = 0; + event->func = func; +} + +bool swork_queue(struct swork_event *sev); + +int swork_get(void); +void swork_put(void); + +#endif /* _LINUX_SWORK_H */ diff -Nur linux-3.18.14.orig/include/net/dst.h linux-3.18.14-rt/include/net/dst.h --- linux-3.18.14.orig/include/net/dst.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/net/dst.h 2015-05-31 15:32:48.497635366 -0500 @@ -403,7 +403,7 @@ static inline int dst_neigh_output(struct dst_entry *dst, struct neighbour *n, struct sk_buff *skb) { - const struct hh_cache *hh; + struct hh_cache *hh; if (dst->pending_confirm) { unsigned long now = jiffies; diff -Nur linux-3.18.14.orig/include/net/neighbour.h linux-3.18.14-rt/include/net/neighbour.h --- linux-3.18.14.orig/include/net/neighbour.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/net/neighbour.h 2015-05-31 15:32:48.521635366 -0500 @@ -387,7 +387,7 @@ } #endif -static inline int neigh_hh_output(const struct hh_cache *hh, struct sk_buff *skb) +static inline int neigh_hh_output(struct hh_cache *hh, struct sk_buff *skb) { unsigned int seq; int hh_len; @@ -442,7 +442,7 @@ #define NEIGH_CB(skb) ((struct neighbour_cb *)(skb)->cb) -static inline void neigh_ha_snapshot(char *dst, const struct neighbour *n, +static inline void neigh_ha_snapshot(char *dst, struct neighbour *n, const struct net_device *dev) { unsigned int seq; diff -Nur linux-3.18.14.orig/include/net/netns/ipv4.h linux-3.18.14-rt/include/net/netns/ipv4.h --- linux-3.18.14.orig/include/net/netns/ipv4.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/include/net/netns/ipv4.h 2015-05-31 15:32:48.521635366 -0500 @@ -67,6 +67,7 @@ int sysctl_icmp_echo_ignore_all; int sysctl_icmp_echo_ignore_broadcasts; + int sysctl_icmp_echo_sysrq; int sysctl_icmp_ignore_bogus_error_responses; int sysctl_icmp_ratelimit; int sysctl_icmp_ratemask; diff -Nur linux-3.18.14.orig/include/trace/events/hist.h linux-3.18.14-rt/include/trace/events/hist.h --- linux-3.18.14.orig/include/trace/events/hist.h 1969-12-31 18:00:00.000000000 -0600 +++ linux-3.18.14-rt/include/trace/events/hist.h 2015-05-31 15:32:48.521635366 -0500 @@ -0,0 +1,72 @@ +#undef TRACE_SYSTEM +#define TRACE_SYSTEM hist + +#if !defined(_TRACE_HIST_H) || defined(TRACE_HEADER_MULTI_READ) +#define _TRACE_HIST_H + +#include "latency_hist.h" +#include + +#if !defined(CONFIG_PREEMPT_OFF_HIST) && !defined(CONFIG_INTERRUPT_OFF_HIST) +#define trace_preemptirqsoff_hist(a, b) +#else +TRACE_EVENT(preemptirqsoff_hist, + + TP_PROTO(int reason, int starthist), + + TP_ARGS(reason, starthist), + + TP_STRUCT__entry( + __field(int, reason) + __field(int, starthist) + ), + + TP_fast_assign( + __entry->reason = reason; + __entry->starthist = starthist; + ), + + TP_printk("reason=%s starthist=%s", getaction(__entry->reason), + __entry->starthist ? "start" : "stop") +); +#endif + +#ifndef CONFIG_MISSED_TIMER_OFFSETS_HIST +#define trace_hrtimer_interrupt(a, b, c, d) +#else +TRACE_EVENT(hrtimer_interrupt, + + TP_PROTO(int cpu, long long offset, struct task_struct *curr, + struct task_struct *task), + + TP_ARGS(cpu, offset, curr, task), + + TP_STRUCT__entry( + __field(int, cpu) + __field(long long, offset) + __array(char, ccomm, TASK_COMM_LEN) + __field(int, cprio) + __array(char, tcomm, TASK_COMM_LEN) + __field(int, tprio) + ), + + TP_fast_assign( + __entry->cpu = cpu; + __entry->offset = offset; + memcpy(__entry->ccomm, curr->comm, TASK_COMM_LEN); + __entry->cprio = curr->prio; + memcpy(__entry->tcomm, task != NULL ? task->comm : "", + task != NULL ? TASK_COMM_LEN : 7); + __entry->tprio = task != NULL ? task->prio : -1; + ), + + TP_printk("cpu=%d offset=%lld curr=%s[%d] thread=%s[%d]", + __entry->cpu, __entry->offset, __entry->ccomm, + __entry->cprio, __entry->tcomm, __entry->tprio) +); +#endif + +#endif /* _TRACE_HIST_H */ + +/* This part must be outside protection */ +#include diff -Nur linux-3.18.14.orig/include/trace/events/latency_hist.h linux-3.18.14-rt/include/trace/events/latency_hist.h --- linux-3.18.14.orig/include/trace/events/latency_hist.h 1969-12-31 18:00:00.000000000 -0600 +++ linux-3.18.14-rt/include/trace/events/latency_hist.h 2015-05-31 15:32:48.521635366 -0500 @@ -0,0 +1,29 @@ +#ifndef _LATENCY_HIST_H +#define _LATENCY_HIST_H + +enum hist_action { + IRQS_ON, + PREEMPT_ON, + TRACE_STOP, + IRQS_OFF, + PREEMPT_OFF, + TRACE_START, +}; + +static char *actions[] = { + "IRQS_ON", + "PREEMPT_ON", + "TRACE_STOP", + "IRQS_OFF", + "PREEMPT_OFF", + "TRACE_START", +}; + +static inline char *getaction(int action) +{ + if (action >= 0 && action <= sizeof(actions)/sizeof(actions[0])) + return actions[action]; + return "unknown"; +} + +#endif /* _LATENCY_HIST_H */ diff -Nur linux-3.18.14.orig/init/Kconfig linux-3.18.14-rt/init/Kconfig --- linux-3.18.14.orig/init/Kconfig 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/init/Kconfig 2015-05-31 15:32:48.525635366 -0500 @@ -635,7 +635,7 @@ config RCU_FAST_NO_HZ bool "Accelerate last non-dyntick-idle CPU's grace periods" - depends on NO_HZ_COMMON && SMP + depends on NO_HZ_COMMON && SMP && !PREEMPT_RT_FULL default n help This option permits CPUs to enter dynticks-idle state even if @@ -662,7 +662,7 @@ config RCU_BOOST bool "Enable RCU priority boosting" depends on RT_MUTEXES && PREEMPT_RCU - default n + default y if PREEMPT_RT_FULL help This option boosts the priority of preempted RCU readers that block the current preemptible RCU grace period for too long. @@ -1106,6 +1106,7 @@ config RT_GROUP_SCHED bool "Group scheduling for SCHED_RR/FIFO" depends on CGROUP_SCHED + depends on !PREEMPT_RT_FULL default n help This feature lets you explicitly allocate real CPU bandwidth @@ -1677,6 +1678,7 @@ config SLAB bool "SLAB" + depends on !PREEMPT_RT_FULL help The regular slab allocator that is established and known to work well in all environments. It organizes cache hot objects in @@ -1695,6 +1697,7 @@ config SLOB depends on EXPERT bool "SLOB (Simple Allocator)" + depends on !PREEMPT_RT_FULL help SLOB replaces the stock allocator with a drastically simpler allocator. SLOB is generally more space efficient but diff -Nur linux-3.18.14.orig/init/main.c linux-3.18.14-rt/init/main.c --- linux-3.18.14.orig/init/main.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/init/main.c 2015-05-31 15:32:48.545635366 -0500 @@ -533,6 +533,7 @@ setup_command_line(command_line); setup_nr_cpu_ids(); setup_per_cpu_areas(); + softirq_early_init(); smp_prepare_boot_cpu(); /* arch-specific boot-cpu hooks */ build_all_zonelists(NULL, NULL); diff -Nur linux-3.18.14.orig/init/Makefile linux-3.18.14-rt/init/Makefile --- linux-3.18.14.orig/init/Makefile 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/init/Makefile 2015-05-31 15:32:48.525635366 -0500 @@ -33,4 +33,4 @@ include/generated/compile.h: FORCE @$($(quiet)chk_compile.h) $(Q)$(CONFIG_SHELL) $(srctree)/scripts/mkcompile_h $@ \ - "$(UTS_MACHINE)" "$(CONFIG_SMP)" "$(CONFIG_PREEMPT)" "$(CC) $(KBUILD_CFLAGS)" + "$(UTS_MACHINE)" "$(CONFIG_SMP)" "$(CONFIG_PREEMPT)" "$(CONFIG_PREEMPT_RT_FULL)" "$(CC) $(KBUILD_CFLAGS)" diff -Nur linux-3.18.14.orig/ipc/mqueue.c linux-3.18.14-rt/ipc/mqueue.c --- linux-3.18.14.orig/ipc/mqueue.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/ipc/mqueue.c 2015-05-31 15:32:48.557635366 -0500 @@ -923,12 +923,17 @@ struct msg_msg *message, struct ext_wait_queue *receiver) { + /* + * Keep them in one critical section for PREEMPT_RT: + */ + preempt_disable_rt(); receiver->msg = message; list_del(&receiver->list); receiver->state = STATE_PENDING; wake_up_process(receiver->task); smp_wmb(); receiver->state = STATE_READY; + preempt_enable_rt(); } /* pipelined_receive() - if there is task waiting in sys_mq_timedsend() @@ -942,13 +947,18 @@ wake_up_interruptible(&info->wait_q); return; } - if (msg_insert(sender->msg, info)) - return; - list_del(&sender->list); - sender->state = STATE_PENDING; - wake_up_process(sender->task); - smp_wmb(); - sender->state = STATE_READY; + /* + * Keep them in one critical section for PREEMPT_RT: + */ + preempt_disable_rt(); + if (!msg_insert(sender->msg, info)) { + list_del(&sender->list); + sender->state = STATE_PENDING; + wake_up_process(sender->task); + smp_wmb(); + sender->state = STATE_READY; + } + preempt_enable_rt(); } SYSCALL_DEFINE5(mq_timedsend, mqd_t, mqdes, const char __user *, u_msg_ptr, diff -Nur linux-3.18.14.orig/ipc/msg.c linux-3.18.14-rt/ipc/msg.c --- linux-3.18.14.orig/ipc/msg.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/ipc/msg.c 2015-05-31 15:32:48.577635366 -0500 @@ -188,6 +188,12 @@ struct msg_receiver *msr, *t; list_for_each_entry_safe(msr, t, &msq->q_receivers, r_list) { + /* + * Make sure that the wakeup doesnt preempt + * this CPU prematurely. (on PREEMPT_RT) + */ + preempt_disable_rt(); + msr->r_msg = NULL; /* initialize expunge ordering */ wake_up_process(msr->r_tsk); /* @@ -198,6 +204,8 @@ */ smp_mb(); msr->r_msg = ERR_PTR(res); + + preempt_enable_rt(); } } @@ -574,6 +582,11 @@ if (testmsg(msg, msr->r_msgtype, msr->r_mode) && !security_msg_queue_msgrcv(msq, msg, msr->r_tsk, msr->r_msgtype, msr->r_mode)) { + /* + * Make sure that the wakeup doesnt preempt + * this CPU prematurely. (on PREEMPT_RT) + */ + preempt_disable_rt(); list_del(&msr->r_list); if (msr->r_maxsize < msg->m_ts) { @@ -595,12 +608,13 @@ */ smp_mb(); msr->r_msg = msg; + preempt_enable_rt(); return 1; } + preempt_enable_rt(); } } - return 0; } diff -Nur linux-3.18.14.orig/ipc/sem.c linux-3.18.14-rt/ipc/sem.c --- linux-3.18.14.orig/ipc/sem.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/ipc/sem.c 2015-05-31 15:32:48.577635366 -0500 @@ -673,6 +673,13 @@ static void wake_up_sem_queue_prepare(struct list_head *pt, struct sem_queue *q, int error) { +#ifdef CONFIG_PREEMPT_RT_BASE + struct task_struct *p = q->sleeper; + get_task_struct(p); + q->status = error; + wake_up_process(p); + put_task_struct(p); +#else if (list_empty(pt)) { /* * Hold preempt off so that we don't get preempted and have the @@ -684,6 +691,7 @@ q->pid = error; list_add_tail(&q->list, pt); +#endif } /** @@ -697,6 +705,7 @@ */ static void wake_up_sem_queue_do(struct list_head *pt) { +#ifndef CONFIG_PREEMPT_RT_BASE struct sem_queue *q, *t; int did_something; @@ -709,6 +718,7 @@ } if (did_something) preempt_enable(); +#endif } static void unlink_queue(struct sem_array *sma, struct sem_queue *q) diff -Nur linux-3.18.14.orig/kernel/cgroup.c linux-3.18.14-rt/kernel/cgroup.c --- linux-3.18.14.orig/kernel/cgroup.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/cgroup.c 2015-05-31 15:32:48.597635365 -0500 @@ -4355,10 +4355,10 @@ queue_work(cgroup_destroy_wq, &css->destroy_work); } -static void css_release_work_fn(struct work_struct *work) +static void css_release_work_fn(struct swork_event *sev) { struct cgroup_subsys_state *css = - container_of(work, struct cgroup_subsys_state, destroy_work); + container_of(sev, struct cgroup_subsys_state, destroy_swork); struct cgroup_subsys *ss = css->ss; struct cgroup *cgrp = css->cgroup; @@ -4395,8 +4395,8 @@ struct cgroup_subsys_state *css = container_of(ref, struct cgroup_subsys_state, refcnt); - INIT_WORK(&css->destroy_work, css_release_work_fn); - queue_work(cgroup_destroy_wq, &css->destroy_work); + INIT_SWORK(&css->destroy_swork, css_release_work_fn); + swork_queue(&css->destroy_swork); } static void init_and_link_css(struct cgroup_subsys_state *css, @@ -4997,6 +4997,7 @@ */ cgroup_destroy_wq = alloc_workqueue("cgroup_destroy", 0, 1); BUG_ON(!cgroup_destroy_wq); + BUG_ON(swork_get()); /* * Used to destroy pidlists and separate to serve as flush domain. diff -Nur linux-3.18.14.orig/kernel/cpu.c linux-3.18.14-rt/kernel/cpu.c --- linux-3.18.14.orig/kernel/cpu.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/cpu.c 2015-05-31 15:32:48.601635365 -0500 @@ -86,6 +86,290 @@ #define cpuhp_lock_acquire() lock_map_acquire(&cpu_hotplug.dep_map) #define cpuhp_lock_release() lock_map_release(&cpu_hotplug.dep_map) +/** + * hotplug_pcp - per cpu hotplug descriptor + * @unplug: set when pin_current_cpu() needs to sync tasks + * @sync_tsk: the task that waits for tasks to finish pinned sections + * @refcount: counter of tasks in pinned sections + * @grab_lock: set when the tasks entering pinned sections should wait + * @synced: notifier for @sync_tsk to tell cpu_down it's finished + * @mutex: the mutex to make tasks wait (used when @grab_lock is true) + * @mutex_init: zero if the mutex hasn't been initialized yet. + * + * Although @unplug and @sync_tsk may point to the same task, the @unplug + * is used as a flag and still exists after @sync_tsk has exited and + * @sync_tsk set to NULL. + */ +struct hotplug_pcp { + struct task_struct *unplug; + struct task_struct *sync_tsk; + int refcount; + int grab_lock; + struct completion synced; + struct completion unplug_wait; +#ifdef CONFIG_PREEMPT_RT_FULL + /* + * Note, on PREEMPT_RT, the hotplug lock must save the state of + * the task, otherwise the mutex will cause the task to fail + * to sleep when required. (Because it's called from migrate_disable()) + * + * The spinlock_t on PREEMPT_RT is a mutex that saves the task's + * state. + */ + spinlock_t lock; +#else + struct mutex mutex; +#endif + int mutex_init; +}; + +#ifdef CONFIG_PREEMPT_RT_FULL +# define hotplug_lock(hp) rt_spin_lock(&(hp)->lock) +# define hotplug_unlock(hp) rt_spin_unlock(&(hp)->lock) +#else +# define hotplug_lock(hp) mutex_lock(&(hp)->mutex) +# define hotplug_unlock(hp) mutex_unlock(&(hp)->mutex) +#endif + +static DEFINE_PER_CPU(struct hotplug_pcp, hotplug_pcp); + +/** + * pin_current_cpu - Prevent the current cpu from being unplugged + * + * Lightweight version of get_online_cpus() to prevent cpu from being + * unplugged when code runs in a migration disabled region. + * + * Must be called with preemption disabled (preempt_count = 1)! + */ +void pin_current_cpu(void) +{ + struct hotplug_pcp *hp; + int force = 0; + +retry: + hp = &__get_cpu_var(hotplug_pcp); + + if (!hp->unplug || hp->refcount || force || preempt_count() > 1 || + hp->unplug == current) { + hp->refcount++; + return; + } + if (hp->grab_lock) { + preempt_enable(); + hotplug_lock(hp); + hotplug_unlock(hp); + } else { + preempt_enable(); + /* + * Try to push this task off of this CPU. + */ + if (!migrate_me()) { + preempt_disable(); + hp = &__get_cpu_var(hotplug_pcp); + if (!hp->grab_lock) { + /* + * Just let it continue it's already pinned + * or about to sleep. + */ + force = 1; + goto retry; + } + preempt_enable(); + } + } + preempt_disable(); + goto retry; +} + +/** + * unpin_current_cpu - Allow unplug of current cpu + * + * Must be called with preemption or interrupts disabled! + */ +void unpin_current_cpu(void) +{ + struct hotplug_pcp *hp = &__get_cpu_var(hotplug_pcp); + + WARN_ON(hp->refcount <= 0); + + /* This is safe. sync_unplug_thread is pinned to this cpu */ + if (!--hp->refcount && hp->unplug && hp->unplug != current) + wake_up_process(hp->unplug); +} + +static void wait_for_pinned_cpus(struct hotplug_pcp *hp) +{ + set_current_state(TASK_UNINTERRUPTIBLE); + while (hp->refcount) { + schedule_preempt_disabled(); + set_current_state(TASK_UNINTERRUPTIBLE); + } +} + +static int sync_unplug_thread(void *data) +{ + struct hotplug_pcp *hp = data; + + wait_for_completion(&hp->unplug_wait); + preempt_disable(); + hp->unplug = current; + wait_for_pinned_cpus(hp); + + /* + * This thread will synchronize the cpu_down() with threads + * that have pinned the CPU. When the pinned CPU count reaches + * zero, we inform the cpu_down code to continue to the next step. + */ + set_current_state(TASK_UNINTERRUPTIBLE); + preempt_enable(); + complete(&hp->synced); + + /* + * If all succeeds, the next step will need tasks to wait till + * the CPU is offline before continuing. To do this, the grab_lock + * is set and tasks going into pin_current_cpu() will block on the + * mutex. But we still need to wait for those that are already in + * pinned CPU sections. If the cpu_down() failed, the kthread_should_stop() + * will kick this thread out. + */ + while (!hp->grab_lock && !kthread_should_stop()) { + schedule(); + set_current_state(TASK_UNINTERRUPTIBLE); + } + + /* Make sure grab_lock is seen before we see a stale completion */ + smp_mb(); + + /* + * Now just before cpu_down() enters stop machine, we need to make + * sure all tasks that are in pinned CPU sections are out, and new + * tasks will now grab the lock, keeping them from entering pinned + * CPU sections. + */ + if (!kthread_should_stop()) { + preempt_disable(); + wait_for_pinned_cpus(hp); + preempt_enable(); + complete(&hp->synced); + } + + set_current_state(TASK_UNINTERRUPTIBLE); + while (!kthread_should_stop()) { + schedule(); + set_current_state(TASK_UNINTERRUPTIBLE); + } + set_current_state(TASK_RUNNING); + + /* + * Force this thread off this CPU as it's going down and + * we don't want any more work on this CPU. + */ + current->flags &= ~PF_NO_SETAFFINITY; + set_cpus_allowed_ptr(current, cpu_present_mask); + migrate_me(); + return 0; +} + +static void __cpu_unplug_sync(struct hotplug_pcp *hp) +{ + wake_up_process(hp->sync_tsk); + wait_for_completion(&hp->synced); +} + +static void __cpu_unplug_wait(unsigned int cpu) +{ + struct hotplug_pcp *hp = &per_cpu(hotplug_pcp, cpu); + + complete(&hp->unplug_wait); + wait_for_completion(&hp->synced); +} + +/* + * Start the sync_unplug_thread on the target cpu and wait for it to + * complete. + */ +static int cpu_unplug_begin(unsigned int cpu) +{ + struct hotplug_pcp *hp = &per_cpu(hotplug_pcp, cpu); + int err; + + /* Protected by cpu_hotplug.lock */ + if (!hp->mutex_init) { +#ifdef CONFIG_PREEMPT_RT_FULL + spin_lock_init(&hp->lock); +#else + mutex_init(&hp->mutex); +#endif + hp->mutex_init = 1; + } + + /* Inform the scheduler to migrate tasks off this CPU */ + tell_sched_cpu_down_begin(cpu); + + init_completion(&hp->synced); + init_completion(&hp->unplug_wait); + + hp->sync_tsk = kthread_create(sync_unplug_thread, hp, "sync_unplug/%d", cpu); + if (IS_ERR(hp->sync_tsk)) { + err = PTR_ERR(hp->sync_tsk); + hp->sync_tsk = NULL; + return err; + } + kthread_bind(hp->sync_tsk, cpu); + + /* + * Wait for tasks to get out of the pinned sections, + * it's still OK if new tasks enter. Some CPU notifiers will + * wait for tasks that are going to enter these sections and + * we must not have them block. + */ + wake_up_process(hp->sync_tsk); + return 0; +} + +static void cpu_unplug_sync(unsigned int cpu) +{ + struct hotplug_pcp *hp = &per_cpu(hotplug_pcp, cpu); + + init_completion(&hp->synced); + /* The completion needs to be initialzied before setting grab_lock */ + smp_wmb(); + + /* Grab the mutex before setting grab_lock */ + hotplug_lock(hp); + hp->grab_lock = 1; + + /* + * The CPU notifiers have been completed. + * Wait for tasks to get out of pinned CPU sections and have new + * tasks block until the CPU is completely down. + */ + __cpu_unplug_sync(hp); + + /* All done with the sync thread */ + kthread_stop(hp->sync_tsk); + hp->sync_tsk = NULL; +} + +static void cpu_unplug_done(unsigned int cpu) +{ + struct hotplug_pcp *hp = &per_cpu(hotplug_pcp, cpu); + + hp->unplug = NULL; + /* Let all tasks know cpu unplug is finished before cleaning up */ + smp_wmb(); + + if (hp->sync_tsk) + kthread_stop(hp->sync_tsk); + + if (hp->grab_lock) { + hotplug_unlock(hp); + /* protected by cpu_hotplug.lock */ + hp->grab_lock = 0; + } + tell_sched_cpu_down_done(cpu); +} + void get_online_cpus(void) { might_sleep(); @@ -102,6 +386,7 @@ { if (cpu_hotplug.active_writer == current) return true; + if (!mutex_trylock(&cpu_hotplug.lock)) return false; cpuhp_lock_acquire_tryread(); @@ -349,13 +634,15 @@ /* Requires cpu_add_remove_lock to be held */ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen) { - int err, nr_calls = 0; + int mycpu, err, nr_calls = 0; void *hcpu = (void *)(long)cpu; unsigned long mod = tasks_frozen ? CPU_TASKS_FROZEN : 0; struct take_cpu_down_param tcd_param = { .mod = mod, .hcpu = hcpu, }; + cpumask_var_t cpumask; + cpumask_var_t cpumask_org; if (num_online_cpus() == 1) return -EBUSY; @@ -363,7 +650,34 @@ if (!cpu_online(cpu)) return -EINVAL; + /* Move the downtaker off the unplug cpu */ + if (!alloc_cpumask_var(&cpumask, GFP_KERNEL)) + return -ENOMEM; + if (!alloc_cpumask_var(&cpumask_org, GFP_KERNEL)) { + free_cpumask_var(cpumask); + return -ENOMEM; + } + + cpumask_copy(cpumask_org, tsk_cpus_allowed(current)); + cpumask_andnot(cpumask, cpu_online_mask, cpumask_of(cpu)); + set_cpus_allowed_ptr(current, cpumask); + free_cpumask_var(cpumask); + migrate_disable(); + mycpu = smp_processor_id(); + if (mycpu == cpu) { + printk(KERN_ERR "Yuck! Still on unplug CPU\n!"); + migrate_enable(); + err = -EBUSY; + goto restore_cpus; + } + migrate_enable(); + cpu_hotplug_begin(); + err = cpu_unplug_begin(cpu); + if (err) { + printk("cpu_unplug_begin(%d) failed\n", cpu); + goto out_cancel; + } err = __cpu_notify(CPU_DOWN_PREPARE | mod, hcpu, -1, &nr_calls); if (err) { @@ -389,8 +703,12 @@ #endif synchronize_rcu(); + __cpu_unplug_wait(cpu); smpboot_park_threads(cpu); + /* Notifiers are done. Don't let any more tasks pin this CPU. */ + cpu_unplug_sync(cpu); + /* * So now all preempt/rcu users must observe !cpu_active(). */ @@ -423,9 +741,14 @@ check_for_tasks(cpu); out_release: + cpu_unplug_done(cpu); +out_cancel: cpu_hotplug_done(); if (!err) cpu_notify_nofail(CPU_POST_DEAD | mod, hcpu); +restore_cpus: + set_cpus_allowed_ptr(current, cpumask_org); + free_cpumask_var(cpumask_org); return err; } diff -Nur linux-3.18.14.orig/kernel/debug/kdb/kdb_io.c linux-3.18.14-rt/kernel/debug/kdb/kdb_io.c --- linux-3.18.14.orig/kernel/debug/kdb/kdb_io.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/debug/kdb/kdb_io.c 2015-05-31 15:32:48.605635366 -0500 @@ -554,7 +554,6 @@ int linecount; int colcount; int logging, saved_loglevel = 0; - int saved_trap_printk; int got_printf_lock = 0; int retlen = 0; int fnd, len; @@ -565,8 +564,6 @@ unsigned long uninitialized_var(flags); preempt_disable(); - saved_trap_printk = kdb_trap_printk; - kdb_trap_printk = 0; /* Serialize kdb_printf if multiple cpus try to write at once. * But if any cpu goes recursive in kdb, just print the output, @@ -833,7 +830,6 @@ } else { __release(kdb_printf_lock); } - kdb_trap_printk = saved_trap_printk; preempt_enable(); return retlen; } @@ -843,9 +839,11 @@ va_list ap; int r; + kdb_trap_printk++; va_start(ap, fmt); r = vkdb_printf(fmt, ap); va_end(ap); + kdb_trap_printk--; return r; } diff -Nur linux-3.18.14.orig/kernel/events/core.c linux-3.18.14-rt/kernel/events/core.c --- linux-3.18.14.orig/kernel/events/core.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/events/core.c 2015-05-31 15:32:48.637635365 -0500 @@ -6346,6 +6346,7 @@ hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); hwc->hrtimer.function = perf_swevent_hrtimer; + hwc->hrtimer.irqsafe = 1; /* * Since hrtimers have a fixed rate, we can do a static freq->period diff -Nur linux-3.18.14.orig/kernel/exit.c linux-3.18.14-rt/kernel/exit.c --- linux-3.18.14.orig/kernel/exit.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/exit.c 2015-05-31 15:32:48.649635365 -0500 @@ -147,7 +147,7 @@ * Do this under ->siglock, we can race with another thread * doing sigqueue_free() if we have SIGQUEUE_PREALLOC signals. */ - flush_sigqueue(&tsk->pending); + flush_task_sigqueue(tsk); tsk->sighand = NULL; spin_unlock(&sighand->siglock); diff -Nur linux-3.18.14.orig/kernel/fork.c linux-3.18.14-rt/kernel/fork.c --- linux-3.18.14.orig/kernel/fork.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/fork.c 2015-05-31 15:32:48.657635365 -0500 @@ -97,7 +97,7 @@ DEFINE_PER_CPU(unsigned long, process_counts) = 0; -__cacheline_aligned DEFINE_RWLOCK(tasklist_lock); /* outer */ +DEFINE_RWLOCK(tasklist_lock); /* outer */ #ifdef CONFIG_PROVE_RCU int lockdep_tasklist_lock_is_held(void) @@ -233,7 +233,9 @@ if (atomic_dec_and_test(&sig->sigcnt)) free_signal_struct(sig); } - +#ifdef CONFIG_PREEMPT_RT_BASE +static +#endif void __put_task_struct(struct task_struct *tsk) { WARN_ON(!tsk->exit_state); @@ -249,7 +251,18 @@ if (!profile_handoff_task(tsk)) free_task(tsk); } +#ifndef CONFIG_PREEMPT_RT_BASE EXPORT_SYMBOL_GPL(__put_task_struct); +#else +void __put_task_struct_cb(struct rcu_head *rhp) +{ + struct task_struct *tsk = container_of(rhp, struct task_struct, put_rcu); + + __put_task_struct(tsk); + +} +EXPORT_SYMBOL_GPL(__put_task_struct_cb); +#endif void __init __weak arch_task_cache_init(void) { } @@ -643,6 +656,19 @@ } EXPORT_SYMBOL_GPL(__mmdrop); +#ifdef CONFIG_PREEMPT_RT_BASE +/* + * RCU callback for delayed mm drop. Not strictly rcu, but we don't + * want another facility to make this work. + */ +void __mmdrop_delayed(struct rcu_head *rhp) +{ + struct mm_struct *mm = container_of(rhp, struct mm_struct, delayed_drop); + + __mmdrop(mm); +} +#endif + /* * Decrement the use count and release all resources for an mm. */ @@ -1157,6 +1183,9 @@ */ static void posix_cpu_timers_init(struct task_struct *tsk) { +#ifdef CONFIG_PREEMPT_RT_BASE + tsk->posix_timer_list = NULL; +#endif tsk->cputime_expires.prof_exp = 0; tsk->cputime_expires.virt_exp = 0; tsk->cputime_expires.sched_exp = 0; @@ -1284,6 +1313,7 @@ spin_lock_init(&p->alloc_lock); init_sigpending(&p->pending); + p->sigqueue_cache = NULL; p->utime = p->stime = p->gtime = 0; p->utimescaled = p->stimescaled = 0; @@ -1291,7 +1321,8 @@ p->prev_cputime.utime = p->prev_cputime.stime = 0; #endif #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN - seqlock_init(&p->vtime_seqlock); + raw_spin_lock_init(&p->vtime_lock); + seqcount_init(&p->vtime_seq); p->vtime_snap = 0; p->vtime_snap_whence = VTIME_SLEEPING; #endif @@ -1342,6 +1373,9 @@ p->hardirq_context = 0; p->softirq_context = 0; #endif +#ifdef CONFIG_PREEMPT_RT_FULL + p->pagefault_disabled = 0; +#endif #ifdef CONFIG_LOCKDEP p->lockdep_depth = 0; /* no locks held yet */ p->curr_chain_key = 0; diff -Nur linux-3.18.14.orig/kernel/futex.c linux-3.18.14-rt/kernel/futex.c --- linux-3.18.14.orig/kernel/futex.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/futex.c 2015-05-31 15:32:48.665635365 -0500 @@ -738,7 +738,9 @@ * task still owns the PI-state: */ if (head->next != next) { + raw_spin_unlock_irq(&curr->pi_lock); spin_unlock(&hb->lock); + raw_spin_lock_irq(&curr->pi_lock); continue; } @@ -1705,6 +1707,16 @@ requeue_pi_wake_futex(this, &key2, hb2); drop_count++; continue; + } else if (ret == -EAGAIN) { + /* + * Waiter was woken by timeout or + * signal and has set pi_blocked_on to + * PI_WAKEUP_INPROGRESS before we + * tried to enqueue it on the rtmutex. + */ + this->pi_state = NULL; + free_pi_state(pi_state); + continue; } else if (ret) { /* -EDEADLK */ this->pi_state = NULL; @@ -2549,7 +2561,7 @@ struct hrtimer_sleeper timeout, *to = NULL; struct rt_mutex_waiter rt_waiter; struct rt_mutex *pi_mutex = NULL; - struct futex_hash_bucket *hb; + struct futex_hash_bucket *hb, *hb2; union futex_key key2 = FUTEX_KEY_INIT; struct futex_q q = futex_q_init; int res, ret; @@ -2574,10 +2586,7 @@ * The waiter is allocated on our stack, manipulated by the requeue * code while we sleep on uaddr. */ - debug_rt_mutex_init_waiter(&rt_waiter); - RB_CLEAR_NODE(&rt_waiter.pi_tree_entry); - RB_CLEAR_NODE(&rt_waiter.tree_entry); - rt_waiter.task = NULL; + rt_mutex_init_waiter(&rt_waiter, false); ret = get_futex_key(uaddr2, flags & FLAGS_SHARED, &key2, VERIFY_WRITE); if (unlikely(ret != 0)) @@ -2608,20 +2617,55 @@ /* Queue the futex_q, drop the hb lock, wait for wakeup. */ futex_wait_queue_me(hb, &q, to); - spin_lock(&hb->lock); - ret = handle_early_requeue_pi_wakeup(hb, &q, &key2, to); - spin_unlock(&hb->lock); - if (ret) - goto out_put_keys; + /* + * On RT we must avoid races with requeue and trying to block + * on two mutexes (hb->lock and uaddr2's rtmutex) by + * serializing access to pi_blocked_on with pi_lock. + */ + raw_spin_lock_irq(¤t->pi_lock); + if (current->pi_blocked_on) { + /* + * We have been requeued or are in the process of + * being requeued. + */ + raw_spin_unlock_irq(¤t->pi_lock); + } else { + /* + * Setting pi_blocked_on to PI_WAKEUP_INPROGRESS + * prevents a concurrent requeue from moving us to the + * uaddr2 rtmutex. After that we can safely acquire + * (and possibly block on) hb->lock. + */ + current->pi_blocked_on = PI_WAKEUP_INPROGRESS; + raw_spin_unlock_irq(¤t->pi_lock); + + spin_lock(&hb->lock); + + /* + * Clean up pi_blocked_on. We might leak it otherwise + * when we succeeded with the hb->lock in the fast + * path. + */ + raw_spin_lock_irq(¤t->pi_lock); + current->pi_blocked_on = NULL; + raw_spin_unlock_irq(¤t->pi_lock); + + ret = handle_early_requeue_pi_wakeup(hb, &q, &key2, to); + spin_unlock(&hb->lock); + if (ret) + goto out_put_keys; + } /* - * In order for us to be here, we know our q.key == key2, and since - * we took the hb->lock above, we also know that futex_requeue() has - * completed and we no longer have to concern ourselves with a wakeup - * race with the atomic proxy lock acquisition by the requeue code. The - * futex_requeue dropped our key1 reference and incremented our key2 - * reference count. + * In order to be here, we have either been requeued, are in + * the process of being requeued, or requeue successfully + * acquired uaddr2 on our behalf. If pi_blocked_on was + * non-null above, we may be racing with a requeue. Do not + * rely on q->lock_ptr to be hb2->lock until after blocking on + * hb->lock or hb2->lock. The futex_requeue dropped our key1 + * reference and incremented our key2 reference count. */ + hb2 = hash_futex(&key2); /* Check if the requeue code acquired the second futex for us. */ if (!q.rt_waiter) { @@ -2630,9 +2674,10 @@ * did a lock-steal - fix up the PI-state in that case. */ if (q.pi_state && (q.pi_state->owner != current)) { - spin_lock(q.lock_ptr); + spin_lock(&hb2->lock); + BUG_ON(&hb2->lock != q.lock_ptr); ret = fixup_pi_state_owner(uaddr2, &q, current); - spin_unlock(q.lock_ptr); + spin_unlock(&hb2->lock); } } else { /* @@ -2645,7 +2690,8 @@ ret = rt_mutex_finish_proxy_lock(pi_mutex, to, &rt_waiter); debug_rt_mutex_free_waiter(&rt_waiter); - spin_lock(q.lock_ptr); + spin_lock(&hb2->lock); + BUG_ON(&hb2->lock != q.lock_ptr); /* * Fixup the pi_state owner and possibly acquire the lock if we * haven't already. diff -Nur linux-3.18.14.orig/kernel/irq/handle.c linux-3.18.14-rt/kernel/irq/handle.c --- linux-3.18.14.orig/kernel/irq/handle.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/irq/handle.c 2015-05-31 15:32:48.677635365 -0500 @@ -133,6 +133,8 @@ irqreturn_t handle_irq_event_percpu(struct irq_desc *desc, struct irqaction *action) { + struct pt_regs *regs = get_irq_regs(); + u64 ip = regs ? instruction_pointer(regs) : 0; irqreturn_t retval = IRQ_NONE; unsigned int flags = 0, irq = desc->irq_data.irq; @@ -173,7 +175,11 @@ action = action->next; } while (action); - add_interrupt_randomness(irq, flags); +#ifndef CONFIG_PREEMPT_RT_FULL + add_interrupt_randomness(irq, flags, ip); +#else + desc->random_ip = ip; +#endif if (!noirqdebug) note_interrupt(irq, desc, retval); diff -Nur linux-3.18.14.orig/kernel/irq/manage.c linux-3.18.14-rt/kernel/irq/manage.c --- linux-3.18.14.orig/kernel/irq/manage.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/irq/manage.c 2015-05-31 15:32:48.697635365 -0500 @@ -22,6 +22,7 @@ #include "internals.h" #ifdef CONFIG_IRQ_FORCED_THREADING +# ifndef CONFIG_PREEMPT_RT_BASE __read_mostly bool force_irqthreads; static int __init setup_forced_irqthreads(char *arg) @@ -30,6 +31,7 @@ return 0; } early_param("threadirqs", setup_forced_irqthreads); +# endif #endif static void __synchronize_hardirq(struct irq_desc *desc) @@ -173,6 +175,62 @@ irq_get_pending(struct cpumask *mask, struct irq_desc *desc) { } #endif +#ifdef CONFIG_PREEMPT_RT_FULL +static void _irq_affinity_notify(struct irq_affinity_notify *notify); +static struct task_struct *set_affinity_helper; +static LIST_HEAD(affinity_list); +static DEFINE_RAW_SPINLOCK(affinity_list_lock); + +static int set_affinity_thread(void *unused) +{ + while (1) { + struct irq_affinity_notify *notify; + int empty; + + set_current_state(TASK_INTERRUPTIBLE); + + raw_spin_lock_irq(&affinity_list_lock); + empty = list_empty(&affinity_list); + raw_spin_unlock_irq(&affinity_list_lock); + + if (empty) + schedule(); + if (kthread_should_stop()) + break; + set_current_state(TASK_RUNNING); +try_next: + notify = NULL; + + raw_spin_lock_irq(&affinity_list_lock); + if (!list_empty(&affinity_list)) { + notify = list_first_entry(&affinity_list, + struct irq_affinity_notify, list); + list_del_init(¬ify->list); + } + raw_spin_unlock_irq(&affinity_list_lock); + + if (!notify) + continue; + _irq_affinity_notify(notify); + goto try_next; + } + return 0; +} + +static void init_helper_thread(void) +{ + if (set_affinity_helper) + return; + set_affinity_helper = kthread_run(set_affinity_thread, NULL, + "affinity-cb"); + WARN_ON(IS_ERR(set_affinity_helper)); +} +#else + +static inline void init_helper_thread(void) { } + +#endif + int irq_do_set_affinity(struct irq_data *data, const struct cpumask *mask, bool force) { @@ -211,7 +269,17 @@ if (desc->affinity_notify) { kref_get(&desc->affinity_notify->kref); + +#ifdef CONFIG_PREEMPT_RT_FULL + raw_spin_lock(&affinity_list_lock); + if (list_empty(&desc->affinity_notify->list)) + list_add_tail(&affinity_list, + &desc->affinity_notify->list); + raw_spin_unlock(&affinity_list_lock); + wake_up_process(set_affinity_helper); +#else schedule_work(&desc->affinity_notify->work); +#endif } irqd_set(data, IRQD_AFFINITY_SET); @@ -246,10 +314,8 @@ } EXPORT_SYMBOL_GPL(irq_set_affinity_hint); -static void irq_affinity_notify(struct work_struct *work) +static void _irq_affinity_notify(struct irq_affinity_notify *notify) { - struct irq_affinity_notify *notify = - container_of(work, struct irq_affinity_notify, work); struct irq_desc *desc = irq_to_desc(notify->irq); cpumask_var_t cpumask; unsigned long flags; @@ -271,6 +337,13 @@ kref_put(¬ify->kref, notify->release); } +static void irq_affinity_notify(struct work_struct *work) +{ + struct irq_affinity_notify *notify = + container_of(work, struct irq_affinity_notify, work); + _irq_affinity_notify(notify); +} + /** * irq_set_affinity_notifier - control notification of IRQ affinity changes * @irq: Interrupt for which to enable/disable notification @@ -300,6 +373,8 @@ notify->irq = irq; kref_init(¬ify->kref); INIT_WORK(¬ify->work, irq_affinity_notify); + INIT_LIST_HEAD(¬ify->list); + init_helper_thread(); } raw_spin_lock_irqsave(&desc->lock, flags); @@ -788,7 +863,15 @@ local_bh_disable(); ret = action->thread_fn(action->irq, action->dev_id); irq_finalize_oneshot(desc, action); - local_bh_enable(); + /* + * Interrupts which have real time requirements can be set up + * to avoid softirq processing in the thread handler. This is + * safe as these interrupts do not raise soft interrupts. + */ + if (irq_settings_no_softirq_call(desc)) + _local_bh_enable(); + else + local_bh_enable(); return ret; } @@ -871,6 +954,12 @@ if (action_ret == IRQ_HANDLED) atomic_inc(&desc->threads_handled); +#ifdef CONFIG_PREEMPT_RT_FULL + migrate_disable(); + add_interrupt_randomness(action->irq, 0, + desc->random_ip ^ (unsigned long) action); + migrate_enable(); +#endif wake_threads_waitq(desc); } @@ -1184,6 +1273,9 @@ irqd_set(&desc->irq_data, IRQD_NO_BALANCING); } + if (new->flags & IRQF_NO_SOFTIRQ_CALL) + irq_settings_set_no_softirq_call(desc); + /* Set default affinity mask once everything is setup */ setup_affinity(irq, desc, mask); diff -Nur linux-3.18.14.orig/kernel/irq/settings.h linux-3.18.14-rt/kernel/irq/settings.h --- linux-3.18.14.orig/kernel/irq/settings.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/irq/settings.h 2015-05-31 15:32:48.697635365 -0500 @@ -15,6 +15,7 @@ _IRQ_NESTED_THREAD = IRQ_NESTED_THREAD, _IRQ_PER_CPU_DEVID = IRQ_PER_CPU_DEVID, _IRQ_IS_POLLED = IRQ_IS_POLLED, + _IRQ_NO_SOFTIRQ_CALL = IRQ_NO_SOFTIRQ_CALL, _IRQF_MODIFY_MASK = IRQF_MODIFY_MASK, }; @@ -28,6 +29,7 @@ #define IRQ_NESTED_THREAD GOT_YOU_MORON #define IRQ_PER_CPU_DEVID GOT_YOU_MORON #define IRQ_IS_POLLED GOT_YOU_MORON +#define IRQ_NO_SOFTIRQ_CALL GOT_YOU_MORON #undef IRQF_MODIFY_MASK #define IRQF_MODIFY_MASK GOT_YOU_MORON @@ -38,6 +40,16 @@ desc->status_use_accessors |= (set & _IRQF_MODIFY_MASK); } +static inline bool irq_settings_no_softirq_call(struct irq_desc *desc) +{ + return desc->status_use_accessors & _IRQ_NO_SOFTIRQ_CALL; +} + +static inline void irq_settings_set_no_softirq_call(struct irq_desc *desc) +{ + desc->status_use_accessors |= _IRQ_NO_SOFTIRQ_CALL; +} + static inline bool irq_settings_is_per_cpu(struct irq_desc *desc) { return desc->status_use_accessors & _IRQ_PER_CPU; diff -Nur linux-3.18.14.orig/kernel/irq/spurious.c linux-3.18.14-rt/kernel/irq/spurious.c --- linux-3.18.14.orig/kernel/irq/spurious.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/irq/spurious.c 2015-05-31 15:32:48.709635364 -0500 @@ -444,6 +444,10 @@ static int __init irqfixup_setup(char *str) { +#ifdef CONFIG_PREEMPT_RT_BASE + pr_warn("irqfixup boot option not supported w/ CONFIG_PREEMPT_RT_BASE\n"); + return 1; +#endif irqfixup = 1; printk(KERN_WARNING "Misrouted IRQ fixup support enabled.\n"); printk(KERN_WARNING "This may impact system performance.\n"); @@ -456,6 +460,10 @@ static int __init irqpoll_setup(char *str) { +#ifdef CONFIG_PREEMPT_RT_BASE + pr_warn("irqpoll boot option not supported w/ CONFIG_PREEMPT_RT_BASE\n"); + return 1; +#endif irqfixup = 2; printk(KERN_WARNING "Misrouted IRQ fixup and polling support " "enabled\n"); diff -Nur linux-3.18.14.orig/kernel/irq_work.c linux-3.18.14-rt/kernel/irq_work.c --- linux-3.18.14.orig/kernel/irq_work.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/irq_work.c 2015-05-31 15:32:48.713635365 -0500 @@ -17,6 +17,7 @@ #include #include #include +#include #include @@ -65,6 +66,8 @@ */ bool irq_work_queue_on(struct irq_work *work, int cpu) { + struct llist_head *list; + /* All work should have been flushed before going offline */ WARN_ON_ONCE(cpu_is_offline(cpu)); @@ -75,7 +78,12 @@ if (!irq_work_claim(work)) return false; - if (llist_add(&work->llnode, &per_cpu(raised_list, cpu))) + if (IS_ENABLED(CONFIG_PREEMPT_RT_FULL) && !(work->flags & IRQ_WORK_HARD_IRQ)) + list = &per_cpu(lazy_list, cpu); + else + list = &per_cpu(raised_list, cpu); + + if (llist_add(&work->llnode, list)) arch_send_call_function_single_ipi(cpu); return true; @@ -86,6 +94,9 @@ /* Enqueue the irq work @work on the current CPU */ bool irq_work_queue(struct irq_work *work) { + struct llist_head *list; + bool lazy_work, realtime = IS_ENABLED(CONFIG_PREEMPT_RT_FULL); + /* Only queue if not already pending */ if (!irq_work_claim(work)) return false; @@ -93,13 +104,15 @@ /* Queue the entry and raise the IPI if needed. */ preempt_disable(); - /* If the work is "lazy", handle it from next tick if any */ - if (work->flags & IRQ_WORK_LAZY) { - if (llist_add(&work->llnode, this_cpu_ptr(&lazy_list)) && - tick_nohz_tick_stopped()) - arch_irq_work_raise(); - } else { - if (llist_add(&work->llnode, this_cpu_ptr(&raised_list))) + lazy_work = work->flags & IRQ_WORK_LAZY; + + if (lazy_work || (realtime && !(work->flags & IRQ_WORK_HARD_IRQ))) + list = this_cpu_ptr(&lazy_list); + else + list = this_cpu_ptr(&raised_list); + + if (llist_add(&work->llnode, list)) { + if (!lazy_work || tick_nohz_tick_stopped()) arch_irq_work_raise(); } @@ -116,9 +129,8 @@ raised = this_cpu_ptr(&raised_list); lazy = this_cpu_ptr(&lazy_list); - if (llist_empty(raised) || arch_irq_work_has_interrupt()) - if (llist_empty(lazy)) - return false; + if (llist_empty(raised) && llist_empty(lazy)) + return false; /* All work should have been flushed before going offline */ WARN_ON_ONCE(cpu_is_offline(smp_processor_id())); @@ -132,7 +144,7 @@ struct irq_work *work; struct llist_node *llnode; - BUG_ON(!irqs_disabled()); + BUG_ON(!IS_ENABLED(CONFIG_PREEMPT_RT_FULL) && !irqs_disabled()); if (llist_empty(list)) return; @@ -169,17 +181,26 @@ void irq_work_run(void) { irq_work_run_list(this_cpu_ptr(&raised_list)); - irq_work_run_list(this_cpu_ptr(&lazy_list)); + if (IS_ENABLED(CONFIG_PREEMPT_RT_FULL)) { + /* + * NOTE: we raise softirq via IPI for safety, + * and execute in irq_work_tick() to move the + * overhead from hard to soft irq context. + */ + if (!llist_empty(this_cpu_ptr(&lazy_list))) + raise_softirq(TIMER_SOFTIRQ); + } else + irq_work_run_list(this_cpu_ptr(&lazy_list)); } EXPORT_SYMBOL_GPL(irq_work_run); void irq_work_tick(void) { - struct llist_head *raised = &__get_cpu_var(raised_list); + struct llist_head *raised = this_cpu_ptr(&raised_list); if (!llist_empty(raised) && !arch_irq_work_has_interrupt()) irq_work_run_list(raised); - irq_work_run_list(&__get_cpu_var(lazy_list)); + irq_work_run_list(this_cpu_ptr(&lazy_list)); } /* diff -Nur linux-3.18.14.orig/kernel/Kconfig.locks linux-3.18.14-rt/kernel/Kconfig.locks --- linux-3.18.14.orig/kernel/Kconfig.locks 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/Kconfig.locks 2015-05-31 15:32:48.585635365 -0500 @@ -225,11 +225,11 @@ config MUTEX_SPIN_ON_OWNER def_bool y - depends on SMP && !DEBUG_MUTEXES && ARCH_SUPPORTS_ATOMIC_RMW + depends on SMP && !DEBUG_MUTEXES && ARCH_SUPPORTS_ATOMIC_RMW && !PREEMPT_RT_FULL config RWSEM_SPIN_ON_OWNER def_bool y - depends on SMP && RWSEM_XCHGADD_ALGORITHM && ARCH_SUPPORTS_ATOMIC_RMW + depends on SMP && RWSEM_XCHGADD_ALGORITHM && ARCH_SUPPORTS_ATOMIC_RMW && !PREEMPT_RT_FULL config ARCH_USE_QUEUE_RWLOCK bool diff -Nur linux-3.18.14.orig/kernel/Kconfig.preempt linux-3.18.14-rt/kernel/Kconfig.preempt --- linux-3.18.14.orig/kernel/Kconfig.preempt 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/Kconfig.preempt 2015-05-31 15:32:48.589635366 -0500 @@ -1,3 +1,16 @@ +config PREEMPT + bool + select PREEMPT_COUNT + +config PREEMPT_RT_BASE + bool + select PREEMPT + +config HAVE_PREEMPT_LAZY + bool + +config PREEMPT_LAZY + def_bool y if HAVE_PREEMPT_LAZY && PREEMPT_RT_FULL choice prompt "Preemption Model" @@ -33,9 +46,9 @@ Select this if you are building a kernel for a desktop system. -config PREEMPT +config PREEMPT__LL bool "Preemptible Kernel (Low-Latency Desktop)" - select PREEMPT_COUNT + select PREEMPT select UNINLINE_SPIN_UNLOCK if !ARCH_INLINE_SPIN_UNLOCK help This option reduces the latency of the kernel by making @@ -52,6 +65,22 @@ embedded system with latency requirements in the milliseconds range. +config PREEMPT_RTB + bool "Preemptible Kernel (Basic RT)" + select PREEMPT_RT_BASE + help + This option is basically the same as (Low-Latency Desktop) but + enables changes which are preliminary for the full preemptible + RT kernel. + +config PREEMPT_RT_FULL + bool "Fully Preemptible Kernel (RT)" + depends on IRQ_FORCED_THREADING + select PREEMPT_RT_BASE + select PREEMPT_RCU + help + All and everything + endchoice config PREEMPT_COUNT diff -Nur linux-3.18.14.orig/kernel/ksysfs.c linux-3.18.14-rt/kernel/ksysfs.c --- linux-3.18.14.orig/kernel/ksysfs.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/ksysfs.c 2015-05-31 15:32:48.733635364 -0500 @@ -136,6 +136,15 @@ #endif /* CONFIG_KEXEC */ +#if defined(CONFIG_PREEMPT_RT_FULL) +static ssize_t realtime_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + return sprintf(buf, "%d\n", 1); +} +KERNEL_ATTR_RO(realtime); +#endif + /* whether file capabilities are enabled */ static ssize_t fscaps_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) @@ -203,6 +212,9 @@ &vmcoreinfo_attr.attr, #endif &rcu_expedited_attr.attr, +#ifdef CONFIG_PREEMPT_RT_FULL + &realtime_attr.attr, +#endif NULL }; diff -Nur linux-3.18.14.orig/kernel/locking/lglock.c linux-3.18.14-rt/kernel/locking/lglock.c --- linux-3.18.14.orig/kernel/locking/lglock.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/locking/lglock.c 2015-05-31 15:32:48.749635364 -0500 @@ -4,6 +4,15 @@ #include #include +#ifndef CONFIG_PREEMPT_RT_FULL +# define lg_lock_ptr arch_spinlock_t +# define lg_do_lock(l) arch_spin_lock(l) +# define lg_do_unlock(l) arch_spin_unlock(l) +#else +# define lg_lock_ptr struct rt_mutex +# define lg_do_lock(l) __rt_spin_lock(l) +# define lg_do_unlock(l) __rt_spin_unlock(l) +#endif /* * Note there is no uninit, so lglocks cannot be defined in * modules (but it's fine to use them from there) @@ -12,51 +21,60 @@ void lg_lock_init(struct lglock *lg, char *name) { +#ifdef CONFIG_PREEMPT_RT_FULL + int i; + + for_each_possible_cpu(i) { + struct rt_mutex *lock = per_cpu_ptr(lg->lock, i); + + rt_mutex_init(lock); + } +#endif LOCKDEP_INIT_MAP(&lg->lock_dep_map, name, &lg->lock_key, 0); } EXPORT_SYMBOL(lg_lock_init); void lg_local_lock(struct lglock *lg) { - arch_spinlock_t *lock; + lg_lock_ptr *lock; - preempt_disable(); + migrate_disable(); lock_acquire_shared(&lg->lock_dep_map, 0, 0, NULL, _RET_IP_); lock = this_cpu_ptr(lg->lock); - arch_spin_lock(lock); + lg_do_lock(lock); } EXPORT_SYMBOL(lg_local_lock); void lg_local_unlock(struct lglock *lg) { - arch_spinlock_t *lock; + lg_lock_ptr *lock; lock_release(&lg->lock_dep_map, 1, _RET_IP_); lock = this_cpu_ptr(lg->lock); - arch_spin_unlock(lock); - preempt_enable(); + lg_do_unlock(lock); + migrate_enable(); } EXPORT_SYMBOL(lg_local_unlock); void lg_local_lock_cpu(struct lglock *lg, int cpu) { - arch_spinlock_t *lock; + lg_lock_ptr *lock; - preempt_disable(); + preempt_disable_nort(); lock_acquire_shared(&lg->lock_dep_map, 0, 0, NULL, _RET_IP_); lock = per_cpu_ptr(lg->lock, cpu); - arch_spin_lock(lock); + lg_do_lock(lock); } EXPORT_SYMBOL(lg_local_lock_cpu); void lg_local_unlock_cpu(struct lglock *lg, int cpu) { - arch_spinlock_t *lock; + lg_lock_ptr *lock; lock_release(&lg->lock_dep_map, 1, _RET_IP_); lock = per_cpu_ptr(lg->lock, cpu); - arch_spin_unlock(lock); - preempt_enable(); + lg_do_unlock(lock); + preempt_enable_nort(); } EXPORT_SYMBOL(lg_local_unlock_cpu); @@ -64,12 +82,12 @@ { int i; - preempt_disable(); + preempt_disable_nort(); lock_acquire_exclusive(&lg->lock_dep_map, 0, 0, NULL, _RET_IP_); for_each_possible_cpu(i) { - arch_spinlock_t *lock; + lg_lock_ptr *lock; lock = per_cpu_ptr(lg->lock, i); - arch_spin_lock(lock); + lg_do_lock(lock); } } EXPORT_SYMBOL(lg_global_lock); @@ -80,10 +98,35 @@ lock_release(&lg->lock_dep_map, 1, _RET_IP_); for_each_possible_cpu(i) { - arch_spinlock_t *lock; + lg_lock_ptr *lock; lock = per_cpu_ptr(lg->lock, i); - arch_spin_unlock(lock); + lg_do_unlock(lock); } - preempt_enable(); + preempt_enable_nort(); } EXPORT_SYMBOL(lg_global_unlock); + +#ifdef CONFIG_PREEMPT_RT_FULL +/* + * HACK: If you use this, you get to keep the pieces. + * Used in queue_stop_cpus_work() when stop machinery + * is called from inactive CPU, so we can't schedule. + */ +# define lg_do_trylock_relax(l) \ + do { \ + while (!__rt_spin_trylock(l)) \ + cpu_relax(); \ + } while (0) + +void lg_global_trylock_relax(struct lglock *lg) +{ + int i; + + lock_acquire_exclusive(&lg->lock_dep_map, 0, 0, NULL, _RET_IP_); + for_each_possible_cpu(i) { + lg_lock_ptr *lock; + lock = per_cpu_ptr(lg->lock, i); + lg_do_trylock_relax(lock); + } +} +#endif diff -Nur linux-3.18.14.orig/kernel/locking/lockdep.c linux-3.18.14-rt/kernel/locking/lockdep.c --- linux-3.18.14.orig/kernel/locking/lockdep.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/locking/lockdep.c 2015-05-31 15:32:48.749635364 -0500 @@ -3542,6 +3542,7 @@ } } +#ifndef CONFIG_PREEMPT_RT_FULL /* * We dont accurately track softirq state in e.g. * hardirq contexts (such as on 4KSTACKS), so only @@ -3556,6 +3557,7 @@ DEBUG_LOCKS_WARN_ON(!current->softirqs_enabled); } } +#endif if (!debug_locks) print_irqtrace_events(current); diff -Nur linux-3.18.14.orig/kernel/locking/Makefile linux-3.18.14-rt/kernel/locking/Makefile --- linux-3.18.14.orig/kernel/locking/Makefile 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/locking/Makefile 2015-05-31 15:32:48.737635364 -0500 @@ -1,5 +1,5 @@ -obj-y += mutex.o semaphore.o rwsem.o mcs_spinlock.o +obj-y += semaphore.o mcs_spinlock.o ifdef CONFIG_FUNCTION_TRACER CFLAGS_REMOVE_lockdep.o = -pg @@ -8,7 +8,11 @@ CFLAGS_REMOVE_rtmutex-debug.o = -pg endif +ifneq ($(CONFIG_PREEMPT_RT_FULL),y) +obj-y += mutex.o obj-$(CONFIG_DEBUG_MUTEXES) += mutex-debug.o +obj-y += rwsem.o +endif obj-$(CONFIG_LOCKDEP) += lockdep.o ifeq ($(CONFIG_PROC_FS),y) obj-$(CONFIG_LOCKDEP) += lockdep_proc.o @@ -21,8 +25,11 @@ obj-$(CONFIG_RT_MUTEX_TESTER) += rtmutex-tester.o obj-$(CONFIG_DEBUG_SPINLOCK) += spinlock.o obj-$(CONFIG_DEBUG_SPINLOCK) += spinlock_debug.o +ifneq ($(CONFIG_PREEMPT_RT_FULL),y) obj-$(CONFIG_RWSEM_GENERIC_SPINLOCK) += rwsem-spinlock.o obj-$(CONFIG_RWSEM_XCHGADD_ALGORITHM) += rwsem-xadd.o +endif obj-$(CONFIG_PERCPU_RWSEM) += percpu-rwsem.o +obj-$(CONFIG_PREEMPT_RT_FULL) += rt.o obj-$(CONFIG_QUEUE_RWLOCK) += qrwlock.o obj-$(CONFIG_LOCK_TORTURE_TEST) += locktorture.o diff -Nur linux-3.18.14.orig/kernel/locking/percpu-rwsem.c linux-3.18.14-rt/kernel/locking/percpu-rwsem.c --- linux-3.18.14.orig/kernel/locking/percpu-rwsem.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/locking/percpu-rwsem.c 2015-05-31 15:32:48.757635364 -0500 @@ -84,8 +84,12 @@ down_read(&brw->rw_sem); atomic_inc(&brw->slow_read_ctr); +#ifdef CONFIG_PREEMPT_RT_FULL + up_read(&brw->rw_sem); +#else /* avoid up_read()->rwsem_release() */ __up_read(&brw->rw_sem); +#endif } void percpu_up_read(struct percpu_rw_semaphore *brw) diff -Nur linux-3.18.14.orig/kernel/locking/rt.c linux-3.18.14-rt/kernel/locking/rt.c --- linux-3.18.14.orig/kernel/locking/rt.c 1969-12-31 18:00:00.000000000 -0600 +++ linux-3.18.14-rt/kernel/locking/rt.c 2015-05-31 15:32:48.757635364 -0500 @@ -0,0 +1,456 @@ +/* + * kernel/rt.c + * + * Real-Time Preemption Support + * + * started by Ingo Molnar: + * + * Copyright (C) 2004-2006 Red Hat, Inc., Ingo Molnar + * Copyright (C) 2006, Timesys Corp., Thomas Gleixner + * + * historic credit for proving that Linux spinlocks can be implemented via + * RT-aware mutexes goes to many people: The Pmutex project (Dirk Grambow + * and others) who prototyped it on 2.4 and did lots of comparative + * research and analysis; TimeSys, for proving that you can implement a + * fully preemptible kernel via the use of IRQ threading and mutexes; + * Bill Huey for persuasively arguing on lkml that the mutex model is the + * right one; and to MontaVista, who ported pmutexes to 2.6. + * + * This code is a from-scratch implementation and is not based on pmutexes, + * but the idea of converting spinlocks to mutexes is used here too. + * + * lock debugging, locking tree, deadlock detection: + * + * Copyright (C) 2004, LynuxWorks, Inc., Igor Manyilov, Bill Huey + * Released under the General Public License (GPL). + * + * Includes portions of the generic R/W semaphore implementation from: + * + * Copyright (c) 2001 David Howells (dhowells@redhat.com). + * - Derived partially from idea by Andrea Arcangeli + * - Derived also from comments by Linus + * + * Pending ownership of locks and ownership stealing: + * + * Copyright (C) 2005, Kihon Technologies Inc., Steven Rostedt + * + * (also by Steven Rostedt) + * - Converted single pi_lock to individual task locks. + * + * By Esben Nielsen: + * Doing priority inheritance with help of the scheduler. + * + * Copyright (C) 2006, Timesys Corp., Thomas Gleixner + * - major rework based on Esben Nielsens initial patch + * - replaced thread_info references by task_struct refs + * - removed task->pending_owner dependency + * - BKL drop/reacquire for semaphore style locks to avoid deadlocks + * in the scheduler return path as discussed with Steven Rostedt + * + * Copyright (C) 2006, Kihon Technologies Inc. + * Steven Rostedt + * - debugged and patched Thomas Gleixner's rework. + * - added back the cmpxchg to the rework. + * - turned atomic require back on for SMP. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "rtmutex_common.h" + +/* + * struct mutex functions + */ +void __mutex_do_init(struct mutex *mutex, const char *name, + struct lock_class_key *key) +{ +#ifdef CONFIG_DEBUG_LOCK_ALLOC + /* + * Make sure we are not reinitializing a held lock: + */ + debug_check_no_locks_freed((void *)mutex, sizeof(*mutex)); + lockdep_init_map(&mutex->dep_map, name, key, 0); +#endif + mutex->lock.save_state = 0; +} +EXPORT_SYMBOL(__mutex_do_init); + +void __lockfunc _mutex_lock(struct mutex *lock) +{ + mutex_acquire(&lock->dep_map, 0, 0, _RET_IP_); + rt_mutex_lock(&lock->lock); +} +EXPORT_SYMBOL(_mutex_lock); + +int __lockfunc _mutex_lock_interruptible(struct mutex *lock) +{ + int ret; + + mutex_acquire(&lock->dep_map, 0, 0, _RET_IP_); + ret = rt_mutex_lock_interruptible(&lock->lock); + if (ret) + mutex_release(&lock->dep_map, 1, _RET_IP_); + return ret; +} +EXPORT_SYMBOL(_mutex_lock_interruptible); + +int __lockfunc _mutex_lock_killable(struct mutex *lock) +{ + int ret; + + mutex_acquire(&lock->dep_map, 0, 0, _RET_IP_); + ret = rt_mutex_lock_killable(&lock->lock); + if (ret) + mutex_release(&lock->dep_map, 1, _RET_IP_); + return ret; +} +EXPORT_SYMBOL(_mutex_lock_killable); + +#ifdef CONFIG_DEBUG_LOCK_ALLOC +void __lockfunc _mutex_lock_nested(struct mutex *lock, int subclass) +{ + mutex_acquire_nest(&lock->dep_map, subclass, 0, NULL, _RET_IP_); + rt_mutex_lock(&lock->lock); +} +EXPORT_SYMBOL(_mutex_lock_nested); + +void __lockfunc _mutex_lock_nest_lock(struct mutex *lock, struct lockdep_map *nest) +{ + mutex_acquire_nest(&lock->dep_map, 0, 0, nest, _RET_IP_); + rt_mutex_lock(&lock->lock); +} +EXPORT_SYMBOL(_mutex_lock_nest_lock); + +int __lockfunc _mutex_lock_interruptible_nested(struct mutex *lock, int subclass) +{ + int ret; + + mutex_acquire_nest(&lock->dep_map, subclass, 0, NULL, _RET_IP_); + ret = rt_mutex_lock_interruptible(&lock->lock); + if (ret) + mutex_release(&lock->dep_map, 1, _RET_IP_); + return ret; +} +EXPORT_SYMBOL(_mutex_lock_interruptible_nested); + +int __lockfunc _mutex_lock_killable_nested(struct mutex *lock, int subclass) +{ + int ret; + + mutex_acquire(&lock->dep_map, subclass, 0, _RET_IP_); + ret = rt_mutex_lock_killable(&lock->lock); + if (ret) + mutex_release(&lock->dep_map, 1, _RET_IP_); + return ret; +} +EXPORT_SYMBOL(_mutex_lock_killable_nested); +#endif + +int __lockfunc _mutex_trylock(struct mutex *lock) +{ + int ret = rt_mutex_trylock(&lock->lock); + + if (ret) + mutex_acquire(&lock->dep_map, 0, 1, _RET_IP_); + + return ret; +} +EXPORT_SYMBOL(_mutex_trylock); + +void __lockfunc _mutex_unlock(struct mutex *lock) +{ + mutex_release(&lock->dep_map, 1, _RET_IP_); + rt_mutex_unlock(&lock->lock); +} +EXPORT_SYMBOL(_mutex_unlock); + +/* + * rwlock_t functions + */ +int __lockfunc rt_write_trylock(rwlock_t *rwlock) +{ + int ret; + + migrate_disable(); + ret = rt_mutex_trylock(&rwlock->lock); + if (ret) + rwlock_acquire(&rwlock->dep_map, 0, 1, _RET_IP_); + else + migrate_enable(); + + return ret; +} +EXPORT_SYMBOL(rt_write_trylock); + +int __lockfunc rt_write_trylock_irqsave(rwlock_t *rwlock, unsigned long *flags) +{ + int ret; + + *flags = 0; + ret = rt_write_trylock(rwlock); + return ret; +} +EXPORT_SYMBOL(rt_write_trylock_irqsave); + +int __lockfunc rt_read_trylock(rwlock_t *rwlock) +{ + struct rt_mutex *lock = &rwlock->lock; + int ret = 1; + + /* + * recursive read locks succeed when current owns the lock, + * but not when read_depth == 0 which means that the lock is + * write locked. + */ + if (rt_mutex_owner(lock) != current) { + migrate_disable(); + ret = rt_mutex_trylock(lock); + if (ret) + rwlock_acquire(&rwlock->dep_map, 0, 1, _RET_IP_); + else + migrate_enable(); + + } else if (!rwlock->read_depth) { + ret = 0; + } + + if (ret) + rwlock->read_depth++; + + return ret; +} +EXPORT_SYMBOL(rt_read_trylock); + +void __lockfunc rt_write_lock(rwlock_t *rwlock) +{ + rwlock_acquire(&rwlock->dep_map, 0, 0, _RET_IP_); + migrate_disable(); + __rt_spin_lock(&rwlock->lock); +} +EXPORT_SYMBOL(rt_write_lock); + +void __lockfunc rt_read_lock(rwlock_t *rwlock) +{ + struct rt_mutex *lock = &rwlock->lock; + + + /* + * recursive read locks succeed when current owns the lock + */ + if (rt_mutex_owner(lock) != current) { + migrate_disable(); + rwlock_acquire(&rwlock->dep_map, 0, 0, _RET_IP_); + __rt_spin_lock(lock); + } + rwlock->read_depth++; +} + +EXPORT_SYMBOL(rt_read_lock); + +void __lockfunc rt_write_unlock(rwlock_t *rwlock) +{ + /* NOTE: we always pass in '1' for nested, for simplicity */ + rwlock_release(&rwlock->dep_map, 1, _RET_IP_); + __rt_spin_unlock(&rwlock->lock); + migrate_enable(); +} +EXPORT_SYMBOL(rt_write_unlock); + +void __lockfunc rt_read_unlock(rwlock_t *rwlock) +{ + /* Release the lock only when read_depth is down to 0 */ + if (--rwlock->read_depth == 0) { + rwlock_release(&rwlock->dep_map, 1, _RET_IP_); + __rt_spin_unlock(&rwlock->lock); + migrate_enable(); + } +} +EXPORT_SYMBOL(rt_read_unlock); + +unsigned long __lockfunc rt_write_lock_irqsave(rwlock_t *rwlock) +{ + rt_write_lock(rwlock); + + return 0; +} +EXPORT_SYMBOL(rt_write_lock_irqsave); + +unsigned long __lockfunc rt_read_lock_irqsave(rwlock_t *rwlock) +{ + rt_read_lock(rwlock); + + return 0; +} +EXPORT_SYMBOL(rt_read_lock_irqsave); + +void __rt_rwlock_init(rwlock_t *rwlock, char *name, struct lock_class_key *key) +{ +#ifdef CONFIG_DEBUG_LOCK_ALLOC + /* + * Make sure we are not reinitializing a held lock: + */ + debug_check_no_locks_freed((void *)rwlock, sizeof(*rwlock)); + lockdep_init_map(&rwlock->dep_map, name, key, 0); +#endif + rwlock->lock.save_state = 1; + rwlock->read_depth = 0; +} +EXPORT_SYMBOL(__rt_rwlock_init); + +/* + * rw_semaphores + */ + +void rt_up_write(struct rw_semaphore *rwsem) +{ + rwsem_release(&rwsem->dep_map, 1, _RET_IP_); + rt_mutex_unlock(&rwsem->lock); +} +EXPORT_SYMBOL(rt_up_write); + +void rt_up_read(struct rw_semaphore *rwsem) +{ + rwsem_release(&rwsem->dep_map, 1, _RET_IP_); + if (--rwsem->read_depth == 0) + rt_mutex_unlock(&rwsem->lock); +} +EXPORT_SYMBOL(rt_up_read); + +/* + * downgrade a write lock into a read lock + * - just wake up any readers at the front of the queue + */ +void rt_downgrade_write(struct rw_semaphore *rwsem) +{ + BUG_ON(rt_mutex_owner(&rwsem->lock) != current); + rwsem->read_depth = 1; +} +EXPORT_SYMBOL(rt_downgrade_write); + +int rt_down_write_trylock(struct rw_semaphore *rwsem) +{ + int ret = rt_mutex_trylock(&rwsem->lock); + + if (ret) + rwsem_acquire(&rwsem->dep_map, 0, 1, _RET_IP_); + return ret; +} +EXPORT_SYMBOL(rt_down_write_trylock); + +void rt_down_write(struct rw_semaphore *rwsem) +{ + rwsem_acquire(&rwsem->dep_map, 0, 0, _RET_IP_); + rt_mutex_lock(&rwsem->lock); +} +EXPORT_SYMBOL(rt_down_write); + +void rt_down_write_nested(struct rw_semaphore *rwsem, int subclass) +{ + rwsem_acquire(&rwsem->dep_map, subclass, 0, _RET_IP_); + rt_mutex_lock(&rwsem->lock); +} +EXPORT_SYMBOL(rt_down_write_nested); + +void rt_down_write_nested_lock(struct rw_semaphore *rwsem, + struct lockdep_map *nest) +{ + rwsem_acquire_nest(&rwsem->dep_map, 0, 0, nest, _RET_IP_); + rt_mutex_lock(&rwsem->lock); +} +EXPORT_SYMBOL(rt_down_write_nested_lock); + +int rt_down_read_trylock(struct rw_semaphore *rwsem) +{ + struct rt_mutex *lock = &rwsem->lock; + int ret = 1; + + /* + * recursive read locks succeed when current owns the rwsem, + * but not when read_depth == 0 which means that the rwsem is + * write locked. + */ + if (rt_mutex_owner(lock) != current) + ret = rt_mutex_trylock(&rwsem->lock); + else if (!rwsem->read_depth) + ret = 0; + + if (ret) { + rwsem->read_depth++; + rwsem_acquire(&rwsem->dep_map, 0, 1, _RET_IP_); + } + return ret; +} +EXPORT_SYMBOL(rt_down_read_trylock); + +static void __rt_down_read(struct rw_semaphore *rwsem, int subclass) +{ + struct rt_mutex *lock = &rwsem->lock; + + rwsem_acquire_read(&rwsem->dep_map, subclass, 0, _RET_IP_); + + if (rt_mutex_owner(lock) != current) + rt_mutex_lock(&rwsem->lock); + rwsem->read_depth++; +} + +void rt_down_read(struct rw_semaphore *rwsem) +{ + __rt_down_read(rwsem, 0); +} +EXPORT_SYMBOL(rt_down_read); + +void rt_down_read_nested(struct rw_semaphore *rwsem, int subclass) +{ + __rt_down_read(rwsem, subclass); +} +EXPORT_SYMBOL(rt_down_read_nested); + +void __rt_rwsem_init(struct rw_semaphore *rwsem, const char *name, + struct lock_class_key *key) +{ +#ifdef CONFIG_DEBUG_LOCK_ALLOC + /* + * Make sure we are not reinitializing a held lock: + */ + debug_check_no_locks_freed((void *)rwsem, sizeof(*rwsem)); + lockdep_init_map(&rwsem->dep_map, name, key, 0); +#endif + rwsem->read_depth = 0; + rwsem->lock.save_state = 0; +} +EXPORT_SYMBOL(__rt_rwsem_init); + +/** + * atomic_dec_and_mutex_lock - return holding mutex if we dec to 0 + * @cnt: the atomic which we are to dec + * @lock: the mutex to return holding if we dec to 0 + * + * return true and hold lock if we dec to 0, return false otherwise + */ +int atomic_dec_and_mutex_lock(atomic_t *cnt, struct mutex *lock) +{ + /* dec if we can't possibly hit 0 */ + if (atomic_add_unless(cnt, -1, 1)) + return 0; + /* we might hit 0, so take the lock */ + mutex_lock(lock); + if (!atomic_dec_and_test(cnt)) { + /* when we actually did the dec, we didn't hit 0 */ + mutex_unlock(lock); + return 0; + } + /* we hit 0, and we hold the lock */ + return 1; +} +EXPORT_SYMBOL(atomic_dec_and_mutex_lock); diff -Nur linux-3.18.14.orig/kernel/locking/rtmutex.c linux-3.18.14-rt/kernel/locking/rtmutex.c --- linux-3.18.14.orig/kernel/locking/rtmutex.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/locking/rtmutex.c 2015-05-31 15:32:48.769635364 -0500 @@ -7,6 +7,11 @@ * Copyright (C) 2005-2006 Timesys Corp., Thomas Gleixner * Copyright (C) 2005 Kihon Technologies Inc., Steven Rostedt * Copyright (C) 2006 Esben Nielsen + * Adaptive Spinlocks: + * Copyright (C) 2008 Novell, Inc., Gregory Haskins, Sven Dietrich, + * and Peter Morreale, + * Adaptive Spinlocks simplification: + * Copyright (C) 2008 Red Hat, Inc., Steven Rostedt * * See Documentation/locking/rt-mutex-design.txt for details. */ @@ -16,6 +21,7 @@ #include #include #include +#include #include "rtmutex_common.h" @@ -69,6 +75,12 @@ clear_rt_mutex_waiters(lock); } +static int rt_mutex_real_waiter(struct rt_mutex_waiter *waiter) +{ + return waiter && waiter != PI_WAKEUP_INPROGRESS && + waiter != PI_REQUEUE_INPROGRESS; +} + /* * We can speed up the acquire/release, if the architecture * supports cmpxchg and if there's no debugging state to be set up @@ -333,6 +345,14 @@ return debug_rt_mutex_detect_deadlock(waiter, chwalk); } +static void rt_mutex_wake_waiter(struct rt_mutex_waiter *waiter) +{ + if (waiter->savestate) + wake_up_lock_sleeper(waiter->task); + else + wake_up_process(waiter->task); +} + /* * Max number of times we'll walk the boosting chain: */ @@ -340,7 +360,8 @@ static inline struct rt_mutex *task_blocked_on_lock(struct task_struct *p) { - return p->pi_blocked_on ? p->pi_blocked_on->lock : NULL; + return rt_mutex_real_waiter(p->pi_blocked_on) ? + p->pi_blocked_on->lock : NULL; } /* @@ -477,7 +498,7 @@ * reached or the state of the chain has changed while we * dropped the locks. */ - if (!waiter) + if (!rt_mutex_real_waiter(waiter)) goto out_unlock_pi; /* @@ -639,13 +660,16 @@ * follow here. This is the end of the chain we are walking. */ if (!rt_mutex_owner(lock)) { + struct rt_mutex_waiter *lock_top_waiter; + /* * If the requeue [7] above changed the top waiter, * then we need to wake the new top waiter up to try * to get the lock. */ - if (prerequeue_top_waiter != rt_mutex_top_waiter(lock)) - wake_up_process(rt_mutex_top_waiter(lock)->task); + lock_top_waiter = rt_mutex_top_waiter(lock); + if (prerequeue_top_waiter != lock_top_waiter) + rt_mutex_wake_waiter(lock_top_waiter); raw_spin_unlock(&lock->wait_lock); return 0; } @@ -738,6 +762,25 @@ return ret; } + +#define STEAL_NORMAL 0 +#define STEAL_LATERAL 1 + +/* + * Note that RT tasks are excluded from lateral-steals to prevent the + * introduction of an unbounded latency + */ +static inline int lock_is_stealable(struct task_struct *task, + struct task_struct *pendowner, int mode) +{ + if (mode == STEAL_NORMAL || rt_task(task)) { + if (task->prio >= pendowner->prio) + return 0; + } else if (task->prio > pendowner->prio) + return 0; + return 1; +} + /* * Try to take an rt-mutex * @@ -748,8 +791,9 @@ * @waiter: The waiter that is queued to the lock's wait list if the * callsite called task_blocked_on_lock(), otherwise NULL */ -static int try_to_take_rt_mutex(struct rt_mutex *lock, struct task_struct *task, - struct rt_mutex_waiter *waiter) +static int __try_to_take_rt_mutex(struct rt_mutex *lock, + struct task_struct *task, + struct rt_mutex_waiter *waiter, int mode) { unsigned long flags; @@ -788,8 +832,10 @@ * If waiter is not the highest priority waiter of * @lock, give up. */ - if (waiter != rt_mutex_top_waiter(lock)) + if (waiter != rt_mutex_top_waiter(lock)) { + /* XXX lock_is_stealable() ? */ return 0; + } /* * We can acquire the lock. Remove the waiter from the @@ -807,14 +853,10 @@ * not need to be dequeued. */ if (rt_mutex_has_waiters(lock)) { - /* - * If @task->prio is greater than or equal to - * the top waiter priority (kernel view), - * @task lost. - */ - if (task->prio >= rt_mutex_top_waiter(lock)->prio) - return 0; + struct task_struct *pown = rt_mutex_top_waiter(lock)->task; + if (task != pown && !lock_is_stealable(task, pown, mode)) + return 0; /* * The current top waiter stays enqueued. We * don't have to change anything in the lock @@ -863,6 +905,369 @@ return 1; } +#ifdef CONFIG_PREEMPT_RT_FULL +/* + * preemptible spin_lock functions: + */ +static inline void rt_spin_lock_fastlock(struct rt_mutex *lock, + void (*slowfn)(struct rt_mutex *lock)) +{ + might_sleep(); + + if (likely(rt_mutex_cmpxchg(lock, NULL, current))) + rt_mutex_deadlock_account_lock(lock, current); + else + slowfn(lock); +} + +static inline void rt_spin_lock_fastunlock(struct rt_mutex *lock, + void (*slowfn)(struct rt_mutex *lock)) +{ + if (likely(rt_mutex_cmpxchg(lock, current, NULL))) + rt_mutex_deadlock_account_unlock(current); + else + slowfn(lock); +} +#ifdef CONFIG_SMP +/* + * Note that owner is a speculative pointer and dereferencing relies + * on rcu_read_lock() and the check against the lock owner. + */ +static int adaptive_wait(struct rt_mutex *lock, + struct task_struct *owner) +{ + int res = 0; + + rcu_read_lock(); + for (;;) { + if (owner != rt_mutex_owner(lock)) + break; + /* + * Ensure that owner->on_cpu is dereferenced _after_ + * checking the above to be valid. + */ + barrier(); + if (!owner->on_cpu) { + res = 1; + break; + } + cpu_relax(); + } + rcu_read_unlock(); + return res; +} +#else +static int adaptive_wait(struct rt_mutex *lock, + struct task_struct *orig_owner) +{ + return 1; +} +#endif + +# define pi_lock(lock) raw_spin_lock_irq(lock) +# define pi_unlock(lock) raw_spin_unlock_irq(lock) + +static int task_blocks_on_rt_mutex(struct rt_mutex *lock, + struct rt_mutex_waiter *waiter, + struct task_struct *task, + enum rtmutex_chainwalk chwalk); +/* + * Slow path lock function spin_lock style: this variant is very + * careful not to miss any non-lock wakeups. + * + * We store the current state under p->pi_lock in p->saved_state and + * the try_to_wake_up() code handles this accordingly. + */ +static void noinline __sched rt_spin_lock_slowlock(struct rt_mutex *lock) +{ + struct task_struct *lock_owner, *self = current; + struct rt_mutex_waiter waiter, *top_waiter; + int ret; + + rt_mutex_init_waiter(&waiter, true); + + raw_spin_lock(&lock->wait_lock); + + if (__try_to_take_rt_mutex(lock, self, NULL, STEAL_LATERAL)) { + raw_spin_unlock(&lock->wait_lock); + return; + } + + BUG_ON(rt_mutex_owner(lock) == self); + + /* + * We save whatever state the task is in and we'll restore it + * after acquiring the lock taking real wakeups into account + * as well. We are serialized via pi_lock against wakeups. See + * try_to_wake_up(). + */ + pi_lock(&self->pi_lock); + self->saved_state = self->state; + __set_current_state(TASK_UNINTERRUPTIBLE); + pi_unlock(&self->pi_lock); + + ret = task_blocks_on_rt_mutex(lock, &waiter, self, 0); + BUG_ON(ret); + + for (;;) { + /* Try to acquire the lock again. */ + if (__try_to_take_rt_mutex(lock, self, &waiter, STEAL_LATERAL)) + break; + + top_waiter = rt_mutex_top_waiter(lock); + lock_owner = rt_mutex_owner(lock); + + raw_spin_unlock(&lock->wait_lock); + + debug_rt_mutex_print_deadlock(&waiter); + + if (top_waiter != &waiter || adaptive_wait(lock, lock_owner)) + schedule_rt_mutex(lock); + + raw_spin_lock(&lock->wait_lock); + + pi_lock(&self->pi_lock); + __set_current_state(TASK_UNINTERRUPTIBLE); + pi_unlock(&self->pi_lock); + } + + /* + * Restore the task state to current->saved_state. We set it + * to the original state above and the try_to_wake_up() code + * has possibly updated it when a real (non-rtmutex) wakeup + * happened while we were blocked. Clear saved_state so + * try_to_wakeup() does not get confused. + */ + pi_lock(&self->pi_lock); + __set_current_state(self->saved_state); + self->saved_state = TASK_RUNNING; + pi_unlock(&self->pi_lock); + + /* + * try_to_take_rt_mutex() sets the waiter bit + * unconditionally. We might have to fix that up: + */ + fixup_rt_mutex_waiters(lock); + + BUG_ON(rt_mutex_has_waiters(lock) && &waiter == rt_mutex_top_waiter(lock)); + BUG_ON(!RB_EMPTY_NODE(&waiter.tree_entry)); + + raw_spin_unlock(&lock->wait_lock); + + debug_rt_mutex_free_waiter(&waiter); +} + +static void wakeup_next_waiter(struct rt_mutex *lock); +/* + * Slow path to release a rt_mutex spin_lock style + */ +static void __sched __rt_spin_lock_slowunlock(struct rt_mutex *lock) +{ + debug_rt_mutex_unlock(lock); + + rt_mutex_deadlock_account_unlock(current); + + if (!rt_mutex_has_waiters(lock)) { + lock->owner = NULL; + raw_spin_unlock(&lock->wait_lock); + return; + } + + wakeup_next_waiter(lock); + + raw_spin_unlock(&lock->wait_lock); + + /* Undo pi boosting.when necessary */ + rt_mutex_adjust_prio(current); +} + +static void noinline __sched rt_spin_lock_slowunlock(struct rt_mutex *lock) +{ + raw_spin_lock(&lock->wait_lock); + __rt_spin_lock_slowunlock(lock); +} + +static void noinline __sched rt_spin_lock_slowunlock_hirq(struct rt_mutex *lock) +{ + int ret; + + do { + ret = raw_spin_trylock(&lock->wait_lock); + } while (!ret); + + __rt_spin_lock_slowunlock(lock); +} + +void __lockfunc rt_spin_lock(spinlock_t *lock) +{ + rt_spin_lock_fastlock(&lock->lock, rt_spin_lock_slowlock); + spin_acquire(&lock->dep_map, 0, 0, _RET_IP_); +} +EXPORT_SYMBOL(rt_spin_lock); + +void __lockfunc __rt_spin_lock(struct rt_mutex *lock) +{ + rt_spin_lock_fastlock(lock, rt_spin_lock_slowlock); +} +EXPORT_SYMBOL(__rt_spin_lock); + +#ifdef CONFIG_DEBUG_LOCK_ALLOC +void __lockfunc rt_spin_lock_nested(spinlock_t *lock, int subclass) +{ + rt_spin_lock_fastlock(&lock->lock, rt_spin_lock_slowlock); + spin_acquire(&lock->dep_map, subclass, 0, _RET_IP_); +} +EXPORT_SYMBOL(rt_spin_lock_nested); +#endif + +void __lockfunc rt_spin_unlock(spinlock_t *lock) +{ + /* NOTE: we always pass in '1' for nested, for simplicity */ + spin_release(&lock->dep_map, 1, _RET_IP_); + rt_spin_lock_fastunlock(&lock->lock, rt_spin_lock_slowunlock); +} +EXPORT_SYMBOL(rt_spin_unlock); + +void __lockfunc rt_spin_unlock_after_trylock_in_irq(spinlock_t *lock) +{ + /* NOTE: we always pass in '1' for nested, for simplicity */ + spin_release(&lock->dep_map, 1, _RET_IP_); + rt_spin_lock_fastunlock(&lock->lock, rt_spin_lock_slowunlock_hirq); +} + +void __lockfunc __rt_spin_unlock(struct rt_mutex *lock) +{ + rt_spin_lock_fastunlock(lock, rt_spin_lock_slowunlock); +} +EXPORT_SYMBOL(__rt_spin_unlock); + +/* + * Wait for the lock to get unlocked: instead of polling for an unlock + * (like raw spinlocks do), we lock and unlock, to force the kernel to + * schedule if there's contention: + */ +void __lockfunc rt_spin_unlock_wait(spinlock_t *lock) +{ + spin_lock(lock); + spin_unlock(lock); +} +EXPORT_SYMBOL(rt_spin_unlock_wait); + +int __lockfunc __rt_spin_trylock(struct rt_mutex *lock) +{ + return rt_mutex_trylock(lock); +} + +int __lockfunc rt_spin_trylock(spinlock_t *lock) +{ + int ret = rt_mutex_trylock(&lock->lock); + + if (ret) + spin_acquire(&lock->dep_map, 0, 1, _RET_IP_); + return ret; +} +EXPORT_SYMBOL(rt_spin_trylock); + +int __lockfunc rt_spin_trylock_bh(spinlock_t *lock) +{ + int ret; + + local_bh_disable(); + ret = rt_mutex_trylock(&lock->lock); + if (ret) { + migrate_disable(); + spin_acquire(&lock->dep_map, 0, 1, _RET_IP_); + } else + local_bh_enable(); + return ret; +} +EXPORT_SYMBOL(rt_spin_trylock_bh); + +int __lockfunc rt_spin_trylock_irqsave(spinlock_t *lock, unsigned long *flags) +{ + int ret; + + *flags = 0; + ret = rt_mutex_trylock(&lock->lock); + if (ret) { + migrate_disable(); + spin_acquire(&lock->dep_map, 0, 1, _RET_IP_); + } + return ret; +} +EXPORT_SYMBOL(rt_spin_trylock_irqsave); + +int atomic_dec_and_spin_lock(atomic_t *atomic, spinlock_t *lock) +{ + /* Subtract 1 from counter unless that drops it to 0 (ie. it was 1) */ + if (atomic_add_unless(atomic, -1, 1)) + return 0; + migrate_disable(); + rt_spin_lock(lock); + if (atomic_dec_and_test(atomic)) + return 1; + rt_spin_unlock(lock); + migrate_enable(); + return 0; +} +EXPORT_SYMBOL(atomic_dec_and_spin_lock); + + void +__rt_spin_lock_init(spinlock_t *lock, char *name, struct lock_class_key *key) +{ +#ifdef CONFIG_DEBUG_LOCK_ALLOC + /* + * Make sure we are not reinitializing a held lock: + */ + debug_check_no_locks_freed((void *)lock, sizeof(*lock)); + lockdep_init_map(&lock->dep_map, name, key, 0); +#endif +} +EXPORT_SYMBOL(__rt_spin_lock_init); + +#endif /* PREEMPT_RT_FULL */ + +#ifdef CONFIG_PREEMPT_RT_FULL + static inline int __sched +__mutex_lock_check_stamp(struct rt_mutex *lock, struct ww_acquire_ctx *ctx) +{ + struct ww_mutex *ww = container_of(lock, struct ww_mutex, base.lock); + struct ww_acquire_ctx *hold_ctx = ACCESS_ONCE(ww->ctx); + + if (!hold_ctx) + return 0; + + if (unlikely(ctx == hold_ctx)) + return -EALREADY; + + if (ctx->stamp - hold_ctx->stamp <= LONG_MAX && + (ctx->stamp != hold_ctx->stamp || ctx > hold_ctx)) { +#ifdef CONFIG_DEBUG_MUTEXES + DEBUG_LOCKS_WARN_ON(ctx->contending_lock); + ctx->contending_lock = ww; +#endif + return -EDEADLK; + } + + return 0; +} +#else + static inline int __sched +__mutex_lock_check_stamp(struct rt_mutex *lock, struct ww_acquire_ctx *ctx) +{ + BUG(); + return 0; +} + +#endif + +static inline int +try_to_take_rt_mutex(struct rt_mutex *lock, struct task_struct *task, + struct rt_mutex_waiter *waiter) +{ + return __try_to_take_rt_mutex(lock, task, waiter, STEAL_NORMAL); +} + /* * Task blocks on lock. * @@ -894,6 +1299,23 @@ return -EDEADLK; raw_spin_lock_irqsave(&task->pi_lock, flags); + + /* + * In the case of futex requeue PI, this will be a proxy + * lock. The task will wake unaware that it is enqueueed on + * this lock. Avoid blocking on two locks and corrupting + * pi_blocked_on via the PI_WAKEUP_INPROGRESS + * flag. futex_wait_requeue_pi() sets this when it wakes up + * before requeue (due to a signal or timeout). Do not enqueue + * the task if PI_WAKEUP_INPROGRESS is set. + */ + if (task != current && task->pi_blocked_on == PI_WAKEUP_INPROGRESS) { + raw_spin_unlock_irqrestore(&task->pi_lock, flags); + return -EAGAIN; + } + + BUG_ON(rt_mutex_real_waiter(task->pi_blocked_on)); + __rt_mutex_adjust_prio(task); waiter->task = task; waiter->lock = lock; @@ -917,7 +1339,7 @@ rt_mutex_enqueue_pi(owner, waiter); __rt_mutex_adjust_prio(owner); - if (owner->pi_blocked_on) + if (rt_mutex_real_waiter(owner->pi_blocked_on)) chain_walk = 1; } else if (rt_mutex_cond_detect_deadlock(waiter, chwalk)) { chain_walk = 1; @@ -994,7 +1416,7 @@ * long as we hold lock->wait_lock. The waiter task needs to * acquire it in order to dequeue the waiter. */ - wake_up_process(waiter->task); + rt_mutex_wake_waiter(waiter); } /* @@ -1008,7 +1430,7 @@ { bool is_top_waiter = (waiter == rt_mutex_top_waiter(lock)); struct task_struct *owner = rt_mutex_owner(lock); - struct rt_mutex *next_lock; + struct rt_mutex *next_lock = NULL; unsigned long flags; raw_spin_lock_irqsave(¤t->pi_lock, flags); @@ -1033,7 +1455,8 @@ __rt_mutex_adjust_prio(owner); /* Store the lock on which owner is blocked or NULL */ - next_lock = task_blocked_on_lock(owner); + if (rt_mutex_real_waiter(owner->pi_blocked_on)) + next_lock = task_blocked_on_lock(owner); raw_spin_unlock_irqrestore(&owner->pi_lock, flags); @@ -1069,17 +1492,17 @@ raw_spin_lock_irqsave(&task->pi_lock, flags); waiter = task->pi_blocked_on; - if (!waiter || (waiter->prio == task->prio && + if (!rt_mutex_real_waiter(waiter) || (waiter->prio == task->prio && !dl_prio(task->prio))) { raw_spin_unlock_irqrestore(&task->pi_lock, flags); return; } next_lock = waiter->lock; - raw_spin_unlock_irqrestore(&task->pi_lock, flags); /* gets dropped in rt_mutex_adjust_prio_chain()! */ get_task_struct(task); + raw_spin_unlock_irqrestore(&task->pi_lock, flags); rt_mutex_adjust_prio_chain(task, RT_MUTEX_MIN_CHAINWALK, NULL, next_lock, NULL, task); } @@ -1097,7 +1520,8 @@ static int __sched __rt_mutex_slowlock(struct rt_mutex *lock, int state, struct hrtimer_sleeper *timeout, - struct rt_mutex_waiter *waiter) + struct rt_mutex_waiter *waiter, + struct ww_acquire_ctx *ww_ctx) { int ret = 0; @@ -1120,6 +1544,12 @@ break; } + if (ww_ctx && ww_ctx->acquired > 0) { + ret = __mutex_lock_check_stamp(lock, ww_ctx); + if (ret) + break; + } + raw_spin_unlock(&lock->wait_lock); debug_rt_mutex_print_deadlock(waiter); @@ -1153,25 +1583,102 @@ } } +static __always_inline void ww_mutex_lock_acquired(struct ww_mutex *ww, + struct ww_acquire_ctx *ww_ctx) +{ +#ifdef CONFIG_DEBUG_MUTEXES + /* + * If this WARN_ON triggers, you used ww_mutex_lock to acquire, + * but released with a normal mutex_unlock in this call. + * + * This should never happen, always use ww_mutex_unlock. + */ + DEBUG_LOCKS_WARN_ON(ww->ctx); + + /* + * Not quite done after calling ww_acquire_done() ? + */ + DEBUG_LOCKS_WARN_ON(ww_ctx->done_acquire); + + if (ww_ctx->contending_lock) { + /* + * After -EDEADLK you tried to + * acquire a different ww_mutex? Bad! + */ + DEBUG_LOCKS_WARN_ON(ww_ctx->contending_lock != ww); + + /* + * You called ww_mutex_lock after receiving -EDEADLK, + * but 'forgot' to unlock everything else first? + */ + DEBUG_LOCKS_WARN_ON(ww_ctx->acquired > 0); + ww_ctx->contending_lock = NULL; + } + + /* + * Naughty, using a different class will lead to undefined behavior! + */ + DEBUG_LOCKS_WARN_ON(ww_ctx->ww_class != ww->ww_class); +#endif + ww_ctx->acquired++; +} + +#ifdef CONFIG_PREEMPT_RT_FULL +static void ww_mutex_account_lock(struct rt_mutex *lock, + struct ww_acquire_ctx *ww_ctx) +{ + struct ww_mutex *ww = container_of(lock, struct ww_mutex, base.lock); + struct rt_mutex_waiter *waiter, *n; + + /* + * This branch gets optimized out for the common case, + * and is only important for ww_mutex_lock. + */ + ww_mutex_lock_acquired(ww, ww_ctx); + ww->ctx = ww_ctx; + + /* + * Give any possible sleeping processes the chance to wake up, + * so they can recheck if they have to back off. + */ + rbtree_postorder_for_each_entry_safe(waiter, n, &lock->waiters, + tree_entry) { + /* XXX debug rt mutex waiter wakeup */ + + BUG_ON(waiter->lock != lock); + rt_mutex_wake_waiter(waiter); + } +} + +#else + +static void ww_mutex_account_lock(struct rt_mutex *lock, + struct ww_acquire_ctx *ww_ctx) +{ + BUG(); +} +#endif + /* * Slow path lock function: */ static int __sched rt_mutex_slowlock(struct rt_mutex *lock, int state, struct hrtimer_sleeper *timeout, - enum rtmutex_chainwalk chwalk) + enum rtmutex_chainwalk chwalk, + struct ww_acquire_ctx *ww_ctx) { struct rt_mutex_waiter waiter; int ret = 0; - debug_rt_mutex_init_waiter(&waiter); - RB_CLEAR_NODE(&waiter.pi_tree_entry); - RB_CLEAR_NODE(&waiter.tree_entry); + rt_mutex_init_waiter(&waiter, false); raw_spin_lock(&lock->wait_lock); /* Try to acquire the lock again: */ if (try_to_take_rt_mutex(lock, current, NULL)) { + if (ww_ctx) + ww_mutex_account_lock(lock, ww_ctx); raw_spin_unlock(&lock->wait_lock); return 0; } @@ -1188,14 +1695,23 @@ ret = task_blocks_on_rt_mutex(lock, &waiter, current, chwalk); if (likely(!ret)) - ret = __rt_mutex_slowlock(lock, state, timeout, &waiter); + ret = __rt_mutex_slowlock(lock, state, timeout, &waiter, ww_ctx); + else if (ww_ctx) { + /* ww_mutex received EDEADLK, let it become EALREADY */ + ret = __mutex_lock_check_stamp(lock, ww_ctx); + BUG_ON(!ret); + } set_current_state(TASK_RUNNING); if (unlikely(ret)) { if (rt_mutex_has_waiters(lock)) remove_waiter(lock, &waiter); - rt_mutex_handle_deadlock(ret, chwalk, &waiter); + /* ww_mutex want to report EDEADLK/EALREADY, let them */ + if (!ww_ctx) + rt_mutex_handle_deadlock(ret, chwalk, &waiter); + } else if (ww_ctx) { + ww_mutex_account_lock(lock, ww_ctx); } /* @@ -1234,7 +1750,8 @@ * The mutex has currently no owner. Lock the wait lock and * try to acquire the lock. */ - raw_spin_lock(&lock->wait_lock); + if (!raw_spin_trylock(&lock->wait_lock)) + return 0; ret = try_to_take_rt_mutex(lock, current, NULL); @@ -1320,31 +1837,36 @@ */ static inline int rt_mutex_fastlock(struct rt_mutex *lock, int state, + struct ww_acquire_ctx *ww_ctx, int (*slowfn)(struct rt_mutex *lock, int state, struct hrtimer_sleeper *timeout, - enum rtmutex_chainwalk chwalk)) + enum rtmutex_chainwalk chwalk, + struct ww_acquire_ctx *ww_ctx)) { if (likely(rt_mutex_cmpxchg(lock, NULL, current))) { rt_mutex_deadlock_account_lock(lock, current); return 0; } else - return slowfn(lock, state, NULL, RT_MUTEX_MIN_CHAINWALK); + return slowfn(lock, state, NULL, RT_MUTEX_MIN_CHAINWALK, + ww_ctx); } static inline int rt_mutex_timed_fastlock(struct rt_mutex *lock, int state, struct hrtimer_sleeper *timeout, enum rtmutex_chainwalk chwalk, + struct ww_acquire_ctx *ww_ctx, int (*slowfn)(struct rt_mutex *lock, int state, struct hrtimer_sleeper *timeout, - enum rtmutex_chainwalk chwalk)) + enum rtmutex_chainwalk chwalk, + struct ww_acquire_ctx *ww_ctx)) { if (chwalk == RT_MUTEX_MIN_CHAINWALK && likely(rt_mutex_cmpxchg(lock, NULL, current))) { rt_mutex_deadlock_account_lock(lock, current); return 0; } else - return slowfn(lock, state, timeout, chwalk); + return slowfn(lock, state, timeout, chwalk, ww_ctx); } static inline int @@ -1377,7 +1899,7 @@ { might_sleep(); - rt_mutex_fastlock(lock, TASK_UNINTERRUPTIBLE, rt_mutex_slowlock); + rt_mutex_fastlock(lock, TASK_UNINTERRUPTIBLE, NULL, rt_mutex_slowlock); } EXPORT_SYMBOL_GPL(rt_mutex_lock); @@ -1394,7 +1916,7 @@ { might_sleep(); - return rt_mutex_fastlock(lock, TASK_INTERRUPTIBLE, rt_mutex_slowlock); + return rt_mutex_fastlock(lock, TASK_INTERRUPTIBLE, NULL, rt_mutex_slowlock); } EXPORT_SYMBOL_GPL(rt_mutex_lock_interruptible); @@ -1407,11 +1929,30 @@ might_sleep(); return rt_mutex_timed_fastlock(lock, TASK_INTERRUPTIBLE, timeout, - RT_MUTEX_FULL_CHAINWALK, + RT_MUTEX_FULL_CHAINWALK, NULL, rt_mutex_slowlock); } /** + * rt_mutex_lock_killable - lock a rt_mutex killable + * + * @lock: the rt_mutex to be locked + * @detect_deadlock: deadlock detection on/off + * + * Returns: + * 0 on success + * -EINTR when interrupted by a signal + * -EDEADLK when the lock would deadlock (when deadlock detection is on) + */ +int __sched rt_mutex_lock_killable(struct rt_mutex *lock) +{ + might_sleep(); + + return rt_mutex_fastlock(lock, TASK_KILLABLE, NULL, rt_mutex_slowlock); +} +EXPORT_SYMBOL_GPL(rt_mutex_lock_killable); + +/** * rt_mutex_timed_lock - lock a rt_mutex interruptible * the timeout structure is provided * by the caller @@ -1431,6 +1972,7 @@ return rt_mutex_timed_fastlock(lock, TASK_INTERRUPTIBLE, timeout, RT_MUTEX_MIN_CHAINWALK, + NULL, rt_mutex_slowlock); } EXPORT_SYMBOL_GPL(rt_mutex_timed_lock); @@ -1489,13 +2031,12 @@ void __rt_mutex_init(struct rt_mutex *lock, const char *name) { lock->owner = NULL; - raw_spin_lock_init(&lock->wait_lock); lock->waiters = RB_ROOT; lock->waiters_leftmost = NULL; debug_rt_mutex_init(lock, name); } -EXPORT_SYMBOL_GPL(__rt_mutex_init); +EXPORT_SYMBOL(__rt_mutex_init); /** * rt_mutex_init_proxy_locked - initialize and lock a rt_mutex on behalf of a @@ -1510,7 +2051,7 @@ void rt_mutex_init_proxy_locked(struct rt_mutex *lock, struct task_struct *proxy_owner) { - __rt_mutex_init(lock, NULL); + rt_mutex_init(lock); debug_rt_mutex_proxy_lock(lock, proxy_owner); rt_mutex_set_owner(lock, proxy_owner); rt_mutex_deadlock_account_lock(lock, proxy_owner); @@ -1558,6 +2099,35 @@ return 1; } +#ifdef CONFIG_PREEMPT_RT_FULL + /* + * In PREEMPT_RT there's an added race. + * If the task, that we are about to requeue, times out, + * it can set the PI_WAKEUP_INPROGRESS. This tells the requeue + * to skip this task. But right after the task sets + * its pi_blocked_on to PI_WAKEUP_INPROGRESS it can then + * block on the spin_lock(&hb->lock), which in RT is an rtmutex. + * This will replace the PI_WAKEUP_INPROGRESS with the actual + * lock that it blocks on. We *must not* place this task + * on this proxy lock in that case. + * + * To prevent this race, we first take the task's pi_lock + * and check if it has updated its pi_blocked_on. If it has, + * we assume that it woke up and we return -EAGAIN. + * Otherwise, we set the task's pi_blocked_on to + * PI_REQUEUE_INPROGRESS, so that if the task is waking up + * it will know that we are in the process of requeuing it. + */ + raw_spin_lock_irq(&task->pi_lock); + if (task->pi_blocked_on) { + raw_spin_unlock_irq(&task->pi_lock); + raw_spin_unlock(&lock->wait_lock); + return -EAGAIN; + } + task->pi_blocked_on = PI_REQUEUE_INPROGRESS; + raw_spin_unlock_irq(&task->pi_lock); +#endif + /* We enforce deadlock detection for futexes */ ret = task_blocks_on_rt_mutex(lock, waiter, task, RT_MUTEX_FULL_CHAINWALK); @@ -1627,7 +2197,7 @@ set_current_state(TASK_INTERRUPTIBLE); - ret = __rt_mutex_slowlock(lock, TASK_INTERRUPTIBLE, to, waiter); + ret = __rt_mutex_slowlock(lock, TASK_INTERRUPTIBLE, to, waiter, NULL); set_current_state(TASK_RUNNING); @@ -1644,3 +2214,89 @@ return ret; } + +static inline int +ww_mutex_deadlock_injection(struct ww_mutex *lock, struct ww_acquire_ctx *ctx) +{ +#ifdef CONFIG_DEBUG_WW_MUTEX_SLOWPATH + unsigned tmp; + + if (ctx->deadlock_inject_countdown-- == 0) { + tmp = ctx->deadlock_inject_interval; + if (tmp > UINT_MAX/4) + tmp = UINT_MAX; + else + tmp = tmp*2 + tmp + tmp/2; + + ctx->deadlock_inject_interval = tmp; + ctx->deadlock_inject_countdown = tmp; + ctx->contending_lock = lock; + + ww_mutex_unlock(lock); + + return -EDEADLK; + } +#endif + + return 0; +} + +#ifdef CONFIG_PREEMPT_RT_FULL +int __sched +__ww_mutex_lock_interruptible(struct ww_mutex *lock, struct ww_acquire_ctx *ww_ctx) +{ + int ret; + + might_sleep(); + + mutex_acquire_nest(&lock->base.dep_map, 0, 0, &ww_ctx->dep_map, _RET_IP_); + ret = rt_mutex_slowlock(&lock->base.lock, TASK_INTERRUPTIBLE, NULL, 0, ww_ctx); + if (ret) + mutex_release(&lock->base.dep_map, 1, _RET_IP_); + else if (!ret && ww_ctx->acquired > 1) + return ww_mutex_deadlock_injection(lock, ww_ctx); + + return ret; +} +EXPORT_SYMBOL_GPL(__ww_mutex_lock_interruptible); + +int __sched +__ww_mutex_lock(struct ww_mutex *lock, struct ww_acquire_ctx *ww_ctx) +{ + int ret; + + might_sleep(); + + mutex_acquire_nest(&lock->base.dep_map, 0, 0, &ww_ctx->dep_map, _RET_IP_); + ret = rt_mutex_slowlock(&lock->base.lock, TASK_UNINTERRUPTIBLE, NULL, 0, ww_ctx); + if (ret) + mutex_release(&lock->base.dep_map, 1, _RET_IP_); + else if (!ret && ww_ctx->acquired > 1) + return ww_mutex_deadlock_injection(lock, ww_ctx); + + return ret; +} +EXPORT_SYMBOL_GPL(__ww_mutex_lock); + +void __sched ww_mutex_unlock(struct ww_mutex *lock) +{ + int nest = !!lock->ctx; + + /* + * The unlocking fastpath is the 0->1 transition from 'locked' + * into 'unlocked' state: + */ + if (nest) { +#ifdef CONFIG_DEBUG_MUTEXES + DEBUG_LOCKS_WARN_ON(!lock->ctx->acquired); +#endif + if (lock->ctx->acquired > 0) + lock->ctx->acquired--; + lock->ctx = NULL; + } + + mutex_release(&lock->base.dep_map, nest, _RET_IP_); + rt_mutex_unlock(&lock->base.lock); +} +EXPORT_SYMBOL(ww_mutex_unlock); +#endif diff -Nur linux-3.18.14.orig/kernel/locking/rtmutex_common.h linux-3.18.14-rt/kernel/locking/rtmutex_common.h --- linux-3.18.14.orig/kernel/locking/rtmutex_common.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/locking/rtmutex_common.h 2015-05-31 15:32:48.769635364 -0500 @@ -49,6 +49,7 @@ struct rb_node pi_tree_entry; struct task_struct *task; struct rt_mutex *lock; + bool savestate; #ifdef CONFIG_DEBUG_RT_MUTEXES unsigned long ip; struct pid *deadlock_task_pid; @@ -119,6 +120,9 @@ /* * PI-futex support (proxy locking functions, etc.): */ +#define PI_WAKEUP_INPROGRESS ((struct rt_mutex_waiter *) 1) +#define PI_REQUEUE_INPROGRESS ((struct rt_mutex_waiter *) 2) + extern struct task_struct *rt_mutex_next_owner(struct rt_mutex *lock); extern void rt_mutex_init_proxy_locked(struct rt_mutex *lock, struct task_struct *proxy_owner); @@ -138,4 +142,14 @@ # include "rtmutex.h" #endif +static inline void +rt_mutex_init_waiter(struct rt_mutex_waiter *waiter, bool savestate) +{ + debug_rt_mutex_init_waiter(waiter); + waiter->task = NULL; + waiter->savestate = savestate; + RB_CLEAR_NODE(&waiter->pi_tree_entry); + RB_CLEAR_NODE(&waiter->tree_entry); +} + #endif diff -Nur linux-3.18.14.orig/kernel/locking/spinlock.c linux-3.18.14-rt/kernel/locking/spinlock.c --- linux-3.18.14.orig/kernel/locking/spinlock.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/locking/spinlock.c 2015-05-31 15:32:48.769635364 -0500 @@ -124,8 +124,11 @@ * __[spin|read|write]_lock_bh() */ BUILD_LOCK_OPS(spin, raw_spinlock); + +#ifndef CONFIG_PREEMPT_RT_FULL BUILD_LOCK_OPS(read, rwlock); BUILD_LOCK_OPS(write, rwlock); +#endif #endif @@ -209,6 +212,8 @@ EXPORT_SYMBOL(_raw_spin_unlock_bh); #endif +#ifndef CONFIG_PREEMPT_RT_FULL + #ifndef CONFIG_INLINE_READ_TRYLOCK int __lockfunc _raw_read_trylock(rwlock_t *lock) { @@ -353,6 +358,8 @@ EXPORT_SYMBOL(_raw_write_unlock_bh); #endif +#endif /* !PREEMPT_RT_FULL */ + #ifdef CONFIG_DEBUG_LOCK_ALLOC void __lockfunc _raw_spin_lock_nested(raw_spinlock_t *lock, int subclass) diff -Nur linux-3.18.14.orig/kernel/locking/spinlock_debug.c linux-3.18.14-rt/kernel/locking/spinlock_debug.c --- linux-3.18.14.orig/kernel/locking/spinlock_debug.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/locking/spinlock_debug.c 2015-05-31 15:32:48.793635364 -0500 @@ -31,6 +31,7 @@ EXPORT_SYMBOL(__raw_spin_lock_init); +#ifndef CONFIG_PREEMPT_RT_FULL void __rwlock_init(rwlock_t *lock, const char *name, struct lock_class_key *key) { @@ -48,6 +49,7 @@ } EXPORT_SYMBOL(__rwlock_init); +#endif static void spin_dump(raw_spinlock_t *lock, const char *msg) { @@ -159,6 +161,7 @@ arch_spin_unlock(&lock->raw_lock); } +#ifndef CONFIG_PREEMPT_RT_FULL static void rwlock_bug(rwlock_t *lock, const char *msg) { if (!debug_locks_off()) @@ -300,3 +303,5 @@ debug_write_unlock(lock); arch_write_unlock(&lock->raw_lock); } + +#endif diff -Nur linux-3.18.14.orig/kernel/panic.c linux-3.18.14-rt/kernel/panic.c --- linux-3.18.14.orig/kernel/panic.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/panic.c 2015-05-31 15:32:48.793635364 -0500 @@ -384,9 +384,11 @@ static int init_oops_id(void) { +#ifndef CONFIG_PREEMPT_RT_FULL if (!oops_id) get_random_bytes(&oops_id, sizeof(oops_id)); else +#endif oops_id++; return 0; diff -Nur linux-3.18.14.orig/kernel/power/hibernate.c linux-3.18.14-rt/kernel/power/hibernate.c --- linux-3.18.14.orig/kernel/power/hibernate.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/power/hibernate.c 2015-05-31 15:32:48.797635364 -0500 @@ -287,6 +287,8 @@ local_irq_disable(); + system_state = SYSTEM_SUSPEND; + error = syscore_suspend(); if (error) { printk(KERN_ERR "PM: Some system devices failed to power down, " @@ -316,6 +318,7 @@ syscore_resume(); Enable_irqs: + system_state = SYSTEM_RUNNING; local_irq_enable(); Enable_cpus: @@ -439,6 +442,7 @@ goto Enable_cpus; local_irq_disable(); + system_state = SYSTEM_SUSPEND; error = syscore_suspend(); if (error) @@ -472,6 +476,7 @@ syscore_resume(); Enable_irqs: + system_state = SYSTEM_RUNNING; local_irq_enable(); Enable_cpus: @@ -557,6 +562,7 @@ goto Platform_finish; local_irq_disable(); + system_state = SYSTEM_SUSPEND; syscore_suspend(); if (pm_wakeup_pending()) { error = -EAGAIN; @@ -569,6 +575,7 @@ Power_up: syscore_resume(); + system_state = SYSTEM_RUNNING; local_irq_enable(); enable_nonboot_cpus(); diff -Nur linux-3.18.14.orig/kernel/power/suspend.c linux-3.18.14-rt/kernel/power/suspend.c --- linux-3.18.14.orig/kernel/power/suspend.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/power/suspend.c 2015-05-31 15:32:48.797635364 -0500 @@ -318,6 +318,8 @@ arch_suspend_disable_irqs(); BUG_ON(!irqs_disabled()); + system_state = SYSTEM_SUSPEND; + error = syscore_suspend(); if (!error) { *wakeup = pm_wakeup_pending(); @@ -332,6 +334,8 @@ syscore_resume(); } + system_state = SYSTEM_RUNNING; + arch_suspend_enable_irqs(); BUG_ON(irqs_disabled()); diff -Nur linux-3.18.14.orig/kernel/printk/printk.c linux-3.18.14-rt/kernel/printk/printk.c --- linux-3.18.14.orig/kernel/printk/printk.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/printk/printk.c 2015-05-31 15:32:48.801635363 -0500 @@ -1165,6 +1165,7 @@ { char *text; int len = 0; + int attempts = 0; text = kmalloc(LOG_LINE_MAX + PREFIX_MAX, GFP_KERNEL); if (!text) @@ -1176,7 +1177,14 @@ u64 seq; u32 idx; enum log_flags prev; - + int num_msg; +try_again: + attempts++; + if (attempts > 10) { + len = -EBUSY; + goto out; + } + num_msg = 0; if (clear_seq < log_first_seq) { /* messages are gone, move to first available one */ clear_seq = log_first_seq; @@ -1197,6 +1205,14 @@ prev = msg->flags; idx = log_next(idx); seq++; + num_msg++; + if (num_msg > 5) { + num_msg = 0; + raw_spin_unlock_irq(&logbuf_lock); + raw_spin_lock_irq(&logbuf_lock); + if (clear_seq < log_first_seq) + goto try_again; + } } /* move first record forward until length fits into the buffer */ @@ -1210,6 +1226,14 @@ prev = msg->flags; idx = log_next(idx); seq++; + num_msg++; + if (num_msg > 5) { + num_msg = 0; + raw_spin_unlock_irq(&logbuf_lock); + raw_spin_lock_irq(&logbuf_lock); + if (clear_seq < log_first_seq) + goto try_again; + } } /* last message fitting into this dump */ @@ -1250,6 +1274,7 @@ clear_seq = log_next_seq; clear_idx = log_next_idx; } +out: raw_spin_unlock_irq(&logbuf_lock); kfree(text); @@ -1407,6 +1432,7 @@ if (!console_drivers) return; + migrate_disable(); for_each_console(con) { if (exclusive_console && con != exclusive_console) continue; @@ -1419,6 +1445,7 @@ continue; con->write(con, text, len); } + migrate_enable(); } /* @@ -1479,6 +1506,15 @@ static int console_trylock_for_printk(void) { unsigned int cpu = smp_processor_id(); +#ifdef CONFIG_PREEMPT_RT_FULL + int lock = !early_boot_irqs_disabled && (preempt_count() == 0) && + !irqs_disabled(); +#else + int lock = 1; +#endif + + if (!lock) + return 0; if (!console_trylock()) return 0; @@ -1613,6 +1649,62 @@ return textlen; } +#ifdef CONFIG_EARLY_PRINTK +struct console *early_console; + +void early_vprintk(const char *fmt, va_list ap) +{ + if (early_console) { + char buf[512]; + int n = vscnprintf(buf, sizeof(buf), fmt, ap); + + early_console->write(early_console, buf, n); + } +} + +asmlinkage void early_printk(const char *fmt, ...) +{ + va_list ap; + + va_start(ap, fmt); + early_vprintk(fmt, ap); + va_end(ap); +} + +/* + * This is independent of any log levels - a global + * kill switch that turns off all of printk. + * + * Used by the NMI watchdog if early-printk is enabled. + */ +static bool __read_mostly printk_killswitch; + +static int __init force_early_printk_setup(char *str) +{ + printk_killswitch = true; + return 0; +} +early_param("force_early_printk", force_early_printk_setup); + +void printk_kill(void) +{ + printk_killswitch = true; +} + +static int forced_early_printk(const char *fmt, va_list ap) +{ + if (!printk_killswitch) + return 0; + early_vprintk(fmt, ap); + return 1; +} +#else +static inline int forced_early_printk(const char *fmt, va_list ap) +{ + return 0; +} +#endif + asmlinkage int vprintk_emit(int facility, int level, const char *dict, size_t dictlen, const char *fmt, va_list args) @@ -1629,6 +1721,13 @@ /* cpu currently holding logbuf_lock in this function */ static volatile unsigned int logbuf_cpu = UINT_MAX; + /* + * Fall back to early_printk if a debugging subsystem has + * killed printk output + */ + if (unlikely(forced_early_printk(fmt, args))) + return 1; + if (level == SCHED_MESSAGE_LOGLEVEL) { level = -1; in_sched = true; @@ -1769,8 +1868,7 @@ * console_sem which would prevent anyone from printing to * console */ - preempt_disable(); - + migrate_disable(); /* * Try to acquire and then immediately release the console * semaphore. The release will print out buffers and wake up @@ -1778,7 +1876,7 @@ */ if (console_trylock_for_printk()) console_unlock(); - preempt_enable(); + migrate_enable(); lockdep_on(); } @@ -1878,29 +1976,6 @@ #endif /* CONFIG_PRINTK */ -#ifdef CONFIG_EARLY_PRINTK -struct console *early_console; - -void early_vprintk(const char *fmt, va_list ap) -{ - if (early_console) { - char buf[512]; - int n = vscnprintf(buf, sizeof(buf), fmt, ap); - - early_console->write(early_console, buf, n); - } -} - -asmlinkage __visible void early_printk(const char *fmt, ...) -{ - va_list ap; - - va_start(ap, fmt); - early_vprintk(fmt, ap); - va_end(ap); -} -#endif - static int __add_preferred_console(char *name, int idx, char *options, char *brl_options) { @@ -2140,11 +2215,16 @@ goto out; len = cont_print_text(text, size); +#ifndef CONFIG_PREEMPT_RT_FULL raw_spin_unlock(&logbuf_lock); stop_critical_timings(); call_console_drivers(cont.level, text, len); start_critical_timings(); local_irq_restore(flags); +#else + raw_spin_unlock_irqrestore(&logbuf_lock, flags); + call_console_drivers(cont.level, text, len); +#endif return; out: raw_spin_unlock_irqrestore(&logbuf_lock, flags); @@ -2232,12 +2312,17 @@ console_idx = log_next(console_idx); console_seq++; console_prev = msg->flags; +#ifdef CONFIG_PREEMPT_RT_FULL + raw_spin_unlock_irqrestore(&logbuf_lock, flags); + call_console_drivers(level, text, len); +#else raw_spin_unlock(&logbuf_lock); stop_critical_timings(); /* don't trace print latency */ call_console_drivers(level, text, len); start_critical_timings(); local_irq_restore(flags); +#endif } console_locked = 0; diff -Nur linux-3.18.14.orig/kernel/ptrace.c linux-3.18.14-rt/kernel/ptrace.c --- linux-3.18.14.orig/kernel/ptrace.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/ptrace.c 2015-05-31 15:32:48.801635363 -0500 @@ -129,7 +129,12 @@ spin_lock_irq(&task->sighand->siglock); if (task_is_traced(task) && !__fatal_signal_pending(task)) { - task->state = __TASK_TRACED; + raw_spin_lock_irq(&task->pi_lock); + if (task->state & __TASK_TRACED) + task->state = __TASK_TRACED; + else + task->saved_state = __TASK_TRACED; + raw_spin_unlock_irq(&task->pi_lock); ret = true; } spin_unlock_irq(&task->sighand->siglock); diff -Nur linux-3.18.14.orig/kernel/rcu/tiny.c linux-3.18.14-rt/kernel/rcu/tiny.c --- linux-3.18.14.orig/kernel/rcu/tiny.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/rcu/tiny.c 2015-05-31 15:32:48.801635363 -0500 @@ -370,6 +370,7 @@ } EXPORT_SYMBOL_GPL(call_rcu_sched); +#ifndef CONFIG_PREEMPT_RT_FULL /* * Post an RCU bottom-half callback to be invoked after any subsequent * quiescent state. @@ -379,6 +380,7 @@ __call_rcu(head, func, &rcu_bh_ctrlblk); } EXPORT_SYMBOL_GPL(call_rcu_bh); +#endif void rcu_init(void) { diff -Nur linux-3.18.14.orig/kernel/rcu/tree.c linux-3.18.14-rt/kernel/rcu/tree.c --- linux-3.18.14.orig/kernel/rcu/tree.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/rcu/tree.c 2015-05-31 15:32:48.805635363 -0500 @@ -56,6 +56,11 @@ #include #include #include +#include +#include +#include +#include +#include "../time/tick-internal.h" #include "tree.h" #include "rcu.h" @@ -152,8 +157,6 @@ */ static int rcu_scheduler_fully_active __read_mostly; -#ifdef CONFIG_RCU_BOOST - /* * Control variables for per-CPU and per-rcu_node kthreads. These * handle all flavors of RCU. @@ -163,8 +166,6 @@ DEFINE_PER_CPU(unsigned int, rcu_cpu_kthread_loops); DEFINE_PER_CPU(char, rcu_cpu_has_work); -#endif /* #ifdef CONFIG_RCU_BOOST */ - static void rcu_boost_kthread_setaffinity(struct rcu_node *rnp, int outgoingcpu); static void invoke_rcu_core(void); static void invoke_rcu_callbacks(struct rcu_state *rsp, struct rcu_data *rdp); @@ -207,6 +208,19 @@ } } +#ifdef CONFIG_PREEMPT_RT_FULL +static void rcu_preempt_qs(void); + +void rcu_bh_qs(void) +{ + unsigned long flags; + + /* Callers to this function, rcu_preempt_qs(), must disable irqs. */ + local_irq_save(flags); + rcu_preempt_qs(); + local_irq_restore(flags); +} +#else void rcu_bh_qs(void) { if (!__this_cpu_read(rcu_bh_data.passed_quiesce)) { @@ -216,6 +230,7 @@ __this_cpu_write(rcu_bh_data.passed_quiesce, 1); } } +#endif static DEFINE_PER_CPU(int, rcu_sched_qs_mask); @@ -336,6 +351,7 @@ } EXPORT_SYMBOL_GPL(rcu_batches_completed_sched); +#ifndef CONFIG_PREEMPT_RT_FULL /* * Return the number of RCU BH batches processed thus far for debug & stats. */ @@ -363,6 +379,13 @@ } EXPORT_SYMBOL_GPL(rcu_bh_force_quiescent_state); +#else +void rcu_force_quiescent_state(void) +{ +} +EXPORT_SYMBOL_GPL(rcu_force_quiescent_state); +#endif + /* * Show the state of the grace-period kthreads. */ @@ -1411,7 +1434,7 @@ !ACCESS_ONCE(rsp->gp_flags) || !rsp->gp_kthread) return; - wake_up(&rsp->gp_wq); + swait_wake(&rsp->gp_wq); } /* @@ -1793,7 +1816,7 @@ ACCESS_ONCE(rsp->gpnum), TPS("reqwait")); rsp->gp_state = RCU_GP_WAIT_GPS; - wait_event_interruptible(rsp->gp_wq, + swait_event_interruptible(rsp->gp_wq, ACCESS_ONCE(rsp->gp_flags) & RCU_GP_FLAG_INIT); /* Locking provides needed memory barrier. */ @@ -1821,7 +1844,7 @@ ACCESS_ONCE(rsp->gpnum), TPS("fqswait")); rsp->gp_state = RCU_GP_WAIT_FQS; - ret = wait_event_interruptible_timeout(rsp->gp_wq, + ret = swait_event_interruptible_timeout(rsp->gp_wq, ((gf = ACCESS_ONCE(rsp->gp_flags)) & RCU_GP_FLAG_FQS) || (!ACCESS_ONCE(rnp->qsmask) && @@ -2565,16 +2588,14 @@ /* * Do RCU core processing for the current CPU. */ -static void rcu_process_callbacks(struct softirq_action *unused) +static void rcu_process_callbacks(void) { struct rcu_state *rsp; if (cpu_is_offline(smp_processor_id())) return; - trace_rcu_utilization(TPS("Start RCU core")); for_each_rcu_flavor(rsp) __rcu_process_callbacks(rsp); - trace_rcu_utilization(TPS("End RCU core")); } /* @@ -2588,18 +2609,105 @@ { if (unlikely(!ACCESS_ONCE(rcu_scheduler_fully_active))) return; - if (likely(!rsp->boost)) { - rcu_do_batch(rsp, rdp); + rcu_do_batch(rsp, rdp); +} + +static void rcu_wake_cond(struct task_struct *t, int status) +{ + /* + * If the thread is yielding, only wake it when this + * is invoked from idle + */ + if (t && (status != RCU_KTHREAD_YIELDING || is_idle_task(current))) + wake_up_process(t); +} + +/* + * Wake up this CPU's rcuc kthread to do RCU core processing. + */ +static void invoke_rcu_core(void) +{ + unsigned long flags; + struct task_struct *t; + + if (!cpu_online(smp_processor_id())) return; + local_irq_save(flags); + __this_cpu_write(rcu_cpu_has_work, 1); + t = __this_cpu_read(rcu_cpu_kthread_task); + if (t != NULL && current != t) + rcu_wake_cond(t, __this_cpu_read(rcu_cpu_kthread_status)); + local_irq_restore(flags); +} + +static void rcu_cpu_kthread_park(unsigned int cpu) +{ + per_cpu(rcu_cpu_kthread_status, cpu) = RCU_KTHREAD_OFFCPU; +} + +static int rcu_cpu_kthread_should_run(unsigned int cpu) +{ + return __this_cpu_read(rcu_cpu_has_work); +} + +/* + * Per-CPU kernel thread that invokes RCU callbacks. This replaces the + * RCU softirq used in flavors and configurations of RCU that do not + * support RCU priority boosting. + */ +static void rcu_cpu_kthread(unsigned int cpu) +{ + unsigned int *statusp = &__get_cpu_var(rcu_cpu_kthread_status); + char work, *workp = &__get_cpu_var(rcu_cpu_has_work); + int spincnt; + + for (spincnt = 0; spincnt < 10; spincnt++) { + trace_rcu_utilization(TPS("Start CPU kthread@rcu_wait")); + local_bh_disable(); + *statusp = RCU_KTHREAD_RUNNING; + this_cpu_inc(rcu_cpu_kthread_loops); + local_irq_disable(); + work = *workp; + *workp = 0; + local_irq_enable(); + if (work) + rcu_process_callbacks(); + local_bh_enable(); + if (*workp == 0) { + trace_rcu_utilization(TPS("End CPU kthread@rcu_wait")); + *statusp = RCU_KTHREAD_WAITING; + return; + } } - invoke_rcu_callbacks_kthread(); + *statusp = RCU_KTHREAD_YIELDING; + trace_rcu_utilization(TPS("Start CPU kthread@rcu_yield")); + schedule_timeout_interruptible(2); + trace_rcu_utilization(TPS("End CPU kthread@rcu_yield")); + *statusp = RCU_KTHREAD_WAITING; } -static void invoke_rcu_core(void) +static struct smp_hotplug_thread rcu_cpu_thread_spec = { + .store = &rcu_cpu_kthread_task, + .thread_should_run = rcu_cpu_kthread_should_run, + .thread_fn = rcu_cpu_kthread, + .thread_comm = "rcuc/%u", + .setup = rcu_cpu_kthread_setup, + .park = rcu_cpu_kthread_park, +}; + +/* + * Spawn per-CPU RCU core processing kthreads. + */ +static int __init rcu_spawn_core_kthreads(void) { - if (cpu_online(smp_processor_id())) - raise_softirq(RCU_SOFTIRQ); + int cpu; + + for_each_possible_cpu(cpu) + per_cpu(rcu_cpu_has_work, cpu) = 0; + BUG_ON(smpboot_register_percpu_thread(&rcu_cpu_thread_spec)); + return 0; } +early_initcall(rcu_spawn_core_kthreads); /* * Handle any core-RCU processing required by a call_rcu() invocation. @@ -2734,6 +2842,7 @@ } EXPORT_SYMBOL_GPL(call_rcu_sched); +#ifndef CONFIG_PREEMPT_RT_FULL /* * Queue an RCU callback for invocation after a quicker grace period. */ @@ -2742,6 +2851,7 @@ __call_rcu(head, func, &rcu_bh_state, -1, 0); } EXPORT_SYMBOL_GPL(call_rcu_bh); +#endif /* * Queue an RCU callback for lazy invocation after a grace period. @@ -2833,6 +2943,7 @@ } EXPORT_SYMBOL_GPL(synchronize_sched); +#ifndef CONFIG_PREEMPT_RT_FULL /** * synchronize_rcu_bh - wait until an rcu_bh grace period has elapsed. * @@ -2859,6 +2970,7 @@ wait_rcu_gp(call_rcu_bh); } EXPORT_SYMBOL_GPL(synchronize_rcu_bh); +#endif /** * get_state_synchronize_rcu - Snapshot current RCU state @@ -3341,6 +3453,7 @@ mutex_unlock(&rsp->barrier_mutex); } +#ifndef CONFIG_PREEMPT_RT_FULL /** * rcu_barrier_bh - Wait until all in-flight call_rcu_bh() callbacks complete. */ @@ -3349,6 +3462,7 @@ _rcu_barrier(&rcu_bh_state); } EXPORT_SYMBOL_GPL(rcu_barrier_bh); +#endif /** * rcu_barrier_sched - Wait for in-flight call_rcu_sched() callbacks. @@ -3658,7 +3772,7 @@ } rsp->rda = rda; - init_waitqueue_head(&rsp->gp_wq); + init_swait_head(&rsp->gp_wq); rnp = rsp->level[rcu_num_lvls - 1]; for_each_possible_cpu(i) { while (i > rnp->grphi) @@ -3755,7 +3869,6 @@ rcu_init_one(&rcu_bh_state, &rcu_bh_data); rcu_init_one(&rcu_sched_state, &rcu_sched_data); __rcu_init_preempt(); - open_softirq(RCU_SOFTIRQ, rcu_process_callbacks); /* * We don't need protection against CPU-hotplug here because diff -Nur linux-3.18.14.orig/kernel/rcu/tree.h linux-3.18.14-rt/kernel/rcu/tree.h --- linux-3.18.14.orig/kernel/rcu/tree.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/rcu/tree.h 2015-05-31 15:32:48.809635364 -0500 @@ -28,6 +28,7 @@ #include #include #include +#include /* * Define shape of hierarchy based on NR_CPUS, CONFIG_RCU_FANOUT, and @@ -172,11 +173,6 @@ /* queued on this rcu_node structure that */ /* are blocking the current grace period, */ /* there can be no such task. */ - struct completion boost_completion; - /* Used to ensure that the rt_mutex used */ - /* to carry out the boosting is fully */ - /* released with no future boostee accesses */ - /* before that rt_mutex is re-initialized. */ struct rt_mutex boost_mtx; /* Used only for the priority-boosting */ /* side effect, not as a lock. */ @@ -208,7 +204,7 @@ /* This can happen due to race conditions. */ #endif /* #ifdef CONFIG_RCU_BOOST */ #ifdef CONFIG_RCU_NOCB_CPU - wait_queue_head_t nocb_gp_wq[2]; + struct swait_head nocb_gp_wq[2]; /* Place for rcu_nocb_kthread() to wait GP. */ #endif /* #ifdef CONFIG_RCU_NOCB_CPU */ int need_future_gp[2]; @@ -348,7 +344,7 @@ atomic_long_t nocb_follower_count_lazy; /* (approximate). */ int nocb_p_count; /* # CBs being invoked by kthread */ int nocb_p_count_lazy; /* (approximate). */ - wait_queue_head_t nocb_wq; /* For nocb kthreads to sleep on. */ + struct swait_head nocb_wq; /* For nocb kthreads to sleep on. */ struct task_struct *nocb_kthread; int nocb_defer_wakeup; /* Defer wakeup of nocb_kthread. */ @@ -439,7 +435,7 @@ unsigned long gpnum; /* Current gp number. */ unsigned long completed; /* # of last completed gp. */ struct task_struct *gp_kthread; /* Task for grace periods. */ - wait_queue_head_t gp_wq; /* Where GP task waits. */ + struct swait_head gp_wq; /* Where GP task waits. */ short gp_flags; /* Commands for GP task. */ short gp_state; /* GP kthread sleep state. */ @@ -570,10 +566,9 @@ static void __init __rcu_init_preempt(void); static void rcu_initiate_boost(struct rcu_node *rnp, unsigned long flags); static void rcu_preempt_boost_start_gp(struct rcu_node *rnp); -static void invoke_rcu_callbacks_kthread(void); static bool rcu_is_callbacks_kthread(void); +static void rcu_cpu_kthread_setup(unsigned int cpu); #ifdef CONFIG_RCU_BOOST -static void rcu_preempt_do_callbacks(void); static int rcu_spawn_one_boost_kthread(struct rcu_state *rsp, struct rcu_node *rnp); #endif /* #ifdef CONFIG_RCU_BOOST */ diff -Nur linux-3.18.14.orig/kernel/rcu/tree_plugin.h linux-3.18.14-rt/kernel/rcu/tree_plugin.h --- linux-3.18.14.orig/kernel/rcu/tree_plugin.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/rcu/tree_plugin.h 2015-05-31 15:32:48.829635363 -0500 @@ -24,12 +24,6 @@ * Paul E. McKenney */ -#include -#include -#include -#include -#include "../time/tick-internal.h" - #define RCU_KTHREAD_PRIO 1 #ifdef CONFIG_RCU_BOOST @@ -335,7 +329,7 @@ } /* Hardware IRQ handlers cannot block, complain if they get here. */ - if (WARN_ON_ONCE(in_irq() || in_serving_softirq())) { + if (WARN_ON_ONCE(preempt_count() & (HARDIRQ_MASK | SOFTIRQ_OFFSET))) { local_irq_restore(flags); return; } @@ -398,10 +392,8 @@ #ifdef CONFIG_RCU_BOOST /* Unboost if we were boosted. */ - if (drop_boost_mutex) { + if (drop_boost_mutex) rt_mutex_unlock(&rnp->boost_mtx); - complete(&rnp->boost_completion); - } #endif /* #ifdef CONFIG_RCU_BOOST */ /* @@ -635,15 +627,6 @@ t->rcu_read_unlock_special.b.need_qs = true; } -#ifdef CONFIG_RCU_BOOST - -static void rcu_preempt_do_callbacks(void) -{ - rcu_do_batch(&rcu_preempt_state, this_cpu_ptr(&rcu_preempt_data)); -} - -#endif /* #ifdef CONFIG_RCU_BOOST */ - /* * Queue a preemptible-RCU callback for invocation after a grace period. */ @@ -1072,6 +1055,19 @@ #endif /* #else #ifdef CONFIG_TREE_PREEMPT_RCU */ +/* + * If boosting, set rcuc kthreads to realtime priority. + */ +static void rcu_cpu_kthread_setup(unsigned int cpu) +{ +#ifdef CONFIG_RCU_BOOST + struct sched_param sp; + + sp.sched_priority = RCU_KTHREAD_PRIO; + sched_setscheduler_nocheck(current, SCHED_FIFO, &sp); +#endif /* #ifdef CONFIG_RCU_BOOST */ +} + #ifdef CONFIG_RCU_BOOST #include "../locking/rtmutex_common.h" @@ -1103,16 +1099,6 @@ #endif /* #else #ifdef CONFIG_RCU_TRACE */ -static void rcu_wake_cond(struct task_struct *t, int status) -{ - /* - * If the thread is yielding, only wake it when this - * is invoked from idle - */ - if (status != RCU_KTHREAD_YIELDING || is_idle_task(current)) - wake_up_process(t); -} - /* * Carry out RCU priority boosting on the task indicated by ->exp_tasks * or ->boost_tasks, advancing the pointer to the next task in the @@ -1175,15 +1161,11 @@ */ t = container_of(tb, struct task_struct, rcu_node_entry); rt_mutex_init_proxy_locked(&rnp->boost_mtx, t); - init_completion(&rnp->boost_completion); raw_spin_unlock_irqrestore(&rnp->lock, flags); /* Lock only for side effect: boosts task t's priority. */ rt_mutex_lock(&rnp->boost_mtx); rt_mutex_unlock(&rnp->boost_mtx); /* Then keep lockdep happy. */ - /* Wait for boostee to be done w/boost_mtx before reinitializing. */ - wait_for_completion(&rnp->boost_completion); - return ACCESS_ONCE(rnp->exp_tasks) != NULL || ACCESS_ONCE(rnp->boost_tasks) != NULL; } @@ -1261,23 +1243,6 @@ } /* - * Wake up the per-CPU kthread to invoke RCU callbacks. - */ -static void invoke_rcu_callbacks_kthread(void) -{ - unsigned long flags; - - local_irq_save(flags); - __this_cpu_write(rcu_cpu_has_work, 1); - if (__this_cpu_read(rcu_cpu_kthread_task) != NULL && - current != __this_cpu_read(rcu_cpu_kthread_task)) { - rcu_wake_cond(__this_cpu_read(rcu_cpu_kthread_task), - __this_cpu_read(rcu_cpu_kthread_status)); - } - local_irq_restore(flags); -} - -/* * Is the current CPU running the RCU-callbacks kthread? * Caller must have preemption disabled. */ @@ -1332,67 +1297,6 @@ return 0; } -static void rcu_kthread_do_work(void) -{ - rcu_do_batch(&rcu_sched_state, this_cpu_ptr(&rcu_sched_data)); - rcu_do_batch(&rcu_bh_state, this_cpu_ptr(&rcu_bh_data)); - rcu_preempt_do_callbacks(); -} - -static void rcu_cpu_kthread_setup(unsigned int cpu) -{ - struct sched_param sp; - - sp.sched_priority = RCU_KTHREAD_PRIO; - sched_setscheduler_nocheck(current, SCHED_FIFO, &sp); -} - -static void rcu_cpu_kthread_park(unsigned int cpu) -{ - per_cpu(rcu_cpu_kthread_status, cpu) = RCU_KTHREAD_OFFCPU; -} - -static int rcu_cpu_kthread_should_run(unsigned int cpu) -{ - return __this_cpu_read(rcu_cpu_has_work); -} - -/* - * Per-CPU kernel thread that invokes RCU callbacks. This replaces the - * RCU softirq used in flavors and configurations of RCU that do not - * support RCU priority boosting. - */ -static void rcu_cpu_kthread(unsigned int cpu) -{ - unsigned int *statusp = this_cpu_ptr(&rcu_cpu_kthread_status); - char work, *workp = this_cpu_ptr(&rcu_cpu_has_work); - int spincnt; - - for (spincnt = 0; spincnt < 10; spincnt++) { - trace_rcu_utilization(TPS("Start CPU kthread@rcu_wait")); - local_bh_disable(); - *statusp = RCU_KTHREAD_RUNNING; - this_cpu_inc(rcu_cpu_kthread_loops); - local_irq_disable(); - work = *workp; - *workp = 0; - local_irq_enable(); - if (work) - rcu_kthread_do_work(); - local_bh_enable(); - if (*workp == 0) { - trace_rcu_utilization(TPS("End CPU kthread@rcu_wait")); - *statusp = RCU_KTHREAD_WAITING; - return; - } - } - *statusp = RCU_KTHREAD_YIELDING; - trace_rcu_utilization(TPS("Start CPU kthread@rcu_yield")); - schedule_timeout_interruptible(2); - trace_rcu_utilization(TPS("End CPU kthread@rcu_yield")); - *statusp = RCU_KTHREAD_WAITING; -} - /* * Set the per-rcu_node kthread's affinity to cover all CPUs that are * served by the rcu_node in question. The CPU hotplug lock is still @@ -1426,26 +1330,13 @@ free_cpumask_var(cm); } -static struct smp_hotplug_thread rcu_cpu_thread_spec = { - .store = &rcu_cpu_kthread_task, - .thread_should_run = rcu_cpu_kthread_should_run, - .thread_fn = rcu_cpu_kthread, - .thread_comm = "rcuc/%u", - .setup = rcu_cpu_kthread_setup, - .park = rcu_cpu_kthread_park, -}; - /* * Spawn boost kthreads -- called as soon as the scheduler is running. */ static void __init rcu_spawn_boost_kthreads(void) { struct rcu_node *rnp; - int cpu; - for_each_possible_cpu(cpu) - per_cpu(rcu_cpu_has_work, cpu) = 0; - BUG_ON(smpboot_register_percpu_thread(&rcu_cpu_thread_spec)); rnp = rcu_get_root(rcu_state_p); (void)rcu_spawn_one_boost_kthread(rcu_state_p, rnp); if (NUM_RCU_NODES > 1) { @@ -1472,11 +1363,6 @@ raw_spin_unlock_irqrestore(&rnp->lock, flags); } -static void invoke_rcu_callbacks_kthread(void) -{ - WARN_ON_ONCE(1); -} - static bool rcu_is_callbacks_kthread(void) { return false; @@ -1500,7 +1386,7 @@ #endif /* #else #ifdef CONFIG_RCU_BOOST */ -#if !defined(CONFIG_RCU_FAST_NO_HZ) +#if !defined(CONFIG_RCU_FAST_NO_HZ) || defined(CONFIG_PREEMPT_RT_FULL) /* * Check to see if any future RCU-related work will need to be done @@ -1518,7 +1404,9 @@ return rcu_cpu_has_callbacks(cpu, NULL); } #endif /* #ifndef CONFIG_RCU_NOCB_CPU_ALL */ +#endif /* !defined(CONFIG_RCU_FAST_NO_HZ) || defined(CONFIG_PREEMPT_RT_FULL) */ +#if !defined(CONFIG_RCU_FAST_NO_HZ) /* * Because we do not have RCU_FAST_NO_HZ, don't bother cleaning up * after it. @@ -1615,6 +1503,8 @@ return cbs_ready; } +#ifndef CONFIG_PREEMPT_RT_FULL + /* * Allow the CPU to enter dyntick-idle mode unless it has callbacks ready * to invoke. If the CPU has callbacks, try to advance them. Tell the @@ -1655,7 +1545,7 @@ return 0; } #endif /* #ifndef CONFIG_RCU_NOCB_CPU_ALL */ - +#endif /* #ifndef CONFIG_PREEMPT_RT_FULL */ /* * Prepare a CPU for idle from an RCU perspective. The first major task * is to sense whether nohz mode has been enabled or disabled via sysfs. @@ -2001,7 +1891,7 @@ */ static void rcu_nocb_gp_cleanup(struct rcu_state *rsp, struct rcu_node *rnp) { - wake_up_all(&rnp->nocb_gp_wq[rnp->completed & 0x1]); + swait_wake_all(&rnp->nocb_gp_wq[rnp->completed & 0x1]); } /* @@ -2019,8 +1909,8 @@ static void rcu_init_one_nocb(struct rcu_node *rnp) { - init_waitqueue_head(&rnp->nocb_gp_wq[0]); - init_waitqueue_head(&rnp->nocb_gp_wq[1]); + init_swait_head(&rnp->nocb_gp_wq[0]); + init_swait_head(&rnp->nocb_gp_wq[1]); } #ifndef CONFIG_RCU_NOCB_CPU_ALL @@ -2045,7 +1935,7 @@ if (ACCESS_ONCE(rdp_leader->nocb_leader_sleep) || force) { /* Prior smp_mb__after_atomic() orders against prior enqueue. */ ACCESS_ONCE(rdp_leader->nocb_leader_sleep) = false; - wake_up(&rdp_leader->nocb_wq); + swait_wake(&rdp_leader->nocb_wq); } } @@ -2238,7 +2128,7 @@ */ trace_rcu_future_gp(rnp, rdp, c, TPS("StartWait")); for (;;) { - wait_event_interruptible( + swait_event_interruptible( rnp->nocb_gp_wq[c & 0x1], (d = ULONG_CMP_GE(ACCESS_ONCE(rnp->completed), c))); if (likely(d)) @@ -2266,7 +2156,7 @@ /* Wait for callbacks to appear. */ if (!rcu_nocb_poll) { trace_rcu_nocb_wake(my_rdp->rsp->name, my_rdp->cpu, "Sleep"); - wait_event_interruptible(my_rdp->nocb_wq, + swait_event_interruptible(my_rdp->nocb_wq, !ACCESS_ONCE(my_rdp->nocb_leader_sleep)); /* Memory barrier handled by smp_mb() calls below and repoll. */ } else if (firsttime) { @@ -2347,7 +2237,7 @@ * List was empty, wake up the follower. * Memory barriers supplied by atomic_long_add(). */ - wake_up(&rdp->nocb_wq); + swait_wake(&rdp->nocb_wq); } } @@ -2368,7 +2258,7 @@ if (!rcu_nocb_poll) { trace_rcu_nocb_wake(rdp->rsp->name, rdp->cpu, "FollowerSleep"); - wait_event_interruptible(rdp->nocb_wq, + swait_event_interruptible(rdp->nocb_wq, ACCESS_ONCE(rdp->nocb_follower_head)); } else if (firsttime) { /* Don't drown trace log with "Poll"! */ @@ -2539,7 +2429,7 @@ static void __init rcu_boot_init_nocb_percpu_data(struct rcu_data *rdp) { rdp->nocb_tail = &rdp->nocb_head; - init_waitqueue_head(&rdp->nocb_wq); + init_swait_head(&rdp->nocb_wq); rdp->nocb_follower_tail = &rdp->nocb_follower_head; } diff -Nur linux-3.18.14.orig/kernel/rcu/update.c linux-3.18.14-rt/kernel/rcu/update.c --- linux-3.18.14.orig/kernel/rcu/update.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/rcu/update.c 2015-05-31 15:32:48.829635363 -0500 @@ -170,6 +170,7 @@ } EXPORT_SYMBOL_GPL(rcu_read_lock_held); +#ifndef CONFIG_PREEMPT_RT_FULL /** * rcu_read_lock_bh_held() - might we be in RCU-bh read-side critical section? * @@ -196,6 +197,7 @@ return in_softirq() || irqs_disabled(); } EXPORT_SYMBOL_GPL(rcu_read_lock_bh_held); +#endif #endif /* #ifdef CONFIG_DEBUG_LOCK_ALLOC */ diff -Nur linux-3.18.14.orig/kernel/relay.c linux-3.18.14-rt/kernel/relay.c --- linux-3.18.14.orig/kernel/relay.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/relay.c 2015-05-31 15:32:48.829635363 -0500 @@ -339,6 +339,10 @@ { struct rchan_buf *buf = (struct rchan_buf *)data; wake_up_interruptible(&buf->read_wait); + /* + * Stupid polling for now: + */ + mod_timer(&buf->timer, jiffies + 1); } /** @@ -356,6 +360,7 @@ init_waitqueue_head(&buf->read_wait); kref_init(&buf->kref); setup_timer(&buf->timer, wakeup_readers, (unsigned long)buf); + mod_timer(&buf->timer, jiffies + 1); } else del_timer_sync(&buf->timer); @@ -739,15 +744,6 @@ else buf->early_bytes += buf->chan->subbuf_size - buf->padding[old_subbuf]; - smp_mb(); - if (waitqueue_active(&buf->read_wait)) - /* - * Calling wake_up_interruptible() from here - * will deadlock if we happen to be logging - * from the scheduler (trying to re-grab - * rq->lock), so defer it. - */ - mod_timer(&buf->timer, jiffies + 1); } old = buf->data; diff -Nur linux-3.18.14.orig/kernel/res_counter.c linux-3.18.14-rt/kernel/res_counter.c --- linux-3.18.14.orig/kernel/res_counter.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/res_counter.c 2015-05-31 15:32:48.845635363 -0500 @@ -59,7 +59,7 @@ r = ret = 0; *limit_fail_at = NULL; - local_irq_save(flags); + local_irq_save_nort(flags); for (c = counter; c != NULL; c = c->parent) { spin_lock(&c->lock); r = res_counter_charge_locked(c, val, force); @@ -79,7 +79,7 @@ spin_unlock(&u->lock); } } - local_irq_restore(flags); + local_irq_restore_nort(flags); return ret; } @@ -104,7 +104,7 @@ struct res_counter *c; u64 ret = 0; - local_irq_save(flags); + local_irq_save_nort(flags); for (c = counter; c != top; c = c->parent) { u64 r; spin_lock(&c->lock); @@ -113,7 +113,7 @@ ret = r; spin_unlock(&c->lock); } - local_irq_restore(flags); + local_irq_restore_nort(flags); return ret; } diff -Nur linux-3.18.14.orig/kernel/sched/completion.c linux-3.18.14-rt/kernel/sched/completion.c --- linux-3.18.14.orig/kernel/sched/completion.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/sched/completion.c 2015-05-31 15:32:48.889635363 -0500 @@ -30,10 +30,10 @@ { unsigned long flags; - spin_lock_irqsave(&x->wait.lock, flags); + raw_spin_lock_irqsave(&x->wait.lock, flags); x->done++; - __wake_up_locked(&x->wait, TASK_NORMAL, 1); - spin_unlock_irqrestore(&x->wait.lock, flags); + __swait_wake_locked(&x->wait, TASK_NORMAL, 1); + raw_spin_unlock_irqrestore(&x->wait.lock, flags); } EXPORT_SYMBOL(complete); @@ -50,10 +50,10 @@ { unsigned long flags; - spin_lock_irqsave(&x->wait.lock, flags); + raw_spin_lock_irqsave(&x->wait.lock, flags); x->done += UINT_MAX/2; - __wake_up_locked(&x->wait, TASK_NORMAL, 0); - spin_unlock_irqrestore(&x->wait.lock, flags); + __swait_wake_locked(&x->wait, TASK_NORMAL, 0); + raw_spin_unlock_irqrestore(&x->wait.lock, flags); } EXPORT_SYMBOL(complete_all); @@ -62,20 +62,20 @@ long (*action)(long), long timeout, int state) { if (!x->done) { - DECLARE_WAITQUEUE(wait, current); + DEFINE_SWAITER(wait); - __add_wait_queue_tail_exclusive(&x->wait, &wait); + swait_prepare_locked(&x->wait, &wait); do { if (signal_pending_state(state, current)) { timeout = -ERESTARTSYS; break; } __set_current_state(state); - spin_unlock_irq(&x->wait.lock); + raw_spin_unlock_irq(&x->wait.lock); timeout = action(timeout); - spin_lock_irq(&x->wait.lock); + raw_spin_lock_irq(&x->wait.lock); } while (!x->done && timeout); - __remove_wait_queue(&x->wait, &wait); + swait_finish_locked(&x->wait, &wait); if (!x->done) return timeout; } @@ -89,9 +89,9 @@ { might_sleep(); - spin_lock_irq(&x->wait.lock); + raw_spin_lock_irq(&x->wait.lock); timeout = do_wait_for_common(x, action, timeout, state); - spin_unlock_irq(&x->wait.lock); + raw_spin_unlock_irq(&x->wait.lock); return timeout; } @@ -267,12 +267,12 @@ unsigned long flags; int ret = 1; - spin_lock_irqsave(&x->wait.lock, flags); + raw_spin_lock_irqsave(&x->wait.lock, flags); if (!x->done) ret = 0; else x->done--; - spin_unlock_irqrestore(&x->wait.lock, flags); + raw_spin_unlock_irqrestore(&x->wait.lock, flags); return ret; } EXPORT_SYMBOL(try_wait_for_completion); @@ -290,10 +290,10 @@ unsigned long flags; int ret = 1; - spin_lock_irqsave(&x->wait.lock, flags); + raw_spin_lock_irqsave(&x->wait.lock, flags); if (!x->done) ret = 0; - spin_unlock_irqrestore(&x->wait.lock, flags); + raw_spin_unlock_irqrestore(&x->wait.lock, flags); return ret; } EXPORT_SYMBOL(completion_done); diff -Nur linux-3.18.14.orig/kernel/sched/core.c linux-3.18.14-rt/kernel/sched/core.c --- linux-3.18.14.orig/kernel/sched/core.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/sched/core.c 2015-05-31 15:32:48.893635363 -0500 @@ -280,7 +280,11 @@ * Number of tasks to iterate in a single balance run. * Limited because this is done with IRQs disabled. */ +#ifndef CONFIG_PREEMPT_RT_FULL const_debug unsigned int sysctl_sched_nr_migrate = 32; +#else +const_debug unsigned int sysctl_sched_nr_migrate = 8; +#endif /* * period over which we average the RT time consumption, measured @@ -516,6 +520,7 @@ hrtimer_init(&rq->hrtick_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); rq->hrtick_timer.function = hrtick; + rq->hrtick_timer.irqsafe = 1; } #else /* CONFIG_SCHED_HRTICK */ static inline void hrtick_clear(struct rq *rq) @@ -627,6 +632,38 @@ trace_sched_wake_idle_without_ipi(cpu); } +#ifdef CONFIG_PREEMPT_LAZY +void resched_curr_lazy(struct rq *rq) +{ + struct task_struct *curr = rq->curr; + int cpu; + + if (!sched_feat(PREEMPT_LAZY)) { + resched_curr(rq); + return; + } + + lockdep_assert_held(&rq->lock); + + if (test_tsk_need_resched(curr)) + return; + + if (test_tsk_need_resched_lazy(curr)) + return; + + set_tsk_need_resched_lazy(curr); + + cpu = cpu_of(rq); + if (cpu == smp_processor_id()) + return; + + /* NEED_RESCHED_LAZY must be visible before we test polling */ + smp_mb(); + if (!tsk_is_polling(curr)) + smp_send_reschedule(cpu); +} +#endif + void resched_cpu(int cpu) { struct rq *rq = cpu_rq(cpu); @@ -650,12 +687,14 @@ */ int get_nohz_timer_target(int pinned) { - int cpu = smp_processor_id(); + int cpu; int i; struct sched_domain *sd; + preempt_disable_rt(); + cpu = smp_processor_id(); if (pinned || !get_sysctl_timer_migration() || !idle_cpu(cpu)) - return cpu; + goto preempt_en_rt; rcu_read_lock(); for_each_domain(cpu, sd) { @@ -668,6 +707,8 @@ } unlock: rcu_read_unlock(); +preempt_en_rt: + preempt_enable_rt(); return cpu; } /* @@ -745,14 +786,29 @@ #endif /* CONFIG_NO_HZ_COMMON */ #ifdef CONFIG_NO_HZ_FULL + +static int ksoftirqd_running(void) +{ + struct task_struct *softirqd; + + if (!IS_ENABLED(CONFIG_PREEMPT_RT_FULL)) + return 0; + softirqd = this_cpu_ksoftirqd(); + if (softirqd && softirqd->on_rq) + return 1; + return 0; +} + bool sched_can_stop_tick(void) { /* * More than one running task need preemption. * nr_running update is assumed to be visible * after IPI is sent from wakers. + * + * NOTE, RT: if ksoftirqd is awake, subtract it. */ - if (this_rq()->nr_running > 1) + if (this_rq()->nr_running - ksoftirqd_running() > 1) return false; return true; @@ -1198,6 +1254,18 @@ static int migration_cpu_stop(void *data); +static bool check_task_state(struct task_struct *p, long match_state) +{ + bool match = false; + + raw_spin_lock_irq(&p->pi_lock); + if (p->state == match_state || p->saved_state == match_state) + match = true; + raw_spin_unlock_irq(&p->pi_lock); + + return match; +} + /* * wait_task_inactive - wait for a thread to unschedule. * @@ -1242,7 +1310,7 @@ * is actually now running somewhere else! */ while (task_running(rq, p)) { - if (match_state && unlikely(p->state != match_state)) + if (match_state && !check_task_state(p, match_state)) return 0; cpu_relax(); } @@ -1257,7 +1325,8 @@ running = task_running(rq, p); queued = task_on_rq_queued(p); ncsw = 0; - if (!match_state || p->state == match_state) + if (!match_state || p->state == match_state || + p->saved_state == match_state) ncsw = p->nvcsw | LONG_MIN; /* sets MSB */ task_rq_unlock(rq, p, &flags); @@ -1482,10 +1551,6 @@ { activate_task(rq, p, en_flags); p->on_rq = TASK_ON_RQ_QUEUED; - - /* if a worker is waking up, notify workqueue */ - if (p->flags & PF_WQ_WORKER) - wq_worker_waking_up(p, cpu_of(rq)); } /* @@ -1699,8 +1764,27 @@ */ smp_mb__before_spinlock(); raw_spin_lock_irqsave(&p->pi_lock, flags); - if (!(p->state & state)) + if (!(p->state & state)) { + /* + * The task might be running due to a spinlock sleeper + * wakeup. Check the saved state and set it to running + * if the wakeup condition is true. + */ + if (!(wake_flags & WF_LOCK_SLEEPER)) { + if (p->saved_state & state) { + p->saved_state = TASK_RUNNING; + success = 1; + } + } goto out; + } + + /* + * If this is a regular wakeup, then we can unconditionally + * clear the saved state of a "lock sleeper". + */ + if (!(wake_flags & WF_LOCK_SLEEPER)) + p->saved_state = TASK_RUNNING; success = 1; /* we're going to change ->state */ cpu = task_cpu(p); @@ -1743,42 +1827,6 @@ } /** - * try_to_wake_up_local - try to wake up a local task with rq lock held - * @p: the thread to be awakened - * - * Put @p on the run-queue if it's not already there. The caller must - * ensure that this_rq() is locked, @p is bound to this_rq() and not - * the current task. - */ -static void try_to_wake_up_local(struct task_struct *p) -{ - struct rq *rq = task_rq(p); - - if (WARN_ON_ONCE(rq != this_rq()) || - WARN_ON_ONCE(p == current)) - return; - - lockdep_assert_held(&rq->lock); - - if (!raw_spin_trylock(&p->pi_lock)) { - raw_spin_unlock(&rq->lock); - raw_spin_lock(&p->pi_lock); - raw_spin_lock(&rq->lock); - } - - if (!(p->state & TASK_NORMAL)) - goto out; - - if (!task_on_rq_queued(p)) - ttwu_activate(rq, p, ENQUEUE_WAKEUP); - - ttwu_do_wakeup(rq, p, 0); - ttwu_stat(p, smp_processor_id(), 0); -out: - raw_spin_unlock(&p->pi_lock); -} - -/** * wake_up_process - Wake up a specific process * @p: The process to be woken up. * @@ -1792,11 +1840,23 @@ */ int wake_up_process(struct task_struct *p) { - WARN_ON(task_is_stopped_or_traced(p)); + WARN_ON(__task_is_stopped_or_traced(p)); return try_to_wake_up(p, TASK_NORMAL, 0); } EXPORT_SYMBOL(wake_up_process); +/** + * wake_up_lock_sleeper - Wake up a specific process blocked on a "sleeping lock" + * @p: The process to be woken up. + * + * Same as wake_up_process() above, but wake_flags=WF_LOCK_SLEEPER to indicate + * the nature of the wakeup. + */ +int wake_up_lock_sleeper(struct task_struct *p) +{ + return try_to_wake_up(p, TASK_ALL, WF_LOCK_SLEEPER); +} + int wake_up_state(struct task_struct *p, unsigned int state) { return try_to_wake_up(p, state, 0); @@ -1987,6 +2047,9 @@ p->on_cpu = 0; #endif init_task_preempt_count(p); +#ifdef CONFIG_HAVE_PREEMPT_LAZY + task_thread_info(p)->preempt_lazy_count = 0; +#endif #ifdef CONFIG_SMP plist_node_init(&p->pushable_tasks, MAX_PRIO); RB_CLEAR_NODE(&p->pushable_dl_tasks); @@ -2270,8 +2333,12 @@ finish_arch_post_lock_switch(); fire_sched_in_preempt_notifiers(current); + /* + * We use mmdrop_delayed() here so we don't have to do the + * full __mmdrop() when we are the last user. + */ if (mm) - mmdrop(mm); + mmdrop_delayed(mm); if (unlikely(prev_state == TASK_DEAD)) { if (prev->sched_class->task_dead) prev->sched_class->task_dead(prev); @@ -2696,6 +2763,133 @@ schedstat_inc(this_rq(), sched_count); } +#if defined(CONFIG_PREEMPT_RT_FULL) && defined(CONFIG_SMP) +#define MIGRATE_DISABLE_SET_AFFIN (1<<30) /* Can't make a negative */ +#define migrate_disabled_updated(p) ((p)->migrate_disable & MIGRATE_DISABLE_SET_AFFIN) +#define migrate_disable_count(p) ((p)->migrate_disable & ~MIGRATE_DISABLE_SET_AFFIN) + +static inline void update_migrate_disable(struct task_struct *p) +{ + const struct cpumask *mask; + + if (likely(!p->migrate_disable)) + return; + + /* Did we already update affinity? */ + if (unlikely(migrate_disabled_updated(p))) + return; + + /* + * Since this is always current we can get away with only locking + * rq->lock, the ->cpus_allowed value can normally only be changed + * while holding both p->pi_lock and rq->lock, but seeing that this + * is current, we cannot actually be waking up, so all code that + * relies on serialization against p->pi_lock is out of scope. + * + * Having rq->lock serializes us against things like + * set_cpus_allowed_ptr() that can still happen concurrently. + */ + mask = tsk_cpus_allowed(p); + + if (p->sched_class->set_cpus_allowed) + p->sched_class->set_cpus_allowed(p, mask); + /* mask==cpumask_of(task_cpu(p)) which has a cpumask_weight==1 */ + p->nr_cpus_allowed = 1; + + /* Let migrate_enable know to fix things back up */ + p->migrate_disable |= MIGRATE_DISABLE_SET_AFFIN; +} + +void migrate_disable(void) +{ + struct task_struct *p = current; + + if (in_atomic()) { +#ifdef CONFIG_SCHED_DEBUG + p->migrate_disable_atomic++; +#endif + return; + } + +#ifdef CONFIG_SCHED_DEBUG + if (unlikely(p->migrate_disable_atomic)) { + tracing_off(); + WARN_ON_ONCE(1); + } +#endif + + if (p->migrate_disable) { + p->migrate_disable++; + return; + } + + preempt_disable(); + preempt_lazy_disable(); + pin_current_cpu(); + p->migrate_disable = 1; + preempt_enable(); +} +EXPORT_SYMBOL(migrate_disable); + +void migrate_enable(void) +{ + struct task_struct *p = current; + const struct cpumask *mask; + unsigned long flags; + struct rq *rq; + + if (in_atomic()) { +#ifdef CONFIG_SCHED_DEBUG + p->migrate_disable_atomic--; +#endif + return; + } + +#ifdef CONFIG_SCHED_DEBUG + if (unlikely(p->migrate_disable_atomic)) { + tracing_off(); + WARN_ON_ONCE(1); + } +#endif + WARN_ON_ONCE(p->migrate_disable <= 0); + + if (migrate_disable_count(p) > 1) { + p->migrate_disable--; + return; + } + + preempt_disable(); + if (unlikely(migrate_disabled_updated(p))) { + /* + * Undo whatever update_migrate_disable() did, also see there + * about locking. + */ + rq = this_rq(); + raw_spin_lock_irqsave(&rq->lock, flags); + + /* + * Clearing migrate_disable causes tsk_cpus_allowed to + * show the tasks original cpu affinity. + */ + p->migrate_disable = 0; + mask = tsk_cpus_allowed(p); + if (p->sched_class->set_cpus_allowed) + p->sched_class->set_cpus_allowed(p, mask); + p->nr_cpus_allowed = cpumask_weight(mask); + raw_spin_unlock_irqrestore(&rq->lock, flags); + } else + p->migrate_disable = 0; + + unpin_current_cpu(); + preempt_enable(); + preempt_lazy_enable(); +} +EXPORT_SYMBOL(migrate_enable); +#else +static inline void update_migrate_disable(struct task_struct *p) { } +#define migrate_disabled_updated(p) 0 +#endif + /* * Pick up the highest-prio task: */ @@ -2799,6 +2993,8 @@ smp_mb__before_spinlock(); raw_spin_lock_irq(&rq->lock); + update_migrate_disable(prev); + switch_count = &prev->nivcsw; if (prev->state && !(preempt_count() & PREEMPT_ACTIVE)) { if (unlikely(signal_pending_state(prev->state, prev))) { @@ -2806,19 +3002,6 @@ } else { deactivate_task(rq, prev, DEQUEUE_SLEEP); prev->on_rq = 0; - - /* - * If a worker went to sleep, notify and ask workqueue - * whether it wants to wake up a task to maintain - * concurrency. - */ - if (prev->flags & PF_WQ_WORKER) { - struct task_struct *to_wakeup; - - to_wakeup = wq_worker_sleeping(prev, cpu); - if (to_wakeup) - try_to_wake_up_local(to_wakeup); - } } switch_count = &prev->nvcsw; } @@ -2828,6 +3011,7 @@ next = pick_next_task(rq, prev); clear_tsk_need_resched(prev); + clear_tsk_need_resched_lazy(prev); clear_preempt_need_resched(); rq->skip_clock_update = 0; @@ -2857,9 +3041,20 @@ static inline void sched_submit_work(struct task_struct *tsk) { - if (!tsk->state || tsk_is_pi_blocked(tsk)) + if (!tsk->state) return; /* + * If a worker went to sleep, notify and ask workqueue whether + * it wants to wake up a task to maintain concurrency. + */ + if (tsk->flags & PF_WQ_WORKER) + wq_worker_sleeping(tsk); + + + if (tsk_is_pi_blocked(tsk)) + return; + + /* * If we are going to sleep and we have plugged IO queued, * make sure to submit it to avoid deadlocks. */ @@ -2867,12 +3062,19 @@ blk_schedule_flush_plug(tsk); } +static inline void sched_update_worker(struct task_struct *tsk) +{ + if (tsk->flags & PF_WQ_WORKER) + wq_worker_running(tsk); +} + asmlinkage __visible void __sched schedule(void) { struct task_struct *tsk = current; sched_submit_work(tsk); __schedule(); + sched_update_worker(tsk); } EXPORT_SYMBOL(schedule); @@ -2922,9 +3124,26 @@ if (likely(!preemptible())) return; +#ifdef CONFIG_PREEMPT_LAZY + /* + * Check for lazy preemption + */ + if (current_thread_info()->preempt_lazy_count && + !test_thread_flag(TIF_NEED_RESCHED)) + return; +#endif do { __preempt_count_add(PREEMPT_ACTIVE); + /* + * The add/subtract must not be traced by the function + * tracer. But we still want to account for the + * preempt off latency tracer. Since the _notrace versions + * of add/subtract skip the accounting for latency tracer + * we must force it manually. + */ + start_critical_timings(); __schedule(); + stop_critical_timings(); __preempt_count_sub(PREEMPT_ACTIVE); /* @@ -4236,9 +4455,16 @@ static void __cond_resched(void) { - __preempt_count_add(PREEMPT_ACTIVE); - __schedule(); - __preempt_count_sub(PREEMPT_ACTIVE); + do { + __preempt_count_add(PREEMPT_ACTIVE); + __schedule(); + __preempt_count_sub(PREEMPT_ACTIVE); + /* + * Check again in case we missed a preemption + * opportunity between schedule and now. + */ + barrier(); + } while (need_resched()); } int __sched _cond_resched(void) @@ -4279,6 +4505,7 @@ } EXPORT_SYMBOL(__cond_resched_lock); +#ifndef CONFIG_PREEMPT_RT_FULL int __sched __cond_resched_softirq(void) { BUG_ON(!in_softirq()); @@ -4292,6 +4519,7 @@ return 0; } EXPORT_SYMBOL(__cond_resched_softirq); +#endif /** * yield - yield the current processor to other threads. @@ -4653,7 +4881,9 @@ /* Set the preempt count _outside_ the spinlocks! */ init_idle_preempt_count(idle, cpu); - +#ifdef CONFIG_HAVE_PREEMPT_LAZY + task_thread_info(idle)->preempt_lazy_count = 0; +#endif /* * The idle tasks have their own, simple scheduling class: */ @@ -4695,11 +4925,91 @@ void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask) { - if (p->sched_class && p->sched_class->set_cpus_allowed) - p->sched_class->set_cpus_allowed(p, new_mask); + if (!migrate_disabled_updated(p)) { + if (p->sched_class && p->sched_class->set_cpus_allowed) + p->sched_class->set_cpus_allowed(p, new_mask); + p->nr_cpus_allowed = cpumask_weight(new_mask); + } cpumask_copy(&p->cpus_allowed, new_mask); - p->nr_cpus_allowed = cpumask_weight(new_mask); +} + +static DEFINE_PER_CPU(struct cpumask, sched_cpumasks); +static DEFINE_MUTEX(sched_down_mutex); +static cpumask_t sched_down_cpumask; + +void tell_sched_cpu_down_begin(int cpu) +{ + mutex_lock(&sched_down_mutex); + cpumask_set_cpu(cpu, &sched_down_cpumask); + mutex_unlock(&sched_down_mutex); +} + +void tell_sched_cpu_down_done(int cpu) +{ + mutex_lock(&sched_down_mutex); + cpumask_clear_cpu(cpu, &sched_down_cpumask); + mutex_unlock(&sched_down_mutex); +} + +/** + * migrate_me - try to move the current task off this cpu + * + * Used by the pin_current_cpu() code to try to get tasks + * to move off the current CPU as it is going down. + * It will only move the task if the task isn't pinned to + * the CPU (with migrate_disable, affinity or NO_SETAFFINITY) + * and the task has to be in a RUNNING state. Otherwise the + * movement of the task will wake it up (change its state + * to running) when the task did not expect it. + * + * Returns 1 if it succeeded in moving the current task + * 0 otherwise. + */ +int migrate_me(void) +{ + struct task_struct *p = current; + struct migration_arg arg; + struct cpumask *cpumask; + struct cpumask *mask; + unsigned long flags; + unsigned int dest_cpu; + struct rq *rq; + + /* + * We can not migrate tasks bounded to a CPU or tasks not + * running. The movement of the task will wake it up. + */ + if (p->flags & PF_NO_SETAFFINITY || p->state) + return 0; + + mutex_lock(&sched_down_mutex); + rq = task_rq_lock(p, &flags); + + cpumask = &__get_cpu_var(sched_cpumasks); + mask = &p->cpus_allowed; + + cpumask_andnot(cpumask, mask, &sched_down_cpumask); + + if (!cpumask_weight(cpumask)) { + /* It's only on this CPU? */ + task_rq_unlock(rq, p, &flags); + mutex_unlock(&sched_down_mutex); + return 0; + } + + dest_cpu = cpumask_any_and(cpu_active_mask, cpumask); + + arg.task = p; + arg.dest_cpu = dest_cpu; + + task_rq_unlock(rq, p, &flags); + + stop_one_cpu(cpu_of(rq), migration_cpu_stop, &arg); + tlb_migrate_finish(p->mm); + mutex_unlock(&sched_down_mutex); + + return 1; } /* @@ -4745,7 +5055,7 @@ do_set_cpus_allowed(p, new_mask); /* Can the task run on the task's current CPU? If so, we're done */ - if (cpumask_test_cpu(task_cpu(p), new_mask)) + if (cpumask_test_cpu(task_cpu(p), new_mask) || __migrate_disabled(p)) goto out; dest_cpu = cpumask_any_and(cpu_active_mask, new_mask); @@ -4885,6 +5195,8 @@ #ifdef CONFIG_HOTPLUG_CPU +static DEFINE_PER_CPU(struct mm_struct *, idle_last_mm); + /* * Ensures that the idle task is using init_mm right before its cpu goes * offline. @@ -4899,7 +5211,11 @@ switch_mm(mm, &init_mm, current); finish_arch_post_lock_switch(); } - mmdrop(mm); + /* + * Defer the cleanup to an alive cpu. On RT we can neither + * call mmdrop() nor mmdrop_delayed() from here. + */ + per_cpu(idle_last_mm, smp_processor_id()) = mm; } /* @@ -5242,6 +5558,10 @@ case CPU_DEAD: calc_load_migrate(rq); + if (per_cpu(idle_last_mm, cpu)) { + mmdrop(per_cpu(idle_last_mm, cpu)); + per_cpu(idle_last_mm, cpu) = NULL; + } break; #endif } @@ -7183,7 +7503,8 @@ #ifdef CONFIG_DEBUG_ATOMIC_SLEEP static inline int preempt_count_equals(int preempt_offset) { - int nested = (preempt_count() & ~PREEMPT_ACTIVE) + rcu_preempt_depth(); + int nested = (preempt_count() & ~PREEMPT_ACTIVE) + + sched_rcu_preempt_depth(); return (nested == preempt_offset); } diff -Nur linux-3.18.14.orig/kernel/sched/cputime.c linux-3.18.14-rt/kernel/sched/cputime.c --- linux-3.18.14.orig/kernel/sched/cputime.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/sched/cputime.c 2015-05-31 15:32:48.893635363 -0500 @@ -675,37 +675,45 @@ void vtime_account_system(struct task_struct *tsk) { - write_seqlock(&tsk->vtime_seqlock); + raw_spin_lock(&tsk->vtime_lock); + write_seqcount_begin(&tsk->vtime_seq); __vtime_account_system(tsk); - write_sequnlock(&tsk->vtime_seqlock); + write_seqcount_end(&tsk->vtime_seq); + raw_spin_unlock(&tsk->vtime_lock); } void vtime_gen_account_irq_exit(struct task_struct *tsk) { - write_seqlock(&tsk->vtime_seqlock); + raw_spin_lock(&tsk->vtime_lock); + write_seqcount_begin(&tsk->vtime_seq); __vtime_account_system(tsk); if (context_tracking_in_user()) tsk->vtime_snap_whence = VTIME_USER; - write_sequnlock(&tsk->vtime_seqlock); + write_seqcount_end(&tsk->vtime_seq); + raw_spin_unlock(&tsk->vtime_lock); } void vtime_account_user(struct task_struct *tsk) { cputime_t delta_cpu; - write_seqlock(&tsk->vtime_seqlock); + raw_spin_lock(&tsk->vtime_lock); + write_seqcount_begin(&tsk->vtime_seq); delta_cpu = get_vtime_delta(tsk); tsk->vtime_snap_whence = VTIME_SYS; account_user_time(tsk, delta_cpu, cputime_to_scaled(delta_cpu)); - write_sequnlock(&tsk->vtime_seqlock); + write_seqcount_end(&tsk->vtime_seq); + raw_spin_unlock(&tsk->vtime_lock); } void vtime_user_enter(struct task_struct *tsk) { - write_seqlock(&tsk->vtime_seqlock); + raw_spin_lock(&tsk->vtime_lock); + write_seqcount_begin(&tsk->vtime_seq); __vtime_account_system(tsk); tsk->vtime_snap_whence = VTIME_USER; - write_sequnlock(&tsk->vtime_seqlock); + write_seqcount_end(&tsk->vtime_seq); + raw_spin_unlock(&tsk->vtime_lock); } void vtime_guest_enter(struct task_struct *tsk) @@ -717,19 +725,23 @@ * synchronization against the reader (task_gtime()) * that can thus safely catch up with a tickless delta. */ - write_seqlock(&tsk->vtime_seqlock); + raw_spin_lock(&tsk->vtime_lock); + write_seqcount_begin(&tsk->vtime_seq); __vtime_account_system(tsk); current->flags |= PF_VCPU; - write_sequnlock(&tsk->vtime_seqlock); + write_seqcount_end(&tsk->vtime_seq); + raw_spin_unlock(&tsk->vtime_lock); } EXPORT_SYMBOL_GPL(vtime_guest_enter); void vtime_guest_exit(struct task_struct *tsk) { - write_seqlock(&tsk->vtime_seqlock); + raw_spin_lock(&tsk->vtime_lock); + write_seqcount_begin(&tsk->vtime_seq); __vtime_account_system(tsk); current->flags &= ~PF_VCPU; - write_sequnlock(&tsk->vtime_seqlock); + write_seqcount_end(&tsk->vtime_seq); + raw_spin_unlock(&tsk->vtime_lock); } EXPORT_SYMBOL_GPL(vtime_guest_exit); @@ -742,24 +754,30 @@ void arch_vtime_task_switch(struct task_struct *prev) { - write_seqlock(&prev->vtime_seqlock); + raw_spin_lock(&prev->vtime_lock); + write_seqcount_begin(&prev->vtime_seq); prev->vtime_snap_whence = VTIME_SLEEPING; - write_sequnlock(&prev->vtime_seqlock); + write_seqcount_end(&prev->vtime_seq); + raw_spin_unlock(&prev->vtime_lock); - write_seqlock(¤t->vtime_seqlock); + raw_spin_lock(¤t->vtime_lock); + write_seqcount_begin(¤t->vtime_seq); current->vtime_snap_whence = VTIME_SYS; current->vtime_snap = sched_clock_cpu(smp_processor_id()); - write_sequnlock(¤t->vtime_seqlock); + write_seqcount_end(¤t->vtime_seq); + raw_spin_unlock(¤t->vtime_lock); } void vtime_init_idle(struct task_struct *t, int cpu) { unsigned long flags; - write_seqlock_irqsave(&t->vtime_seqlock, flags); + raw_spin_lock_irqsave(&t->vtime_lock, flags); + write_seqcount_begin(&t->vtime_seq); t->vtime_snap_whence = VTIME_SYS; t->vtime_snap = sched_clock_cpu(cpu); - write_sequnlock_irqrestore(&t->vtime_seqlock, flags); + write_seqcount_end(&t->vtime_seq); + raw_spin_unlock_irqrestore(&t->vtime_lock, flags); } cputime_t task_gtime(struct task_struct *t) @@ -768,13 +786,13 @@ cputime_t gtime; do { - seq = read_seqbegin(&t->vtime_seqlock); + seq = read_seqcount_begin(&t->vtime_seq); gtime = t->gtime; if (t->flags & PF_VCPU) gtime += vtime_delta(t); - } while (read_seqretry(&t->vtime_seqlock, seq)); + } while (read_seqcount_retry(&t->vtime_seq, seq)); return gtime; } @@ -797,7 +815,7 @@ *udelta = 0; *sdelta = 0; - seq = read_seqbegin(&t->vtime_seqlock); + seq = read_seqcount_begin(&t->vtime_seq); if (u_dst) *u_dst = *u_src; @@ -821,7 +839,7 @@ if (t->vtime_snap_whence == VTIME_SYS) *sdelta = delta; } - } while (read_seqretry(&t->vtime_seqlock, seq)); + } while (read_seqcount_retry(&t->vtime_seq, seq)); } diff -Nur linux-3.18.14.orig/kernel/sched/deadline.c linux-3.18.14-rt/kernel/sched/deadline.c --- linux-3.18.14.orig/kernel/sched/deadline.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/sched/deadline.c 2015-05-31 15:32:48.893635363 -0500 @@ -570,6 +570,7 @@ hrtimer_init(timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); timer->function = dl_task_timer; + timer->irqsafe = 1; } static diff -Nur linux-3.18.14.orig/kernel/sched/debug.c linux-3.18.14-rt/kernel/sched/debug.c --- linux-3.18.14.orig/kernel/sched/debug.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/sched/debug.c 2015-05-31 15:32:48.897635363 -0500 @@ -256,6 +256,9 @@ P(rt_throttled); PN(rt_time); PN(rt_runtime); +#ifdef CONFIG_SMP + P(rt_nr_migratory); +#endif #undef PN #undef P @@ -634,6 +637,10 @@ #endif P(policy); P(prio); +#ifdef CONFIG_PREEMPT_RT_FULL + P(migrate_disable); +#endif + P(nr_cpus_allowed); #undef PN #undef __PN #undef P diff -Nur linux-3.18.14.orig/kernel/sched/fair.c linux-3.18.14-rt/kernel/sched/fair.c --- linux-3.18.14.orig/kernel/sched/fair.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/sched/fair.c 2015-05-31 15:32:48.897635363 -0500 @@ -2951,7 +2951,7 @@ ideal_runtime = sched_slice(cfs_rq, curr); delta_exec = curr->sum_exec_runtime - curr->prev_sum_exec_runtime; if (delta_exec > ideal_runtime) { - resched_curr(rq_of(cfs_rq)); + resched_curr_lazy(rq_of(cfs_rq)); /* * The current task ran long enough, ensure it doesn't get * re-elected due to buddy favours. @@ -2975,7 +2975,7 @@ return; if (delta > ideal_runtime) - resched_curr(rq_of(cfs_rq)); + resched_curr_lazy(rq_of(cfs_rq)); } static void @@ -3115,7 +3115,7 @@ * validating it and just reschedule. */ if (queued) { - resched_curr(rq_of(cfs_rq)); + resched_curr_lazy(rq_of(cfs_rq)); return; } /* @@ -3306,7 +3306,7 @@ * hierarchy can be throttled */ if (!assign_cfs_rq_runtime(cfs_rq) && likely(cfs_rq->curr)) - resched_curr(rq_of(cfs_rq)); + resched_curr_lazy(rq_of(cfs_rq)); } static __always_inline @@ -3925,7 +3925,7 @@ if (delta < 0) { if (rq->curr == p) - resched_curr(rq); + resched_curr_lazy(rq); return; } hrtick_start(rq, delta); @@ -4792,7 +4792,7 @@ return; preempt: - resched_curr(rq); + resched_curr_lazy(rq); /* * Only set the backward buddy when the current task is still * on the rq. This can happen when a wakeup gets interleaved @@ -7576,7 +7576,7 @@ * 'current' within the tree based on its new key value. */ swap(curr->vruntime, se->vruntime); - resched_curr(rq); + resched_curr_lazy(rq); } se->vruntime -= cfs_rq->min_vruntime; @@ -7601,7 +7601,7 @@ */ if (rq->curr == p) { if (p->prio > oldprio) - resched_curr(rq); + resched_curr_lazy(rq); } else check_preempt_curr(rq, p, 0); } diff -Nur linux-3.18.14.orig/kernel/sched/features.h linux-3.18.14-rt/kernel/sched/features.h --- linux-3.18.14.orig/kernel/sched/features.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/sched/features.h 2015-05-31 15:32:48.897635363 -0500 @@ -50,12 +50,18 @@ */ SCHED_FEAT(NONTASK_CAPACITY, true) +#ifdef CONFIG_PREEMPT_RT_FULL +SCHED_FEAT(TTWU_QUEUE, false) +# ifdef CONFIG_PREEMPT_LAZY +SCHED_FEAT(PREEMPT_LAZY, true) +# endif +#else /* * Queue remote wakeups on the target CPU and process them * using the scheduler IPI. Reduces rq->lock contention/bounces. */ SCHED_FEAT(TTWU_QUEUE, true) - +#endif SCHED_FEAT(FORCE_SD_OVERLAP, false) SCHED_FEAT(RT_RUNTIME_SHARE, true) SCHED_FEAT(LB_MIN, false) diff -Nur linux-3.18.14.orig/kernel/sched/Makefile linux-3.18.14-rt/kernel/sched/Makefile --- linux-3.18.14.orig/kernel/sched/Makefile 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/sched/Makefile 2015-05-31 15:32:48.861635363 -0500 @@ -13,7 +13,7 @@ obj-y += core.o proc.o clock.o cputime.o obj-y += idle_task.o fair.o rt.o deadline.o stop_task.o -obj-y += wait.o completion.o idle.o +obj-y += wait.o wait-simple.o work-simple.o completion.o idle.o obj-$(CONFIG_SMP) += cpupri.o cpudeadline.o obj-$(CONFIG_SCHED_AUTOGROUP) += auto_group.o obj-$(CONFIG_SCHEDSTATS) += stats.o diff -Nur linux-3.18.14.orig/kernel/sched/rt.c linux-3.18.14-rt/kernel/sched/rt.c --- linux-3.18.14.orig/kernel/sched/rt.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/sched/rt.c 2015-05-31 15:32:48.897635363 -0500 @@ -43,6 +43,7 @@ hrtimer_init(&rt_b->rt_period_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); + rt_b->rt_period_timer.irqsafe = 1; rt_b->rt_period_timer.function = sched_rt_period_timer; } diff -Nur linux-3.18.14.orig/kernel/sched/sched.h linux-3.18.14-rt/kernel/sched/sched.h --- linux-3.18.14.orig/kernel/sched/sched.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/sched/sched.h 2015-05-31 15:32:48.897635363 -0500 @@ -1018,6 +1018,7 @@ #define WF_SYNC 0x01 /* waker goes to sleep after wakeup */ #define WF_FORK 0x02 /* child wakeup after fork */ #define WF_MIGRATED 0x4 /* internal use, task got migrated */ +#define WF_LOCK_SLEEPER 0x08 /* wakeup spinlock "sleeper" */ /* * To aid in avoiding the subversion of "niceness" due to uneven distribution @@ -1210,6 +1211,15 @@ extern void resched_curr(struct rq *rq); extern void resched_cpu(int cpu); +#ifdef CONFIG_PREEMPT_LAZY +extern void resched_curr_lazy(struct rq *rq); +#else +static inline void resched_curr_lazy(struct rq *rq) +{ + resched_curr(rq); +} +#endif + extern struct rt_bandwidth def_rt_bandwidth; extern void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime); diff -Nur linux-3.18.14.orig/kernel/sched/wait-simple.c linux-3.18.14-rt/kernel/sched/wait-simple.c --- linux-3.18.14.orig/kernel/sched/wait-simple.c 1969-12-31 18:00:00.000000000 -0600 +++ linux-3.18.14-rt/kernel/sched/wait-simple.c 2015-05-31 15:32:48.897635363 -0500 @@ -0,0 +1,115 @@ +/* + * Simple waitqueues without fancy flags and callbacks + * + * (C) 2011 Thomas Gleixner + * + * Based on kernel/wait.c + * + * For licencing details see kernel-base/COPYING + */ +#include +#include +#include +#include + +/* Adds w to head->list. Must be called with head->lock locked. */ +static inline void __swait_enqueue(struct swait_head *head, struct swaiter *w) +{ + list_add(&w->node, &head->list); + /* We can't let the condition leak before the setting of head */ + smp_mb(); +} + +/* Removes w from head->list. Must be called with head->lock locked. */ +static inline void __swait_dequeue(struct swaiter *w) +{ + list_del_init(&w->node); +} + +void __init_swait_head(struct swait_head *head, struct lock_class_key *key) +{ + raw_spin_lock_init(&head->lock); + lockdep_set_class(&head->lock, key); + INIT_LIST_HEAD(&head->list); +} +EXPORT_SYMBOL(__init_swait_head); + +void swait_prepare_locked(struct swait_head *head, struct swaiter *w) +{ + w->task = current; + if (list_empty(&w->node)) + __swait_enqueue(head, w); +} + +void swait_prepare(struct swait_head *head, struct swaiter *w, int state) +{ + unsigned long flags; + + raw_spin_lock_irqsave(&head->lock, flags); + swait_prepare_locked(head, w); + __set_current_state(state); + raw_spin_unlock_irqrestore(&head->lock, flags); +} +EXPORT_SYMBOL(swait_prepare); + +void swait_finish_locked(struct swait_head *head, struct swaiter *w) +{ + __set_current_state(TASK_RUNNING); + if (w->task) + __swait_dequeue(w); +} + +void swait_finish(struct swait_head *head, struct swaiter *w) +{ + unsigned long flags; + + __set_current_state(TASK_RUNNING); + if (w->task) { + raw_spin_lock_irqsave(&head->lock, flags); + __swait_dequeue(w); + raw_spin_unlock_irqrestore(&head->lock, flags); + } +} +EXPORT_SYMBOL(swait_finish); + +unsigned int +__swait_wake_locked(struct swait_head *head, unsigned int state, unsigned int num) +{ + struct swaiter *curr, *next; + int woken = 0; + + list_for_each_entry_safe(curr, next, &head->list, node) { + if (wake_up_state(curr->task, state)) { + __swait_dequeue(curr); + /* + * The waiting task can free the waiter as + * soon as curr->task = NULL is written, + * without taking any locks. A memory barrier + * is required here to prevent the following + * store to curr->task from getting ahead of + * the dequeue operation. + */ + smp_wmb(); + curr->task = NULL; + if (++woken == num) + break; + } + } + return woken; +} + +unsigned int +__swait_wake(struct swait_head *head, unsigned int state, unsigned int num) +{ + unsigned long flags; + int woken; + + if (!swaitqueue_active(head)) + return 0; + + raw_spin_lock_irqsave(&head->lock, flags); + woken = __swait_wake_locked(head, state, num); + raw_spin_unlock_irqrestore(&head->lock, flags); + return woken; +} +EXPORT_SYMBOL(__swait_wake); diff -Nur linux-3.18.14.orig/kernel/sched/work-simple.c linux-3.18.14-rt/kernel/sched/work-simple.c --- linux-3.18.14.orig/kernel/sched/work-simple.c 1969-12-31 18:00:00.000000000 -0600 +++ linux-3.18.14-rt/kernel/sched/work-simple.c 2015-05-31 15:32:48.901635363 -0500 @@ -0,0 +1,172 @@ +/* + * Copyright (C) 2014 BMW Car IT GmbH, Daniel Wagner daniel.wagner@bmw-carit.de + * + * Provides a framework for enqueuing callbacks from irq context + * PREEMPT_RT_FULL safe. The callbacks are executed in kthread context. + */ + +#include +#include +#include +#include +#include + +#define SWORK_EVENT_PENDING (1 << 0) + +static DEFINE_MUTEX(worker_mutex); +static struct sworker *glob_worker; + +struct sworker { + struct list_head events; + struct swait_head wq; + + raw_spinlock_t lock; + + struct task_struct *task; + int refs; +}; + +static bool swork_readable(struct sworker *worker) +{ + bool r; + + if (kthread_should_stop()) + return true; + + raw_spin_lock_irq(&worker->lock); + r = !list_empty(&worker->events); + raw_spin_unlock_irq(&worker->lock); + + return r; +} + +static int swork_kthread(void *arg) +{ + struct sworker *worker = arg; + + for (;;) { + swait_event_interruptible(worker->wq, + swork_readable(worker)); + if (kthread_should_stop()) + break; + + raw_spin_lock_irq(&worker->lock); + while (!list_empty(&worker->events)) { + struct swork_event *sev; + + sev = list_first_entry(&worker->events, + struct swork_event, item); + list_del(&sev->item); + raw_spin_unlock_irq(&worker->lock); + + WARN_ON_ONCE(!test_and_clear_bit(SWORK_EVENT_PENDING, + &sev->flags)); + sev->func(sev); + raw_spin_lock_irq(&worker->lock); + } + raw_spin_unlock_irq(&worker->lock); + } + return 0; +} + +static struct sworker *swork_create(void) +{ + struct sworker *worker; + + worker = kzalloc(sizeof(*worker), GFP_KERNEL); + if (!worker) + return ERR_PTR(-ENOMEM); + + INIT_LIST_HEAD(&worker->events); + raw_spin_lock_init(&worker->lock); + init_swait_head(&worker->wq); + + worker->task = kthread_run(swork_kthread, worker, "kswork"); + if (IS_ERR(worker->task)) { + kfree(worker); + return ERR_PTR(-ENOMEM); + } + + return worker; +} + +static void swork_destroy(struct sworker *worker) +{ + kthread_stop(worker->task); + + WARN_ON(!list_empty(&worker->events)); + kfree(worker); +} + +/** + * swork_queue - queue swork + * + * Returns %false if @work was already on a queue, %true otherwise. + * + * The work is queued and processed on a random CPU + */ +bool swork_queue(struct swork_event *sev) +{ + unsigned long flags; + + if (test_and_set_bit(SWORK_EVENT_PENDING, &sev->flags)) + return false; + + raw_spin_lock_irqsave(&glob_worker->lock, flags); + list_add_tail(&sev->item, &glob_worker->events); + raw_spin_unlock_irqrestore(&glob_worker->lock, flags); + + swait_wake(&glob_worker->wq); + return true; +} +EXPORT_SYMBOL_GPL(swork_queue); + +/** + * swork_get - get an instance of the sworker + * + * Returns an negative error code if the initialization if the worker did not + * work, %0 otherwise. + * + */ +int swork_get(void) +{ + struct sworker *worker; + + mutex_lock(&worker_mutex); + if (!glob_worker) { + worker = swork_create(); + if (IS_ERR(worker)) { + mutex_unlock(&worker_mutex); + return -ENOMEM; + } + + glob_worker = worker; + } + + glob_worker->refs++; + mutex_unlock(&worker_mutex); + + return 0; +} +EXPORT_SYMBOL_GPL(swork_get); + +/** + * swork_put - puts an instance of the sworker + * + * Will destroy the sworker thread. This function must not be called until all + * queued events have been completed. + */ +void swork_put(void) +{ + mutex_lock(&worker_mutex); + + glob_worker->refs--; + if (glob_worker->refs > 0) + goto out; + + swork_destroy(glob_worker); + glob_worker = NULL; +out: + mutex_unlock(&worker_mutex); +} +EXPORT_SYMBOL_GPL(swork_put); diff -Nur linux-3.18.14.orig/kernel/signal.c linux-3.18.14-rt/kernel/signal.c --- linux-3.18.14.orig/kernel/signal.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/signal.c 2015-05-31 15:32:48.921635363 -0500 @@ -14,6 +14,7 @@ #include #include #include +#include #include #include #include @@ -352,13 +353,45 @@ return false; } +#ifdef __HAVE_ARCH_CMPXCHG +static inline struct sigqueue *get_task_cache(struct task_struct *t) +{ + struct sigqueue *q = t->sigqueue_cache; + + if (cmpxchg(&t->sigqueue_cache, q, NULL) != q) + return NULL; + return q; +} + +static inline int put_task_cache(struct task_struct *t, struct sigqueue *q) +{ + if (cmpxchg(&t->sigqueue_cache, NULL, q) == NULL) + return 0; + return 1; +} + +#else + +static inline struct sigqueue *get_task_cache(struct task_struct *t) +{ + return NULL; +} + +static inline int put_task_cache(struct task_struct *t, struct sigqueue *q) +{ + return 1; +} + +#endif + /* * allocate a new signal queue record * - this may be called without locks if and only if t == current, otherwise an * appropriate lock must be held to stop the target task from exiting */ static struct sigqueue * -__sigqueue_alloc(int sig, struct task_struct *t, gfp_t flags, int override_rlimit) +__sigqueue_do_alloc(int sig, struct task_struct *t, gfp_t flags, + int override_rlimit, int fromslab) { struct sigqueue *q = NULL; struct user_struct *user; @@ -375,7 +408,10 @@ if (override_rlimit || atomic_read(&user->sigpending) <= task_rlimit(t, RLIMIT_SIGPENDING)) { - q = kmem_cache_alloc(sigqueue_cachep, flags); + if (!fromslab) + q = get_task_cache(t); + if (!q) + q = kmem_cache_alloc(sigqueue_cachep, flags); } else { print_dropped_signal(sig); } @@ -392,6 +428,13 @@ return q; } +static struct sigqueue * +__sigqueue_alloc(int sig, struct task_struct *t, gfp_t flags, + int override_rlimit) +{ + return __sigqueue_do_alloc(sig, t, flags, override_rlimit, 0); +} + static void __sigqueue_free(struct sigqueue *q) { if (q->flags & SIGQUEUE_PREALLOC) @@ -401,6 +444,21 @@ kmem_cache_free(sigqueue_cachep, q); } +static void sigqueue_free_current(struct sigqueue *q) +{ + struct user_struct *up; + + if (q->flags & SIGQUEUE_PREALLOC) + return; + + up = q->user; + if (rt_prio(current->normal_prio) && !put_task_cache(current, q)) { + atomic_dec(&up->sigpending); + free_uid(up); + } else + __sigqueue_free(q); +} + void flush_sigqueue(struct sigpending *queue) { struct sigqueue *q; @@ -414,6 +472,21 @@ } /* + * Called from __exit_signal. Flush tsk->pending and + * tsk->sigqueue_cache + */ +void flush_task_sigqueue(struct task_struct *tsk) +{ + struct sigqueue *q; + + flush_sigqueue(&tsk->pending); + + q = get_task_cache(tsk); + if (q) + kmem_cache_free(sigqueue_cachep, q); +} + +/* * Flush all pending signals for a task. */ void __flush_signals(struct task_struct *t) @@ -565,7 +638,7 @@ still_pending: list_del_init(&first->list); copy_siginfo(info, &first->info); - __sigqueue_free(first); + sigqueue_free_current(first); } else { /* * Ok, it wasn't in the queue. This must be @@ -611,6 +684,8 @@ { int signr; + WARN_ON_ONCE(tsk != current); + /* We only dequeue private signals from ourselves, we don't let * signalfd steal them */ @@ -1207,8 +1282,8 @@ * We don't want to have recursive SIGSEGV's etc, for example, * that is why we also clear SIGNAL_UNKILLABLE. */ -int -force_sig_info(int sig, struct siginfo *info, struct task_struct *t) +static int +do_force_sig_info(int sig, struct siginfo *info, struct task_struct *t) { unsigned long int flags; int ret, blocked, ignored; @@ -1233,6 +1308,39 @@ return ret; } +int force_sig_info(int sig, struct siginfo *info, struct task_struct *t) +{ +/* + * On some archs, PREEMPT_RT has to delay sending a signal from a trap + * since it can not enable preemption, and the signal code's spin_locks + * turn into mutexes. Instead, it must set TIF_NOTIFY_RESUME which will + * send the signal on exit of the trap. + */ +#ifdef ARCH_RT_DELAYS_SIGNAL_SEND + if (in_atomic()) { + if (WARN_ON_ONCE(t != current)) + return 0; + if (WARN_ON_ONCE(t->forced_info.si_signo)) + return 0; + + if (is_si_special(info)) { + WARN_ON_ONCE(info != SEND_SIG_PRIV); + t->forced_info.si_signo = sig; + t->forced_info.si_errno = 0; + t->forced_info.si_code = SI_KERNEL; + t->forced_info.si_pid = 0; + t->forced_info.si_uid = 0; + } else { + t->forced_info = *info; + } + + set_tsk_thread_flag(t, TIF_NOTIFY_RESUME); + return 0; + } +#endif + return do_force_sig_info(sig, info, t); +} + /* * Nuke all other threads in the group. */ @@ -1267,12 +1375,12 @@ * Disable interrupts early to avoid deadlocks. * See rcu_read_unlock() comment header for details. */ - local_irq_save(*flags); + local_irq_save_nort(*flags); rcu_read_lock(); sighand = rcu_dereference(tsk->sighand); if (unlikely(sighand == NULL)) { rcu_read_unlock(); - local_irq_restore(*flags); + local_irq_restore_nort(*flags); break; } @@ -1283,7 +1391,7 @@ } spin_unlock(&sighand->siglock); rcu_read_unlock(); - local_irq_restore(*flags); + local_irq_restore_nort(*flags); } return sighand; @@ -1528,7 +1636,8 @@ */ struct sigqueue *sigqueue_alloc(void) { - struct sigqueue *q = __sigqueue_alloc(-1, current, GFP_KERNEL, 0); + /* Preallocated sigqueue objects always from the slabcache ! */ + struct sigqueue *q = __sigqueue_do_alloc(-1, current, GFP_KERNEL, 0, 1); if (q) q->flags |= SIGQUEUE_PREALLOC; @@ -1889,15 +1998,7 @@ if (gstop_done && ptrace_reparented(current)) do_notify_parent_cldstop(current, false, why); - /* - * Don't want to allow preemption here, because - * sys_ptrace() needs this task to be inactive. - * - * XXX: implement read_unlock_no_resched(). - */ - preempt_disable(); read_unlock(&tasklist_lock); - preempt_enable_no_resched(); freezable_schedule(); } else { /* diff -Nur linux-3.18.14.orig/kernel/softirq.c linux-3.18.14-rt/kernel/softirq.c --- linux-3.18.14.orig/kernel/softirq.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/softirq.c 2015-05-31 15:32:48.921635363 -0500 @@ -21,10 +21,12 @@ #include #include #include +#include #include #include #include #include +#include #include #define CREATE_TRACE_POINTS @@ -62,6 +64,98 @@ "TASKLET", "SCHED", "HRTIMER", "RCU" }; +#ifdef CONFIG_NO_HZ_COMMON +# ifdef CONFIG_PREEMPT_RT_FULL + +struct softirq_runner { + struct task_struct *runner[NR_SOFTIRQS]; +}; + +static DEFINE_PER_CPU(struct softirq_runner, softirq_runners); + +static inline void softirq_set_runner(unsigned int sirq) +{ + struct softirq_runner *sr = &__get_cpu_var(softirq_runners); + + sr->runner[sirq] = current; +} + +static inline void softirq_clr_runner(unsigned int sirq) +{ + struct softirq_runner *sr = &__get_cpu_var(softirq_runners); + + sr->runner[sirq] = NULL; +} + +/* + * On preempt-rt a softirq running context might be blocked on a + * lock. There might be no other runnable task on this CPU because the + * lock owner runs on some other CPU. So we have to go into idle with + * the pending bit set. Therefor we need to check this otherwise we + * warn about false positives which confuses users and defeats the + * whole purpose of this test. + * + * This code is called with interrupts disabled. + */ +void softirq_check_pending_idle(void) +{ + static int rate_limit; + struct softirq_runner *sr = &__get_cpu_var(softirq_runners); + u32 warnpending; + int i; + + if (rate_limit >= 10) + return; + + warnpending = local_softirq_pending() & SOFTIRQ_STOP_IDLE_MASK; + for (i = 0; i < NR_SOFTIRQS; i++) { + struct task_struct *tsk = sr->runner[i]; + + /* + * The wakeup code in rtmutex.c wakes up the task + * _before_ it sets pi_blocked_on to NULL under + * tsk->pi_lock. So we need to check for both: state + * and pi_blocked_on. + */ + if (tsk) { + raw_spin_lock(&tsk->pi_lock); + if (tsk->pi_blocked_on || tsk->state == TASK_RUNNING) { + /* Clear all bits pending in that task */ + warnpending &= ~(tsk->softirqs_raised); + warnpending &= ~(1 << i); + } + raw_spin_unlock(&tsk->pi_lock); + } + } + + if (warnpending) { + printk(KERN_ERR "NOHZ: local_softirq_pending %02x\n", + warnpending); + rate_limit++; + } +} +# else +/* + * On !PREEMPT_RT we just printk rate limited: + */ +void softirq_check_pending_idle(void) +{ + static int rate_limit; + + if (rate_limit < 10 && + (local_softirq_pending() & SOFTIRQ_STOP_IDLE_MASK)) { + printk(KERN_ERR "NOHZ: local_softirq_pending %02x\n", + local_softirq_pending()); + rate_limit++; + } +} +# endif + +#else /* !CONFIG_NO_HZ_COMMON */ +static inline void softirq_set_runner(unsigned int sirq) { } +static inline void softirq_clr_runner(unsigned int sirq) { } +#endif + /* * we cannot loop indefinitely here to avoid userspace starvation, * but we also don't want to introduce a worst case 1/HZ latency @@ -77,6 +171,70 @@ wake_up_process(tsk); } +static void handle_softirq(unsigned int vec_nr) +{ + struct softirq_action *h = softirq_vec + vec_nr; + int prev_count; + + prev_count = preempt_count(); + + kstat_incr_softirqs_this_cpu(vec_nr); + + trace_softirq_entry(vec_nr); + h->action(h); + trace_softirq_exit(vec_nr); + if (unlikely(prev_count != preempt_count())) { + pr_err("huh, entered softirq %u %s %p with preempt_count %08x, exited with %08x?\n", + vec_nr, softirq_to_name[vec_nr], h->action, + prev_count, preempt_count()); + preempt_count_set(prev_count); + } +} + +#ifndef CONFIG_PREEMPT_RT_FULL +static inline int ksoftirqd_softirq_pending(void) +{ + return local_softirq_pending(); +} + +static void handle_pending_softirqs(u32 pending, int need_rcu_bh_qs) +{ + struct softirq_action *h = softirq_vec; + int softirq_bit; + + local_irq_enable(); + + h = softirq_vec; + + while ((softirq_bit = ffs(pending))) { + unsigned int vec_nr; + + h += softirq_bit - 1; + vec_nr = h - softirq_vec; + handle_softirq(vec_nr); + + h++; + pending >>= softirq_bit; + } + + if (need_rcu_bh_qs) + rcu_bh_qs(); + local_irq_disable(); +} + +static void run_ksoftirqd(unsigned int cpu) +{ + local_irq_disable(); + if (ksoftirqd_softirq_pending()) { + __do_softirq(); + rcu_note_context_switch(cpu); + local_irq_enable(); + cond_resched(); + return; + } + local_irq_enable(); +} + /* * preempt_count and SOFTIRQ_OFFSET usage: * - preempt_count is changed by SOFTIRQ_OFFSET on entering or leaving @@ -228,10 +386,8 @@ unsigned long end = jiffies + MAX_SOFTIRQ_TIME; unsigned long old_flags = current->flags; int max_restart = MAX_SOFTIRQ_RESTART; - struct softirq_action *h; bool in_hardirq; __u32 pending; - int softirq_bit; /* * Mask out PF_MEMALLOC s current task context is borrowed for the @@ -250,36 +406,7 @@ /* Reset the pending bitmask before enabling irqs */ set_softirq_pending(0); - local_irq_enable(); - - h = softirq_vec; - - while ((softirq_bit = ffs(pending))) { - unsigned int vec_nr; - int prev_count; - - h += softirq_bit - 1; - - vec_nr = h - softirq_vec; - prev_count = preempt_count(); - - kstat_incr_softirqs_this_cpu(vec_nr); - - trace_softirq_entry(vec_nr); - h->action(h); - trace_softirq_exit(vec_nr); - if (unlikely(prev_count != preempt_count())) { - pr_err("huh, entered softirq %u %s %p with preempt_count %08x, exited with %08x?\n", - vec_nr, softirq_to_name[vec_nr], h->action, - prev_count, preempt_count()); - preempt_count_set(prev_count); - } - h++; - pending >>= softirq_bit; - } - - rcu_bh_qs(); - local_irq_disable(); + handle_pending_softirqs(pending, 1); pending = local_softirq_pending(); if (pending) { @@ -316,6 +443,285 @@ } /* + * This function must run with irqs disabled! + */ +void raise_softirq_irqoff(unsigned int nr) +{ + __raise_softirq_irqoff(nr); + + /* + * If we're in an interrupt or softirq, we're done + * (this also catches softirq-disabled code). We will + * actually run the softirq once we return from + * the irq or softirq. + * + * Otherwise we wake up ksoftirqd to make sure we + * schedule the softirq soon. + */ + if (!in_interrupt()) + wakeup_softirqd(); +} + +void __raise_softirq_irqoff(unsigned int nr) +{ + trace_softirq_raise(nr); + or_softirq_pending(1UL << nr); +} + +static inline void local_bh_disable_nort(void) { local_bh_disable(); } +static inline void _local_bh_enable_nort(void) { _local_bh_enable(); } +static void ksoftirqd_set_sched_params(unsigned int cpu) { } +static void ksoftirqd_clr_sched_params(unsigned int cpu, bool online) { } + +#else /* !PREEMPT_RT_FULL */ + +/* + * On RT we serialize softirq execution with a cpu local lock per softirq + */ +static DEFINE_PER_CPU(struct local_irq_lock [NR_SOFTIRQS], local_softirq_locks); + +void __init softirq_early_init(void) +{ + int i; + + for (i = 0; i < NR_SOFTIRQS; i++) + local_irq_lock_init(local_softirq_locks[i]); +} + +static void lock_softirq(int which) +{ + local_lock(local_softirq_locks[which]); +} + +static void unlock_softirq(int which) +{ + local_unlock(local_softirq_locks[which]); +} + +static void do_single_softirq(int which, int need_rcu_bh_qs) +{ + unsigned long old_flags = current->flags; + + current->flags &= ~PF_MEMALLOC; + vtime_account_irq_enter(current); + current->flags |= PF_IN_SOFTIRQ; + lockdep_softirq_enter(); + local_irq_enable(); + handle_softirq(which); + local_irq_disable(); + lockdep_softirq_exit(); + current->flags &= ~PF_IN_SOFTIRQ; + vtime_account_irq_enter(current); + tsk_restore_flags(current, old_flags, PF_MEMALLOC); +} + +/* + * Called with interrupts disabled. Process softirqs which were raised + * in current context (or on behalf of ksoftirqd). + */ +static void do_current_softirqs(int need_rcu_bh_qs) +{ + while (current->softirqs_raised) { + int i = __ffs(current->softirqs_raised); + unsigned int pending, mask = (1U << i); + + current->softirqs_raised &= ~mask; + local_irq_enable(); + + /* + * If the lock is contended, we boost the owner to + * process the softirq or leave the critical section + * now. + */ + lock_softirq(i); + local_irq_disable(); + softirq_set_runner(i); + /* + * Check with the local_softirq_pending() bits, + * whether we need to process this still or if someone + * else took care of it. + */ + pending = local_softirq_pending(); + if (pending & mask) { + set_softirq_pending(pending & ~mask); + do_single_softirq(i, need_rcu_bh_qs); + } + softirq_clr_runner(i); + unlock_softirq(i); + WARN_ON(current->softirq_nestcnt != 1); + } +} + +static void __local_bh_disable(void) +{ + if (++current->softirq_nestcnt == 1) + migrate_disable(); +} + +void local_bh_disable(void) +{ + __local_bh_disable(); +} +EXPORT_SYMBOL(local_bh_disable); + +void __local_bh_disable_ip(unsigned long ip, unsigned int cnt) +{ + __local_bh_disable(); + if (cnt & PREEMPT_CHECK_OFFSET) + preempt_disable(); +} + +static void __local_bh_enable(void) +{ + if (WARN_ON(current->softirq_nestcnt == 0)) + return; + + local_irq_disable(); + if (current->softirq_nestcnt == 1 && current->softirqs_raised) + do_current_softirqs(1); + local_irq_enable(); + + if (--current->softirq_nestcnt == 0) + migrate_enable(); +} + +void local_bh_enable(void) +{ + __local_bh_enable(); +} +EXPORT_SYMBOL(local_bh_enable); + +extern void __local_bh_enable_ip(unsigned long ip, unsigned int cnt) +{ + __local_bh_enable(); + if (cnt & PREEMPT_CHECK_OFFSET) + preempt_enable(); +} + +void local_bh_enable_ip(unsigned long ip) +{ + local_bh_enable(); +} +EXPORT_SYMBOL(local_bh_enable_ip); + +void _local_bh_enable(void) +{ + if (WARN_ON(current->softirq_nestcnt == 0)) + return; + if (--current->softirq_nestcnt == 0) + migrate_enable(); +} +EXPORT_SYMBOL(_local_bh_enable); + +int in_serving_softirq(void) +{ + return current->flags & PF_IN_SOFTIRQ; +} +EXPORT_SYMBOL(in_serving_softirq); + +/* Called with preemption disabled */ +static void run_ksoftirqd(unsigned int cpu) +{ + local_irq_disable(); + current->softirq_nestcnt++; + + do_current_softirqs(1); + current->softirq_nestcnt--; + rcu_note_context_switch(cpu); + local_irq_enable(); +} + +/* + * Called from netif_rx_ni(). Preemption enabled, but migration + * disabled. So the cpu can't go away under us. + */ +void thread_do_softirq(void) +{ + if (!in_serving_softirq() && current->softirqs_raised) { + current->softirq_nestcnt++; + do_current_softirqs(0); + current->softirq_nestcnt--; + } +} + +static void do_raise_softirq_irqoff(unsigned int nr) +{ + trace_softirq_raise(nr); + or_softirq_pending(1UL << nr); + + /* + * If we are not in a hard interrupt and inside a bh disabled + * region, we simply raise the flag on current. local_bh_enable() + * will make sure that the softirq is executed. Otherwise we + * delegate it to ksoftirqd. + */ + if (!in_irq() && current->softirq_nestcnt) + current->softirqs_raised |= (1U << nr); + else if (__this_cpu_read(ksoftirqd)) + __this_cpu_read(ksoftirqd)->softirqs_raised |= (1U << nr); +} + +void __raise_softirq_irqoff(unsigned int nr) +{ + do_raise_softirq_irqoff(nr); + if (!in_irq() && !current->softirq_nestcnt) + wakeup_softirqd(); +} + +/* + * This function must run with irqs disabled! + */ +void raise_softirq_irqoff(unsigned int nr) +{ + do_raise_softirq_irqoff(nr); + + /* + * If we're in an hard interrupt we let irq return code deal + * with the wakeup of ksoftirqd. + */ + if (in_irq()) + return; + /* + * If we are in thread context but outside of a bh disabled + * region, we need to wake ksoftirqd as well. + * + * CHECKME: Some of the places which do that could be wrapped + * into local_bh_disable/enable pairs. Though it's unclear + * whether this is worth the effort. To find those places just + * raise a WARN() if the condition is met. + */ + if (!current->softirq_nestcnt) + wakeup_softirqd(); +} + +static inline int ksoftirqd_softirq_pending(void) +{ + return current->softirqs_raised; +} + +static inline void local_bh_disable_nort(void) { } +static inline void _local_bh_enable_nort(void) { } + +static inline void ksoftirqd_set_sched_params(unsigned int cpu) +{ + struct sched_param param = { .sched_priority = 1 }; + + sched_setscheduler(current, SCHED_FIFO, ¶m); + /* Take over all pending softirqs when starting */ + local_irq_disable(); + current->softirqs_raised = local_softirq_pending(); + local_irq_enable(); +} + +static inline void ksoftirqd_clr_sched_params(unsigned int cpu, bool online) +{ + struct sched_param param = { .sched_priority = 0 }; + + sched_setscheduler(current, SCHED_NORMAL, ¶m); +} + +#endif /* PREEMPT_RT_FULL */ +/* * Enter an interrupt context. */ void irq_enter(void) @@ -326,9 +732,9 @@ * Prevent raise_softirq from needlessly waking up ksoftirqd * here, as softirq will be serviced on return from interrupt. */ - local_bh_disable(); + local_bh_disable_nort(); tick_irq_enter(); - _local_bh_enable(); + _local_bh_enable_nort(); } __irq_enter(); @@ -336,6 +742,7 @@ static inline void invoke_softirq(void) { +#ifndef CONFIG_PREEMPT_RT_FULL if (!force_irqthreads) { #ifdef CONFIG_HAVE_IRQ_EXIT_ON_IRQ_STACK /* @@ -355,6 +762,15 @@ } else { wakeup_softirqd(); } +#else /* PREEMPT_RT_FULL */ + unsigned long flags; + + local_irq_save(flags); + if (__this_cpu_read(ksoftirqd) && + __this_cpu_read(ksoftirqd)->softirqs_raised) + wakeup_softirqd(); + local_irq_restore(flags); +#endif } static inline void tick_irq_exit(void) @@ -391,26 +807,6 @@ trace_hardirq_exit(); /* must be last! */ } -/* - * This function must run with irqs disabled! - */ -inline void raise_softirq_irqoff(unsigned int nr) -{ - __raise_softirq_irqoff(nr); - - /* - * If we're in an interrupt or softirq, we're done - * (this also catches softirq-disabled code). We will - * actually run the softirq once we return from - * the irq or softirq. - * - * Otherwise we wake up ksoftirqd to make sure we - * schedule the softirq soon. - */ - if (!in_interrupt()) - wakeup_softirqd(); -} - void raise_softirq(unsigned int nr) { unsigned long flags; @@ -420,12 +816,6 @@ local_irq_restore(flags); } -void __raise_softirq_irqoff(unsigned int nr) -{ - trace_softirq_raise(nr); - or_softirq_pending(1UL << nr); -} - void open_softirq(int nr, void (*action)(struct softirq_action *)) { softirq_vec[nr].action = action; @@ -442,15 +832,45 @@ static DEFINE_PER_CPU(struct tasklet_head, tasklet_vec); static DEFINE_PER_CPU(struct tasklet_head, tasklet_hi_vec); +static void inline +__tasklet_common_schedule(struct tasklet_struct *t, struct tasklet_head *head, unsigned int nr) +{ + if (tasklet_trylock(t)) { +again: + /* We may have been preempted before tasklet_trylock + * and __tasklet_action may have already run. + * So double check the sched bit while the takslet + * is locked before adding it to the list. + */ + if (test_bit(TASKLET_STATE_SCHED, &t->state)) { + t->next = NULL; + *head->tail = t; + head->tail = &(t->next); + raise_softirq_irqoff(nr); + tasklet_unlock(t); + } else { + /* This is subtle. If we hit the corner case above + * It is possible that we get preempted right here, + * and another task has successfully called + * tasklet_schedule(), then this function, and + * failed on the trylock. Thus we must be sure + * before releasing the tasklet lock, that the + * SCHED_BIT is clear. Otherwise the tasklet + * may get its SCHED_BIT set, but not added to the + * list + */ + if (!tasklet_tryunlock(t)) + goto again; + } + } +} + void __tasklet_schedule(struct tasklet_struct *t) { unsigned long flags; local_irq_save(flags); - t->next = NULL; - *__this_cpu_read(tasklet_vec.tail) = t; - __this_cpu_write(tasklet_vec.tail, &(t->next)); - raise_softirq_irqoff(TASKLET_SOFTIRQ); + __tasklet_common_schedule(t, &__get_cpu_var(tasklet_vec), TASKLET_SOFTIRQ); local_irq_restore(flags); } EXPORT_SYMBOL(__tasklet_schedule); @@ -460,10 +880,7 @@ unsigned long flags; local_irq_save(flags); - t->next = NULL; - *__this_cpu_read(tasklet_hi_vec.tail) = t; - __this_cpu_write(tasklet_hi_vec.tail, &(t->next)); - raise_softirq_irqoff(HI_SOFTIRQ); + __tasklet_common_schedule(t, &__get_cpu_var(tasklet_hi_vec), HI_SOFTIRQ); local_irq_restore(flags); } EXPORT_SYMBOL(__tasklet_hi_schedule); @@ -472,48 +889,116 @@ { BUG_ON(!irqs_disabled()); - t->next = __this_cpu_read(tasklet_hi_vec.head); - __this_cpu_write(tasklet_hi_vec.head, t); - __raise_softirq_irqoff(HI_SOFTIRQ); + __tasklet_hi_schedule(t); } EXPORT_SYMBOL(__tasklet_hi_schedule_first); -static void tasklet_action(struct softirq_action *a) +void tasklet_enable(struct tasklet_struct *t) { - struct tasklet_struct *list; + if (!atomic_dec_and_test(&t->count)) + return; + if (test_and_clear_bit(TASKLET_STATE_PENDING, &t->state)) + tasklet_schedule(t); +} +EXPORT_SYMBOL(tasklet_enable); - local_irq_disable(); - list = __this_cpu_read(tasklet_vec.head); - __this_cpu_write(tasklet_vec.head, NULL); - __this_cpu_write(tasklet_vec.tail, this_cpu_ptr(&tasklet_vec.head)); - local_irq_enable(); +void tasklet_hi_enable(struct tasklet_struct *t) +{ + if (!atomic_dec_and_test(&t->count)) + return; + if (test_and_clear_bit(TASKLET_STATE_PENDING, &t->state)) + tasklet_hi_schedule(t); +} +EXPORT_SYMBOL(tasklet_hi_enable); + +static void __tasklet_action(struct softirq_action *a, + struct tasklet_struct *list) +{ + int loops = 1000000; while (list) { struct tasklet_struct *t = list; list = list->next; - if (tasklet_trylock(t)) { - if (!atomic_read(&t->count)) { - if (!test_and_clear_bit(TASKLET_STATE_SCHED, - &t->state)) - BUG(); - t->func(t->data); - tasklet_unlock(t); - continue; - } - tasklet_unlock(t); + /* + * Should always succeed - after a tasklist got on the + * list (after getting the SCHED bit set from 0 to 1), + * nothing but the tasklet softirq it got queued to can + * lock it: + */ + if (!tasklet_trylock(t)) { + WARN_ON(1); + continue; } - local_irq_disable(); t->next = NULL; - *__this_cpu_read(tasklet_vec.tail) = t; - __this_cpu_write(tasklet_vec.tail, &(t->next)); - __raise_softirq_irqoff(TASKLET_SOFTIRQ); - local_irq_enable(); + + /* + * If we cannot handle the tasklet because it's disabled, + * mark it as pending. tasklet_enable() will later + * re-schedule the tasklet. + */ + if (unlikely(atomic_read(&t->count))) { +out_disabled: + /* implicit unlock: */ + wmb(); + t->state = TASKLET_STATEF_PENDING; + continue; + } + + /* + * After this point on the tasklet might be rescheduled + * on another CPU, but it can only be added to another + * CPU's tasklet list if we unlock the tasklet (which we + * dont do yet). + */ + if (!test_and_clear_bit(TASKLET_STATE_SCHED, &t->state)) + WARN_ON(1); + +again: + t->func(t->data); + + /* + * Try to unlock the tasklet. We must use cmpxchg, because + * another CPU might have scheduled or disabled the tasklet. + * We only allow the STATE_RUN -> 0 transition here. + */ + while (!tasklet_tryunlock(t)) { + /* + * If it got disabled meanwhile, bail out: + */ + if (atomic_read(&t->count)) + goto out_disabled; + /* + * If it got scheduled meanwhile, re-execute + * the tasklet function: + */ + if (test_and_clear_bit(TASKLET_STATE_SCHED, &t->state)) + goto again; + if (!--loops) { + printk("hm, tasklet state: %08lx\n", t->state); + WARN_ON(1); + tasklet_unlock(t); + break; + } + } } } +static void tasklet_action(struct softirq_action *a) +{ + struct tasklet_struct *list; + + local_irq_disable(); + list = __get_cpu_var(tasklet_vec).head; + __get_cpu_var(tasklet_vec).head = NULL; + __get_cpu_var(tasklet_vec).tail = &__get_cpu_var(tasklet_vec).head; + local_irq_enable(); + + __tasklet_action(a, list); +} + static void tasklet_hi_action(struct softirq_action *a) { struct tasklet_struct *list; @@ -524,30 +1009,7 @@ __this_cpu_write(tasklet_hi_vec.tail, this_cpu_ptr(&tasklet_hi_vec.head)); local_irq_enable(); - while (list) { - struct tasklet_struct *t = list; - - list = list->next; - - if (tasklet_trylock(t)) { - if (!atomic_read(&t->count)) { - if (!test_and_clear_bit(TASKLET_STATE_SCHED, - &t->state)) - BUG(); - t->func(t->data); - tasklet_unlock(t); - continue; - } - tasklet_unlock(t); - } - - local_irq_disable(); - t->next = NULL; - *__this_cpu_read(tasklet_hi_vec.tail) = t; - __this_cpu_write(tasklet_hi_vec.tail, &(t->next)); - __raise_softirq_irqoff(HI_SOFTIRQ); - local_irq_enable(); - } + __tasklet_action(a, list); } void tasklet_init(struct tasklet_struct *t, @@ -568,7 +1030,7 @@ while (test_and_set_bit(TASKLET_STATE_SCHED, &t->state)) { do { - yield(); + msleep(1); } while (test_bit(TASKLET_STATE_SCHED, &t->state)); } tasklet_unlock_wait(t); @@ -642,26 +1104,26 @@ open_softirq(HI_SOFTIRQ, tasklet_hi_action); } -static int ksoftirqd_should_run(unsigned int cpu) -{ - return local_softirq_pending(); -} - -static void run_ksoftirqd(unsigned int cpu) +#if defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT_FULL) +void tasklet_unlock_wait(struct tasklet_struct *t) { - local_irq_disable(); - if (local_softirq_pending()) { + while (test_bit(TASKLET_STATE_RUN, &(t)->state)) { /* - * We can safely run softirq on inline stack, as we are not deep - * in the task stack here. + * Hack for now to avoid this busy-loop: */ - __do_softirq(); - rcu_note_context_switch(cpu); - local_irq_enable(); - cond_resched(); - return; +#ifdef CONFIG_PREEMPT_RT_FULL + msleep(1); +#else + barrier(); +#endif } - local_irq_enable(); +} +EXPORT_SYMBOL(tasklet_unlock_wait); +#endif + +static int ksoftirqd_should_run(unsigned int cpu) +{ + return ksoftirqd_softirq_pending(); } #ifdef CONFIG_HOTPLUG_CPU @@ -743,6 +1205,8 @@ static struct smp_hotplug_thread softirq_threads = { .store = &ksoftirqd, + .setup = ksoftirqd_set_sched_params, + .cleanup = ksoftirqd_clr_sched_params, .thread_should_run = ksoftirqd_should_run, .thread_fn = run_ksoftirqd, .thread_comm = "ksoftirqd/%u", diff -Nur linux-3.18.14.orig/kernel/stop_machine.c linux-3.18.14-rt/kernel/stop_machine.c --- linux-3.18.14.orig/kernel/stop_machine.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/stop_machine.c 2015-05-31 15:32:48.925635362 -0500 @@ -30,12 +30,12 @@ atomic_t nr_todo; /* nr left to execute */ bool executed; /* actually executed? */ int ret; /* collected return value */ - struct completion completion; /* fired if nr_todo reaches 0 */ + struct task_struct *waiter; /* woken when nr_todo reaches 0 */ }; /* the actual stopper, one per every possible cpu, enabled on online cpus */ struct cpu_stopper { - spinlock_t lock; + raw_spinlock_t lock; bool enabled; /* is this stopper enabled? */ struct list_head works; /* list of pending works */ }; @@ -56,7 +56,7 @@ { memset(done, 0, sizeof(*done)); atomic_set(&done->nr_todo, nr_todo); - init_completion(&done->completion); + done->waiter = current; } /* signal completion unless @done is NULL */ @@ -65,8 +65,10 @@ if (done) { if (executed) done->executed = true; - if (atomic_dec_and_test(&done->nr_todo)) - complete(&done->completion); + if (atomic_dec_and_test(&done->nr_todo)) { + wake_up_process(done->waiter); + done->waiter = NULL; + } } } @@ -78,7 +80,7 @@ unsigned long flags; - spin_lock_irqsave(&stopper->lock, flags); + raw_spin_lock_irqsave(&stopper->lock, flags); if (stopper->enabled) { list_add_tail(&work->list, &stopper->works); @@ -86,7 +88,23 @@ } else cpu_stop_signal_done(work->done, false); - spin_unlock_irqrestore(&stopper->lock, flags); + raw_spin_unlock_irqrestore(&stopper->lock, flags); +} + +static void wait_for_stop_done(struct cpu_stop_done *done) +{ + set_current_state(TASK_UNINTERRUPTIBLE); + while (atomic_read(&done->nr_todo)) { + schedule(); + set_current_state(TASK_UNINTERRUPTIBLE); + } + /* + * We need to wait until cpu_stop_signal_done() has cleared + * done->waiter. + */ + while (done->waiter) + cpu_relax(); + set_current_state(TASK_RUNNING); } /** @@ -120,7 +138,7 @@ cpu_stop_init_done(&done, 1); cpu_stop_queue_work(cpu, &work); - wait_for_completion(&done.completion); + wait_for_stop_done(&done); return done.executed ? done.ret : -ENOENT; } @@ -248,7 +266,7 @@ struct irq_cpu_stop_queue_work_info call_args; struct multi_stop_data msdata; - preempt_disable(); + preempt_disable_nort(); msdata = (struct multi_stop_data){ .fn = fn, .data = arg, @@ -281,7 +299,7 @@ * This relies on the stopper workqueues to be FIFO. */ if (!cpu_active(cpu1) || !cpu_active(cpu2)) { - preempt_enable(); + preempt_enable_nort(); return -ENOENT; } @@ -295,9 +313,9 @@ &irq_cpu_stop_queue_work, &call_args, 1); lg_local_unlock(&stop_cpus_lock); - preempt_enable(); + preempt_enable_nort(); - wait_for_completion(&done.completion); + wait_for_stop_done(&done); return done.executed ? done.ret : -ENOENT; } @@ -329,7 +347,7 @@ static void queue_stop_cpus_work(const struct cpumask *cpumask, cpu_stop_fn_t fn, void *arg, - struct cpu_stop_done *done) + struct cpu_stop_done *done, bool inactive) { struct cpu_stop_work *work; unsigned int cpu; @@ -343,11 +361,13 @@ } /* - * Disable preemption while queueing to avoid getting - * preempted by a stopper which might wait for other stoppers - * to enter @fn which can lead to deadlock. + * Make sure that all work is queued on all cpus before + * any of the cpus can execute it. */ - lg_global_lock(&stop_cpus_lock); + if (!inactive) + lg_global_lock(&stop_cpus_lock); + else + lg_global_trylock_relax(&stop_cpus_lock); for_each_cpu(cpu, cpumask) cpu_stop_queue_work(cpu, &per_cpu(stop_cpus_work, cpu)); lg_global_unlock(&stop_cpus_lock); @@ -359,8 +379,8 @@ struct cpu_stop_done done; cpu_stop_init_done(&done, cpumask_weight(cpumask)); - queue_stop_cpus_work(cpumask, fn, arg, &done); - wait_for_completion(&done.completion); + queue_stop_cpus_work(cpumask, fn, arg, &done, false); + wait_for_stop_done(&done); return done.executed ? done.ret : -ENOENT; } @@ -439,9 +459,9 @@ unsigned long flags; int run; - spin_lock_irqsave(&stopper->lock, flags); + raw_spin_lock_irqsave(&stopper->lock, flags); run = !list_empty(&stopper->works); - spin_unlock_irqrestore(&stopper->lock, flags); + raw_spin_unlock_irqrestore(&stopper->lock, flags); return run; } @@ -453,13 +473,13 @@ repeat: work = NULL; - spin_lock_irq(&stopper->lock); + raw_spin_lock_irq(&stopper->lock); if (!list_empty(&stopper->works)) { work = list_first_entry(&stopper->works, struct cpu_stop_work, list); list_del_init(&work->list); } - spin_unlock_irq(&stopper->lock); + raw_spin_unlock_irq(&stopper->lock); if (work) { cpu_stop_fn_t fn = work->fn; @@ -467,6 +487,16 @@ struct cpu_stop_done *done = work->done; char ksym_buf[KSYM_NAME_LEN] __maybe_unused; + /* + * Wait until the stopper finished scheduling on all + * cpus + */ + lg_global_lock(&stop_cpus_lock); + /* + * Let other cpu threads continue as well + */ + lg_global_unlock(&stop_cpus_lock); + /* cpu stop callbacks are not allowed to sleep */ preempt_disable(); @@ -481,7 +511,13 @@ kallsyms_lookup((unsigned long)fn, NULL, NULL, NULL, ksym_buf), arg); + /* + * Make sure that the wakeup and setting done->waiter + * to NULL is atomic. + */ + local_irq_disable(); cpu_stop_signal_done(done, true); + local_irq_enable(); goto repeat; } } @@ -500,20 +536,20 @@ unsigned long flags; /* drain remaining works */ - spin_lock_irqsave(&stopper->lock, flags); + raw_spin_lock_irqsave(&stopper->lock, flags); list_for_each_entry(work, &stopper->works, list) cpu_stop_signal_done(work->done, false); stopper->enabled = false; - spin_unlock_irqrestore(&stopper->lock, flags); + raw_spin_unlock_irqrestore(&stopper->lock, flags); } static void cpu_stop_unpark(unsigned int cpu) { struct cpu_stopper *stopper = &per_cpu(cpu_stopper, cpu); - spin_lock_irq(&stopper->lock); + raw_spin_lock_irq(&stopper->lock); stopper->enabled = true; - spin_unlock_irq(&stopper->lock); + raw_spin_unlock_irq(&stopper->lock); } static struct smp_hotplug_thread cpu_stop_threads = { @@ -535,10 +571,12 @@ for_each_possible_cpu(cpu) { struct cpu_stopper *stopper = &per_cpu(cpu_stopper, cpu); - spin_lock_init(&stopper->lock); + raw_spin_lock_init(&stopper->lock); INIT_LIST_HEAD(&stopper->works); } + lg_lock_init(&stop_cpus_lock, "stop_cpus_lock"); + BUG_ON(smpboot_register_percpu_thread(&cpu_stop_threads)); stop_machine_initialized = true; return 0; @@ -634,11 +672,11 @@ set_state(&msdata, MULTI_STOP_PREPARE); cpu_stop_init_done(&done, num_active_cpus()); queue_stop_cpus_work(cpu_active_mask, multi_cpu_stop, &msdata, - &done); + &done, true); ret = multi_cpu_stop(&msdata); /* Busy wait for completion. */ - while (!completion_done(&done.completion)) + while (atomic_read(&done.nr_todo)) cpu_relax(); mutex_unlock(&stop_cpus_mutex); diff -Nur linux-3.18.14.orig/kernel/time/hrtimer.c linux-3.18.14-rt/kernel/time/hrtimer.c --- linux-3.18.14.orig/kernel/time/hrtimer.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/time/hrtimer.c 2015-05-31 15:32:48.925635362 -0500 @@ -48,11 +48,13 @@ #include #include #include +#include #include #include #include +#include #include "timekeeping.h" @@ -568,8 +570,7 @@ * When the callback is running, we do not reprogram the clock event * device. The timer callback is either running on a different CPU or * the callback is executed in the hrtimer_interrupt context. The - * reprogramming is handled either by the softirq, which called the - * callback or at the end of the hrtimer_interrupt. + * reprogramming is handled at the end of the hrtimer_interrupt. */ if (hrtimer_callback_running(timer)) return 0; @@ -604,6 +605,9 @@ return res; } +static void __run_hrtimer(struct hrtimer *timer, ktime_t *now); +static int hrtimer_rt_defer(struct hrtimer *timer); + /* * Initialize the high resolution related parts of cpu_base */ @@ -613,6 +617,21 @@ base->hres_active = 0; } +static inline int hrtimer_enqueue_reprogram(struct hrtimer *timer, + struct hrtimer_clock_base *base, + int wakeup) +{ + if (!hrtimer_reprogram(timer, base)) + return 0; + if (!wakeup) + return -ETIME; +#ifdef CONFIG_PREEMPT_RT_BASE + if (!hrtimer_rt_defer(timer)) + return -ETIME; +#endif + return 1; +} + static inline ktime_t hrtimer_update_base(struct hrtimer_cpu_base *base) { ktime_t *offs_real = &base->clock_base[HRTIMER_BASE_REALTIME].offset; @@ -678,6 +697,44 @@ static DECLARE_WORK(hrtimer_work, clock_was_set_work); +#ifdef CONFIG_PREEMPT_RT_FULL +/* + * RT can not call schedule_work from real interrupt context. + * Need to make a thread to do the real work. + */ +static struct task_struct *clock_set_delay_thread; +static bool do_clock_set_delay; + +static int run_clock_set_delay(void *ignore) +{ + while (!kthread_should_stop()) { + set_current_state(TASK_INTERRUPTIBLE); + if (do_clock_set_delay) { + do_clock_set_delay = false; + schedule_work(&hrtimer_work); + } + schedule(); + } + __set_current_state(TASK_RUNNING); + return 0; +} + +void clock_was_set_delayed(void) +{ + do_clock_set_delay = true; + /* Make visible before waking up process */ + smp_wmb(); + wake_up_process(clock_set_delay_thread); +} + +static __init int create_clock_set_delay_thread(void) +{ + clock_set_delay_thread = kthread_run(run_clock_set_delay, NULL, "kclksetdelayd"); + BUG_ON(!clock_set_delay_thread); + return 0; +} +early_initcall(create_clock_set_delay_thread); +#else /* PREEMPT_RT_FULL */ /* * Called from timekeeping and resume code to reprogramm the hrtimer * interrupt device on all cpus. @@ -686,6 +743,7 @@ { schedule_work(&hrtimer_work); } +#endif #else @@ -694,6 +752,13 @@ static inline int hrtimer_switch_to_hres(void) { return 0; } static inline void hrtimer_force_reprogram(struct hrtimer_cpu_base *base, int skip_equal) { } +static inline int hrtimer_enqueue_reprogram(struct hrtimer *timer, + struct hrtimer_clock_base *base, + int wakeup) +{ + return 0; +} + static inline int hrtimer_reprogram(struct hrtimer *timer, struct hrtimer_clock_base *base) { @@ -701,7 +766,6 @@ } static inline void hrtimer_init_hres(struct hrtimer_cpu_base *base) { } static inline void retrigger_next_event(void *arg) { } - #endif /* CONFIG_HIGH_RES_TIMERS */ /* @@ -819,6 +883,32 @@ } EXPORT_SYMBOL_GPL(hrtimer_forward); +#ifdef CONFIG_PREEMPT_RT_BASE +# define wake_up_timer_waiters(b) wake_up(&(b)->wait) + +/** + * hrtimer_wait_for_timer - Wait for a running timer + * + * @timer: timer to wait for + * + * The function waits in case the timers callback function is + * currently executed on the waitqueue of the timer base. The + * waitqueue is woken up after the timer callback function has + * finished execution. + */ +void hrtimer_wait_for_timer(const struct hrtimer *timer) +{ + struct hrtimer_clock_base *base = timer->base; + + if (base && base->cpu_base && !timer->irqsafe) + wait_event(base->cpu_base->wait, + !(timer->state & HRTIMER_STATE_CALLBACK)); +} + +#else +# define wake_up_timer_waiters(b) do { } while (0) +#endif + /* * enqueue_hrtimer - internal function to (re)start a timer * @@ -862,6 +952,11 @@ if (!(timer->state & HRTIMER_STATE_ENQUEUED)) goto out; + if (unlikely(!list_empty(&timer->cb_entry))) { + list_del_init(&timer->cb_entry); + goto out; + } + next_timer = timerqueue_getnext(&base->active); timerqueue_del(&base->active, &timer->node); if (&timer->node == next_timer) { @@ -949,7 +1044,16 @@ new_base = switch_hrtimer_base(timer, base, mode & HRTIMER_MODE_PINNED); timer_stats_hrtimer_set_start_info(timer); +#ifdef CONFIG_MISSED_TIMER_OFFSETS_HIST + { + ktime_t now = new_base->get_time(); + if (ktime_to_ns(tim) < ktime_to_ns(now)) + timer->praecox = now; + else + timer->praecox = ktime_set(0, 0); + } +#endif leftmost = enqueue_hrtimer(timer, new_base); if (!leftmost) { @@ -963,15 +1067,26 @@ * on dynticks target. */ wake_up_nohz_cpu(new_base->cpu_base->cpu); - } else if (new_base->cpu_base == this_cpu_ptr(&hrtimer_bases) && - hrtimer_reprogram(timer, new_base)) { + } else if (new_base->cpu_base == this_cpu_ptr(&hrtimer_bases)) { + + ret = hrtimer_enqueue_reprogram(timer, new_base, wakeup); + if (ret < 0) { + /* + * In case we failed to reprogram the timer (mostly + * because out current timer is already elapsed), + * remove it again and report a failure. This avoids + * stale base->first entries. + */ + debug_deactivate(timer); + __remove_hrtimer(timer, new_base, + timer->state & HRTIMER_STATE_CALLBACK, 0); + } else if (ret > 0) { /* * Only allow reprogramming if the new base is on this CPU. * (it might still be on another CPU if the timer was pending) * * XXX send_remote_softirq() ? */ - if (wakeup) { /* * We need to drop cpu_base->lock to avoid a * lock ordering issue vs. rq->lock. @@ -979,9 +1094,7 @@ raw_spin_unlock(&new_base->cpu_base->lock); raise_softirq_irqoff(HRTIMER_SOFTIRQ); local_irq_restore(flags); - return ret; - } else { - __raise_softirq_irqoff(HRTIMER_SOFTIRQ); + return 0; } } @@ -1072,7 +1185,7 @@ if (ret >= 0) return ret; - cpu_relax(); + hrtimer_wait_for_timer(timer); } } EXPORT_SYMBOL_GPL(hrtimer_cancel); @@ -1151,6 +1264,7 @@ base = hrtimer_clockid_to_base(clock_id); timer->base = &cpu_base->clock_base[base]; + INIT_LIST_HEAD(&timer->cb_entry); timerqueue_init(&timer->node); #ifdef CONFIG_TIMER_STATS @@ -1234,6 +1348,126 @@ timer->state &= ~HRTIMER_STATE_CALLBACK; } +static enum hrtimer_restart hrtimer_wakeup(struct hrtimer *timer); + +#ifdef CONFIG_PREEMPT_RT_BASE +static void hrtimer_rt_reprogram(int restart, struct hrtimer *timer, + struct hrtimer_clock_base *base) +{ + /* + * Note, we clear the callback flag before we requeue the + * timer otherwise we trigger the callback_running() check + * in hrtimer_reprogram(). + */ + timer->state &= ~HRTIMER_STATE_CALLBACK; + + if (restart != HRTIMER_NORESTART) { + BUG_ON(hrtimer_active(timer)); + /* + * Enqueue the timer, if it's the leftmost timer then + * we need to reprogram it. + */ + if (!enqueue_hrtimer(timer, base)) + return; + +#ifndef CONFIG_HIGH_RES_TIMERS + } +#else + if (base->cpu_base->hres_active && + hrtimer_reprogram(timer, base)) + goto requeue; + + } else if (hrtimer_active(timer)) { + /* + * If the timer was rearmed on another CPU, reprogram + * the event device. + */ + if (&timer->node == base->active.next && + base->cpu_base->hres_active && + hrtimer_reprogram(timer, base)) + goto requeue; + } + return; + +requeue: + /* + * Timer is expired. Thus move it from tree to pending list + * again. + */ + __remove_hrtimer(timer, base, timer->state, 0); + list_add_tail(&timer->cb_entry, &base->expired); +#endif +} + +/* + * The changes in mainline which removed the callback modes from + * hrtimer are not yet working with -rt. The non wakeup_process() + * based callbacks which involve sleeping locks need to be treated + * seperately. + */ +static void hrtimer_rt_run_pending(void) +{ + enum hrtimer_restart (*fn)(struct hrtimer *); + struct hrtimer_cpu_base *cpu_base; + struct hrtimer_clock_base *base; + struct hrtimer *timer; + int index, restart; + + local_irq_disable(); + cpu_base = &per_cpu(hrtimer_bases, smp_processor_id()); + + raw_spin_lock(&cpu_base->lock); + + for (index = 0; index < HRTIMER_MAX_CLOCK_BASES; index++) { + base = &cpu_base->clock_base[index]; + + while (!list_empty(&base->expired)) { + timer = list_first_entry(&base->expired, + struct hrtimer, cb_entry); + + /* + * Same as the above __run_hrtimer function + * just we run with interrupts enabled. + */ + debug_hrtimer_deactivate(timer); + __remove_hrtimer(timer, base, HRTIMER_STATE_CALLBACK, 0); + timer_stats_account_hrtimer(timer); + fn = timer->function; + + raw_spin_unlock_irq(&cpu_base->lock); + restart = fn(timer); + raw_spin_lock_irq(&cpu_base->lock); + + hrtimer_rt_reprogram(restart, timer, base); + } + } + + raw_spin_unlock_irq(&cpu_base->lock); + + wake_up_timer_waiters(cpu_base); +} + +static int hrtimer_rt_defer(struct hrtimer *timer) +{ + if (timer->irqsafe) + return 0; + + __remove_hrtimer(timer, timer->base, timer->state, 0); + list_add_tail(&timer->cb_entry, &timer->base->expired); + return 1; +} + +#else + +static inline void hrtimer_rt_run_pending(void) +{ + hrtimer_peek_ahead_timers(); +} + +static inline int hrtimer_rt_defer(struct hrtimer *timer) { return 0; } + +#endif + #ifdef CONFIG_HIGH_RES_TIMERS /* @@ -1244,7 +1478,7 @@ { struct hrtimer_cpu_base *cpu_base = this_cpu_ptr(&hrtimer_bases); ktime_t expires_next, now, entry_time, delta; - int i, retries = 0; + int i, retries = 0, raise = 0; BUG_ON(!cpu_base->hres_active); cpu_base->nr_events++; @@ -1279,6 +1513,15 @@ timer = container_of(node, struct hrtimer, node); + trace_hrtimer_interrupt(raw_smp_processor_id(), + ktime_to_ns(ktime_sub(ktime_to_ns(timer->praecox) ? + timer->praecox : hrtimer_get_expires(timer), + basenow)), + current, + timer->function == hrtimer_wakeup ? + container_of(timer, struct hrtimer_sleeper, + timer)->task : NULL); + /* * The immediate goal for using the softexpires is * minimizing wakeups, not running timers at the @@ -1304,7 +1547,10 @@ break; } - __run_hrtimer(timer, &basenow); + if (!hrtimer_rt_defer(timer)) + __run_hrtimer(timer, &basenow); + else + raise = 1; } } @@ -1319,7 +1565,7 @@ if (expires_next.tv64 == KTIME_MAX || !tick_program_event(expires_next, 0)) { cpu_base->hang_detected = 0; - return; + goto out; } /* @@ -1363,6 +1609,9 @@ tick_program_event(expires_next, 1); printk_once(KERN_WARNING "hrtimer: interrupt took %llu ns\n", ktime_to_ns(delta)); +out: + if (raise) + raise_softirq_irqoff(HRTIMER_SOFTIRQ); } /* @@ -1398,18 +1647,18 @@ __hrtimer_peek_ahead_timers(); local_irq_restore(flags); } - -static void run_hrtimer_softirq(struct softirq_action *h) -{ - hrtimer_peek_ahead_timers(); -} - #else /* CONFIG_HIGH_RES_TIMERS */ static inline void __hrtimer_peek_ahead_timers(void) { } #endif /* !CONFIG_HIGH_RES_TIMERS */ + +static void run_hrtimer_softirq(struct softirq_action *h) +{ + hrtimer_rt_run_pending(); +} + /* * Called from timer softirq every jiffy, expire hrtimers: * @@ -1442,7 +1691,7 @@ struct timerqueue_node *node; struct hrtimer_cpu_base *cpu_base = this_cpu_ptr(&hrtimer_bases); struct hrtimer_clock_base *base; - int index, gettime = 1; + int index, gettime = 1, raise = 0; if (hrtimer_hres_active()) return; @@ -1467,10 +1716,16 @@ hrtimer_get_expires_tv64(timer)) break; - __run_hrtimer(timer, &base->softirq_time); + if (!hrtimer_rt_defer(timer)) + __run_hrtimer(timer, &base->softirq_time); + else + raise = 1; } raw_spin_unlock(&cpu_base->lock); } + + if (raise) + raise_softirq_irqoff(HRTIMER_SOFTIRQ); } /* @@ -1492,16 +1747,18 @@ void hrtimer_init_sleeper(struct hrtimer_sleeper *sl, struct task_struct *task) { sl->timer.function = hrtimer_wakeup; + sl->timer.irqsafe = 1; sl->task = task; } EXPORT_SYMBOL_GPL(hrtimer_init_sleeper); -static int __sched do_nanosleep(struct hrtimer_sleeper *t, enum hrtimer_mode mode) +static int __sched do_nanosleep(struct hrtimer_sleeper *t, enum hrtimer_mode mode, + unsigned long state) { hrtimer_init_sleeper(t, current); do { - set_current_state(TASK_INTERRUPTIBLE); + set_current_state(state); hrtimer_start_expires(&t->timer, mode); if (!hrtimer_active(&t->timer)) t->task = NULL; @@ -1545,7 +1802,8 @@ HRTIMER_MODE_ABS); hrtimer_set_expires_tv64(&t.timer, restart->nanosleep.expires); - if (do_nanosleep(&t, HRTIMER_MODE_ABS)) + /* cpu_chill() does not care about restart state. */ + if (do_nanosleep(&t, HRTIMER_MODE_ABS, TASK_INTERRUPTIBLE)) goto out; rmtp = restart->nanosleep.rmtp; @@ -1562,8 +1820,10 @@ return ret; } -long hrtimer_nanosleep(struct timespec *rqtp, struct timespec __user *rmtp, - const enum hrtimer_mode mode, const clockid_t clockid) +static long +__hrtimer_nanosleep(struct timespec *rqtp, struct timespec __user *rmtp, + const enum hrtimer_mode mode, const clockid_t clockid, + unsigned long state) { struct restart_block *restart; struct hrtimer_sleeper t; @@ -1576,7 +1836,7 @@ hrtimer_init_on_stack(&t.timer, clockid, mode); hrtimer_set_expires_range_ns(&t.timer, timespec_to_ktime(*rqtp), slack); - if (do_nanosleep(&t, mode)) + if (do_nanosleep(&t, mode, state)) goto out; /* Absolute timers do not update the rmtp value and restart: */ @@ -1603,6 +1863,12 @@ return ret; } +long hrtimer_nanosleep(struct timespec *rqtp, struct timespec __user *rmtp, + const enum hrtimer_mode mode, const clockid_t clockid) +{ + return __hrtimer_nanosleep(rqtp, rmtp, mode, clockid, TASK_INTERRUPTIBLE); +} + SYSCALL_DEFINE2(nanosleep, struct timespec __user *, rqtp, struct timespec __user *, rmtp) { @@ -1617,6 +1883,26 @@ return hrtimer_nanosleep(&tu, rmtp, HRTIMER_MODE_REL, CLOCK_MONOTONIC); } +#ifdef CONFIG_PREEMPT_RT_FULL +/* + * Sleep for 1 ms in hope whoever holds what we want will let it go. + */ +void cpu_chill(void) +{ + struct timespec tu = { + .tv_nsec = NSEC_PER_MSEC, + }; + unsigned int freeze_flag = current->flags & PF_NOFREEZE; + + current->flags |= PF_NOFREEZE; + __hrtimer_nanosleep(&tu, NULL, HRTIMER_MODE_REL, CLOCK_MONOTONIC, + TASK_UNINTERRUPTIBLE); + if (!freeze_flag) + current->flags &= ~PF_NOFREEZE; +} +EXPORT_SYMBOL(cpu_chill); +#endif + /* * Functions related to boot-time initialization: */ @@ -1628,10 +1914,14 @@ for (i = 0; i < HRTIMER_MAX_CLOCK_BASES; i++) { cpu_base->clock_base[i].cpu_base = cpu_base; timerqueue_init_head(&cpu_base->clock_base[i].active); + INIT_LIST_HEAD(&cpu_base->clock_base[i].expired); } cpu_base->cpu = cpu; hrtimer_init_hres(cpu_base); +#ifdef CONFIG_PREEMPT_RT_BASE + init_waitqueue_head(&cpu_base->wait); +#endif } #ifdef CONFIG_HOTPLUG_CPU @@ -1744,9 +2034,7 @@ hrtimer_cpu_notify(&hrtimers_nb, (unsigned long)CPU_UP_PREPARE, (void *)(long)smp_processor_id()); register_cpu_notifier(&hrtimers_nb); -#ifdef CONFIG_HIGH_RES_TIMERS open_softirq(HRTIMER_SOFTIRQ, run_hrtimer_softirq); -#endif } /** diff -Nur linux-3.18.14.orig/kernel/time/itimer.c linux-3.18.14-rt/kernel/time/itimer.c --- linux-3.18.14.orig/kernel/time/itimer.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/time/itimer.c 2015-05-31 15:32:48.957635362 -0500 @@ -213,6 +213,7 @@ /* We are sharing ->siglock with it_real_fn() */ if (hrtimer_try_to_cancel(timer) < 0) { spin_unlock_irq(&tsk->sighand->siglock); + hrtimer_wait_for_timer(&tsk->signal->real_timer); goto again; } expires = timeval_to_ktime(value->it_value); diff -Nur linux-3.18.14.orig/kernel/time/jiffies.c linux-3.18.14-rt/kernel/time/jiffies.c --- linux-3.18.14.orig/kernel/time/jiffies.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/time/jiffies.c 2015-05-31 15:32:48.957635362 -0500 @@ -73,7 +73,8 @@ .shift = JIFFIES_SHIFT, }; -__cacheline_aligned_in_smp DEFINE_SEQLOCK(jiffies_lock); +__cacheline_aligned_in_smp DEFINE_RAW_SPINLOCK(jiffies_lock); +__cacheline_aligned_in_smp seqcount_t jiffies_seq; #if (BITS_PER_LONG < 64) u64 get_jiffies_64(void) @@ -82,9 +83,9 @@ u64 ret; do { - seq = read_seqbegin(&jiffies_lock); + seq = read_seqcount_begin(&jiffies_seq); ret = jiffies_64; - } while (read_seqretry(&jiffies_lock, seq)); + } while (read_seqcount_retry(&jiffies_seq, seq)); return ret; } EXPORT_SYMBOL(get_jiffies_64); diff -Nur linux-3.18.14.orig/kernel/time/ntp.c linux-3.18.14-rt/kernel/time/ntp.c --- linux-3.18.14.orig/kernel/time/ntp.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/time/ntp.c 2015-05-31 15:32:48.957635362 -0500 @@ -10,6 +10,7 @@ #include #include #include +#include #include #include #include @@ -519,10 +520,52 @@ &sync_cmos_work, timespec_to_jiffies(&next)); } +#ifdef CONFIG_PREEMPT_RT_FULL +/* + * RT can not call schedule_delayed_work from real interrupt context. + * Need to make a thread to do the real work. + */ +static struct task_struct *cmos_delay_thread; +static bool do_cmos_delay; + +static int run_cmos_delay(void *ignore) +{ + while (!kthread_should_stop()) { + set_current_state(TASK_INTERRUPTIBLE); + if (do_cmos_delay) { + do_cmos_delay = false; + queue_delayed_work(system_power_efficient_wq, + &sync_cmos_work, 0); + } + schedule(); + } + __set_current_state(TASK_RUNNING); + return 0; +} + +void ntp_notify_cmos_timer(void) +{ + do_cmos_delay = true; + /* Make visible before waking up process */ + smp_wmb(); + wake_up_process(cmos_delay_thread); +} + +static __init int create_cmos_delay_thread(void) +{ + cmos_delay_thread = kthread_run(run_cmos_delay, NULL, "kcmosdelayd"); + BUG_ON(!cmos_delay_thread); + return 0; +} +early_initcall(create_cmos_delay_thread); + +#else + void ntp_notify_cmos_timer(void) { queue_delayed_work(system_power_efficient_wq, &sync_cmos_work, 0); } +#endif /* CONFIG_PREEMPT_RT_FULL */ #else void ntp_notify_cmos_timer(void) { } diff -Nur linux-3.18.14.orig/kernel/time/posix-cpu-timers.c linux-3.18.14-rt/kernel/time/posix-cpu-timers.c --- linux-3.18.14.orig/kernel/time/posix-cpu-timers.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/time/posix-cpu-timers.c 2015-05-31 15:32:48.961635362 -0500 @@ -3,6 +3,7 @@ */ #include +#include #include #include #include @@ -626,7 +627,7 @@ /* * Disarm any old timer after extracting its expiry time. */ - WARN_ON_ONCE(!irqs_disabled()); + WARN_ON_ONCE_NONRT(!irqs_disabled()); ret = 0; old_incr = timer->it.cpu.incr; @@ -1047,7 +1048,7 @@ /* * Now re-arm for the new expiry time. */ - WARN_ON_ONCE(!irqs_disabled()); + WARN_ON_ONCE_NONRT(!irqs_disabled()); arm_timer(timer); unlock_task_sighand(p, &flags); @@ -1113,10 +1114,11 @@ sig = tsk->signal; if (sig->cputimer.running) { struct task_cputime group_sample; + unsigned long flags; - raw_spin_lock(&sig->cputimer.lock); + raw_spin_lock_irqsave(&sig->cputimer.lock, flags); group_sample = sig->cputimer.cputime; - raw_spin_unlock(&sig->cputimer.lock); + raw_spin_unlock_irqrestore(&sig->cputimer.lock, flags); if (task_cputime_expired(&group_sample, &sig->cputime_expires)) return 1; @@ -1130,13 +1132,13 @@ * already updated our counts. We need to check if any timers fire now. * Interrupts are disabled. */ -void run_posix_cpu_timers(struct task_struct *tsk) +static void __run_posix_cpu_timers(struct task_struct *tsk) { LIST_HEAD(firing); struct k_itimer *timer, *next; unsigned long flags; - WARN_ON_ONCE(!irqs_disabled()); + WARN_ON_ONCE_NONRT(!irqs_disabled()); /* * The fast path checks that there are no expired thread or thread @@ -1194,6 +1196,190 @@ } } +#ifdef CONFIG_PREEMPT_RT_BASE +#include +#include +DEFINE_PER_CPU(struct task_struct *, posix_timer_task); +DEFINE_PER_CPU(struct task_struct *, posix_timer_tasklist); + +static int posix_cpu_timers_thread(void *data) +{ + int cpu = (long)data; + + BUG_ON(per_cpu(posix_timer_task,cpu) != current); + + while (!kthread_should_stop()) { + struct task_struct *tsk = NULL; + struct task_struct *next = NULL; + + if (cpu_is_offline(cpu)) + goto wait_to_die; + + /* grab task list */ + raw_local_irq_disable(); + tsk = per_cpu(posix_timer_tasklist, cpu); + per_cpu(posix_timer_tasklist, cpu) = NULL; + raw_local_irq_enable(); + + /* its possible the list is empty, just return */ + if (!tsk) { + set_current_state(TASK_INTERRUPTIBLE); + schedule(); + __set_current_state(TASK_RUNNING); + continue; + } + + /* Process task list */ + while (1) { + /* save next */ + next = tsk->posix_timer_list; + + /* run the task timers, clear its ptr and + * unreference it + */ + __run_posix_cpu_timers(tsk); + tsk->posix_timer_list = NULL; + put_task_struct(tsk); + + /* check if this is the last on the list */ + if (next == tsk) + break; + tsk = next; + } + } + return 0; + +wait_to_die: + /* Wait for kthread_stop */ + set_current_state(TASK_INTERRUPTIBLE); + while (!kthread_should_stop()) { + schedule(); + set_current_state(TASK_INTERRUPTIBLE); + } + __set_current_state(TASK_RUNNING); + return 0; +} + +static inline int __fastpath_timer_check(struct task_struct *tsk) +{ + /* tsk == current, ensure it is safe to use ->signal/sighand */ + if (unlikely(tsk->exit_state)) + return 0; + + if (!task_cputime_zero(&tsk->cputime_expires)) + return 1; + + if (!task_cputime_zero(&tsk->signal->cputime_expires)) + return 1; + + return 0; +} + +void run_posix_cpu_timers(struct task_struct *tsk) +{ + unsigned long cpu = smp_processor_id(); + struct task_struct *tasklist; + + BUG_ON(!irqs_disabled()); + if(!per_cpu(posix_timer_task, cpu)) + return; + /* get per-cpu references */ + tasklist = per_cpu(posix_timer_tasklist, cpu); + + /* check to see if we're already queued */ + if (!tsk->posix_timer_list && __fastpath_timer_check(tsk)) { + get_task_struct(tsk); + if (tasklist) { + tsk->posix_timer_list = tasklist; + } else { + /* + * The list is terminated by a self-pointing + * task_struct + */ + tsk->posix_timer_list = tsk; + } + per_cpu(posix_timer_tasklist, cpu) = tsk; + + wake_up_process(per_cpu(posix_timer_task, cpu)); + } +} + +/* + * posix_cpu_thread_call - callback that gets triggered when a CPU is added. + * Here we can start up the necessary migration thread for the new CPU. + */ +static int posix_cpu_thread_call(struct notifier_block *nfb, + unsigned long action, void *hcpu) +{ + int cpu = (long)hcpu; + struct task_struct *p; + struct sched_param param; + + switch (action) { + case CPU_UP_PREPARE: + p = kthread_create(posix_cpu_timers_thread, hcpu, + "posixcputmr/%d",cpu); + if (IS_ERR(p)) + return NOTIFY_BAD; + p->flags |= PF_NOFREEZE; + kthread_bind(p, cpu); + /* Must be high prio to avoid getting starved */ + param.sched_priority = MAX_RT_PRIO-1; + sched_setscheduler(p, SCHED_FIFO, ¶m); + per_cpu(posix_timer_task,cpu) = p; + break; + case CPU_ONLINE: + /* Strictly unneccessary, as first user will wake it. */ + wake_up_process(per_cpu(posix_timer_task,cpu)); + break; +#ifdef CONFIG_HOTPLUG_CPU + case CPU_UP_CANCELED: + /* Unbind it from offline cpu so it can run. Fall thru. */ + kthread_bind(per_cpu(posix_timer_task, cpu), + cpumask_any(cpu_online_mask)); + kthread_stop(per_cpu(posix_timer_task,cpu)); + per_cpu(posix_timer_task,cpu) = NULL; + break; + case CPU_DEAD: + kthread_stop(per_cpu(posix_timer_task,cpu)); + per_cpu(posix_timer_task,cpu) = NULL; + break; +#endif + } + return NOTIFY_OK; +} + +/* Register at highest priority so that task migration (migrate_all_tasks) + * happens before everything else. + */ +static struct notifier_block posix_cpu_thread_notifier = { + .notifier_call = posix_cpu_thread_call, + .priority = 10 +}; + +static int __init posix_cpu_thread_init(void) +{ + void *hcpu = (void *)(long)smp_processor_id(); + /* Start one for boot CPU. */ + unsigned long cpu; + + /* init the per-cpu posix_timer_tasklets */ + for_each_possible_cpu(cpu) + per_cpu(posix_timer_tasklist, cpu) = NULL; + + posix_cpu_thread_call(&posix_cpu_thread_notifier, CPU_UP_PREPARE, hcpu); + posix_cpu_thread_call(&posix_cpu_thread_notifier, CPU_ONLINE, hcpu); + register_cpu_notifier(&posix_cpu_thread_notifier); + return 0; +} +early_initcall(posix_cpu_thread_init); +#else /* CONFIG_PREEMPT_RT_BASE */ +void run_posix_cpu_timers(struct task_struct *tsk) +{ + __run_posix_cpu_timers(tsk); +} +#endif /* CONFIG_PREEMPT_RT_BASE */ + /* * Set one of the process-wide special case CPU timers or RLIMIT_CPU. * The tsk->sighand->siglock must be held by the caller. diff -Nur linux-3.18.14.orig/kernel/time/posix-timers.c linux-3.18.14-rt/kernel/time/posix-timers.c --- linux-3.18.14.orig/kernel/time/posix-timers.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/time/posix-timers.c 2015-05-31 15:32:48.961635362 -0500 @@ -499,6 +499,7 @@ static struct pid *good_sigevent(sigevent_t * event) { struct task_struct *rtn = current->group_leader; + int sig = event->sigev_signo; if ((event->sigev_notify & SIGEV_THREAD_ID ) && (!(rtn = find_task_by_vpid(event->sigev_notify_thread_id)) || @@ -507,7 +508,8 @@ return NULL; if (((event->sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_NONE) && - ((event->sigev_signo <= 0) || (event->sigev_signo > SIGRTMAX))) + (sig <= 0 || sig > SIGRTMAX || sig_kernel_only(sig) || + sig_kernel_coredump(sig))) return NULL; return task_pid(rtn); @@ -819,6 +821,20 @@ return overrun; } +/* + * Protected by RCU! + */ +static void timer_wait_for_callback(struct k_clock *kc, struct k_itimer *timr) +{ +#ifdef CONFIG_PREEMPT_RT_FULL + if (kc->timer_set == common_timer_set) + hrtimer_wait_for_timer(&timr->it.real.timer); + else + /* FIXME: Whacky hack for posix-cpu-timers */ + schedule_timeout(1); +#endif +} + /* Set a POSIX.1b interval timer. */ /* timr->it_lock is taken. */ static int @@ -896,6 +912,7 @@ if (!timr) return -EINVAL; + rcu_read_lock(); kc = clockid_to_kclock(timr->it_clock); if (WARN_ON_ONCE(!kc || !kc->timer_set)) error = -EINVAL; @@ -904,9 +921,12 @@ unlock_timer(timr, flag); if (error == TIMER_RETRY) { + timer_wait_for_callback(kc, timr); rtn = NULL; // We already got the old time... + rcu_read_unlock(); goto retry; } + rcu_read_unlock(); if (old_setting && !error && copy_to_user(old_setting, &old_spec, sizeof (old_spec))) @@ -944,10 +964,15 @@ if (!timer) return -EINVAL; + rcu_read_lock(); if (timer_delete_hook(timer) == TIMER_RETRY) { unlock_timer(timer, flags); + timer_wait_for_callback(clockid_to_kclock(timer->it_clock), + timer); + rcu_read_unlock(); goto retry_delete; } + rcu_read_unlock(); spin_lock(¤t->sighand->siglock); list_del(&timer->list); @@ -973,8 +998,18 @@ retry_delete: spin_lock_irqsave(&timer->it_lock, flags); + /* On RT we can race with a deletion */ + if (!timer->it_signal) { + unlock_timer(timer, flags); + return; + } + if (timer_delete_hook(timer) == TIMER_RETRY) { + rcu_read_lock(); unlock_timer(timer, flags); + timer_wait_for_callback(clockid_to_kclock(timer->it_clock), + timer); + rcu_read_unlock(); goto retry_delete; } list_del(&timer->list); diff -Nur linux-3.18.14.orig/kernel/time/tick-common.c linux-3.18.14-rt/kernel/time/tick-common.c --- linux-3.18.14.orig/kernel/time/tick-common.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/time/tick-common.c 2015-05-31 15:32:48.961635362 -0500 @@ -78,13 +78,15 @@ static void tick_periodic(int cpu) { if (tick_do_timer_cpu == cpu) { - write_seqlock(&jiffies_lock); + raw_spin_lock(&jiffies_lock); + write_seqcount_begin(&jiffies_seq); /* Keep track of the next tick event */ tick_next_period = ktime_add(tick_next_period, tick_period); do_timer(1); - write_sequnlock(&jiffies_lock); + write_seqcount_end(&jiffies_seq); + raw_spin_unlock(&jiffies_lock); update_wall_time(); } @@ -146,9 +148,9 @@ ktime_t next; do { - seq = read_seqbegin(&jiffies_lock); + seq = read_seqcount_begin(&jiffies_seq); next = tick_next_period; - } while (read_seqretry(&jiffies_lock, seq)); + } while (read_seqcount_retry(&jiffies_seq, seq)); clockevents_set_mode(dev, CLOCK_EVT_MODE_ONESHOT); diff -Nur linux-3.18.14.orig/kernel/time/tick-internal.h linux-3.18.14-rt/kernel/time/tick-internal.h --- linux-3.18.14.orig/kernel/time/tick-internal.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/time/tick-internal.h 2015-05-31 15:32:48.961635362 -0500 @@ -6,7 +6,8 @@ #include "timekeeping.h" -extern seqlock_t jiffies_lock; +extern raw_spinlock_t jiffies_lock; +extern seqcount_t jiffies_seq; #define CS_NAME_LEN 32 diff -Nur linux-3.18.14.orig/kernel/time/tick-sched.c linux-3.18.14-rt/kernel/time/tick-sched.c --- linux-3.18.14.orig/kernel/time/tick-sched.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/time/tick-sched.c 2015-05-31 15:32:48.961635362 -0500 @@ -62,7 +62,8 @@ return; /* Reevalute with jiffies_lock held */ - write_seqlock(&jiffies_lock); + raw_spin_lock(&jiffies_lock); + write_seqcount_begin(&jiffies_seq); delta = ktime_sub(now, last_jiffies_update); if (delta.tv64 >= tick_period.tv64) { @@ -85,10 +86,12 @@ /* Keep the tick_next_period variable up to date */ tick_next_period = ktime_add(last_jiffies_update, tick_period); } else { - write_sequnlock(&jiffies_lock); + write_seqcount_end(&jiffies_seq); + raw_spin_unlock(&jiffies_lock); return; } - write_sequnlock(&jiffies_lock); + write_seqcount_end(&jiffies_seq); + raw_spin_unlock(&jiffies_lock); update_wall_time(); } @@ -99,12 +102,14 @@ { ktime_t period; - write_seqlock(&jiffies_lock); + raw_spin_lock(&jiffies_lock); + write_seqcount_begin(&jiffies_seq); /* Did we start the jiffies update yet ? */ if (last_jiffies_update.tv64 == 0) last_jiffies_update = tick_next_period; period = last_jiffies_update; - write_sequnlock(&jiffies_lock); + write_seqcount_end(&jiffies_seq); + raw_spin_unlock(&jiffies_lock); return period; } @@ -176,6 +181,11 @@ return false; } + if (!arch_irq_work_has_interrupt()) { + trace_tick_stop(0, "missing irq work interrupt\n"); + return false; + } + /* sched_clock_tick() needs us? */ #ifdef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK /* @@ -217,11 +227,17 @@ static void nohz_full_kick_work_func(struct irq_work *work) { + unsigned long flags; + + /* ksoftirqd processes sirqs with interrupts enabled */ + local_irq_save(flags); __tick_nohz_full_check(); + local_irq_restore(flags); } static DEFINE_PER_CPU(struct irq_work, nohz_full_kick_work) = { .func = nohz_full_kick_work_func, + .flags = IRQ_WORK_HARD_IRQ, }; /* @@ -580,10 +596,10 @@ /* Read jiffies and the time when jiffies were updated last */ do { - seq = read_seqbegin(&jiffies_lock); + seq = read_seqcount_begin(&jiffies_seq); last_update = last_jiffies_update; last_jiffies = jiffies; - } while (read_seqretry(&jiffies_lock, seq)); + } while (read_seqcount_retry(&jiffies_seq, seq)); if (rcu_needs_cpu(cpu, &rcu_delta_jiffies) || arch_needs_cpu() || irq_work_needs_cpu()) { @@ -761,14 +777,7 @@ return false; if (unlikely(local_softirq_pending() && cpu_online(cpu))) { - static int ratelimit; - - if (ratelimit < 10 && - (local_softirq_pending() & SOFTIRQ_STOP_IDLE_MASK)) { - pr_warn("NOHZ: local_softirq_pending %02x\n", - (unsigned int) local_softirq_pending()); - ratelimit++; - } + softirq_check_pending_idle(); return false; } @@ -1156,6 +1165,7 @@ * Emulate tick processing via per-CPU hrtimers: */ hrtimer_init(&ts->sched_timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS); + ts->sched_timer.irqsafe = 1; ts->sched_timer.function = tick_sched_timer; /* Get the next period (per cpu) */ diff -Nur linux-3.18.14.orig/kernel/time/timekeeping.c linux-3.18.14-rt/kernel/time/timekeeping.c --- linux-3.18.14.orig/kernel/time/timekeeping.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/time/timekeeping.c 2015-05-31 15:32:48.969635362 -0500 @@ -1814,8 +1814,10 @@ */ void xtime_update(unsigned long ticks) { - write_seqlock(&jiffies_lock); + raw_spin_lock(&jiffies_lock); + write_seqcount_begin(&jiffies_seq); do_timer(ticks); - write_sequnlock(&jiffies_lock); + write_seqcount_end(&jiffies_seq); + raw_spin_unlock(&jiffies_lock); update_wall_time(); } diff -Nur linux-3.18.14.orig/kernel/time/timer.c linux-3.18.14-rt/kernel/time/timer.c --- linux-3.18.14.orig/kernel/time/timer.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/time/timer.c 2015-05-31 15:32:48.973635362 -0500 @@ -78,6 +78,9 @@ struct tvec_base { spinlock_t lock; struct timer_list *running_timer; +#ifdef CONFIG_PREEMPT_RT_FULL + wait_queue_head_t wait_for_running_timer; +#endif unsigned long timer_jiffies; unsigned long next_timer; unsigned long active_timers; @@ -758,6 +761,36 @@ } } +#ifndef CONFIG_PREEMPT_RT_FULL +static inline struct tvec_base *switch_timer_base(struct timer_list *timer, + struct tvec_base *old, + struct tvec_base *new) +{ + /* See the comment in lock_timer_base() */ + timer_set_base(timer, NULL); + spin_unlock(&old->lock); + spin_lock(&new->lock); + timer_set_base(timer, new); + return new; +} +#else +static inline struct tvec_base *switch_timer_base(struct timer_list *timer, + struct tvec_base *old, + struct tvec_base *new) +{ + /* + * We cannot do the above because we might be preempted and + * then the preempter would see NULL and loop forever. + */ + if (spin_trylock(&new->lock)) { + timer_set_base(timer, new); + spin_unlock(&old->lock); + return new; + } + return old; +} +#endif + static inline int __mod_timer(struct timer_list *timer, unsigned long expires, bool pending_only, int pinned) @@ -788,14 +821,8 @@ * handler yet has not finished. This also guarantees that * the timer is serialized wrt itself. */ - if (likely(base->running_timer != timer)) { - /* See the comment in lock_timer_base() */ - timer_set_base(timer, NULL); - spin_unlock(&base->lock); - base = new_base; - spin_lock(&base->lock); - timer_set_base(timer, base); - } + if (likely(base->running_timer != timer)) + base = switch_timer_base(timer, base, new_base); } timer->expires = expires; @@ -969,6 +996,29 @@ } EXPORT_SYMBOL_GPL(add_timer_on); +#ifdef CONFIG_PREEMPT_RT_FULL +/* + * Wait for a running timer + */ +static void wait_for_running_timer(struct timer_list *timer) +{ + struct tvec_base *base = timer->base; + + if (base->running_timer == timer) + wait_event(base->wait_for_running_timer, + base->running_timer != timer); +} + +# define wakeup_timer_waiters(b) wake_up(&(b)->wait_for_running_timer) +#else +static inline void wait_for_running_timer(struct timer_list *timer) +{ + cpu_relax(); +} + +# define wakeup_timer_waiters(b) do { } while (0) +#endif + /** * del_timer - deactive a timer. * @timer: the timer to be deactivated @@ -1026,7 +1076,7 @@ } EXPORT_SYMBOL(try_to_del_timer_sync); -#ifdef CONFIG_SMP +#if defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT_FULL) /** * del_timer_sync - deactivate a timer and wait for the handler to finish. * @timer: the timer to be deactivated @@ -1086,7 +1136,7 @@ int ret = try_to_del_timer_sync(timer); if (ret >= 0) return ret; - cpu_relax(); + wait_for_running_timer(timer); } } EXPORT_SYMBOL(del_timer_sync); @@ -1207,15 +1257,17 @@ if (irqsafe) { spin_unlock(&base->lock); call_timer_fn(timer, fn, data); + base->running_timer = NULL; spin_lock(&base->lock); } else { spin_unlock_irq(&base->lock); call_timer_fn(timer, fn, data); + base->running_timer = NULL; spin_lock_irq(&base->lock); } } } - base->running_timer = NULL; + wakeup_timer_waiters(base); spin_unlock_irq(&base->lock); } @@ -1355,17 +1407,31 @@ if (cpu_is_offline(smp_processor_id())) return expires; +#ifdef CONFIG_PREEMPT_RT_FULL + /* + * On PREEMPT_RT we cannot sleep here. If the trylock does not + * succeed then we return the worst-case 'expires in 1 tick' + * value. We use the rt functions here directly to avoid a + * migrate_disable() call. + */ + if (!spin_do_trylock(&base->lock)) + return now + 1; +#else spin_lock(&base->lock); +#endif if (base->active_timers) { if (time_before_eq(base->next_timer, base->timer_jiffies)) base->next_timer = __next_timer_interrupt(base); expires = base->next_timer; } +#ifdef CONFIG_PREEMPT_RT_FULL + rt_spin_unlock_after_trylock_in_irq(&base->lock); +#else spin_unlock(&base->lock); +#endif if (time_before_eq(expires, now)) return now; - return cmp_next_hrtimer_event(now, expires); } #endif @@ -1381,13 +1447,13 @@ /* Note: this timer irq context must be accounted for as well. */ account_process_tick(p, user_tick); + scheduler_tick(); run_local_timers(); rcu_check_callbacks(cpu, user_tick); -#ifdef CONFIG_IRQ_WORK - if (in_irq()) - irq_work_tick(); + +#if defined(CONFIG_IRQ_WORK) && !defined(CONFIG_PREEMPT_RT_FULL) + irq_work_tick(); #endif - scheduler_tick(); run_posix_cpu_timers(p); } @@ -1400,6 +1466,10 @@ hrtimer_run_pending(); +#if defined(CONFIG_IRQ_WORK) && defined(CONFIG_PREEMPT_RT_FULL) + irq_work_tick(); +#endif + if (time_after_eq(jiffies, base->timer_jiffies)) __run_timers(base); } @@ -1574,6 +1644,9 @@ base = per_cpu(tvec_bases, cpu); } +#ifdef CONFIG_PREEMPT_RT_FULL + init_waitqueue_head(&base->wait_for_running_timer); +#endif for (j = 0; j < TVN_SIZE; j++) { INIT_LIST_HEAD(base->tv5.vec + j); @@ -1613,7 +1686,7 @@ BUG_ON(cpu_online(cpu)); old_base = per_cpu(tvec_bases, cpu); - new_base = get_cpu_var(tvec_bases); + new_base = get_local_var(tvec_bases); /* * The caller is globally serialized and nobody else * takes two locks at once, deadlock is not possible. @@ -1634,7 +1707,7 @@ spin_unlock(&old_base->lock); spin_unlock_irq(&new_base->lock); - put_cpu_var(tvec_bases); + put_local_var(tvec_bases); } #endif /* CONFIG_HOTPLUG_CPU */ diff -Nur linux-3.18.14.orig/kernel/trace/Kconfig linux-3.18.14-rt/kernel/trace/Kconfig --- linux-3.18.14.orig/kernel/trace/Kconfig 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/trace/Kconfig 2015-05-31 15:32:48.973635362 -0500 @@ -187,6 +187,24 @@ enabled. This option and the preempt-off timing option can be used together or separately.) +config INTERRUPT_OFF_HIST + bool "Interrupts-off Latency Histogram" + depends on IRQSOFF_TRACER + help + This option generates continuously updated histograms (one per cpu) + of the duration of time periods with interrupts disabled. The + histograms are disabled by default. To enable them, write a non-zero + number to + + /sys/kernel/debug/tracing/latency_hist/enable/preemptirqsoff + + If PREEMPT_OFF_HIST is also selected, additional histograms (one + per cpu) are generated that accumulate the duration of time periods + when both interrupts and preemption are disabled. The histogram data + will be located in the debug file system at + + /sys/kernel/debug/tracing/latency_hist/irqsoff + config PREEMPT_TRACER bool "Preemption-off Latency Tracer" default n @@ -211,6 +229,24 @@ enabled. This option and the irqs-off timing option can be used together or separately.) +config PREEMPT_OFF_HIST + bool "Preemption-off Latency Histogram" + depends on PREEMPT_TRACER + help + This option generates continuously updated histograms (one per cpu) + of the duration of time periods with preemption disabled. The + histograms are disabled by default. To enable them, write a non-zero + number to + + /sys/kernel/debug/tracing/latency_hist/enable/preemptirqsoff + + If INTERRUPT_OFF_HIST is also selected, additional histograms (one + per cpu) are generated that accumulate the duration of time periods + when both interrupts and preemption are disabled. The histogram data + will be located in the debug file system at + + /sys/kernel/debug/tracing/latency_hist/preemptoff + config SCHED_TRACER bool "Scheduling Latency Tracer" select GENERIC_TRACER @@ -221,6 +257,74 @@ This tracer tracks the latency of the highest priority task to be scheduled in, starting from the point it has woken up. +config WAKEUP_LATENCY_HIST + bool "Scheduling Latency Histogram" + depends on SCHED_TRACER + help + This option generates continuously updated histograms (one per cpu) + of the scheduling latency of the highest priority task. + The histograms are disabled by default. To enable them, write a + non-zero number to + + /sys/kernel/debug/tracing/latency_hist/enable/wakeup + + Two different algorithms are used, one to determine the latency of + processes that exclusively use the highest priority of the system and + another one to determine the latency of processes that share the + highest system priority with other processes. The former is used to + improve hardware and system software, the latter to optimize the + priority design of a given system. The histogram data will be + located in the debug file system at + + /sys/kernel/debug/tracing/latency_hist/wakeup + + and + + /sys/kernel/debug/tracing/latency_hist/wakeup/sharedprio + + If both Scheduling Latency Histogram and Missed Timer Offsets + Histogram are selected, additional histogram data will be collected + that contain, in addition to the wakeup latency, the timer latency, in + case the wakeup was triggered by an expired timer. These histograms + are available in the + + /sys/kernel/debug/tracing/latency_hist/timerandwakeup + + directory. They reflect the apparent interrupt and scheduling latency + and are best suitable to determine the worst-case latency of a given + system. To enable these histograms, write a non-zero number to + + /sys/kernel/debug/tracing/latency_hist/enable/timerandwakeup + +config MISSED_TIMER_OFFSETS_HIST + depends on HIGH_RES_TIMERS + select GENERIC_TRACER + bool "Missed Timer Offsets Histogram" + help + Generate a histogram of missed timer offsets in microseconds. The + histograms are disabled by default. To enable them, write a non-zero + number to + + /sys/kernel/debug/tracing/latency_hist/enable/missed_timer_offsets + + The histogram data will be located in the debug file system at + + /sys/kernel/debug/tracing/latency_hist/missed_timer_offsets + + If both Scheduling Latency Histogram and Missed Timer Offsets + Histogram are selected, additional histogram data will be collected + that contain, in addition to the wakeup latency, the timer latency, in + case the wakeup was triggered by an expired timer. These histograms + are available in the + + /sys/kernel/debug/tracing/latency_hist/timerandwakeup + + directory. They reflect the apparent interrupt and scheduling latency + and are best suitable to determine the worst-case latency of a given + system. To enable these histograms, write a non-zero number to + + /sys/kernel/debug/tracing/latency_hist/enable/timerandwakeup + config ENABLE_DEFAULT_TRACERS bool "Trace process context switches and events" depends on !GENERIC_TRACER diff -Nur linux-3.18.14.orig/kernel/trace/latency_hist.c linux-3.18.14-rt/kernel/trace/latency_hist.c --- linux-3.18.14.orig/kernel/trace/latency_hist.c 1969-12-31 18:00:00.000000000 -0600 +++ linux-3.18.14-rt/kernel/trace/latency_hist.c 2015-05-31 15:32:48.989635362 -0500 @@ -0,0 +1,1178 @@ +/* + * kernel/trace/latency_hist.c + * + * Add support for histograms of preemption-off latency and + * interrupt-off latency and wakeup latency, it depends on + * Real-Time Preemption Support. + * + * Copyright (C) 2005 MontaVista Software, Inc. + * Yi Yang + * + * Converted to work with the new latency tracer. + * Copyright (C) 2008 Red Hat, Inc. + * Steven Rostedt + * + */ +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "trace.h" +#include + +#define NSECS_PER_USECS 1000L + +#define CREATE_TRACE_POINTS +#include + +enum { + IRQSOFF_LATENCY = 0, + PREEMPTOFF_LATENCY, + PREEMPTIRQSOFF_LATENCY, + WAKEUP_LATENCY, + WAKEUP_LATENCY_SHAREDPRIO, + MISSED_TIMER_OFFSETS, + TIMERANDWAKEUP_LATENCY, + MAX_LATENCY_TYPE, +}; + +#define MAX_ENTRY_NUM 10240 + +struct hist_data { + atomic_t hist_mode; /* 0 log, 1 don't log */ + long offset; /* set it to MAX_ENTRY_NUM/2 for a bipolar scale */ + long min_lat; + long max_lat; + unsigned long long below_hist_bound_samples; + unsigned long long above_hist_bound_samples; + long long accumulate_lat; + unsigned long long total_samples; + unsigned long long hist_array[MAX_ENTRY_NUM]; +}; + +struct enable_data { + int latency_type; + int enabled; +}; + +static char *latency_hist_dir_root = "latency_hist"; + +#ifdef CONFIG_INTERRUPT_OFF_HIST +static DEFINE_PER_CPU(struct hist_data, irqsoff_hist); +static char *irqsoff_hist_dir = "irqsoff"; +static DEFINE_PER_CPU(cycles_t, hist_irqsoff_start); +static DEFINE_PER_CPU(int, hist_irqsoff_counting); +#endif + +#ifdef CONFIG_PREEMPT_OFF_HIST +static DEFINE_PER_CPU(struct hist_data, preemptoff_hist); +static char *preemptoff_hist_dir = "preemptoff"; +static DEFINE_PER_CPU(cycles_t, hist_preemptoff_start); +static DEFINE_PER_CPU(int, hist_preemptoff_counting); +#endif + +#if defined(CONFIG_PREEMPT_OFF_HIST) && defined(CONFIG_INTERRUPT_OFF_HIST) +static DEFINE_PER_CPU(struct hist_data, preemptirqsoff_hist); +static char *preemptirqsoff_hist_dir = "preemptirqsoff"; +static DEFINE_PER_CPU(cycles_t, hist_preemptirqsoff_start); +static DEFINE_PER_CPU(int, hist_preemptirqsoff_counting); +#endif + +#if defined(CONFIG_PREEMPT_OFF_HIST) || defined(CONFIG_INTERRUPT_OFF_HIST) +static notrace void probe_preemptirqsoff_hist(void *v, int reason, int start); +static struct enable_data preemptirqsoff_enabled_data = { + .latency_type = PREEMPTIRQSOFF_LATENCY, + .enabled = 0, +}; +#endif + +#if defined(CONFIG_WAKEUP_LATENCY_HIST) || \ + defined(CONFIG_MISSED_TIMER_OFFSETS_HIST) +struct maxlatproc_data { + char comm[FIELD_SIZEOF(struct task_struct, comm)]; + char current_comm[FIELD_SIZEOF(struct task_struct, comm)]; + int pid; + int current_pid; + int prio; + int current_prio; + long latency; + long timeroffset; + cycle_t timestamp; +}; +#endif + +#ifdef CONFIG_WAKEUP_LATENCY_HIST +static DEFINE_PER_CPU(struct hist_data, wakeup_latency_hist); +static DEFINE_PER_CPU(struct hist_data, wakeup_latency_hist_sharedprio); +static char *wakeup_latency_hist_dir = "wakeup"; +static char *wakeup_latency_hist_dir_sharedprio = "sharedprio"; +static notrace void probe_wakeup_latency_hist_start(void *v, + struct task_struct *p, int success); +static notrace void probe_wakeup_latency_hist_stop(void *v, + struct task_struct *prev, struct task_struct *next); +static notrace void probe_sched_migrate_task(void *, + struct task_struct *task, int cpu); +static struct enable_data wakeup_latency_enabled_data = { + .latency_type = WAKEUP_LATENCY, + .enabled = 0, +}; +static DEFINE_PER_CPU(struct maxlatproc_data, wakeup_maxlatproc); +static DEFINE_PER_CPU(struct maxlatproc_data, wakeup_maxlatproc_sharedprio); +static DEFINE_PER_CPU(struct task_struct *, wakeup_task); +static DEFINE_PER_CPU(int, wakeup_sharedprio); +static unsigned long wakeup_pid; +#endif + +#ifdef CONFIG_MISSED_TIMER_OFFSETS_HIST +static DEFINE_PER_CPU(struct hist_data, missed_timer_offsets); +static char *missed_timer_offsets_dir = "missed_timer_offsets"; +static notrace void probe_hrtimer_interrupt(void *v, int cpu, + long long offset, struct task_struct *curr, struct task_struct *task); +static struct enable_data missed_timer_offsets_enabled_data = { + .latency_type = MISSED_TIMER_OFFSETS, + .enabled = 0, +}; +static DEFINE_PER_CPU(struct maxlatproc_data, missed_timer_offsets_maxlatproc); +static unsigned long missed_timer_offsets_pid; +#endif + +#if defined(CONFIG_WAKEUP_LATENCY_HIST) && \ + defined(CONFIG_MISSED_TIMER_OFFSETS_HIST) +static DEFINE_PER_CPU(struct hist_data, timerandwakeup_latency_hist); +static char *timerandwakeup_latency_hist_dir = "timerandwakeup"; +static struct enable_data timerandwakeup_enabled_data = { + .latency_type = TIMERANDWAKEUP_LATENCY, + .enabled = 0, +}; +static DEFINE_PER_CPU(struct maxlatproc_data, timerandwakeup_maxlatproc); +#endif + +void notrace latency_hist(int latency_type, int cpu, long latency, + long timeroffset, cycle_t stop, + struct task_struct *p) +{ + struct hist_data *my_hist; +#if defined(CONFIG_WAKEUP_LATENCY_HIST) || \ + defined(CONFIG_MISSED_TIMER_OFFSETS_HIST) + struct maxlatproc_data *mp = NULL; +#endif + + if (!cpu_possible(cpu) || latency_type < 0 || + latency_type >= MAX_LATENCY_TYPE) + return; + + switch (latency_type) { +#ifdef CONFIG_INTERRUPT_OFF_HIST + case IRQSOFF_LATENCY: + my_hist = &per_cpu(irqsoff_hist, cpu); + break; +#endif +#ifdef CONFIG_PREEMPT_OFF_HIST + case PREEMPTOFF_LATENCY: + my_hist = &per_cpu(preemptoff_hist, cpu); + break; +#endif +#if defined(CONFIG_PREEMPT_OFF_HIST) && defined(CONFIG_INTERRUPT_OFF_HIST) + case PREEMPTIRQSOFF_LATENCY: + my_hist = &per_cpu(preemptirqsoff_hist, cpu); + break; +#endif +#ifdef CONFIG_WAKEUP_LATENCY_HIST + case WAKEUP_LATENCY: + my_hist = &per_cpu(wakeup_latency_hist, cpu); + mp = &per_cpu(wakeup_maxlatproc, cpu); + break; + case WAKEUP_LATENCY_SHAREDPRIO: + my_hist = &per_cpu(wakeup_latency_hist_sharedprio, cpu); + mp = &per_cpu(wakeup_maxlatproc_sharedprio, cpu); + break; +#endif +#ifdef CONFIG_MISSED_TIMER_OFFSETS_HIST + case MISSED_TIMER_OFFSETS: + my_hist = &per_cpu(missed_timer_offsets, cpu); + mp = &per_cpu(missed_timer_offsets_maxlatproc, cpu); + break; +#endif +#if defined(CONFIG_WAKEUP_LATENCY_HIST) && \ + defined(CONFIG_MISSED_TIMER_OFFSETS_HIST) + case TIMERANDWAKEUP_LATENCY: + my_hist = &per_cpu(timerandwakeup_latency_hist, cpu); + mp = &per_cpu(timerandwakeup_maxlatproc, cpu); + break; +#endif + + default: + return; + } + + latency += my_hist->offset; + + if (atomic_read(&my_hist->hist_mode) == 0) + return; + + if (latency < 0 || latency >= MAX_ENTRY_NUM) { + if (latency < 0) + my_hist->below_hist_bound_samples++; + else + my_hist->above_hist_bound_samples++; + } else + my_hist->hist_array[latency]++; + + if (unlikely(latency > my_hist->max_lat || + my_hist->min_lat == LONG_MAX)) { +#if defined(CONFIG_WAKEUP_LATENCY_HIST) || \ + defined(CONFIG_MISSED_TIMER_OFFSETS_HIST) + if (latency_type == WAKEUP_LATENCY || + latency_type == WAKEUP_LATENCY_SHAREDPRIO || + latency_type == MISSED_TIMER_OFFSETS || + latency_type == TIMERANDWAKEUP_LATENCY) { + strncpy(mp->comm, p->comm, sizeof(mp->comm)); + strncpy(mp->current_comm, current->comm, + sizeof(mp->current_comm)); + mp->pid = task_pid_nr(p); + mp->current_pid = task_pid_nr(current); + mp->prio = p->prio; + mp->current_prio = current->prio; + mp->latency = latency; + mp->timeroffset = timeroffset; + mp->timestamp = stop; + } +#endif + my_hist->max_lat = latency; + } + if (unlikely(latency < my_hist->min_lat)) + my_hist->min_lat = latency; + my_hist->total_samples++; + my_hist->accumulate_lat += latency; +} + +static void *l_start(struct seq_file *m, loff_t *pos) +{ + loff_t *index_ptr = NULL; + loff_t index = *pos; + struct hist_data *my_hist = m->private; + + if (index == 0) { + char minstr[32], avgstr[32], maxstr[32]; + + atomic_dec(&my_hist->hist_mode); + + if (likely(my_hist->total_samples)) { + long avg = (long) div64_s64(my_hist->accumulate_lat, + my_hist->total_samples); + snprintf(minstr, sizeof(minstr), "%ld", + my_hist->min_lat - my_hist->offset); + snprintf(avgstr, sizeof(avgstr), "%ld", + avg - my_hist->offset); + snprintf(maxstr, sizeof(maxstr), "%ld", + my_hist->max_lat - my_hist->offset); + } else { + strcpy(minstr, ""); + strcpy(avgstr, minstr); + strcpy(maxstr, minstr); + } + + seq_printf(m, "#Minimum latency: %s microseconds\n" + "#Average latency: %s microseconds\n" + "#Maximum latency: %s microseconds\n" + "#Total samples: %llu\n" + "#There are %llu samples lower than %ld" + " microseconds.\n" + "#There are %llu samples greater or equal" + " than %ld microseconds.\n" + "#usecs\t%16s\n", + minstr, avgstr, maxstr, + my_hist->total_samples, + my_hist->below_hist_bound_samples, + -my_hist->offset, + my_hist->above_hist_bound_samples, + MAX_ENTRY_NUM - my_hist->offset, + "samples"); + } + if (index < MAX_ENTRY_NUM) { + index_ptr = kmalloc(sizeof(loff_t), GFP_KERNEL); + if (index_ptr) + *index_ptr = index; + } + + return index_ptr; +} + +static void *l_next(struct seq_file *m, void *p, loff_t *pos) +{ + loff_t *index_ptr = p; + struct hist_data *my_hist = m->private; + + if (++*pos >= MAX_ENTRY_NUM) { + atomic_inc(&my_hist->hist_mode); + return NULL; + } + *index_ptr = *pos; + return index_ptr; +} + +static void l_stop(struct seq_file *m, void *p) +{ + kfree(p); +} + +static int l_show(struct seq_file *m, void *p) +{ + int index = *(loff_t *) p; + struct hist_data *my_hist = m->private; + + seq_printf(m, "%6ld\t%16llu\n", index - my_hist->offset, + my_hist->hist_array[index]); + return 0; +} + +static const struct seq_operations latency_hist_seq_op = { + .start = l_start, + .next = l_next, + .stop = l_stop, + .show = l_show +}; + +static int latency_hist_open(struct inode *inode, struct file *file) +{ + int ret; + + ret = seq_open(file, &latency_hist_seq_op); + if (!ret) { + struct seq_file *seq = file->private_data; + seq->private = inode->i_private; + } + return ret; +} + +static const struct file_operations latency_hist_fops = { + .open = latency_hist_open, + .read = seq_read, + .llseek = seq_lseek, + .release = seq_release, +}; + +#if defined(CONFIG_WAKEUP_LATENCY_HIST) || \ + defined(CONFIG_MISSED_TIMER_OFFSETS_HIST) +static void clear_maxlatprocdata(struct maxlatproc_data *mp) +{ + mp->comm[0] = mp->current_comm[0] = '\0'; + mp->prio = mp->current_prio = mp->pid = mp->current_pid = + mp->latency = mp->timeroffset = -1; + mp->timestamp = 0; +} +#endif + +static void hist_reset(struct hist_data *hist) +{ + atomic_dec(&hist->hist_mode); + + memset(hist->hist_array, 0, sizeof(hist->hist_array)); + hist->below_hist_bound_samples = 0ULL; + hist->above_hist_bound_samples = 0ULL; + hist->min_lat = LONG_MAX; + hist->max_lat = LONG_MIN; + hist->total_samples = 0ULL; + hist->accumulate_lat = 0LL; + + atomic_inc(&hist->hist_mode); +} + +static ssize_t +latency_hist_reset(struct file *file, const char __user *a, + size_t size, loff_t *off) +{ + int cpu; + struct hist_data *hist = NULL; +#if defined(CONFIG_WAKEUP_LATENCY_HIST) || \ + defined(CONFIG_MISSED_TIMER_OFFSETS_HIST) + struct maxlatproc_data *mp = NULL; +#endif + off_t latency_type = (off_t) file->private_data; + + for_each_online_cpu(cpu) { + + switch (latency_type) { +#ifdef CONFIG_PREEMPT_OFF_HIST + case PREEMPTOFF_LATENCY: + hist = &per_cpu(preemptoff_hist, cpu); + break; +#endif +#ifdef CONFIG_INTERRUPT_OFF_HIST + case IRQSOFF_LATENCY: + hist = &per_cpu(irqsoff_hist, cpu); + break; +#endif +#if defined(CONFIG_INTERRUPT_OFF_HIST) && defined(CONFIG_PREEMPT_OFF_HIST) + case PREEMPTIRQSOFF_LATENCY: + hist = &per_cpu(preemptirqsoff_hist, cpu); + break; +#endif +#ifdef CONFIG_WAKEUP_LATENCY_HIST + case WAKEUP_LATENCY: + hist = &per_cpu(wakeup_latency_hist, cpu); + mp = &per_cpu(wakeup_maxlatproc, cpu); + break; + case WAKEUP_LATENCY_SHAREDPRIO: + hist = &per_cpu(wakeup_latency_hist_sharedprio, cpu); + mp = &per_cpu(wakeup_maxlatproc_sharedprio, cpu); + break; +#endif +#ifdef CONFIG_MISSED_TIMER_OFFSETS_HIST + case MISSED_TIMER_OFFSETS: + hist = &per_cpu(missed_timer_offsets, cpu); + mp = &per_cpu(missed_timer_offsets_maxlatproc, cpu); + break; +#endif +#if defined(CONFIG_WAKEUP_LATENCY_HIST) && \ + defined(CONFIG_MISSED_TIMER_OFFSETS_HIST) + case TIMERANDWAKEUP_LATENCY: + hist = &per_cpu(timerandwakeup_latency_hist, cpu); + mp = &per_cpu(timerandwakeup_maxlatproc, cpu); + break; +#endif + } + + hist_reset(hist); +#if defined(CONFIG_WAKEUP_LATENCY_HIST) || \ + defined(CONFIG_MISSED_TIMER_OFFSETS_HIST) + if (latency_type == WAKEUP_LATENCY || + latency_type == WAKEUP_LATENCY_SHAREDPRIO || + latency_type == MISSED_TIMER_OFFSETS || + latency_type == TIMERANDWAKEUP_LATENCY) + clear_maxlatprocdata(mp); +#endif + } + + return size; +} + +#if defined(CONFIG_WAKEUP_LATENCY_HIST) || \ + defined(CONFIG_MISSED_TIMER_OFFSETS_HIST) +static ssize_t +show_pid(struct file *file, char __user *ubuf, size_t cnt, loff_t *ppos) +{ + char buf[64]; + int r; + unsigned long *this_pid = file->private_data; + + r = snprintf(buf, sizeof(buf), "%lu\n", *this_pid); + return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); +} + +static ssize_t do_pid(struct file *file, const char __user *ubuf, + size_t cnt, loff_t *ppos) +{ + char buf[64]; + unsigned long pid; + unsigned long *this_pid = file->private_data; + + if (cnt >= sizeof(buf)) + return -EINVAL; + + if (copy_from_user(&buf, ubuf, cnt)) + return -EFAULT; + + buf[cnt] = '\0'; + + if (kstrtoul(buf, 10, &pid)) + return -EINVAL; + + *this_pid = pid; + + return cnt; +} +#endif + +#if defined(CONFIG_WAKEUP_LATENCY_HIST) || \ + defined(CONFIG_MISSED_TIMER_OFFSETS_HIST) +static ssize_t +show_maxlatproc(struct file *file, char __user *ubuf, size_t cnt, loff_t *ppos) +{ + int r; + struct maxlatproc_data *mp = file->private_data; + int strmaxlen = (TASK_COMM_LEN * 2) + (8 * 8); + unsigned long long t; + unsigned long usecs, secs; + char *buf; + + if (mp->pid == -1 || mp->current_pid == -1) { + buf = "(none)\n"; + return simple_read_from_buffer(ubuf, cnt, ppos, buf, + strlen(buf)); + } + + buf = kmalloc(strmaxlen, GFP_KERNEL); + if (buf == NULL) + return -ENOMEM; + + t = ns2usecs(mp->timestamp); + usecs = do_div(t, USEC_PER_SEC); + secs = (unsigned long) t; + r = snprintf(buf, strmaxlen, + "%d %d %ld (%ld) %s <- %d %d %s %lu.%06lu\n", mp->pid, + MAX_RT_PRIO-1 - mp->prio, mp->latency, mp->timeroffset, mp->comm, + mp->current_pid, MAX_RT_PRIO-1 - mp->current_prio, mp->current_comm, + secs, usecs); + r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); + kfree(buf); + return r; +} +#endif + +static ssize_t +show_enable(struct file *file, char __user *ubuf, size_t cnt, loff_t *ppos) +{ + char buf[64]; + struct enable_data *ed = file->private_data; + int r; + + r = snprintf(buf, sizeof(buf), "%d\n", ed->enabled); + return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); +} + +static ssize_t +do_enable(struct file *file, const char __user *ubuf, size_t cnt, loff_t *ppos) +{ + char buf[64]; + long enable; + struct enable_data *ed = file->private_data; + + if (cnt >= sizeof(buf)) + return -EINVAL; + + if (copy_from_user(&buf, ubuf, cnt)) + return -EFAULT; + + buf[cnt] = 0; + + if (kstrtoul(buf, 10, &enable)) + return -EINVAL; + + if ((enable && ed->enabled) || (!enable && !ed->enabled)) + return cnt; + + if (enable) { + int ret; + + switch (ed->latency_type) { +#if defined(CONFIG_INTERRUPT_OFF_HIST) || defined(CONFIG_PREEMPT_OFF_HIST) + case PREEMPTIRQSOFF_LATENCY: + ret = register_trace_preemptirqsoff_hist( + probe_preemptirqsoff_hist, NULL); + if (ret) { + pr_info("wakeup trace: Couldn't assign " + "probe_preemptirqsoff_hist " + "to trace_preemptirqsoff_hist\n"); + return ret; + } + break; +#endif +#ifdef CONFIG_WAKEUP_LATENCY_HIST + case WAKEUP_LATENCY: + ret = register_trace_sched_wakeup( + probe_wakeup_latency_hist_start, NULL); + if (ret) { + pr_info("wakeup trace: Couldn't assign " + "probe_wakeup_latency_hist_start " + "to trace_sched_wakeup\n"); + return ret; + } + ret = register_trace_sched_wakeup_new( + probe_wakeup_latency_hist_start, NULL); + if (ret) { + pr_info("wakeup trace: Couldn't assign " + "probe_wakeup_latency_hist_start " + "to trace_sched_wakeup_new\n"); + unregister_trace_sched_wakeup( + probe_wakeup_latency_hist_start, NULL); + return ret; + } + ret = register_trace_sched_switch( + probe_wakeup_latency_hist_stop, NULL); + if (ret) { + pr_info("wakeup trace: Couldn't assign " + "probe_wakeup_latency_hist_stop " + "to trace_sched_switch\n"); + unregister_trace_sched_wakeup( + probe_wakeup_latency_hist_start, NULL); + unregister_trace_sched_wakeup_new( + probe_wakeup_latency_hist_start, NULL); + return ret; + } + ret = register_trace_sched_migrate_task( + probe_sched_migrate_task, NULL); + if (ret) { + pr_info("wakeup trace: Couldn't assign " + "probe_sched_migrate_task " + "to trace_sched_migrate_task\n"); + unregister_trace_sched_wakeup( + probe_wakeup_latency_hist_start, NULL); + unregister_trace_sched_wakeup_new( + probe_wakeup_latency_hist_start, NULL); + unregister_trace_sched_switch( + probe_wakeup_latency_hist_stop, NULL); + return ret; + } + break; +#endif +#ifdef CONFIG_MISSED_TIMER_OFFSETS_HIST + case MISSED_TIMER_OFFSETS: + ret = register_trace_hrtimer_interrupt( + probe_hrtimer_interrupt, NULL); + if (ret) { + pr_info("wakeup trace: Couldn't assign " + "probe_hrtimer_interrupt " + "to trace_hrtimer_interrupt\n"); + return ret; + } + break; +#endif +#if defined(CONFIG_WAKEUP_LATENCY_HIST) && \ + defined(CONFIG_MISSED_TIMER_OFFSETS_HIST) + case TIMERANDWAKEUP_LATENCY: + if (!wakeup_latency_enabled_data.enabled || + !missed_timer_offsets_enabled_data.enabled) + return -EINVAL; + break; +#endif + default: + break; + } + } else { + switch (ed->latency_type) { +#if defined(CONFIG_INTERRUPT_OFF_HIST) || defined(CONFIG_PREEMPT_OFF_HIST) + case PREEMPTIRQSOFF_LATENCY: + { + int cpu; + + unregister_trace_preemptirqsoff_hist( + probe_preemptirqsoff_hist, NULL); + for_each_online_cpu(cpu) { +#ifdef CONFIG_INTERRUPT_OFF_HIST + per_cpu(hist_irqsoff_counting, + cpu) = 0; +#endif +#ifdef CONFIG_PREEMPT_OFF_HIST + per_cpu(hist_preemptoff_counting, + cpu) = 0; +#endif +#if defined(CONFIG_INTERRUPT_OFF_HIST) && defined(CONFIG_PREEMPT_OFF_HIST) + per_cpu(hist_preemptirqsoff_counting, + cpu) = 0; +#endif + } + } + break; +#endif +#ifdef CONFIG_WAKEUP_LATENCY_HIST + case WAKEUP_LATENCY: + { + int cpu; + + unregister_trace_sched_wakeup( + probe_wakeup_latency_hist_start, NULL); + unregister_trace_sched_wakeup_new( + probe_wakeup_latency_hist_start, NULL); + unregister_trace_sched_switch( + probe_wakeup_latency_hist_stop, NULL); + unregister_trace_sched_migrate_task( + probe_sched_migrate_task, NULL); + + for_each_online_cpu(cpu) { + per_cpu(wakeup_task, cpu) = NULL; + per_cpu(wakeup_sharedprio, cpu) = 0; + } + } +#ifdef CONFIG_MISSED_TIMER_OFFSETS_HIST + timerandwakeup_enabled_data.enabled = 0; +#endif + break; +#endif +#ifdef CONFIG_MISSED_TIMER_OFFSETS_HIST + case MISSED_TIMER_OFFSETS: + unregister_trace_hrtimer_interrupt( + probe_hrtimer_interrupt, NULL); +#ifdef CONFIG_WAKEUP_LATENCY_HIST + timerandwakeup_enabled_data.enabled = 0; +#endif + break; +#endif + default: + break; + } + } + ed->enabled = enable; + return cnt; +} + +static const struct file_operations latency_hist_reset_fops = { + .open = tracing_open_generic, + .write = latency_hist_reset, +}; + +static const struct file_operations enable_fops = { + .open = tracing_open_generic, + .read = show_enable, + .write = do_enable, +}; + +#if defined(CONFIG_WAKEUP_LATENCY_HIST) || \ + defined(CONFIG_MISSED_TIMER_OFFSETS_HIST) +static const struct file_operations pid_fops = { + .open = tracing_open_generic, + .read = show_pid, + .write = do_pid, +}; + +static const struct file_operations maxlatproc_fops = { + .open = tracing_open_generic, + .read = show_maxlatproc, +}; +#endif + +#if defined(CONFIG_INTERRUPT_OFF_HIST) || defined(CONFIG_PREEMPT_OFF_HIST) +static notrace void probe_preemptirqsoff_hist(void *v, int reason, + int starthist) +{ + int cpu = raw_smp_processor_id(); + int time_set = 0; + + if (starthist) { + cycle_t uninitialized_var(start); + + if (!preempt_count() && !irqs_disabled()) + return; + +#ifdef CONFIG_INTERRUPT_OFF_HIST + if ((reason == IRQS_OFF || reason == TRACE_START) && + !per_cpu(hist_irqsoff_counting, cpu)) { + per_cpu(hist_irqsoff_counting, cpu) = 1; + start = ftrace_now(cpu); + time_set++; + per_cpu(hist_irqsoff_start, cpu) = start; + } +#endif + +#ifdef CONFIG_PREEMPT_OFF_HIST + if ((reason == PREEMPT_OFF || reason == TRACE_START) && + !per_cpu(hist_preemptoff_counting, cpu)) { + per_cpu(hist_preemptoff_counting, cpu) = 1; + if (!(time_set++)) + start = ftrace_now(cpu); + per_cpu(hist_preemptoff_start, cpu) = start; + } +#endif + +#if defined(CONFIG_INTERRUPT_OFF_HIST) && defined(CONFIG_PREEMPT_OFF_HIST) + if (per_cpu(hist_irqsoff_counting, cpu) && + per_cpu(hist_preemptoff_counting, cpu) && + !per_cpu(hist_preemptirqsoff_counting, cpu)) { + per_cpu(hist_preemptirqsoff_counting, cpu) = 1; + if (!time_set) + start = ftrace_now(cpu); + per_cpu(hist_preemptirqsoff_start, cpu) = start; + } +#endif + } else { + cycle_t uninitialized_var(stop); + +#ifdef CONFIG_INTERRUPT_OFF_HIST + if ((reason == IRQS_ON || reason == TRACE_STOP) && + per_cpu(hist_irqsoff_counting, cpu)) { + cycle_t start = per_cpu(hist_irqsoff_start, cpu); + + stop = ftrace_now(cpu); + time_set++; + if (start) { + long latency = ((long) (stop - start)) / + NSECS_PER_USECS; + + latency_hist(IRQSOFF_LATENCY, cpu, latency, 0, + stop, NULL); + } + per_cpu(hist_irqsoff_counting, cpu) = 0; + } +#endif + +#ifdef CONFIG_PREEMPT_OFF_HIST + if ((reason == PREEMPT_ON || reason == TRACE_STOP) && + per_cpu(hist_preemptoff_counting, cpu)) { + cycle_t start = per_cpu(hist_preemptoff_start, cpu); + + if (!(time_set++)) + stop = ftrace_now(cpu); + if (start) { + long latency = ((long) (stop - start)) / + NSECS_PER_USECS; + + latency_hist(PREEMPTOFF_LATENCY, cpu, latency, + 0, stop, NULL); + } + per_cpu(hist_preemptoff_counting, cpu) = 0; + } +#endif + +#if defined(CONFIG_INTERRUPT_OFF_HIST) && defined(CONFIG_PREEMPT_OFF_HIST) + if ((!per_cpu(hist_irqsoff_counting, cpu) || + !per_cpu(hist_preemptoff_counting, cpu)) && + per_cpu(hist_preemptirqsoff_counting, cpu)) { + cycle_t start = per_cpu(hist_preemptirqsoff_start, cpu); + + if (!time_set) + stop = ftrace_now(cpu); + if (start) { + long latency = ((long) (stop - start)) / + NSECS_PER_USECS; + + latency_hist(PREEMPTIRQSOFF_LATENCY, cpu, + latency, 0, stop, NULL); + } + per_cpu(hist_preemptirqsoff_counting, cpu) = 0; + } +#endif + } +} +#endif + +#ifdef CONFIG_WAKEUP_LATENCY_HIST +static DEFINE_RAW_SPINLOCK(wakeup_lock); +static notrace void probe_sched_migrate_task(void *v, struct task_struct *task, + int cpu) +{ + int old_cpu = task_cpu(task); + + if (cpu != old_cpu) { + unsigned long flags; + struct task_struct *cpu_wakeup_task; + + raw_spin_lock_irqsave(&wakeup_lock, flags); + + cpu_wakeup_task = per_cpu(wakeup_task, old_cpu); + if (task == cpu_wakeup_task) { + put_task_struct(cpu_wakeup_task); + per_cpu(wakeup_task, old_cpu) = NULL; + cpu_wakeup_task = per_cpu(wakeup_task, cpu) = task; + get_task_struct(cpu_wakeup_task); + } + + raw_spin_unlock_irqrestore(&wakeup_lock, flags); + } +} + +static notrace void probe_wakeup_latency_hist_start(void *v, + struct task_struct *p, int success) +{ + unsigned long flags; + struct task_struct *curr = current; + int cpu = task_cpu(p); + struct task_struct *cpu_wakeup_task; + + raw_spin_lock_irqsave(&wakeup_lock, flags); + + cpu_wakeup_task = per_cpu(wakeup_task, cpu); + + if (wakeup_pid) { + if ((cpu_wakeup_task && p->prio == cpu_wakeup_task->prio) || + p->prio == curr->prio) + per_cpu(wakeup_sharedprio, cpu) = 1; + if (likely(wakeup_pid != task_pid_nr(p))) + goto out; + } else { + if (likely(!rt_task(p)) || + (cpu_wakeup_task && p->prio > cpu_wakeup_task->prio) || + p->prio > curr->prio) + goto out; + if ((cpu_wakeup_task && p->prio == cpu_wakeup_task->prio) || + p->prio == curr->prio) + per_cpu(wakeup_sharedprio, cpu) = 1; + } + + if (cpu_wakeup_task) + put_task_struct(cpu_wakeup_task); + cpu_wakeup_task = per_cpu(wakeup_task, cpu) = p; + get_task_struct(cpu_wakeup_task); + cpu_wakeup_task->preempt_timestamp_hist = + ftrace_now(raw_smp_processor_id()); +out: + raw_spin_unlock_irqrestore(&wakeup_lock, flags); +} + +static notrace void probe_wakeup_latency_hist_stop(void *v, + struct task_struct *prev, struct task_struct *next) +{ + unsigned long flags; + int cpu = task_cpu(next); + long latency; + cycle_t stop; + struct task_struct *cpu_wakeup_task; + + raw_spin_lock_irqsave(&wakeup_lock, flags); + + cpu_wakeup_task = per_cpu(wakeup_task, cpu); + + if (cpu_wakeup_task == NULL) + goto out; + + /* Already running? */ + if (unlikely(current == cpu_wakeup_task)) + goto out_reset; + + if (next != cpu_wakeup_task) { + if (next->prio < cpu_wakeup_task->prio) + goto out_reset; + + if (next->prio == cpu_wakeup_task->prio) + per_cpu(wakeup_sharedprio, cpu) = 1; + + goto out; + } + + if (current->prio == cpu_wakeup_task->prio) + per_cpu(wakeup_sharedprio, cpu) = 1; + + /* + * The task we are waiting for is about to be switched to. + * Calculate latency and store it in histogram. + */ + stop = ftrace_now(raw_smp_processor_id()); + + latency = ((long) (stop - next->preempt_timestamp_hist)) / + NSECS_PER_USECS; + + if (per_cpu(wakeup_sharedprio, cpu)) { + latency_hist(WAKEUP_LATENCY_SHAREDPRIO, cpu, latency, 0, stop, + next); + per_cpu(wakeup_sharedprio, cpu) = 0; + } else { + latency_hist(WAKEUP_LATENCY, cpu, latency, 0, stop, next); +#ifdef CONFIG_MISSED_TIMER_OFFSETS_HIST + if (timerandwakeup_enabled_data.enabled) { + latency_hist(TIMERANDWAKEUP_LATENCY, cpu, + next->timer_offset + latency, next->timer_offset, + stop, next); + } +#endif + } + +out_reset: +#ifdef CONFIG_MISSED_TIMER_OFFSETS_HIST + next->timer_offset = 0; +#endif + put_task_struct(cpu_wakeup_task); + per_cpu(wakeup_task, cpu) = NULL; +out: + raw_spin_unlock_irqrestore(&wakeup_lock, flags); +} +#endif + +#ifdef CONFIG_MISSED_TIMER_OFFSETS_HIST +static notrace void probe_hrtimer_interrupt(void *v, int cpu, + long long latency_ns, struct task_struct *curr, + struct task_struct *task) +{ + if (latency_ns <= 0 && task != NULL && rt_task(task) && + (task->prio < curr->prio || + (task->prio == curr->prio && + !cpumask_test_cpu(cpu, &task->cpus_allowed)))) { + long latency; + cycle_t now; + + if (missed_timer_offsets_pid) { + if (likely(missed_timer_offsets_pid != + task_pid_nr(task))) + return; + } + + now = ftrace_now(cpu); + latency = (long) div_s64(-latency_ns, NSECS_PER_USECS); + latency_hist(MISSED_TIMER_OFFSETS, cpu, latency, latency, now, + task); +#ifdef CONFIG_WAKEUP_LATENCY_HIST + task->timer_offset = latency; +#endif + } +} +#endif + +static __init int latency_hist_init(void) +{ + struct dentry *latency_hist_root = NULL; + struct dentry *dentry; +#ifdef CONFIG_WAKEUP_LATENCY_HIST + struct dentry *dentry_sharedprio; +#endif + struct dentry *entry; + struct dentry *enable_root; + int i = 0; + struct hist_data *my_hist; + char name[64]; + char *cpufmt = "CPU%d"; +#if defined(CONFIG_WAKEUP_LATENCY_HIST) || \ + defined(CONFIG_MISSED_TIMER_OFFSETS_HIST) + char *cpufmt_maxlatproc = "max_latency-CPU%d"; + struct maxlatproc_data *mp = NULL; +#endif + + dentry = tracing_init_dentry(); + latency_hist_root = debugfs_create_dir(latency_hist_dir_root, dentry); + enable_root = debugfs_create_dir("enable", latency_hist_root); + +#ifdef CONFIG_INTERRUPT_OFF_HIST + dentry = debugfs_create_dir(irqsoff_hist_dir, latency_hist_root); + for_each_possible_cpu(i) { + sprintf(name, cpufmt, i); + entry = debugfs_create_file(name, 0444, dentry, + &per_cpu(irqsoff_hist, i), &latency_hist_fops); + my_hist = &per_cpu(irqsoff_hist, i); + atomic_set(&my_hist->hist_mode, 1); + my_hist->min_lat = LONG_MAX; + } + entry = debugfs_create_file("reset", 0644, dentry, + (void *)IRQSOFF_LATENCY, &latency_hist_reset_fops); +#endif + +#ifdef CONFIG_PREEMPT_OFF_HIST + dentry = debugfs_create_dir(preemptoff_hist_dir, + latency_hist_root); + for_each_possible_cpu(i) { + sprintf(name, cpufmt, i); + entry = debugfs_create_file(name, 0444, dentry, + &per_cpu(preemptoff_hist, i), &latency_hist_fops); + my_hist = &per_cpu(preemptoff_hist, i); + atomic_set(&my_hist->hist_mode, 1); + my_hist->min_lat = LONG_MAX; + } + entry = debugfs_create_file("reset", 0644, dentry, + (void *)PREEMPTOFF_LATENCY, &latency_hist_reset_fops); +#endif + +#if defined(CONFIG_INTERRUPT_OFF_HIST) && defined(CONFIG_PREEMPT_OFF_HIST) + dentry = debugfs_create_dir(preemptirqsoff_hist_dir, + latency_hist_root); + for_each_possible_cpu(i) { + sprintf(name, cpufmt, i); + entry = debugfs_create_file(name, 0444, dentry, + &per_cpu(preemptirqsoff_hist, i), &latency_hist_fops); + my_hist = &per_cpu(preemptirqsoff_hist, i); + atomic_set(&my_hist->hist_mode, 1); + my_hist->min_lat = LONG_MAX; + } + entry = debugfs_create_file("reset", 0644, dentry, + (void *)PREEMPTIRQSOFF_LATENCY, &latency_hist_reset_fops); +#endif + +#if defined(CONFIG_INTERRUPT_OFF_HIST) || defined(CONFIG_PREEMPT_OFF_HIST) + entry = debugfs_create_file("preemptirqsoff", 0644, + enable_root, (void *)&preemptirqsoff_enabled_data, + &enable_fops); +#endif + +#ifdef CONFIG_WAKEUP_LATENCY_HIST + dentry = debugfs_create_dir(wakeup_latency_hist_dir, + latency_hist_root); + dentry_sharedprio = debugfs_create_dir( + wakeup_latency_hist_dir_sharedprio, dentry); + for_each_possible_cpu(i) { + sprintf(name, cpufmt, i); + + entry = debugfs_create_file(name, 0444, dentry, + &per_cpu(wakeup_latency_hist, i), + &latency_hist_fops); + my_hist = &per_cpu(wakeup_latency_hist, i); + atomic_set(&my_hist->hist_mode, 1); + my_hist->min_lat = LONG_MAX; + + entry = debugfs_create_file(name, 0444, dentry_sharedprio, + &per_cpu(wakeup_latency_hist_sharedprio, i), + &latency_hist_fops); + my_hist = &per_cpu(wakeup_latency_hist_sharedprio, i); + atomic_set(&my_hist->hist_mode, 1); + my_hist->min_lat = LONG_MAX; + + sprintf(name, cpufmt_maxlatproc, i); + + mp = &per_cpu(wakeup_maxlatproc, i); + entry = debugfs_create_file(name, 0444, dentry, mp, + &maxlatproc_fops); + clear_maxlatprocdata(mp); + + mp = &per_cpu(wakeup_maxlatproc_sharedprio, i); + entry = debugfs_create_file(name, 0444, dentry_sharedprio, mp, + &maxlatproc_fops); + clear_maxlatprocdata(mp); + } + entry = debugfs_create_file("pid", 0644, dentry, + (void *)&wakeup_pid, &pid_fops); + entry = debugfs_create_file("reset", 0644, dentry, + (void *)WAKEUP_LATENCY, &latency_hist_reset_fops); + entry = debugfs_create_file("reset", 0644, dentry_sharedprio, + (void *)WAKEUP_LATENCY_SHAREDPRIO, &latency_hist_reset_fops); + entry = debugfs_create_file("wakeup", 0644, + enable_root, (void *)&wakeup_latency_enabled_data, + &enable_fops); +#endif + +#ifdef CONFIG_MISSED_TIMER_OFFSETS_HIST + dentry = debugfs_create_dir(missed_timer_offsets_dir, + latency_hist_root); + for_each_possible_cpu(i) { + sprintf(name, cpufmt, i); + entry = debugfs_create_file(name, 0444, dentry, + &per_cpu(missed_timer_offsets, i), &latency_hist_fops); + my_hist = &per_cpu(missed_timer_offsets, i); + atomic_set(&my_hist->hist_mode, 1); + my_hist->min_lat = LONG_MAX; + + sprintf(name, cpufmt_maxlatproc, i); + mp = &per_cpu(missed_timer_offsets_maxlatproc, i); + entry = debugfs_create_file(name, 0444, dentry, mp, + &maxlatproc_fops); + clear_maxlatprocdata(mp); + } + entry = debugfs_create_file("pid", 0644, dentry, + (void *)&missed_timer_offsets_pid, &pid_fops); + entry = debugfs_create_file("reset", 0644, dentry, + (void *)MISSED_TIMER_OFFSETS, &latency_hist_reset_fops); + entry = debugfs_create_file("missed_timer_offsets", 0644, + enable_root, (void *)&missed_timer_offsets_enabled_data, + &enable_fops); +#endif + +#if defined(CONFIG_WAKEUP_LATENCY_HIST) && \ + defined(CONFIG_MISSED_TIMER_OFFSETS_HIST) + dentry = debugfs_create_dir(timerandwakeup_latency_hist_dir, + latency_hist_root); + for_each_possible_cpu(i) { + sprintf(name, cpufmt, i); + entry = debugfs_create_file(name, 0444, dentry, + &per_cpu(timerandwakeup_latency_hist, i), + &latency_hist_fops); + my_hist = &per_cpu(timerandwakeup_latency_hist, i); + atomic_set(&my_hist->hist_mode, 1); + my_hist->min_lat = LONG_MAX; + + sprintf(name, cpufmt_maxlatproc, i); + mp = &per_cpu(timerandwakeup_maxlatproc, i); + entry = debugfs_create_file(name, 0444, dentry, mp, + &maxlatproc_fops); + clear_maxlatprocdata(mp); + } + entry = debugfs_create_file("reset", 0644, dentry, + (void *)TIMERANDWAKEUP_LATENCY, &latency_hist_reset_fops); + entry = debugfs_create_file("timerandwakeup", 0644, + enable_root, (void *)&timerandwakeup_enabled_data, + &enable_fops); +#endif + return 0; +} + +device_initcall(latency_hist_init); diff -Nur linux-3.18.14.orig/kernel/trace/Makefile linux-3.18.14-rt/kernel/trace/Makefile --- linux-3.18.14.orig/kernel/trace/Makefile 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/trace/Makefile 2015-05-31 15:32:48.989635362 -0500 @@ -36,6 +36,10 @@ obj-$(CONFIG_IRQSOFF_TRACER) += trace_irqsoff.o obj-$(CONFIG_PREEMPT_TRACER) += trace_irqsoff.o obj-$(CONFIG_SCHED_TRACER) += trace_sched_wakeup.o +obj-$(CONFIG_INTERRUPT_OFF_HIST) += latency_hist.o +obj-$(CONFIG_PREEMPT_OFF_HIST) += latency_hist.o +obj-$(CONFIG_WAKEUP_LATENCY_HIST) += latency_hist.o +obj-$(CONFIG_MISSED_TIMER_OFFSETS_HIST) += latency_hist.o obj-$(CONFIG_NOP_TRACER) += trace_nop.o obj-$(CONFIG_STACK_TRACER) += trace_stack.o obj-$(CONFIG_MMIOTRACE) += trace_mmiotrace.o diff -Nur linux-3.18.14.orig/kernel/trace/trace.c linux-3.18.14-rt/kernel/trace/trace.c --- linux-3.18.14.orig/kernel/trace/trace.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/trace/trace.c 2015-05-31 15:32:49.021635361 -0500 @@ -1579,6 +1579,7 @@ struct task_struct *tsk = current; entry->preempt_count = pc & 0xff; + entry->preempt_lazy_count = preempt_lazy_count(); entry->pid = (tsk) ? tsk->pid : 0; entry->flags = #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT @@ -1588,8 +1589,11 @@ #endif ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) | ((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) | - (tif_need_resched() ? TRACE_FLAG_NEED_RESCHED : 0) | + (tif_need_resched_now() ? TRACE_FLAG_NEED_RESCHED : 0) | + (need_resched_lazy() ? TRACE_FLAG_NEED_RESCHED_LAZY : 0) | (test_preempt_need_resched() ? TRACE_FLAG_PREEMPT_RESCHED : 0); + + entry->migrate_disable = (tsk) ? __migrate_disabled(tsk) & 0xFF : 0; } EXPORT_SYMBOL_GPL(tracing_generic_entry_update); @@ -2509,14 +2513,17 @@ static void print_lat_help_header(struct seq_file *m) { - seq_puts(m, "# _------=> CPU# \n"); - seq_puts(m, "# / _-----=> irqs-off \n"); - seq_puts(m, "# | / _----=> need-resched \n"); - seq_puts(m, "# || / _---=> hardirq/softirq \n"); - seq_puts(m, "# ||| / _--=> preempt-depth \n"); - seq_puts(m, "# |||| / delay \n"); - seq_puts(m, "# cmd pid ||||| time | caller \n"); - seq_puts(m, "# \\ / ||||| \\ | / \n"); + seq_puts(m, "# _--------=> CPU# \n"); + seq_puts(m, "# / _-------=> irqs-off \n"); + seq_puts(m, "# | / _------=> need-resched \n"); + seq_puts(m, "# || / _-----=> need-resched_lazy \n"); + seq_puts(m, "# ||| / _----=> hardirq/softirq \n"); + seq_puts(m, "# |||| / _---=> preempt-depth \n"); + seq_puts(m, "# ||||| / _--=> preempt-lazy-depth\n"); + seq_puts(m, "# |||||| / _-=> migrate-disable \n"); + seq_puts(m, "# ||||||| / delay \n"); + seq_puts(m, "# cmd pid |||||||| time | caller \n"); + seq_puts(m, "# \\ / |||||||| \\ | / \n"); } static void print_event_info(struct trace_buffer *buf, struct seq_file *m) @@ -2540,13 +2547,16 @@ static void print_func_help_header_irq(struct trace_buffer *buf, struct seq_file *m) { print_event_info(buf, m); - seq_puts(m, "# _-----=> irqs-off\n"); - seq_puts(m, "# / _----=> need-resched\n"); - seq_puts(m, "# | / _---=> hardirq/softirq\n"); - seq_puts(m, "# || / _--=> preempt-depth\n"); - seq_puts(m, "# ||| / delay\n"); - seq_puts(m, "# TASK-PID CPU# |||| TIMESTAMP FUNCTION\n"); - seq_puts(m, "# | | | |||| | |\n"); + seq_puts(m, "# _-------=> irqs-off \n"); + seq_puts(m, "# / _------=> need-resched \n"); + seq_puts(m, "# |/ _-----=> need-resched_lazy \n"); + seq_puts(m, "# ||/ _----=> hardirq/softirq \n"); + seq_puts(m, "# |||/ _---=> preempt-depth \n"); + seq_puts(m, "# ||||/ _--=> preempt-lazy-depth\n"); + seq_puts(m, "# ||||| / _-=> migrate-disable \n"); + seq_puts(m, "# |||||| / delay\n"); + seq_puts(m, "# TASK-PID CPU# |||||| TIMESTAMP FUNCTION\n"); + seq_puts(m, "# | | | |||||| | |\n"); } void diff -Nur linux-3.18.14.orig/kernel/trace/trace_events.c linux-3.18.14-rt/kernel/trace/trace_events.c --- linux-3.18.14.orig/kernel/trace/trace_events.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/trace/trace_events.c 2015-05-31 15:32:49.025635362 -0500 @@ -162,6 +162,8 @@ __common_field(unsigned char, flags); __common_field(unsigned char, preempt_count); __common_field(int, pid); + __common_field(unsigned short, migrate_disable); + __common_field(unsigned short, padding); return ret; } diff -Nur linux-3.18.14.orig/kernel/trace/trace.h linux-3.18.14-rt/kernel/trace/trace.h --- linux-3.18.14.orig/kernel/trace/trace.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/trace/trace.h 2015-05-31 15:32:49.021635361 -0500 @@ -119,6 +119,7 @@ * NEED_RESCHED - reschedule is requested * HARDIRQ - inside an interrupt handler * SOFTIRQ - inside a softirq handler + * NEED_RESCHED_LAZY - lazy reschedule is requested */ enum trace_flag_type { TRACE_FLAG_IRQS_OFF = 0x01, @@ -127,6 +128,7 @@ TRACE_FLAG_HARDIRQ = 0x08, TRACE_FLAG_SOFTIRQ = 0x10, TRACE_FLAG_PREEMPT_RESCHED = 0x20, + TRACE_FLAG_NEED_RESCHED_LAZY = 0x40, }; #define TRACE_BUF_SIZE 1024 diff -Nur linux-3.18.14.orig/kernel/trace/trace_irqsoff.c linux-3.18.14-rt/kernel/trace/trace_irqsoff.c --- linux-3.18.14.orig/kernel/trace/trace_irqsoff.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/trace/trace_irqsoff.c 2015-05-31 15:32:49.025635362 -0500 @@ -17,6 +17,7 @@ #include #include "trace.h" +#include static struct trace_array *irqsoff_trace __read_mostly; static int tracer_enabled __read_mostly; @@ -435,11 +436,13 @@ { if (preempt_trace() || irq_trace()) start_critical_timing(CALLER_ADDR0, CALLER_ADDR1); + trace_preemptirqsoff_hist(TRACE_START, 1); } EXPORT_SYMBOL_GPL(start_critical_timings); void stop_critical_timings(void) { + trace_preemptirqsoff_hist(TRACE_STOP, 0); if (preempt_trace() || irq_trace()) stop_critical_timing(CALLER_ADDR0, CALLER_ADDR1); } @@ -449,6 +452,7 @@ #ifdef CONFIG_PROVE_LOCKING void time_hardirqs_on(unsigned long a0, unsigned long a1) { + trace_preemptirqsoff_hist(IRQS_ON, 0); if (!preempt_trace() && irq_trace()) stop_critical_timing(a0, a1); } @@ -457,6 +461,7 @@ { if (!preempt_trace() && irq_trace()) start_critical_timing(a0, a1); + trace_preemptirqsoff_hist(IRQS_OFF, 1); } #else /* !CONFIG_PROVE_LOCKING */ @@ -482,6 +487,7 @@ */ void trace_hardirqs_on(void) { + trace_preemptirqsoff_hist(IRQS_ON, 0); if (!preempt_trace() && irq_trace()) stop_critical_timing(CALLER_ADDR0, CALLER_ADDR1); } @@ -491,11 +497,13 @@ { if (!preempt_trace() && irq_trace()) start_critical_timing(CALLER_ADDR0, CALLER_ADDR1); + trace_preemptirqsoff_hist(IRQS_OFF, 1); } EXPORT_SYMBOL(trace_hardirqs_off); __visible void trace_hardirqs_on_caller(unsigned long caller_addr) { + trace_preemptirqsoff_hist(IRQS_ON, 0); if (!preempt_trace() && irq_trace()) stop_critical_timing(CALLER_ADDR0, caller_addr); } @@ -505,6 +513,7 @@ { if (!preempt_trace() && irq_trace()) start_critical_timing(CALLER_ADDR0, caller_addr); + trace_preemptirqsoff_hist(IRQS_OFF, 1); } EXPORT_SYMBOL(trace_hardirqs_off_caller); @@ -514,12 +523,14 @@ #ifdef CONFIG_PREEMPT_TRACER void trace_preempt_on(unsigned long a0, unsigned long a1) { + trace_preemptirqsoff_hist(PREEMPT_ON, 0); if (preempt_trace() && !irq_trace()) stop_critical_timing(a0, a1); } void trace_preempt_off(unsigned long a0, unsigned long a1) { + trace_preemptirqsoff_hist(PREEMPT_ON, 1); if (preempt_trace() && !irq_trace()) start_critical_timing(a0, a1); } diff -Nur linux-3.18.14.orig/kernel/trace/trace_output.c linux-3.18.14-rt/kernel/trace/trace_output.c --- linux-3.18.14.orig/kernel/trace/trace_output.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/trace/trace_output.c 2015-05-31 15:32:49.025635362 -0500 @@ -410,6 +410,7 @@ { char hardsoft_irq; char need_resched; + char need_resched_lazy; char irqs_off; int hardirq; int softirq; @@ -438,6 +439,8 @@ need_resched = '.'; break; } + need_resched_lazy = + (entry->flags & TRACE_FLAG_NEED_RESCHED_LAZY) ? 'L' : '.'; hardsoft_irq = (hardirq && softirq) ? 'H' : @@ -445,8 +448,9 @@ softirq ? 's' : '.'; - if (!trace_seq_printf(s, "%c%c%c", - irqs_off, need_resched, hardsoft_irq)) + if (!trace_seq_printf(s, "%c%c%c%c", + irqs_off, need_resched, need_resched_lazy, + hardsoft_irq)) return 0; if (entry->preempt_count) @@ -454,6 +458,16 @@ else ret = trace_seq_putc(s, '.'); + if (entry->preempt_lazy_count) + ret = trace_seq_printf(s, "%x", entry->preempt_lazy_count); + else + ret = trace_seq_putc(s, '.'); + + if (entry->migrate_disable) + ret = trace_seq_printf(s, "%x", entry->migrate_disable); + else + ret = trace_seq_putc(s, '.'); + return ret; } diff -Nur linux-3.18.14.orig/kernel/user.c linux-3.18.14-rt/kernel/user.c --- linux-3.18.14.orig/kernel/user.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/user.c 2015-05-31 15:32:49.045635362 -0500 @@ -158,11 +158,11 @@ if (!up) return; - local_irq_save(flags); + local_irq_save_nort(flags); if (atomic_dec_and_lock(&up->__count, &uidhash_lock)) free_user(up, flags); else - local_irq_restore(flags); + local_irq_restore_nort(flags); } struct user_struct *alloc_uid(kuid_t uid) diff -Nur linux-3.18.14.orig/kernel/watchdog.c linux-3.18.14-rt/kernel/watchdog.c --- linux-3.18.14.orig/kernel/watchdog.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/watchdog.c 2015-05-31 15:32:49.065635361 -0500 @@ -248,6 +248,8 @@ #ifdef CONFIG_HARDLOCKUP_DETECTOR +static DEFINE_RAW_SPINLOCK(watchdog_output_lock); + static struct perf_event_attr wd_hw_attr = { .type = PERF_TYPE_HARDWARE, .config = PERF_COUNT_HW_CPU_CYCLES, @@ -281,13 +283,21 @@ /* only print hardlockups once */ if (__this_cpu_read(hard_watchdog_warn) == true) return; + /* + * If early-printk is enabled then make sure we do not + * lock up in printk() and kill console logging: + */ + printk_kill(); - if (hardlockup_panic) + if (hardlockup_panic) { panic("Watchdog detected hard LOCKUP on cpu %d", this_cpu); - else + } else { + raw_spin_lock(&watchdog_output_lock); WARN(1, "Watchdog detected hard LOCKUP on cpu %d", this_cpu); + raw_spin_unlock(&watchdog_output_lock); + } __this_cpu_write(hard_watchdog_warn, true); return; @@ -430,6 +440,7 @@ /* kick off the timer for the hardlockup detector */ hrtimer_init(hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); hrtimer->function = watchdog_timer_fn; + hrtimer->irqsafe = 1; /* Enable the perf event */ watchdog_nmi_enable(cpu); diff -Nur linux-3.18.14.orig/kernel/workqueue.c linux-3.18.14-rt/kernel/workqueue.c --- linux-3.18.14.orig/kernel/workqueue.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/workqueue.c 2015-05-31 15:32:49.069635361 -0500 @@ -48,6 +48,8 @@ #include #include #include +#include +#include #include "workqueue_internal.h" @@ -121,15 +123,20 @@ * cpu or grabbing pool->lock is enough for read access. If * POOL_DISASSOCIATED is set, it's identical to L. * + * On RT we need the extra protection via rt_lock_idle_list() for + * the list manipulations against read access from + * wq_worker_sleeping(). All other places are nicely serialized via + * pool->lock. + * * A: pool->attach_mutex protected. * * PL: wq_pool_mutex protected. * - * PR: wq_pool_mutex protected for writes. Sched-RCU protected for reads. + * PR: wq_pool_mutex protected for writes. RCU protected for reads. * * WQ: wq->mutex protected. * - * WR: wq->mutex protected for writes. Sched-RCU protected for reads. + * WR: wq->mutex protected for writes. RCU protected for reads. * * MD: wq_mayday_lock protected. */ @@ -177,7 +184,7 @@ atomic_t nr_running ____cacheline_aligned_in_smp; /* - * Destruction of pool is sched-RCU protected to allow dereferences + * Destruction of pool is RCU protected to allow dereferences * from get_work_pool(). */ struct rcu_head rcu; @@ -206,7 +213,7 @@ /* * Release of unbound pwq is punted to system_wq. See put_pwq() * and pwq_unbound_release_workfn() for details. pool_workqueue - * itself is also sched-RCU protected so that the first pwq can be + * itself is also RCU protected so that the first pwq can be * determined without grabbing wq->mutex. */ struct work_struct unbound_release_work; @@ -321,6 +328,8 @@ struct workqueue_struct *system_freezable_power_efficient_wq __read_mostly; EXPORT_SYMBOL_GPL(system_freezable_power_efficient_wq); +static DEFINE_LOCAL_IRQ_LOCK(pendingb_lock); + static int worker_thread(void *__worker); static void copy_workqueue_attrs(struct workqueue_attrs *to, const struct workqueue_attrs *from); @@ -329,14 +338,14 @@ #include #define assert_rcu_or_pool_mutex() \ - rcu_lockdep_assert(rcu_read_lock_sched_held() || \ + rcu_lockdep_assert(rcu_read_lock_held() || \ lockdep_is_held(&wq_pool_mutex), \ - "sched RCU or wq_pool_mutex should be held") + "RCU or wq_pool_mutex should be held") #define assert_rcu_or_wq_mutex(wq) \ - rcu_lockdep_assert(rcu_read_lock_sched_held() || \ + rcu_lockdep_assert(rcu_read_lock_held() || \ lockdep_is_held(&wq->mutex), \ - "sched RCU or wq->mutex should be held") + "RCU or wq->mutex should be held") #define for_each_cpu_worker_pool(pool, cpu) \ for ((pool) = &per_cpu(cpu_worker_pools, cpu)[0]; \ @@ -348,7 +357,7 @@ * @pool: iteration cursor * @pi: integer used for iteration * - * This must be called either with wq_pool_mutex held or sched RCU read + * This must be called either with wq_pool_mutex held or RCU read * locked. If the pool needs to be used beyond the locking in effect, the * caller is responsible for guaranteeing that the pool stays online. * @@ -380,7 +389,7 @@ * @pwq: iteration cursor * @wq: the target workqueue * - * This must be called either with wq->mutex held or sched RCU read locked. + * This must be called either with wq->mutex held or RCU read locked. * If the pwq needs to be used beyond the locking in effect, the caller is * responsible for guaranteeing that the pwq stays online. * @@ -392,6 +401,31 @@ if (({ assert_rcu_or_wq_mutex(wq); false; })) { } \ else +#ifdef CONFIG_PREEMPT_RT_BASE +static inline void rt_lock_idle_list(struct worker_pool *pool) +{ + preempt_disable(); +} +static inline void rt_unlock_idle_list(struct worker_pool *pool) +{ + preempt_enable(); +} +static inline void sched_lock_idle_list(struct worker_pool *pool) { } +static inline void sched_unlock_idle_list(struct worker_pool *pool) { } +#else +static inline void rt_lock_idle_list(struct worker_pool *pool) { } +static inline void rt_unlock_idle_list(struct worker_pool *pool) { } +static inline void sched_lock_idle_list(struct worker_pool *pool) +{ + spin_lock_irq(&pool->lock); +} +static inline void sched_unlock_idle_list(struct worker_pool *pool) +{ + spin_unlock_irq(&pool->lock); +} +#endif + + #ifdef CONFIG_DEBUG_OBJECTS_WORK static struct debug_obj_descr work_debug_descr; @@ -542,7 +576,7 @@ * @wq: the target workqueue * @node: the node ID * - * This must be called either with pwq_lock held or sched RCU read locked. + * This must be called either with pwq_lock held or RCU read locked. * If the pwq needs to be used beyond the locking in effect, the caller is * responsible for guaranteeing that the pwq stays online. * @@ -646,8 +680,8 @@ * @work: the work item of interest * * Pools are created and destroyed under wq_pool_mutex, and allows read - * access under sched-RCU read lock. As such, this function should be - * called under wq_pool_mutex or with preemption disabled. + * access under RCU read lock. As such, this function should be + * called under wq_pool_mutex or inside of a rcu_read_lock() region. * * All fields of the returned pool are accessible as long as the above * mentioned locking is in effect. If the returned pool needs to be used @@ -784,51 +818,44 @@ */ static void wake_up_worker(struct worker_pool *pool) { - struct worker *worker = first_idle_worker(pool); + struct worker *worker; + + rt_lock_idle_list(pool); + + worker = first_idle_worker(pool); if (likely(worker)) wake_up_process(worker->task); + + rt_unlock_idle_list(pool); } /** - * wq_worker_waking_up - a worker is waking up - * @task: task waking up - * @cpu: CPU @task is waking up to - * - * This function is called during try_to_wake_up() when a worker is - * being awoken. + * wq_worker_running - a worker is running again + * @task: task returning from sleep * - * CONTEXT: - * spin_lock_irq(rq->lock) + * This function is called when a worker returns from schedule() */ -void wq_worker_waking_up(struct task_struct *task, int cpu) +void wq_worker_running(struct task_struct *task) { struct worker *worker = kthread_data(task); - if (!(worker->flags & WORKER_NOT_RUNNING)) { - WARN_ON_ONCE(worker->pool->cpu != cpu); + if (!worker->sleeping) + return; + if (!(worker->flags & WORKER_NOT_RUNNING)) atomic_inc(&worker->pool->nr_running); - } + worker->sleeping = 0; } /** * wq_worker_sleeping - a worker is going to sleep * @task: task going to sleep - * @cpu: CPU in question, must be the current CPU number - * - * This function is called during schedule() when a busy worker is - * going to sleep. Worker on the same cpu can be woken up by - * returning pointer to its task. - * - * CONTEXT: - * spin_lock_irq(rq->lock) - * - * Return: - * Worker task on @cpu to wake up, %NULL if none. + * This function is called from schedule() when a busy worker is + * going to sleep. */ -struct task_struct *wq_worker_sleeping(struct task_struct *task, int cpu) +void wq_worker_sleeping(struct task_struct *task) { - struct worker *worker = kthread_data(task), *to_wakeup = NULL; + struct worker *worker = kthread_data(task); struct worker_pool *pool; /* @@ -837,29 +864,26 @@ * checking NOT_RUNNING. */ if (worker->flags & WORKER_NOT_RUNNING) - return NULL; + return; pool = worker->pool; - /* this can only happen on the local cpu */ - if (WARN_ON_ONCE(cpu != raw_smp_processor_id() || pool->cpu != cpu)) - return NULL; + if (WARN_ON_ONCE(worker->sleeping)) + return; + + worker->sleeping = 1; /* * The counterpart of the following dec_and_test, implied mb, * worklist not empty test sequence is in insert_work(). * Please read comment there. - * - * NOT_RUNNING is clear. This means that we're bound to and - * running on the local cpu w/ rq lock held and preemption - * disabled, which in turn means that none else could be - * manipulating idle_list, so dereferencing idle_list without pool - * lock is safe. */ if (atomic_dec_and_test(&pool->nr_running) && - !list_empty(&pool->worklist)) - to_wakeup = first_idle_worker(pool); - return to_wakeup ? to_wakeup->task : NULL; + !list_empty(&pool->worklist)) { + sched_lock_idle_list(pool); + wake_up_worker(pool); + sched_unlock_idle_list(pool); + } } /** @@ -1053,12 +1077,12 @@ { if (pwq) { /* - * As both pwqs and pools are sched-RCU protected, the + * As both pwqs and pools are RCU protected, the * following lock operations are safe. */ - spin_lock_irq(&pwq->pool->lock); + local_spin_lock_irq(pendingb_lock, &pwq->pool->lock); put_pwq(pwq); - spin_unlock_irq(&pwq->pool->lock); + local_spin_unlock_irq(pendingb_lock, &pwq->pool->lock); } } @@ -1160,7 +1184,7 @@ struct worker_pool *pool; struct pool_workqueue *pwq; - local_irq_save(*flags); + local_lock_irqsave(pendingb_lock, *flags); /* try to steal the timer if it exists */ if (is_dwork) { @@ -1179,6 +1203,7 @@ if (!test_and_set_bit(WORK_STRUCT_PENDING_BIT, work_data_bits(work))) return 0; + rcu_read_lock(); /* * The queueing is in progress, or it is already queued. Try to * steal it from ->worklist without clearing WORK_STRUCT_PENDING. @@ -1217,14 +1242,16 @@ set_work_pool_and_keep_pending(work, pool->id); spin_unlock(&pool->lock); + rcu_read_unlock(); return 1; } spin_unlock(&pool->lock); fail: - local_irq_restore(*flags); + rcu_read_unlock(); + local_unlock_irqrestore(pendingb_lock, *flags); if (work_is_canceling(work)) return -ENOENT; - cpu_relax(); + cpu_chill(); return -EAGAIN; } @@ -1293,7 +1320,7 @@ * queued or lose PENDING. Grabbing PENDING and queueing should * happen with IRQ disabled. */ - WARN_ON_ONCE(!irqs_disabled()); + WARN_ON_ONCE_NONRT(!irqs_disabled()); debug_work_activate(work); @@ -1301,6 +1328,8 @@ if (unlikely(wq->flags & __WQ_DRAINING) && WARN_ON_ONCE(!is_chained_work(wq))) return; + + rcu_read_lock(); retry: if (req_cpu == WORK_CPU_UNBOUND) cpu = raw_smp_processor_id(); @@ -1357,10 +1386,8 @@ /* pwq determined, queue */ trace_workqueue_queue_work(req_cpu, pwq, work); - if (WARN_ON(!list_empty(&work->entry))) { - spin_unlock(&pwq->pool->lock); - return; - } + if (WARN_ON(!list_empty(&work->entry))) + goto out; pwq->nr_in_flight[pwq->work_color]++; work_flags = work_color_to_flags(pwq->work_color); @@ -1376,7 +1403,9 @@ insert_work(pwq, work, worklist, work_flags); +out: spin_unlock(&pwq->pool->lock); + rcu_read_unlock(); } /** @@ -1396,14 +1425,14 @@ bool ret = false; unsigned long flags; - local_irq_save(flags); + local_lock_irqsave(pendingb_lock,flags); if (!test_and_set_bit(WORK_STRUCT_PENDING_BIT, work_data_bits(work))) { __queue_work(cpu, wq, work); ret = true; } - local_irq_restore(flags); + local_unlock_irqrestore(pendingb_lock, flags); return ret; } EXPORT_SYMBOL(queue_work_on); @@ -1470,14 +1499,14 @@ unsigned long flags; /* read the comment in __queue_work() */ - local_irq_save(flags); + local_lock_irqsave(pendingb_lock, flags); if (!test_and_set_bit(WORK_STRUCT_PENDING_BIT, work_data_bits(work))) { __queue_delayed_work(cpu, wq, dwork, delay); ret = true; } - local_irq_restore(flags); + local_unlock_irqrestore(pendingb_lock, flags); return ret; } EXPORT_SYMBOL(queue_delayed_work_on); @@ -1512,7 +1541,7 @@ if (likely(ret >= 0)) { __queue_delayed_work(cpu, wq, dwork, delay); - local_irq_restore(flags); + local_unlock_irqrestore(pendingb_lock, flags); } /* -ENOENT from try_to_grab_pending() becomes %true */ @@ -1545,7 +1574,9 @@ worker->last_active = jiffies; /* idle_list is LIFO */ + rt_lock_idle_list(pool); list_add(&worker->entry, &pool->idle_list); + rt_unlock_idle_list(pool); if (too_many_workers(pool) && !timer_pending(&pool->idle_timer)) mod_timer(&pool->idle_timer, jiffies + IDLE_WORKER_TIMEOUT); @@ -1578,7 +1609,9 @@ return; worker_clr_flags(worker, WORKER_IDLE); pool->nr_idle--; + rt_lock_idle_list(pool); list_del_init(&worker->entry); + rt_unlock_idle_list(pool); } static struct worker *alloc_worker(int node) @@ -1746,7 +1779,9 @@ pool->nr_workers--; pool->nr_idle--; + rt_lock_idle_list(pool); list_del_init(&worker->entry); + rt_unlock_idle_list(pool); worker->flags |= WORKER_DIE; wake_up_process(worker->task); } @@ -2641,14 +2676,14 @@ might_sleep(); - local_irq_disable(); + rcu_read_lock(); pool = get_work_pool(work); if (!pool) { - local_irq_enable(); + rcu_read_unlock(); return false; } - spin_lock(&pool->lock); + spin_lock_irq(&pool->lock); /* see the comment in try_to_grab_pending() with the same code */ pwq = get_work_pwq(work); if (pwq) { @@ -2675,10 +2710,11 @@ else lock_map_acquire_read(&pwq->wq->lockdep_map); lock_map_release(&pwq->wq->lockdep_map); - + rcu_read_unlock(); return true; already_gone: spin_unlock_irq(&pool->lock); + rcu_read_unlock(); return false; } @@ -2765,7 +2801,7 @@ /* tell other tasks trying to grab @work to back off */ mark_work_canceling(work); - local_irq_restore(flags); + local_unlock_irqrestore(pendingb_lock, flags); flush_work(work); clear_work_data(work); @@ -2820,10 +2856,10 @@ */ bool flush_delayed_work(struct delayed_work *dwork) { - local_irq_disable(); + local_lock_irq(pendingb_lock); if (del_timer_sync(&dwork->timer)) __queue_work(dwork->cpu, dwork->wq, &dwork->work); - local_irq_enable(); + local_unlock_irq(pendingb_lock); return flush_work(&dwork->work); } EXPORT_SYMBOL(flush_delayed_work); @@ -2858,7 +2894,7 @@ set_work_pool_and_clear_pending(&dwork->work, get_work_pool_id(&dwork->work)); - local_irq_restore(flags); + local_unlock_irqrestore(pendingb_lock, flags); return ret; } EXPORT_SYMBOL(cancel_delayed_work); @@ -3044,7 +3080,8 @@ const char *delim = ""; int node, written = 0; - rcu_read_lock_sched(); + get_online_cpus(); + rcu_read_lock(); for_each_node(node) { written += scnprintf(buf + written, PAGE_SIZE - written, "%s%d:%d", delim, node, @@ -3052,7 +3089,8 @@ delim = " "; } written += scnprintf(buf + written, PAGE_SIZE - written, "\n"); - rcu_read_unlock_sched(); + rcu_read_unlock(); + put_online_cpus(); return written; } @@ -3420,7 +3458,7 @@ * put_unbound_pool - put a worker_pool * @pool: worker_pool to put * - * Put @pool. If its refcnt reaches zero, it gets destroyed in sched-RCU + * Put @pool. If its refcnt reaches zero, it gets destroyed in RCU * safe manner. get_unbound_pool() calls this function on its failure path * and this function should be able to release pools which went through, * successfully or not, init_worker_pool(). @@ -3474,8 +3512,8 @@ del_timer_sync(&pool->idle_timer); del_timer_sync(&pool->mayday_timer); - /* sched-RCU protected to allow dereferences from get_work_pool() */ - call_rcu_sched(&pool->rcu, rcu_free_pool); + /* RCU protected to allow dereferences from get_work_pool() */ + call_rcu(&pool->rcu, rcu_free_pool); } /** @@ -3580,7 +3618,7 @@ put_unbound_pool(pool); mutex_unlock(&wq_pool_mutex); - call_rcu_sched(&pwq->rcu, rcu_free_pwq); + call_rcu(&pwq->rcu, rcu_free_pwq); /* * If we're the last pwq going away, @wq is already dead and no one @@ -4292,7 +4330,8 @@ struct pool_workqueue *pwq; bool ret; - rcu_read_lock_sched(); + rcu_read_lock(); + preempt_disable(); if (cpu == WORK_CPU_UNBOUND) cpu = smp_processor_id(); @@ -4303,7 +4342,8 @@ pwq = unbound_pwq_by_node(wq, cpu_to_node(cpu)); ret = !list_empty(&pwq->delayed_works); - rcu_read_unlock_sched(); + preempt_enable(); + rcu_read_unlock(); return ret; } @@ -4329,16 +4369,15 @@ if (work_pending(work)) ret |= WORK_BUSY_PENDING; - local_irq_save(flags); + rcu_read_lock(); pool = get_work_pool(work); if (pool) { - spin_lock(&pool->lock); + spin_lock_irqsave(&pool->lock, flags); if (find_worker_executing_work(pool, work)) ret |= WORK_BUSY_RUNNING; - spin_unlock(&pool->lock); + spin_unlock_irqrestore(&pool->lock, flags); } - local_irq_restore(flags); - + rcu_read_unlock(); return ret; } EXPORT_SYMBOL_GPL(work_busy); @@ -4767,16 +4806,16 @@ * nr_active is monotonically decreasing. It's safe * to peek without lock. */ - rcu_read_lock_sched(); + rcu_read_lock(); for_each_pwq(pwq, wq) { WARN_ON_ONCE(pwq->nr_active < 0); if (pwq->nr_active) { busy = true; - rcu_read_unlock_sched(); + rcu_read_unlock(); goto out_unlock; } } - rcu_read_unlock_sched(); + rcu_read_unlock(); } out_unlock: mutex_unlock(&wq_pool_mutex); diff -Nur linux-3.18.14.orig/kernel/workqueue_internal.h linux-3.18.14-rt/kernel/workqueue_internal.h --- linux-3.18.14.orig/kernel/workqueue_internal.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/kernel/workqueue_internal.h 2015-05-31 15:32:49.069635361 -0500 @@ -43,6 +43,7 @@ unsigned long last_active; /* L: last active timestamp */ unsigned int flags; /* X: flags */ int id; /* I: worker id */ + int sleeping; /* None */ /* * Opaque string set with work_set_desc(). Printed out with task @@ -68,7 +69,7 @@ * Scheduler hooks for concurrency managed workqueue. Only to be used from * sched/core.c and workqueue.c. */ -void wq_worker_waking_up(struct task_struct *task, int cpu); -struct task_struct *wq_worker_sleeping(struct task_struct *task, int cpu); +void wq_worker_running(struct task_struct *task); +void wq_worker_sleeping(struct task_struct *task); #endif /* _KERNEL_WORKQUEUE_INTERNAL_H */ diff -Nur linux-3.18.14.orig/lib/debugobjects.c linux-3.18.14-rt/lib/debugobjects.c --- linux-3.18.14.orig/lib/debugobjects.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/lib/debugobjects.c 2015-05-31 15:32:49.113635361 -0500 @@ -309,7 +309,10 @@ struct debug_obj *obj; unsigned long flags; - fill_pool(); +#ifdef CONFIG_PREEMPT_RT_FULL + if (preempt_count() == 0 && !irqs_disabled()) +#endif + fill_pool(); db = get_bucket((unsigned long) addr); diff -Nur linux-3.18.14.orig/lib/idr.c linux-3.18.14-rt/lib/idr.c --- linux-3.18.14.orig/lib/idr.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/lib/idr.c 2015-05-31 15:32:49.141635361 -0500 @@ -31,6 +31,7 @@ #include #include #include +#include #define MAX_IDR_SHIFT (sizeof(int) * 8 - 1) #define MAX_IDR_BIT (1U << MAX_IDR_SHIFT) @@ -367,6 +368,35 @@ idr_mark_full(pa, id); } +#ifdef CONFIG_PREEMPT_RT_FULL +static DEFINE_LOCAL_IRQ_LOCK(idr_lock); + +static inline void idr_preload_lock(void) +{ + local_lock(idr_lock); +} + +static inline void idr_preload_unlock(void) +{ + local_unlock(idr_lock); +} + +void idr_preload_end(void) +{ + idr_preload_unlock(); +} +EXPORT_SYMBOL(idr_preload_end); +#else +static inline void idr_preload_lock(void) +{ + preempt_disable(); +} + +static inline void idr_preload_unlock(void) +{ + preempt_enable(); +} +#endif /** * idr_preload - preload for idr_alloc() @@ -402,7 +432,7 @@ WARN_ON_ONCE(in_interrupt()); might_sleep_if(gfp_mask & __GFP_WAIT); - preempt_disable(); + idr_preload_lock(); /* * idr_alloc() is likely to succeed w/o full idr_layer buffer and @@ -414,9 +444,9 @@ while (__this_cpu_read(idr_preload_cnt) < MAX_IDR_FREE) { struct idr_layer *new; - preempt_enable(); + idr_preload_unlock(); new = kmem_cache_zalloc(idr_layer_cache, gfp_mask); - preempt_disable(); + idr_preload_lock(); if (!new) break; diff -Nur linux-3.18.14.orig/lib/Kconfig linux-3.18.14-rt/lib/Kconfig --- linux-3.18.14.orig/lib/Kconfig 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/lib/Kconfig 2015-05-31 15:32:49.085635361 -0500 @@ -383,6 +383,7 @@ config CPUMASK_OFFSTACK bool "Force CPU masks off stack" if DEBUG_PER_CPU_MAPS + depends on !PREEMPT_RT_FULL help Use dynamic allocation for cpumask_var_t, instead of putting them on the stack. This is a bit more expensive, but avoids diff -Nur linux-3.18.14.orig/lib/Kconfig.debug linux-3.18.14-rt/lib/Kconfig.debug --- linux-3.18.14.orig/lib/Kconfig.debug 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/lib/Kconfig.debug 2015-05-31 15:32:49.097635361 -0500 @@ -639,7 +639,7 @@ config DEBUG_SHIRQ bool "Debug shared IRQ handlers" - depends on DEBUG_KERNEL + depends on DEBUG_KERNEL && !PREEMPT_RT_BASE help Enable this to generate a spurious interrupt as soon as a shared interrupt handler is registered, and just before one is deregistered. diff -Nur linux-3.18.14.orig/lib/locking-selftest.c linux-3.18.14-rt/lib/locking-selftest.c --- linux-3.18.14.orig/lib/locking-selftest.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/lib/locking-selftest.c 2015-05-31 15:32:49.141635361 -0500 @@ -590,6 +590,8 @@ #include "locking-selftest-spin-hardirq.h" GENERATE_PERMUTATIONS_2_EVENTS(irqsafe1_hard_spin) +#ifndef CONFIG_PREEMPT_RT_FULL + #include "locking-selftest-rlock-hardirq.h" GENERATE_PERMUTATIONS_2_EVENTS(irqsafe1_hard_rlock) @@ -605,9 +607,12 @@ #include "locking-selftest-wlock-softirq.h" GENERATE_PERMUTATIONS_2_EVENTS(irqsafe1_soft_wlock) +#endif + #undef E1 #undef E2 +#ifndef CONFIG_PREEMPT_RT_FULL /* * Enabling hardirqs with a softirq-safe lock held: */ @@ -640,6 +645,8 @@ #undef E1 #undef E2 +#endif + /* * Enabling irqs with an irq-safe lock held: */ @@ -663,6 +670,8 @@ #include "locking-selftest-spin-hardirq.h" GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_hard_spin) +#ifndef CONFIG_PREEMPT_RT_FULL + #include "locking-selftest-rlock-hardirq.h" GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_hard_rlock) @@ -678,6 +687,8 @@ #include "locking-selftest-wlock-softirq.h" GENERATE_PERMUTATIONS_2_EVENTS(irqsafe2B_soft_wlock) +#endif + #undef E1 #undef E2 @@ -709,6 +720,8 @@ #include "locking-selftest-spin-hardirq.h" GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_hard_spin) +#ifndef CONFIG_PREEMPT_RT_FULL + #include "locking-selftest-rlock-hardirq.h" GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_hard_rlock) @@ -724,6 +737,8 @@ #include "locking-selftest-wlock-softirq.h" GENERATE_PERMUTATIONS_3_EVENTS(irqsafe3_soft_wlock) +#endif + #undef E1 #undef E2 #undef E3 @@ -757,6 +772,8 @@ #include "locking-selftest-spin-hardirq.h" GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_hard_spin) +#ifndef CONFIG_PREEMPT_RT_FULL + #include "locking-selftest-rlock-hardirq.h" GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_hard_rlock) @@ -772,10 +789,14 @@ #include "locking-selftest-wlock-softirq.h" GENERATE_PERMUTATIONS_3_EVENTS(irqsafe4_soft_wlock) +#endif + #undef E1 #undef E2 #undef E3 +#ifndef CONFIG_PREEMPT_RT_FULL + /* * read-lock / write-lock irq inversion. * @@ -838,6 +859,10 @@ #undef E2 #undef E3 +#endif + +#ifndef CONFIG_PREEMPT_RT_FULL + /* * read-lock / write-lock recursion that is actually safe. */ @@ -876,6 +901,8 @@ #undef E2 #undef E3 +#endif + /* * read-lock / write-lock recursion that is unsafe. */ @@ -1858,6 +1885,7 @@ printk(" --------------------------------------------------------------------------\n"); +#ifndef CONFIG_PREEMPT_RT_FULL /* * irq-context testcases: */ @@ -1870,6 +1898,28 @@ DO_TESTCASE_6x2("irq read-recursion", irq_read_recursion); // DO_TESTCASE_6x2B("irq read-recursion #2", irq_read_recursion2); +#else + /* On -rt, we only do hardirq context test for raw spinlock */ + DO_TESTCASE_1B("hard-irqs-on + irq-safe-A", irqsafe1_hard_spin, 12); + DO_TESTCASE_1B("hard-irqs-on + irq-safe-A", irqsafe1_hard_spin, 21); + + DO_TESTCASE_1B("hard-safe-A + irqs-on", irqsafe2B_hard_spin, 12); + DO_TESTCASE_1B("hard-safe-A + irqs-on", irqsafe2B_hard_spin, 21); + + DO_TESTCASE_1B("hard-safe-A + unsafe-B #1", irqsafe3_hard_spin, 123); + DO_TESTCASE_1B("hard-safe-A + unsafe-B #1", irqsafe3_hard_spin, 132); + DO_TESTCASE_1B("hard-safe-A + unsafe-B #1", irqsafe3_hard_spin, 213); + DO_TESTCASE_1B("hard-safe-A + unsafe-B #1", irqsafe3_hard_spin, 231); + DO_TESTCASE_1B("hard-safe-A + unsafe-B #1", irqsafe3_hard_spin, 312); + DO_TESTCASE_1B("hard-safe-A + unsafe-B #1", irqsafe3_hard_spin, 321); + + DO_TESTCASE_1B("hard-safe-A + unsafe-B #2", irqsafe4_hard_spin, 123); + DO_TESTCASE_1B("hard-safe-A + unsafe-B #2", irqsafe4_hard_spin, 132); + DO_TESTCASE_1B("hard-safe-A + unsafe-B #2", irqsafe4_hard_spin, 213); + DO_TESTCASE_1B("hard-safe-A + unsafe-B #2", irqsafe4_hard_spin, 231); + DO_TESTCASE_1B("hard-safe-A + unsafe-B #2", irqsafe4_hard_spin, 312); + DO_TESTCASE_1B("hard-safe-A + unsafe-B #2", irqsafe4_hard_spin, 321); +#endif ww_tests(); diff -Nur linux-3.18.14.orig/lib/percpu_ida.c linux-3.18.14-rt/lib/percpu_ida.c --- linux-3.18.14.orig/lib/percpu_ida.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/lib/percpu_ida.c 2015-05-31 15:32:49.161635360 -0500 @@ -29,6 +29,9 @@ #include #include #include +#include + +static DEFINE_LOCAL_IRQ_LOCK(irq_off_lock); struct percpu_ida_cpu { /* @@ -151,13 +154,13 @@ unsigned long flags; int tag; - local_irq_save(flags); + local_lock_irqsave(irq_off_lock, flags); tags = this_cpu_ptr(pool->tag_cpu); /* Fastpath */ tag = alloc_local_tag(tags); if (likely(tag >= 0)) { - local_irq_restore(flags); + local_unlock_irqrestore(irq_off_lock, flags); return tag; } @@ -176,6 +179,7 @@ if (!tags->nr_free) alloc_global_tags(pool, tags); + if (!tags->nr_free) steal_tags(pool, tags); @@ -187,7 +191,7 @@ } spin_unlock(&pool->lock); - local_irq_restore(flags); + local_unlock_irqrestore(irq_off_lock, flags); if (tag >= 0 || state == TASK_RUNNING) break; @@ -199,7 +203,7 @@ schedule(); - local_irq_save(flags); + local_lock_irqsave(irq_off_lock, flags); tags = this_cpu_ptr(pool->tag_cpu); } if (state != TASK_RUNNING) @@ -224,7 +228,7 @@ BUG_ON(tag >= pool->nr_tags); - local_irq_save(flags); + local_lock_irqsave(irq_off_lock, flags); tags = this_cpu_ptr(pool->tag_cpu); spin_lock(&tags->lock); @@ -256,7 +260,7 @@ spin_unlock(&pool->lock); } - local_irq_restore(flags); + local_unlock_irqrestore(irq_off_lock, flags); } EXPORT_SYMBOL_GPL(percpu_ida_free); @@ -348,7 +352,7 @@ struct percpu_ida_cpu *remote; unsigned cpu, i, err = 0; - local_irq_save(flags); + local_lock_irqsave(irq_off_lock, flags); for_each_possible_cpu(cpu) { remote = per_cpu_ptr(pool->tag_cpu, cpu); spin_lock(&remote->lock); @@ -370,7 +374,7 @@ } spin_unlock(&pool->lock); out: - local_irq_restore(flags); + local_unlock_irqrestore(irq_off_lock, flags); return err; } EXPORT_SYMBOL_GPL(percpu_ida_for_each_free); diff -Nur linux-3.18.14.orig/lib/radix-tree.c linux-3.18.14-rt/lib/radix-tree.c --- linux-3.18.14.orig/lib/radix-tree.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/lib/radix-tree.c 2015-05-31 15:32:49.161635360 -0500 @@ -195,12 +195,13 @@ * succeed in getting a node here (and never reach * kmem_cache_alloc) */ - rtp = this_cpu_ptr(&radix_tree_preloads); + rtp = &get_cpu_var(radix_tree_preloads); if (rtp->nr) { ret = rtp->nodes[rtp->nr - 1]; rtp->nodes[rtp->nr - 1] = NULL; rtp->nr--; } + put_cpu_var(radix_tree_preloads); /* * Update the allocation stack trace as this is more useful * for debugging. @@ -240,6 +241,7 @@ call_rcu(&node->rcu_head, radix_tree_node_rcu_free); } +#ifndef CONFIG_PREEMPT_RT_FULL /* * Load up this CPU's radix_tree_node buffer with sufficient objects to * ensure that the addition of a single element in the tree cannot fail. On @@ -305,6 +307,7 @@ return 0; } EXPORT_SYMBOL(radix_tree_maybe_preload); +#endif /* * Return the maximum key which can be store into a diff -Nur linux-3.18.14.orig/lib/scatterlist.c linux-3.18.14-rt/lib/scatterlist.c --- linux-3.18.14.orig/lib/scatterlist.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/lib/scatterlist.c 2015-05-31 15:32:49.161635360 -0500 @@ -592,7 +592,7 @@ flush_kernel_dcache_page(miter->page); if (miter->__flags & SG_MITER_ATOMIC) { - WARN_ON_ONCE(preemptible()); + WARN_ON_ONCE(!pagefault_disabled()); kunmap_atomic(miter->addr); } else kunmap(miter->page); @@ -637,7 +637,7 @@ if (!sg_miter_skip(&miter, skip)) return false; - local_irq_save(flags); + local_irq_save_nort(flags); while (sg_miter_next(&miter) && offset < buflen) { unsigned int len; @@ -654,7 +654,7 @@ sg_miter_stop(&miter); - local_irq_restore(flags); + local_irq_restore_nort(flags); return offset; } diff -Nur linux-3.18.14.orig/lib/smp_processor_id.c linux-3.18.14-rt/lib/smp_processor_id.c --- linux-3.18.14.orig/lib/smp_processor_id.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/lib/smp_processor_id.c 2015-05-31 15:32:49.161635360 -0500 @@ -39,8 +39,9 @@ if (!printk_ratelimit()) goto out_enable; - printk(KERN_ERR "BUG: using %s%s() in preemptible [%08x] code: %s/%d\n", - what1, what2, preempt_count() - 1, current->comm, current->pid); + printk(KERN_ERR "BUG: using %s%s() in preemptible [%08x %08x] code: %s/%d\n", + what1, what2, preempt_count() - 1, __migrate_disabled(current), + current->comm, current->pid); print_symbol("caller is %s\n", (long)__builtin_return_address(0)); dump_stack(); diff -Nur linux-3.18.14.orig/mm/filemap.c linux-3.18.14-rt/mm/filemap.c --- linux-3.18.14.orig/mm/filemap.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/mm/filemap.c 2015-05-31 15:32:49.181635360 -0500 @@ -168,7 +168,9 @@ if (!workingset_node_pages(node) && list_empty(&node->private_list)) { node->private_data = mapping; - list_lru_add(&workingset_shadow_nodes, &node->private_list); + local_lock(workingset_shadow_lock); + list_lru_add(&__workingset_shadow_nodes, &node->private_list); + local_unlock(workingset_shadow_lock); } } @@ -535,9 +537,12 @@ * node->private_list is protected by * mapping->tree_lock. */ - if (!list_empty(&node->private_list)) - list_lru_del(&workingset_shadow_nodes, + if (!list_empty(&node->private_list)) { + local_lock(workingset_shadow_lock); + list_lru_del(&__workingset_shadow_nodes, &node->private_list); + local_unlock(workingset_shadow_lock); + } } return 0; } diff -Nur linux-3.18.14.orig/mm/highmem.c linux-3.18.14-rt/mm/highmem.c --- linux-3.18.14.orig/mm/highmem.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/mm/highmem.c 2015-05-31 15:32:49.201635360 -0500 @@ -29,10 +29,11 @@ #include #include - +#ifndef CONFIG_PREEMPT_RT_FULL #if defined(CONFIG_HIGHMEM) || defined(CONFIG_X86_32) DEFINE_PER_CPU(int, __kmap_atomic_idx); #endif +#endif /* * Virtual_count is not a pure "count". @@ -107,8 +108,9 @@ unsigned long totalhigh_pages __read_mostly; EXPORT_SYMBOL(totalhigh_pages); - +#ifndef CONFIG_PREEMPT_RT_FULL EXPORT_PER_CPU_SYMBOL(__kmap_atomic_idx); +#endif unsigned int nr_free_highpages (void) { diff -Nur linux-3.18.14.orig/mm/Kconfig linux-3.18.14-rt/mm/Kconfig --- linux-3.18.14.orig/mm/Kconfig 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/mm/Kconfig 2015-05-31 15:32:49.177635360 -0500 @@ -408,7 +408,7 @@ config TRANSPARENT_HUGEPAGE bool "Transparent Hugepage Support" - depends on HAVE_ARCH_TRANSPARENT_HUGEPAGE + depends on HAVE_ARCH_TRANSPARENT_HUGEPAGE && !PREEMPT_RT_FULL select COMPACTION help Transparent Hugepages allows the kernel to use huge pages and diff -Nur linux-3.18.14.orig/mm/memcontrol.c linux-3.18.14-rt/mm/memcontrol.c --- linux-3.18.14.orig/mm/memcontrol.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/mm/memcontrol.c 2015-05-31 15:32:49.213635360 -0500 @@ -60,6 +60,8 @@ #include #include #include +#include + #include "slab.h" #include @@ -87,6 +89,7 @@ #define do_swap_account 0 #endif +static DEFINE_LOCAL_IRQ_LOCK(event_lock); static const char * const mem_cgroup_stat_names[] = { "cache", @@ -2376,14 +2379,17 @@ */ static void refill_stock(struct mem_cgroup *memcg, unsigned int nr_pages) { - struct memcg_stock_pcp *stock = &get_cpu_var(memcg_stock); + struct memcg_stock_pcp *stock; + int cpu = get_cpu_light(); + + stock = &per_cpu(memcg_stock, cpu); if (stock->cached != memcg) { /* reset if necessary */ drain_stock(stock); stock->cached = memcg; } stock->nr_pages += nr_pages; - put_cpu_var(memcg_stock); + put_cpu_light(); } /* @@ -2397,7 +2403,7 @@ /* Notify other cpus that system-wide "drain" is running */ get_online_cpus(); - curcpu = get_cpu(); + curcpu = get_cpu_light(); for_each_online_cpu(cpu) { struct memcg_stock_pcp *stock = &per_cpu(memcg_stock, cpu); struct mem_cgroup *memcg; @@ -2414,7 +2420,7 @@ schedule_work_on(cpu, &stock->work); } } - put_cpu(); + put_cpu_light(); if (!sync) goto out; @@ -3419,12 +3425,12 @@ move_unlock_mem_cgroup(from, &flags); ret = 0; - local_irq_disable(); + local_lock_irq(event_lock); mem_cgroup_charge_statistics(to, page, nr_pages); memcg_check_events(to, page); mem_cgroup_charge_statistics(from, page, -nr_pages); memcg_check_events(from, page); - local_irq_enable(); + local_unlock_irq(event_lock); out_unlock: unlock_page(page); out: @@ -6406,10 +6412,10 @@ VM_BUG_ON_PAGE(!PageTransHuge(page), page); } - local_irq_disable(); + local_lock_irq(event_lock); mem_cgroup_charge_statistics(memcg, page, nr_pages); memcg_check_events(memcg, page); - local_irq_enable(); + local_unlock_irq(event_lock); if (do_swap_account && PageSwapCache(page)) { swp_entry_t entry = { .val = page_private(page) }; @@ -6468,14 +6474,14 @@ memcg_oom_recover(memcg); } - local_irq_save(flags); + local_lock_irqsave(event_lock, flags); __this_cpu_sub(memcg->stat->count[MEM_CGROUP_STAT_RSS], nr_anon); __this_cpu_sub(memcg->stat->count[MEM_CGROUP_STAT_CACHE], nr_file); __this_cpu_sub(memcg->stat->count[MEM_CGROUP_STAT_RSS_HUGE], nr_huge); __this_cpu_add(memcg->stat->events[MEM_CGROUP_EVENTS_PGPGOUT], pgpgout); __this_cpu_add(memcg->stat->nr_page_events, nr_anon + nr_file); memcg_check_events(memcg, dummy_page); - local_irq_restore(flags); + local_unlock_irqrestore(event_lock, flags); } static void uncharge_list(struct list_head *page_list) diff -Nur linux-3.18.14.orig/mm/memory.c linux-3.18.14-rt/mm/memory.c --- linux-3.18.14.orig/mm/memory.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/mm/memory.c 2015-05-31 15:32:49.229635360 -0500 @@ -3244,6 +3244,32 @@ return 0; } +#ifdef CONFIG_PREEMPT_RT_FULL +void pagefault_disable(void) +{ + migrate_disable(); + current->pagefault_disabled++; + /* + * make sure to have issued the store before a pagefault + * can hit. + */ + barrier(); +} +EXPORT_SYMBOL(pagefault_disable); + +void pagefault_enable(void) +{ + /* + * make sure to issue those last loads/stores before enabling + * the pagefault handler again. + */ + barrier(); + current->pagefault_disabled--; + migrate_enable(); +} +EXPORT_SYMBOL(pagefault_enable); +#endif + /* * By the time we get here, we already hold the mm semaphore * diff -Nur linux-3.18.14.orig/mm/mmu_context.c linux-3.18.14-rt/mm/mmu_context.c --- linux-3.18.14.orig/mm/mmu_context.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/mm/mmu_context.c 2015-05-31 15:32:49.249635360 -0500 @@ -23,6 +23,7 @@ struct task_struct *tsk = current; task_lock(tsk); + preempt_disable_rt(); active_mm = tsk->active_mm; if (active_mm != mm) { atomic_inc(&mm->mm_count); @@ -30,6 +31,7 @@ } tsk->mm = mm; switch_mm(active_mm, mm, tsk); + preempt_enable_rt(); task_unlock(tsk); #ifdef finish_arch_post_lock_switch finish_arch_post_lock_switch(); diff -Nur linux-3.18.14.orig/mm/page_alloc.c linux-3.18.14-rt/mm/page_alloc.c --- linux-3.18.14.orig/mm/page_alloc.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/mm/page_alloc.c 2015-05-31 15:32:49.253635359 -0500 @@ -59,6 +59,7 @@ #include #include #include +#include #include #include @@ -230,6 +231,18 @@ EXPORT_SYMBOL(nr_online_nodes); #endif +static DEFINE_LOCAL_IRQ_LOCK(pa_lock); + +#ifdef CONFIG_PREEMPT_RT_BASE +# define cpu_lock_irqsave(cpu, flags) \ + local_lock_irqsave_on(pa_lock, flags, cpu) +# define cpu_unlock_irqrestore(cpu, flags) \ + local_unlock_irqrestore_on(pa_lock, flags, cpu) +#else +# define cpu_lock_irqsave(cpu, flags) local_irq_save(flags) +# define cpu_unlock_irqrestore(cpu, flags) local_irq_restore(flags) +#endif + int page_group_by_mobility_disabled __read_mostly; void set_pageblock_migratetype(struct page *page, int migratetype) @@ -654,7 +667,7 @@ } /* - * Frees a number of pages from the PCP lists + * Frees a number of pages which have been collected from the pcp lists. * Assumes all pages on list are in same zone, and of same order. * count is the number of pages to free. * @@ -665,18 +678,51 @@ * pinned" detection logic. */ static void free_pcppages_bulk(struct zone *zone, int count, - struct per_cpu_pages *pcp) + struct list_head *list) { - int migratetype = 0; - int batch_free = 0; int to_free = count; unsigned long nr_scanned; + unsigned long flags; + + spin_lock_irqsave(&zone->lock, flags); - spin_lock(&zone->lock); nr_scanned = zone_page_state(zone, NR_PAGES_SCANNED); if (nr_scanned) __mod_zone_page_state(zone, NR_PAGES_SCANNED, -nr_scanned); + while (!list_empty(list)) { + struct page *page = list_first_entry(list, struct page, lru); + int mt; /* migratetype of the to-be-freed page */ + + /* must delete as __free_one_page list manipulates */ + list_del(&page->lru); + + mt = get_freepage_migratetype(page); + if (unlikely(has_isolate_pageblock(zone))) + mt = get_pageblock_migratetype(page); + + /* MIGRATE_MOVABLE list may include MIGRATE_RESERVEs */ + __free_one_page(page, page_to_pfn(page), zone, 0, mt); + trace_mm_page_pcpu_drain(page, 0, mt); + to_free--; + } + WARN_ON(to_free != 0); + spin_unlock_irqrestore(&zone->lock, flags); +} + +/* + * Moves a number of pages from the PCP lists to free list which + * is freed outside of the locked region. + * + * Assumes all pages on list are in same zone, and of same order. + * count is the number of pages to free. + */ +static void isolate_pcp_pages(int to_free, struct per_cpu_pages *src, + struct list_head *dst) +{ + int migratetype = 0; + int batch_free = 0; + while (to_free) { struct page *page; struct list_head *list; @@ -692,7 +738,7 @@ batch_free++; if (++migratetype == MIGRATE_PCPTYPES) migratetype = 0; - list = &pcp->lists[migratetype]; + list = &src->lists[migratetype]; } while (list_empty(list)); /* This is the only non-empty list. Free them all. */ @@ -700,21 +746,11 @@ batch_free = to_free; do { - int mt; /* migratetype of the to-be-freed page */ - - page = list_entry(list->prev, struct page, lru); - /* must delete as __free_one_page list manipulates */ + page = list_last_entry(list, struct page, lru); list_del(&page->lru); - mt = get_freepage_migratetype(page); - if (unlikely(has_isolate_pageblock(zone))) - mt = get_pageblock_migratetype(page); - - /* MIGRATE_MOVABLE list may include MIGRATE_RESERVEs */ - __free_one_page(page, page_to_pfn(page), zone, 0, mt); - trace_mm_page_pcpu_drain(page, 0, mt); + list_add(&page->lru, dst); } while (--to_free && --batch_free && !list_empty(list)); } - spin_unlock(&zone->lock); } static void free_one_page(struct zone *zone, @@ -723,7 +759,9 @@ int migratetype) { unsigned long nr_scanned; - spin_lock(&zone->lock); + unsigned long flags; + + spin_lock_irqsave(&zone->lock, flags); nr_scanned = zone_page_state(zone, NR_PAGES_SCANNED); if (nr_scanned) __mod_zone_page_state(zone, NR_PAGES_SCANNED, -nr_scanned); @@ -733,7 +771,7 @@ migratetype = get_pfnblock_migratetype(page, pfn); } __free_one_page(page, pfn, zone, order, migratetype); - spin_unlock(&zone->lock); + spin_unlock_irqrestore(&zone->lock, flags); } static bool free_pages_prepare(struct page *page, unsigned int order) @@ -773,11 +811,11 @@ return; migratetype = get_pfnblock_migratetype(page, pfn); - local_irq_save(flags); + local_lock_irqsave(pa_lock, flags); __count_vm_events(PGFREE, 1 << order); set_freepage_migratetype(page, migratetype); free_one_page(page_zone(page), page, pfn, order, migratetype); - local_irq_restore(flags); + local_unlock_irqrestore(pa_lock, flags); } void __init __free_pages_bootmem(struct page *page, unsigned int order) @@ -1251,16 +1289,18 @@ void drain_zone_pages(struct zone *zone, struct per_cpu_pages *pcp) { unsigned long flags; + LIST_HEAD(dst); int to_drain, batch; - local_irq_save(flags); + local_lock_irqsave(pa_lock, flags); batch = ACCESS_ONCE(pcp->batch); to_drain = min(pcp->count, batch); if (to_drain > 0) { - free_pcppages_bulk(zone, to_drain, pcp); + isolate_pcp_pages(to_drain, pcp, &dst); pcp->count -= to_drain; } - local_irq_restore(flags); + local_unlock_irqrestore(pa_lock, flags); + free_pcppages_bulk(zone, to_drain, &dst); } #endif @@ -1279,16 +1319,21 @@ for_each_populated_zone(zone) { struct per_cpu_pageset *pset; struct per_cpu_pages *pcp; + LIST_HEAD(dst); + int count; - local_irq_save(flags); + cpu_lock_irqsave(cpu, flags); pset = per_cpu_ptr(zone->pageset, cpu); pcp = &pset->pcp; - if (pcp->count) { - free_pcppages_bulk(zone, pcp->count, pcp); + count = pcp->count; + if (count) { + isolate_pcp_pages(count, pcp, &dst); pcp->count = 0; } - local_irq_restore(flags); + cpu_unlock_irqrestore(cpu, flags); + if (count) + free_pcppages_bulk(zone, count, &dst); } } @@ -1341,7 +1386,12 @@ else cpumask_clear_cpu(cpu, &cpus_with_pcps); } +#ifndef CONFIG_PREEMPT_RT_BASE on_each_cpu_mask(&cpus_with_pcps, drain_local_pages, NULL, 1); +#else + for_each_cpu(cpu, &cpus_with_pcps) + drain_pages(cpu); +#endif } #ifdef CONFIG_HIBERNATION @@ -1397,7 +1447,7 @@ migratetype = get_pfnblock_migratetype(page, pfn); set_freepage_migratetype(page, migratetype); - local_irq_save(flags); + local_lock_irqsave(pa_lock, flags); __count_vm_event(PGFREE); /* @@ -1423,12 +1473,17 @@ pcp->count++; if (pcp->count >= pcp->high) { unsigned long batch = ACCESS_ONCE(pcp->batch); - free_pcppages_bulk(zone, batch, pcp); + LIST_HEAD(dst); + + isolate_pcp_pages(batch, pcp, &dst); pcp->count -= batch; + local_unlock_irqrestore(pa_lock, flags); + free_pcppages_bulk(zone, batch, &dst); + return; } out: - local_irq_restore(flags); + local_unlock_irqrestore(pa_lock, flags); } /* @@ -1558,7 +1613,7 @@ struct per_cpu_pages *pcp; struct list_head *list; - local_irq_save(flags); + local_lock_irqsave(pa_lock, flags); pcp = &this_cpu_ptr(zone->pageset)->pcp; list = &pcp->lists[migratetype]; if (list_empty(list)) { @@ -1590,13 +1645,15 @@ */ WARN_ON_ONCE(order > 1); } - spin_lock_irqsave(&zone->lock, flags); + local_spin_lock_irqsave(pa_lock, &zone->lock, flags); page = __rmqueue(zone, order, migratetype); - spin_unlock(&zone->lock); - if (!page) + if (!page) { + spin_unlock(&zone->lock); goto failed; + } __mod_zone_freepage_state(zone, -(1 << order), get_freepage_migratetype(page)); + spin_unlock(&zone->lock); } __mod_zone_page_state(zone, NR_ALLOC_BATCH, -(1 << order)); @@ -1606,7 +1663,7 @@ __count_zone_vm_events(PGALLOC, zone, 1 << order); zone_statistics(preferred_zone, zone, gfp_flags); - local_irq_restore(flags); + local_unlock_irqrestore(pa_lock, flags); VM_BUG_ON_PAGE(bad_range(zone, page), page); if (prep_new_page(page, order, gfp_flags)) @@ -1614,7 +1671,7 @@ return page; failed: - local_irq_restore(flags); + local_unlock_irqrestore(pa_lock, flags); return NULL; } @@ -2325,8 +2382,8 @@ count_vm_event(COMPACTSTALL); /* Page migration frees to the PCP lists but we want merging */ - drain_pages(get_cpu()); - put_cpu(); + drain_pages(get_cpu_light()); + put_cpu_light(); page = get_page_from_freelist(gfp_mask, nodemask, order, zonelist, high_zoneidx, @@ -5565,6 +5622,7 @@ void __init page_alloc_init(void) { hotcpu_notifier(page_alloc_cpu_notify, 0); + local_irq_lock_init(pa_lock); } /* @@ -6459,7 +6517,7 @@ struct per_cpu_pageset *pset; /* avoid races with drain_pages() */ - local_irq_save(flags); + local_lock_irqsave(pa_lock, flags); if (zone->pageset != &boot_pageset) { for_each_online_cpu(cpu) { pset = per_cpu_ptr(zone->pageset, cpu); @@ -6468,7 +6526,7 @@ free_percpu(zone->pageset); zone->pageset = &boot_pageset; } - local_irq_restore(flags); + local_unlock_irqrestore(pa_lock, flags); } #ifdef CONFIG_MEMORY_HOTREMOVE diff -Nur linux-3.18.14.orig/mm/slab.h linux-3.18.14-rt/mm/slab.h --- linux-3.18.14.orig/mm/slab.h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/mm/slab.h 2015-05-31 15:32:49.257635359 -0500 @@ -315,7 +315,11 @@ * The slab lists for all objects. */ struct kmem_cache_node { +#ifdef CONFIG_SLUB + raw_spinlock_t list_lock; +#else spinlock_t list_lock; +#endif #ifdef CONFIG_SLAB struct list_head slabs_partial; /* partial list first, better asm code */ diff -Nur linux-3.18.14.orig/mm/slub.c linux-3.18.14-rt/mm/slub.c --- linux-3.18.14.orig/mm/slub.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/mm/slub.c 2015-05-31 15:32:49.257635359 -0500 @@ -1044,7 +1044,7 @@ { struct kmem_cache_node *n = get_node(s, page_to_nid(page)); - spin_lock_irqsave(&n->list_lock, *flags); + raw_spin_lock_irqsave(&n->list_lock, *flags); slab_lock(page); if (!check_slab(s, page)) @@ -1091,7 +1091,7 @@ fail: slab_unlock(page); - spin_unlock_irqrestore(&n->list_lock, *flags); + raw_spin_unlock_irqrestore(&n->list_lock, *flags); slab_fix(s, "Object at 0x%p not freed", object); return NULL; } @@ -1219,6 +1219,12 @@ #endif /* CONFIG_SLUB_DEBUG */ +struct slub_free_list { + raw_spinlock_t lock; + struct list_head list; +}; +static DEFINE_PER_CPU(struct slub_free_list, slub_free_list); + /* * Hooks for other subsystems that check memory allocations. In a typical * production configuration these hooks all should produce no code at all. @@ -1303,10 +1309,15 @@ struct page *page; struct kmem_cache_order_objects oo = s->oo; gfp_t alloc_gfp; + bool enableirqs; flags &= gfp_allowed_mask; - if (flags & __GFP_WAIT) + enableirqs = (flags & __GFP_WAIT) != 0; +#ifdef CONFIG_PREEMPT_RT_FULL + enableirqs |= system_state == SYSTEM_RUNNING; +#endif + if (enableirqs) local_irq_enable(); flags |= s->allocflags; @@ -1347,7 +1358,7 @@ kmemcheck_mark_unallocated_pages(page, pages); } - if (flags & __GFP_WAIT) + if (enableirqs) local_irq_disable(); if (!page) return NULL; @@ -1365,8 +1376,10 @@ void *object) { setup_object_debug(s, page, object); +#ifndef CONFIG_PREEMPT_RT_FULL if (unlikely(s->ctor)) s->ctor(object); +#endif } static struct page *new_slab(struct kmem_cache *s, gfp_t flags, int node) @@ -1442,6 +1455,16 @@ memcg_uncharge_slab(s, order); } +static void free_delayed(struct list_head *h) +{ + while(!list_empty(h)) { + struct page *page = list_first_entry(h, struct page, lru); + + list_del(&page->lru); + __free_slab(page->slab_cache, page); + } +} + #define need_reserve_slab_rcu \ (sizeof(((struct page *)NULL)->lru) < sizeof(struct rcu_head)) @@ -1476,6 +1499,12 @@ } call_rcu(head, rcu_free_slab); + } else if (irqs_disabled()) { + struct slub_free_list *f = &__get_cpu_var(slub_free_list); + + raw_spin_lock(&f->lock); + list_add(&page->lru, &f->list); + raw_spin_unlock(&f->lock); } else __free_slab(s, page); } @@ -1589,7 +1618,7 @@ if (!n || !n->nr_partial) return NULL; - spin_lock(&n->list_lock); + raw_spin_lock(&n->list_lock); list_for_each_entry_safe(page, page2, &n->partial, lru) { void *t; @@ -1614,7 +1643,7 @@ break; } - spin_unlock(&n->list_lock); + raw_spin_unlock(&n->list_lock); return object; } @@ -1860,7 +1889,7 @@ * that acquire_slab() will see a slab page that * is frozen */ - spin_lock(&n->list_lock); + raw_spin_lock(&n->list_lock); } } else { m = M_FULL; @@ -1871,7 +1900,7 @@ * slabs from diagnostic functions will not see * any frozen slabs. */ - spin_lock(&n->list_lock); + raw_spin_lock(&n->list_lock); } } @@ -1906,7 +1935,7 @@ goto redo; if (lock) - spin_unlock(&n->list_lock); + raw_spin_unlock(&n->list_lock); if (m == M_FREE) { stat(s, DEACTIVATE_EMPTY); @@ -1938,10 +1967,10 @@ n2 = get_node(s, page_to_nid(page)); if (n != n2) { if (n) - spin_unlock(&n->list_lock); + raw_spin_unlock(&n->list_lock); n = n2; - spin_lock(&n->list_lock); + raw_spin_lock(&n->list_lock); } do { @@ -1970,7 +1999,7 @@ } if (n) - spin_unlock(&n->list_lock); + raw_spin_unlock(&n->list_lock); while (discard_page) { page = discard_page; @@ -2008,14 +2037,21 @@ pobjects = oldpage->pobjects; pages = oldpage->pages; if (drain && pobjects > s->cpu_partial) { + struct slub_free_list *f; unsigned long flags; + LIST_HEAD(tofree); /* * partial array is full. Move the existing * set to the per node partial list. */ local_irq_save(flags); unfreeze_partials(s, this_cpu_ptr(s->cpu_slab)); + f = &__get_cpu_var(slub_free_list); + raw_spin_lock(&f->lock); + list_splice_init(&f->list, &tofree); + raw_spin_unlock(&f->lock); local_irq_restore(flags); + free_delayed(&tofree); oldpage = NULL; pobjects = 0; pages = 0; @@ -2079,7 +2115,22 @@ static void flush_all(struct kmem_cache *s) { + LIST_HEAD(tofree); + int cpu; + on_each_cpu_cond(has_cpu_slab, flush_cpu_slab, s, 1, GFP_ATOMIC); + for_each_online_cpu(cpu) { + struct slub_free_list *f; + + if (!has_cpu_slab(cpu, s)) + continue; + + f = &per_cpu(slub_free_list, cpu); + raw_spin_lock_irq(&f->lock); + list_splice_init(&f->list, &tofree); + raw_spin_unlock_irq(&f->lock); + free_delayed(&tofree); + } } /* @@ -2115,10 +2166,10 @@ unsigned long x = 0; struct page *page; - spin_lock_irqsave(&n->list_lock, flags); + raw_spin_lock_irqsave(&n->list_lock, flags); list_for_each_entry(page, &n->partial, lru) x += get_count(page); - spin_unlock_irqrestore(&n->list_lock, flags); + raw_spin_unlock_irqrestore(&n->list_lock, flags); return x; } #endif /* CONFIG_SLUB_DEBUG || CONFIG_SYSFS */ @@ -2255,9 +2306,11 @@ static void *__slab_alloc(struct kmem_cache *s, gfp_t gfpflags, int node, unsigned long addr, struct kmem_cache_cpu *c) { + struct slub_free_list *f; void *freelist; struct page *page; unsigned long flags; + LIST_HEAD(tofree); local_irq_save(flags); #ifdef CONFIG_PREEMPT @@ -2325,7 +2378,13 @@ VM_BUG_ON(!c->page->frozen); c->freelist = get_freepointer(s, freelist); c->tid = next_tid(c->tid); +out: + f = &__get_cpu_var(slub_free_list); + raw_spin_lock(&f->lock); + list_splice_init(&f->list, &tofree); + raw_spin_unlock(&f->lock); local_irq_restore(flags); + free_delayed(&tofree); return freelist; new_slab: @@ -2342,8 +2401,7 @@ if (unlikely(!freelist)) { slab_out_of_memory(s, gfpflags, node); - local_irq_restore(flags); - return NULL; + goto out; } page = c->page; @@ -2358,8 +2416,7 @@ deactivate_slab(s, page, get_freepointer(s, freelist)); c->page = NULL; c->freelist = NULL; - local_irq_restore(flags); - return freelist; + goto out; } /* @@ -2444,6 +2501,10 @@ if (unlikely(gfpflags & __GFP_ZERO) && object) memset(object, 0, s->object_size); +#ifdef CONFIG_PREEMPT_RT_FULL + if (unlikely(s->ctor) && object) + s->ctor(object); +#endif slab_post_alloc_hook(s, gfpflags, object); @@ -2531,7 +2592,7 @@ do { if (unlikely(n)) { - spin_unlock_irqrestore(&n->list_lock, flags); + raw_spin_unlock_irqrestore(&n->list_lock, flags); n = NULL; } prior = page->freelist; @@ -2563,7 +2624,7 @@ * Otherwise the list_lock will synchronize with * other processors updating the list of slabs. */ - spin_lock_irqsave(&n->list_lock, flags); + raw_spin_lock_irqsave(&n->list_lock, flags); } } @@ -2605,7 +2666,7 @@ add_partial(n, page, DEACTIVATE_TO_TAIL); stat(s, FREE_ADD_PARTIAL); } - spin_unlock_irqrestore(&n->list_lock, flags); + raw_spin_unlock_irqrestore(&n->list_lock, flags); return; slab_empty: @@ -2620,7 +2681,7 @@ remove_full(s, n, page); } - spin_unlock_irqrestore(&n->list_lock, flags); + raw_spin_unlock_irqrestore(&n->list_lock, flags); stat(s, FREE_SLAB); discard_slab(s, page); } @@ -2816,7 +2877,7 @@ init_kmem_cache_node(struct kmem_cache_node *n) { n->nr_partial = 0; - spin_lock_init(&n->list_lock); + raw_spin_lock_init(&n->list_lock); INIT_LIST_HEAD(&n->partial); #ifdef CONFIG_SLUB_DEBUG atomic_long_set(&n->nr_slabs, 0); @@ -3373,7 +3434,7 @@ for (i = 0; i < objects; i++) INIT_LIST_HEAD(slabs_by_inuse + i); - spin_lock_irqsave(&n->list_lock, flags); + raw_spin_lock_irqsave(&n->list_lock, flags); /* * Build lists indexed by the items in use in each slab. @@ -3394,7 +3455,7 @@ for (i = objects - 1; i > 0; i--) list_splice(slabs_by_inuse + i, n->partial.prev); - spin_unlock_irqrestore(&n->list_lock, flags); + raw_spin_unlock_irqrestore(&n->list_lock, flags); /* Release empty slabs */ list_for_each_entry_safe(page, t, slabs_by_inuse, lru) @@ -3567,6 +3628,12 @@ { static __initdata struct kmem_cache boot_kmem_cache, boot_kmem_cache_node; + int cpu; + + for_each_possible_cpu(cpu) { + raw_spin_lock_init(&per_cpu(slub_free_list, cpu).lock); + INIT_LIST_HEAD(&per_cpu(slub_free_list, cpu).list); + } if (debug_guardpage_minorder()) slub_max_order = 0; @@ -3815,7 +3882,7 @@ struct page *page; unsigned long flags; - spin_lock_irqsave(&n->list_lock, flags); + raw_spin_lock_irqsave(&n->list_lock, flags); list_for_each_entry(page, &n->partial, lru) { validate_slab_slab(s, page, map); @@ -3837,7 +3904,7 @@ s->name, count, atomic_long_read(&n->nr_slabs)); out: - spin_unlock_irqrestore(&n->list_lock, flags); + raw_spin_unlock_irqrestore(&n->list_lock, flags); return count; } @@ -4025,12 +4092,12 @@ if (!atomic_long_read(&n->nr_slabs)) continue; - spin_lock_irqsave(&n->list_lock, flags); + raw_spin_lock_irqsave(&n->list_lock, flags); list_for_each_entry(page, &n->partial, lru) process_slab(&t, s, page, alloc, map); list_for_each_entry(page, &n->full, lru) process_slab(&t, s, page, alloc, map); - spin_unlock_irqrestore(&n->list_lock, flags); + raw_spin_unlock_irqrestore(&n->list_lock, flags); } for (i = 0; i < t.count; i++) { diff -Nur linux-3.18.14.orig/mm/swap.c linux-3.18.14-rt/mm/swap.c --- linux-3.18.14.orig/mm/swap.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/mm/swap.c 2015-05-31 15:32:49.285635359 -0500 @@ -31,6 +31,7 @@ #include #include #include +#include #include "internal.h" @@ -44,6 +45,9 @@ static DEFINE_PER_CPU(struct pagevec, lru_rotate_pvecs); static DEFINE_PER_CPU(struct pagevec, lru_deactivate_pvecs); +static DEFINE_LOCAL_IRQ_LOCK(rotate_lock); +static DEFINE_LOCAL_IRQ_LOCK(swapvec_lock); + /* * This path almost never happens for VM activity - pages are normally * freed via pagevecs. But it gets used by networking. @@ -473,11 +477,11 @@ unsigned long flags; page_cache_get(page); - local_irq_save(flags); + local_lock_irqsave(rotate_lock, flags); pvec = this_cpu_ptr(&lru_rotate_pvecs); if (!pagevec_add(pvec, page)) pagevec_move_tail(pvec); - local_irq_restore(flags); + local_unlock_irqrestore(rotate_lock, flags); } } @@ -528,12 +532,13 @@ void activate_page(struct page *page) { if (PageLRU(page) && !PageActive(page) && !PageUnevictable(page)) { - struct pagevec *pvec = &get_cpu_var(activate_page_pvecs); + struct pagevec *pvec = &get_locked_var(swapvec_lock, + activate_page_pvecs); page_cache_get(page); if (!pagevec_add(pvec, page)) pagevec_lru_move_fn(pvec, __activate_page, NULL); - put_cpu_var(activate_page_pvecs); + put_locked_var(swapvec_lock, activate_page_pvecs); } } @@ -559,7 +564,7 @@ static void __lru_cache_activate_page(struct page *page) { - struct pagevec *pvec = &get_cpu_var(lru_add_pvec); + struct pagevec *pvec = &get_locked_var(swapvec_lock, lru_add_pvec); int i; /* @@ -581,7 +586,7 @@ } } - put_cpu_var(lru_add_pvec); + put_locked_var(swapvec_lock, lru_add_pvec); } /* @@ -620,13 +625,13 @@ static void __lru_cache_add(struct page *page) { - struct pagevec *pvec = &get_cpu_var(lru_add_pvec); + struct pagevec *pvec = &get_locked_var(swapvec_lock, lru_add_pvec); page_cache_get(page); if (!pagevec_space(pvec)) __pagevec_lru_add(pvec); pagevec_add(pvec, page); - put_cpu_var(lru_add_pvec); + put_locked_var(swapvec_lock, lru_add_pvec); } /** @@ -806,9 +811,9 @@ unsigned long flags; /* No harm done if a racing interrupt already did this */ - local_irq_save(flags); + local_lock_irqsave(rotate_lock, flags); pagevec_move_tail(pvec); - local_irq_restore(flags); + local_unlock_irqrestore(rotate_lock, flags); } pvec = &per_cpu(lru_deactivate_pvecs, cpu); @@ -836,18 +841,19 @@ return; if (likely(get_page_unless_zero(page))) { - struct pagevec *pvec = &get_cpu_var(lru_deactivate_pvecs); + struct pagevec *pvec = &get_locked_var(swapvec_lock, + lru_deactivate_pvecs); if (!pagevec_add(pvec, page)) pagevec_lru_move_fn(pvec, lru_deactivate_fn, NULL); - put_cpu_var(lru_deactivate_pvecs); + put_locked_var(swapvec_lock, lru_deactivate_pvecs); } } void lru_add_drain(void) { - lru_add_drain_cpu(get_cpu()); - put_cpu(); + lru_add_drain_cpu(local_lock_cpu(swapvec_lock)); + local_unlock_cpu(swapvec_lock); } static void lru_add_drain_per_cpu(struct work_struct *dummy) diff -Nur linux-3.18.14.orig/mm/truncate.c linux-3.18.14-rt/mm/truncate.c --- linux-3.18.14.orig/mm/truncate.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/mm/truncate.c 2015-05-31 15:32:49.293635359 -0500 @@ -56,8 +56,11 @@ * protected by mapping->tree_lock. */ if (!workingset_node_shadows(node) && - !list_empty(&node->private_list)) - list_lru_del(&workingset_shadow_nodes, &node->private_list); + !list_empty(&node->private_list)) { + local_lock(workingset_shadow_lock); + list_lru_del(&__workingset_shadow_nodes, &node->private_list); + local_unlock(workingset_shadow_lock); + } __radix_tree_delete_node(&mapping->page_tree, node); unlock: spin_unlock_irq(&mapping->tree_lock); diff -Nur linux-3.18.14.orig/mm/vmalloc.c linux-3.18.14-rt/mm/vmalloc.c --- linux-3.18.14.orig/mm/vmalloc.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/mm/vmalloc.c 2015-05-31 15:32:49.297635359 -0500 @@ -798,7 +798,7 @@ struct vmap_block *vb; struct vmap_area *va; unsigned long vb_idx; - int node, err; + int node, err, cpu; node = numa_node_id(); @@ -836,11 +836,12 @@ BUG_ON(err); radix_tree_preload_end(); - vbq = &get_cpu_var(vmap_block_queue); + cpu = get_cpu_light(); + vbq = &__get_cpu_var(vmap_block_queue); spin_lock(&vbq->lock); list_add_rcu(&vb->free_list, &vbq->free); spin_unlock(&vbq->lock); - put_cpu_var(vmap_block_queue); + put_cpu_light(); return vb; } @@ -908,6 +909,7 @@ struct vmap_block *vb; unsigned long addr = 0; unsigned int order; + int cpu = 0; BUG_ON(size & ~PAGE_MASK); BUG_ON(size > PAGE_SIZE*VMAP_MAX_ALLOC); @@ -923,7 +925,8 @@ again: rcu_read_lock(); - vbq = &get_cpu_var(vmap_block_queue); + cpu = get_cpu_light(); + vbq = &__get_cpu_var(vmap_block_queue); list_for_each_entry_rcu(vb, &vbq->free, free_list) { int i; @@ -947,7 +950,7 @@ spin_unlock(&vb->lock); } - put_cpu_var(vmap_block_queue); + put_cpu_light(); rcu_read_unlock(); if (!addr) { diff -Nur linux-3.18.14.orig/mm/vmstat.c linux-3.18.14-rt/mm/vmstat.c --- linux-3.18.14.orig/mm/vmstat.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/mm/vmstat.c 2015-05-31 15:32:49.297635359 -0500 @@ -221,6 +221,7 @@ long x; long t; + preempt_disable_rt(); x = delta + __this_cpu_read(*p); t = __this_cpu_read(pcp->stat_threshold); @@ -230,6 +231,7 @@ x = 0; } __this_cpu_write(*p, x); + preempt_enable_rt(); } EXPORT_SYMBOL(__mod_zone_page_state); @@ -262,6 +264,7 @@ s8 __percpu *p = pcp->vm_stat_diff + item; s8 v, t; + preempt_disable_rt(); v = __this_cpu_inc_return(*p); t = __this_cpu_read(pcp->stat_threshold); if (unlikely(v > t)) { @@ -270,6 +273,7 @@ zone_page_state_add(v + overstep, zone, item); __this_cpu_write(*p, -overstep); } + preempt_enable_rt(); } void __inc_zone_page_state(struct page *page, enum zone_stat_item item) @@ -284,6 +288,7 @@ s8 __percpu *p = pcp->vm_stat_diff + item; s8 v, t; + preempt_disable_rt(); v = __this_cpu_dec_return(*p); t = __this_cpu_read(pcp->stat_threshold); if (unlikely(v < - t)) { @@ -292,6 +297,7 @@ zone_page_state_add(v - overstep, zone, item); __this_cpu_write(*p, overstep); } + preempt_enable_rt(); } void __dec_zone_page_state(struct page *page, enum zone_stat_item item) diff -Nur linux-3.18.14.orig/mm/workingset.c linux-3.18.14-rt/mm/workingset.c --- linux-3.18.14.orig/mm/workingset.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/mm/workingset.c 2015-05-31 15:32:49.321635359 -0500 @@ -264,7 +264,8 @@ * point where they would still be useful. */ -struct list_lru workingset_shadow_nodes; +struct list_lru __workingset_shadow_nodes; +DEFINE_LOCAL_IRQ_LOCK(workingset_shadow_lock); static unsigned long count_shadow_nodes(struct shrinker *shrinker, struct shrink_control *sc) @@ -274,9 +275,9 @@ unsigned long pages; /* list_lru lock nests inside IRQ-safe mapping->tree_lock */ - local_irq_disable(); - shadow_nodes = list_lru_count_node(&workingset_shadow_nodes, sc->nid); - local_irq_enable(); + local_lock_irq(workingset_shadow_lock); + shadow_nodes = list_lru_count_node(&__workingset_shadow_nodes, sc->nid); + local_unlock_irq(workingset_shadow_lock); pages = node_present_pages(sc->nid); /* @@ -362,9 +363,9 @@ spin_unlock(&mapping->tree_lock); ret = LRU_REMOVED_RETRY; out: - local_irq_enable(); + local_unlock_irq(workingset_shadow_lock); cond_resched(); - local_irq_disable(); + local_lock_irq(workingset_shadow_lock); spin_lock(lru_lock); return ret; } @@ -375,10 +376,10 @@ unsigned long ret; /* list_lru lock nests inside IRQ-safe mapping->tree_lock */ - local_irq_disable(); - ret = list_lru_walk_node(&workingset_shadow_nodes, sc->nid, + local_lock_irq(workingset_shadow_lock); + ret = list_lru_walk_node(&__workingset_shadow_nodes, sc->nid, shadow_lru_isolate, NULL, &sc->nr_to_scan); - local_irq_enable(); + local_unlock_irq(workingset_shadow_lock); return ret; } @@ -399,7 +400,7 @@ { int ret; - ret = list_lru_init_key(&workingset_shadow_nodes, &shadow_nodes_key); + ret = list_lru_init_key(&__workingset_shadow_nodes, &shadow_nodes_key); if (ret) goto err; ret = register_shrinker(&workingset_shadow_shrinker); @@ -407,7 +408,7 @@ goto err_list_lru; return 0; err_list_lru: - list_lru_destroy(&workingset_shadow_nodes); + list_lru_destroy(&__workingset_shadow_nodes); err: return ret; } diff -Nur linux-3.18.14.orig/net/core/dev.c linux-3.18.14-rt/net/core/dev.c --- linux-3.18.14.orig/net/core/dev.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/net/core/dev.c 2015-05-31 15:32:49.369635359 -0500 @@ -182,6 +182,7 @@ static DEFINE_HASHTABLE(napi_hash, 8); static seqcount_t devnet_rename_seq; +static DEFINE_MUTEX(devnet_rename_mutex); static inline void dev_base_seq_inc(struct net *net) { @@ -203,14 +204,14 @@ static inline void rps_lock(struct softnet_data *sd) { #ifdef CONFIG_RPS - spin_lock(&sd->input_pkt_queue.lock); + raw_spin_lock(&sd->input_pkt_queue.raw_lock); #endif } static inline void rps_unlock(struct softnet_data *sd) { #ifdef CONFIG_RPS - spin_unlock(&sd->input_pkt_queue.lock); + raw_spin_unlock(&sd->input_pkt_queue.raw_lock); #endif } @@ -832,7 +833,8 @@ strcpy(name, dev->name); rcu_read_unlock(); if (read_seqcount_retry(&devnet_rename_seq, seq)) { - cond_resched(); + mutex_lock(&devnet_rename_mutex); + mutex_unlock(&devnet_rename_mutex); goto retry; } @@ -1101,20 +1103,17 @@ if (dev->flags & IFF_UP) return -EBUSY; - write_seqcount_begin(&devnet_rename_seq); + mutex_lock(&devnet_rename_mutex); + __raw_write_seqcount_begin(&devnet_rename_seq); - if (strncmp(newname, dev->name, IFNAMSIZ) == 0) { - write_seqcount_end(&devnet_rename_seq); - return 0; - } + if (strncmp(newname, dev->name, IFNAMSIZ) == 0) + goto outunlock; memcpy(oldname, dev->name, IFNAMSIZ); err = dev_get_valid_name(net, dev, newname); - if (err < 0) { - write_seqcount_end(&devnet_rename_seq); - return err; - } + if (err < 0) + goto outunlock; if (oldname[0] && !strchr(oldname, '%')) netdev_info(dev, "renamed from %s\n", oldname); @@ -1127,11 +1126,12 @@ if (ret) { memcpy(dev->name, oldname, IFNAMSIZ); dev->name_assign_type = old_assign_type; - write_seqcount_end(&devnet_rename_seq); - return ret; + err = ret; + goto outunlock; } - write_seqcount_end(&devnet_rename_seq); + __raw_write_seqcount_end(&devnet_rename_seq); + mutex_unlock(&devnet_rename_mutex); netdev_adjacent_rename_links(dev, oldname); @@ -1152,7 +1152,8 @@ /* err >= 0 after dev_alloc_name() or stores the first errno */ if (err >= 0) { err = ret; - write_seqcount_begin(&devnet_rename_seq); + mutex_lock(&devnet_rename_mutex); + __raw_write_seqcount_begin(&devnet_rename_seq); memcpy(dev->name, oldname, IFNAMSIZ); memcpy(oldname, newname, IFNAMSIZ); dev->name_assign_type = old_assign_type; @@ -1165,6 +1166,11 @@ } return err; + +outunlock: + __raw_write_seqcount_end(&devnet_rename_seq); + mutex_unlock(&devnet_rename_mutex); + return err; } /** @@ -2160,6 +2166,7 @@ sd->output_queue_tailp = &q->next_sched; raise_softirq_irqoff(NET_TX_SOFTIRQ); local_irq_restore(flags); + preempt_check_resched_rt(); } void __netif_schedule(struct Qdisc *q) @@ -2241,6 +2248,7 @@ __this_cpu_write(softnet_data.completion_queue, skb); raise_softirq_irqoff(NET_TX_SOFTIRQ); local_irq_restore(flags); + preempt_check_resched_rt(); } EXPORT_SYMBOL(__dev_kfree_skb_irq); @@ -3334,6 +3342,7 @@ rps_unlock(sd); local_irq_restore(flags); + preempt_check_resched_rt(); atomic_long_inc(&skb->dev->rx_dropped); kfree_skb(skb); @@ -3352,7 +3361,7 @@ struct rps_dev_flow voidflow, *rflow = &voidflow; int cpu; - preempt_disable(); + migrate_disable(); rcu_read_lock(); cpu = get_rps_cpu(skb->dev, skb, &rflow); @@ -3362,13 +3371,13 @@ ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail); rcu_read_unlock(); - preempt_enable(); + migrate_enable(); } else #endif { unsigned int qtail; - ret = enqueue_to_backlog(skb, get_cpu(), &qtail); - put_cpu(); + ret = enqueue_to_backlog(skb, get_cpu_light(), &qtail); + put_cpu_light(); } return ret; } @@ -3402,16 +3411,44 @@ trace_netif_rx_ni_entry(skb); - preempt_disable(); + local_bh_disable(); err = netif_rx_internal(skb); - if (local_softirq_pending()) - do_softirq(); - preempt_enable(); + local_bh_enable(); return err; } EXPORT_SYMBOL(netif_rx_ni); +#ifdef CONFIG_PREEMPT_RT_FULL +/* + * RT runs ksoftirqd as a real time thread and the root_lock is a + * "sleeping spinlock". If the trylock fails then we can go into an + * infinite loop when ksoftirqd preempted the task which actually + * holds the lock, because we requeue q and raise NET_TX softirq + * causing ksoftirqd to loop forever. + * + * It's safe to use spin_lock on RT here as softirqs run in thread + * context and cannot deadlock against the thread which is holding + * root_lock. + * + * On !RT the trylock might fail, but there we bail out from the + * softirq loop after 10 attempts which we can't do on RT. And the + * task holding root_lock cannot be preempted, so the only downside of + * that trylock is that we need 10 loops to decide that we should have + * given up in the first one :) + */ +static inline int take_root_lock(spinlock_t *lock) +{ + spin_lock(lock); + return 1; +} +#else +static inline int take_root_lock(spinlock_t *lock) +{ + return spin_trylock(lock); +} +#endif + static void net_tx_action(struct softirq_action *h) { struct softnet_data *sd = this_cpu_ptr(&softnet_data); @@ -3453,7 +3490,7 @@ head = head->next_sched; root_lock = qdisc_lock(q); - if (spin_trylock(root_lock)) { + if (take_root_lock(root_lock)) { smp_mb__before_atomic(); clear_bit(__QDISC_STATE_SCHED, &q->state); @@ -3846,7 +3883,7 @@ skb_queue_walk_safe(&sd->input_pkt_queue, skb, tmp) { if (skb->dev == dev) { __skb_unlink(skb, &sd->input_pkt_queue); - kfree_skb(skb); + __skb_queue_tail(&sd->tofree_queue, skb); input_queue_head_incr(sd); } } @@ -3855,10 +3892,13 @@ skb_queue_walk_safe(&sd->process_queue, skb, tmp) { if (skb->dev == dev) { __skb_unlink(skb, &sd->process_queue); - kfree_skb(skb); + __skb_queue_tail(&sd->tofree_queue, skb); input_queue_head_incr(sd); } } + + if (!skb_queue_empty(&sd->tofree_queue)) + raise_softirq_irqoff(NET_RX_SOFTIRQ); } static int napi_gro_complete(struct sk_buff *skb) @@ -4321,6 +4361,7 @@ } else #endif local_irq_enable(); + preempt_check_resched_rt(); } static int process_backlog(struct napi_struct *napi, int quota) @@ -4392,6 +4433,7 @@ local_irq_save(flags); ____napi_schedule(this_cpu_ptr(&softnet_data), n); local_irq_restore(flags); + preempt_check_resched_rt(); } EXPORT_SYMBOL(__napi_schedule); @@ -4514,10 +4556,17 @@ struct softnet_data *sd = this_cpu_ptr(&softnet_data); unsigned long time_limit = jiffies + 2; int budget = netdev_budget; + struct sk_buff *skb; void *have; local_irq_disable(); + while ((skb = __skb_dequeue(&sd->tofree_queue))) { + local_irq_enable(); + kfree_skb(skb); + local_irq_disable(); + } + while (!list_empty(&sd->poll_list)) { struct napi_struct *n; int work, weight; @@ -7006,6 +7055,7 @@ raise_softirq_irqoff(NET_TX_SOFTIRQ); local_irq_enable(); + preempt_check_resched_rt(); /* Process offline CPU's input_pkt_queue */ while ((skb = __skb_dequeue(&oldsd->process_queue))) { @@ -7016,6 +7066,9 @@ netif_rx_internal(skb); input_queue_head_incr(oldsd); } + while ((skb = __skb_dequeue(&oldsd->tofree_queue))) { + kfree_skb(skb); + } return NOTIFY_OK; } @@ -7317,8 +7370,9 @@ for_each_possible_cpu(i) { struct softnet_data *sd = &per_cpu(softnet_data, i); - skb_queue_head_init(&sd->input_pkt_queue); - skb_queue_head_init(&sd->process_queue); + skb_queue_head_init_raw(&sd->input_pkt_queue); + skb_queue_head_init_raw(&sd->process_queue); + skb_queue_head_init_raw(&sd->tofree_queue); INIT_LIST_HEAD(&sd->poll_list); sd->output_queue_tailp = &sd->output_queue; #ifdef CONFIG_RPS diff -Nur linux-3.18.14.orig/net/core/skbuff.c linux-3.18.14-rt/net/core/skbuff.c --- linux-3.18.14.orig/net/core/skbuff.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/net/core/skbuff.c 2015-05-31 15:32:49.393635358 -0500 @@ -63,6 +63,7 @@ #include #include #include +#include #include #include @@ -353,6 +354,7 @@ unsigned int pagecnt_bias; }; static DEFINE_PER_CPU(struct netdev_alloc_cache, netdev_alloc_cache); +static DEFINE_LOCAL_IRQ_LOCK(netdev_alloc_lock); static void *__netdev_alloc_frag(unsigned int fragsz, gfp_t gfp_mask) { @@ -361,7 +363,7 @@ int order; unsigned long flags; - local_irq_save(flags); + local_lock_irqsave(netdev_alloc_lock, flags); nc = this_cpu_ptr(&netdev_alloc_cache); if (unlikely(!nc->frag.page)) { refill: @@ -407,7 +409,7 @@ nc->frag.offset += fragsz; nc->pagecnt_bias--; end: - local_irq_restore(flags); + local_unlock_irqrestore(netdev_alloc_lock, flags); return data; } diff -Nur linux-3.18.14.orig/net/core/skbuff.c.orig linux-3.18.14-rt/net/core/skbuff.c.orig --- linux-3.18.14.orig/net/core/skbuff.c.orig 1969-12-31 18:00:00.000000000 -0600 +++ linux-3.18.14-rt/net/core/skbuff.c.orig 2015-05-20 10:04:50.000000000 -0500 @@ -0,0 +1,4231 @@ +/* + * Routines having to do with the 'struct sk_buff' memory handlers. + * + * Authors: Alan Cox + * Florian La Roche + * + * Fixes: + * Alan Cox : Fixed the worst of the load + * balancer bugs. + * Dave Platt : Interrupt stacking fix. + * Richard Kooijman : Timestamp fixes. + * Alan Cox : Changed buffer format. + * Alan Cox : destructor hook for AF_UNIX etc. + * Linus Torvalds : Better skb_clone. + * Alan Cox : Added skb_copy. + * Alan Cox : Added all the changed routines Linus + * only put in the headers + * Ray VanTassle : Fixed --skb->lock in free + * Alan Cox : skb_copy copy arp field + * Andi Kleen : slabified it. + * Robert Olsson : Removed skb_head_pool + * + * NOTE: + * The __skb_ routines should be called with interrupts + * disabled, or you better be *real* sure that the operation is atomic + * with respect to whatever list is being frobbed (e.g. via lock_sock() + * or via disabling bottom half handlers, etc). + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ + +/* + * The functions in this file will not compile correctly with gcc 2.4.x + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#ifdef CONFIG_NET_CLS_ACT +#include +#endif +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include +#include +#include +#include +#include + +#include +#include +#include + +struct kmem_cache *skbuff_head_cache __read_mostly; +static struct kmem_cache *skbuff_fclone_cache __read_mostly; + +/** + * skb_panic - private function for out-of-line support + * @skb: buffer + * @sz: size + * @addr: address + * @msg: skb_over_panic or skb_under_panic + * + * Out-of-line support for skb_put() and skb_push(). + * Called via the wrapper skb_over_panic() or skb_under_panic(). + * Keep out of line to prevent kernel bloat. + * __builtin_return_address is not used because it is not always reliable. + */ +static void skb_panic(struct sk_buff *skb, unsigned int sz, void *addr, + const char msg[]) +{ + pr_emerg("%s: text:%p len:%d put:%d head:%p data:%p tail:%#lx end:%#lx dev:%s\n", + msg, addr, skb->len, sz, skb->head, skb->data, + (unsigned long)skb->tail, (unsigned long)skb->end, + skb->dev ? skb->dev->name : ""); + BUG(); +} + +static void skb_over_panic(struct sk_buff *skb, unsigned int sz, void *addr) +{ + skb_panic(skb, sz, addr, __func__); +} + +static void skb_under_panic(struct sk_buff *skb, unsigned int sz, void *addr) +{ + skb_panic(skb, sz, addr, __func__); +} + +/* + * kmalloc_reserve is a wrapper around kmalloc_node_track_caller that tells + * the caller if emergency pfmemalloc reserves are being used. If it is and + * the socket is later found to be SOCK_MEMALLOC then PFMEMALLOC reserves + * may be used. Otherwise, the packet data may be discarded until enough + * memory is free + */ +#define kmalloc_reserve(size, gfp, node, pfmemalloc) \ + __kmalloc_reserve(size, gfp, node, _RET_IP_, pfmemalloc) + +static void *__kmalloc_reserve(size_t size, gfp_t flags, int node, + unsigned long ip, bool *pfmemalloc) +{ + void *obj; + bool ret_pfmemalloc = false; + + /* + * Try a regular allocation, when that fails and we're not entitled + * to the reserves, fail. + */ + obj = kmalloc_node_track_caller(size, + flags | __GFP_NOMEMALLOC | __GFP_NOWARN, + node); + if (obj || !(gfp_pfmemalloc_allowed(flags))) + goto out; + + /* Try again but now we are using pfmemalloc reserves */ + ret_pfmemalloc = true; + obj = kmalloc_node_track_caller(size, flags, node); + +out: + if (pfmemalloc) + *pfmemalloc = ret_pfmemalloc; + + return obj; +} + +/* Allocate a new skbuff. We do this ourselves so we can fill in a few + * 'private' fields and also do memory statistics to find all the + * [BEEP] leaks. + * + */ + +struct sk_buff *__alloc_skb_head(gfp_t gfp_mask, int node) +{ + struct sk_buff *skb; + + /* Get the HEAD */ + skb = kmem_cache_alloc_node(skbuff_head_cache, + gfp_mask & ~__GFP_DMA, node); + if (!skb) + goto out; + + /* + * Only clear those fields we need to clear, not those that we will + * actually initialise below. Hence, don't put any more fields after + * the tail pointer in struct sk_buff! + */ + memset(skb, 0, offsetof(struct sk_buff, tail)); + skb->head = NULL; + skb->truesize = sizeof(struct sk_buff); + atomic_set(&skb->users, 1); + + skb->mac_header = (typeof(skb->mac_header))~0U; +out: + return skb; +} + +/** + * __alloc_skb - allocate a network buffer + * @size: size to allocate + * @gfp_mask: allocation mask + * @flags: If SKB_ALLOC_FCLONE is set, allocate from fclone cache + * instead of head cache and allocate a cloned (child) skb. + * If SKB_ALLOC_RX is set, __GFP_MEMALLOC will be used for + * allocations in case the data is required for writeback + * @node: numa node to allocate memory on + * + * Allocate a new &sk_buff. The returned buffer has no headroom and a + * tail room of at least size bytes. The object has a reference count + * of one. The return is the buffer. On a failure the return is %NULL. + * + * Buffers may only be allocated from interrupts using a @gfp_mask of + * %GFP_ATOMIC. + */ +struct sk_buff *__alloc_skb(unsigned int size, gfp_t gfp_mask, + int flags, int node) +{ + struct kmem_cache *cache; + struct skb_shared_info *shinfo; + struct sk_buff *skb; + u8 *data; + bool pfmemalloc; + + cache = (flags & SKB_ALLOC_FCLONE) + ? skbuff_fclone_cache : skbuff_head_cache; + + if (sk_memalloc_socks() && (flags & SKB_ALLOC_RX)) + gfp_mask |= __GFP_MEMALLOC; + + /* Get the HEAD */ + skb = kmem_cache_alloc_node(cache, gfp_mask & ~__GFP_DMA, node); + if (!skb) + goto out; + prefetchw(skb); + + /* We do our best to align skb_shared_info on a separate cache + * line. It usually works because kmalloc(X > SMP_CACHE_BYTES) gives + * aligned memory blocks, unless SLUB/SLAB debug is enabled. + * Both skb->head and skb_shared_info are cache line aligned. + */ + size = SKB_DATA_ALIGN(size); + size += SKB_DATA_ALIGN(sizeof(struct skb_shared_info)); + data = kmalloc_reserve(size, gfp_mask, node, &pfmemalloc); + if (!data) + goto nodata; + /* kmalloc(size) might give us more room than requested. + * Put skb_shared_info exactly at the end of allocated zone, + * to allow max possible filling before reallocation. + */ + size = SKB_WITH_OVERHEAD(ksize(data)); + prefetchw(data + size); + + /* + * Only clear those fields we need to clear, not those that we will + * actually initialise below. Hence, don't put any more fields after + * the tail pointer in struct sk_buff! + */ + memset(skb, 0, offsetof(struct sk_buff, tail)); + /* Account for allocated memory : skb + skb->head */ + skb->truesize = SKB_TRUESIZE(size); + skb->pfmemalloc = pfmemalloc; + atomic_set(&skb->users, 1); + skb->head = data; + skb->data = data; + skb_reset_tail_pointer(skb); + skb->end = skb->tail + size; + skb->mac_header = (typeof(skb->mac_header))~0U; + skb->transport_header = (typeof(skb->transport_header))~0U; + + /* make sure we initialize shinfo sequentially */ + shinfo = skb_shinfo(skb); + memset(shinfo, 0, offsetof(struct skb_shared_info, dataref)); + atomic_set(&shinfo->dataref, 1); + kmemcheck_annotate_variable(shinfo->destructor_arg); + + if (flags & SKB_ALLOC_FCLONE) { + struct sk_buff_fclones *fclones; + + fclones = container_of(skb, struct sk_buff_fclones, skb1); + + kmemcheck_annotate_bitfield(&fclones->skb2, flags1); + skb->fclone = SKB_FCLONE_ORIG; + atomic_set(&fclones->fclone_ref, 1); + + fclones->skb2.fclone = SKB_FCLONE_FREE; + fclones->skb2.pfmemalloc = pfmemalloc; + } +out: + return skb; +nodata: + kmem_cache_free(cache, skb); + skb = NULL; + goto out; +} +EXPORT_SYMBOL(__alloc_skb); + +/** + * __build_skb - build a network buffer + * @data: data buffer provided by caller + * @frag_size: size of data, or 0 if head was kmalloced + * + * Allocate a new &sk_buff. Caller provides space holding head and + * skb_shared_info. @data must have been allocated by kmalloc() only if + * @frag_size is 0, otherwise data should come from the page allocator + * or vmalloc() + * The return is the new skb buffer. + * On a failure the return is %NULL, and @data is not freed. + * Notes : + * Before IO, driver allocates only data buffer where NIC put incoming frame + * Driver should add room at head (NET_SKB_PAD) and + * MUST add room at tail (SKB_DATA_ALIGN(skb_shared_info)) + * After IO, driver calls build_skb(), to allocate sk_buff and populate it + * before giving packet to stack. + * RX rings only contains data buffers, not full skbs. + */ +struct sk_buff *__build_skb(void *data, unsigned int frag_size) +{ + struct skb_shared_info *shinfo; + struct sk_buff *skb; + unsigned int size = frag_size ? : ksize(data); + + skb = kmem_cache_alloc(skbuff_head_cache, GFP_ATOMIC); + if (!skb) + return NULL; + + size -= SKB_DATA_ALIGN(sizeof(struct skb_shared_info)); + + memset(skb, 0, offsetof(struct sk_buff, tail)); + skb->truesize = SKB_TRUESIZE(size); + atomic_set(&skb->users, 1); + skb->head = data; + skb->data = data; + skb_reset_tail_pointer(skb); + skb->end = skb->tail + size; + skb->mac_header = (typeof(skb->mac_header))~0U; + skb->transport_header = (typeof(skb->transport_header))~0U; + + /* make sure we initialize shinfo sequentially */ + shinfo = skb_shinfo(skb); + memset(shinfo, 0, offsetof(struct skb_shared_info, dataref)); + atomic_set(&shinfo->dataref, 1); + kmemcheck_annotate_variable(shinfo->destructor_arg); + + return skb; +} + +/* build_skb() is wrapper over __build_skb(), that specifically + * takes care of skb->head and skb->pfmemalloc + * This means that if @frag_size is not zero, then @data must be backed + * by a page fragment, not kmalloc() or vmalloc() + */ +struct sk_buff *build_skb(void *data, unsigned int frag_size) +{ + struct sk_buff *skb = __build_skb(data, frag_size); + + if (skb && frag_size) { + skb->head_frag = 1; + if (virt_to_head_page(data)->pfmemalloc) + skb->pfmemalloc = 1; + } + return skb; +} +EXPORT_SYMBOL(build_skb); + +struct netdev_alloc_cache { + struct page_frag frag; + /* we maintain a pagecount bias, so that we dont dirty cache line + * containing page->_count every time we allocate a fragment. + */ + unsigned int pagecnt_bias; +}; +static DEFINE_PER_CPU(struct netdev_alloc_cache, netdev_alloc_cache); + +static void *__netdev_alloc_frag(unsigned int fragsz, gfp_t gfp_mask) +{ + struct netdev_alloc_cache *nc; + void *data = NULL; + int order; + unsigned long flags; + + local_irq_save(flags); + nc = this_cpu_ptr(&netdev_alloc_cache); + if (unlikely(!nc->frag.page)) { +refill: + for (order = NETDEV_FRAG_PAGE_MAX_ORDER; ;) { + gfp_t gfp = gfp_mask; + + if (order) + gfp |= __GFP_COMP | __GFP_NOWARN | + __GFP_NOMEMALLOC; + nc->frag.page = alloc_pages(gfp, order); + if (likely(nc->frag.page)) + break; + if (--order < 0) + goto end; + } + nc->frag.size = PAGE_SIZE << order; + /* Even if we own the page, we do not use atomic_set(). + * This would break get_page_unless_zero() users. + */ + atomic_add(NETDEV_PAGECNT_MAX_BIAS - 1, + &nc->frag.page->_count); + nc->pagecnt_bias = NETDEV_PAGECNT_MAX_BIAS; + nc->frag.offset = 0; + } + + if (nc->frag.offset + fragsz > nc->frag.size) { + if (atomic_read(&nc->frag.page->_count) != nc->pagecnt_bias) { + if (!atomic_sub_and_test(nc->pagecnt_bias, + &nc->frag.page->_count)) + goto refill; + /* OK, page count is 0, we can safely set it */ + atomic_set(&nc->frag.page->_count, + NETDEV_PAGECNT_MAX_BIAS); + } else { + atomic_add(NETDEV_PAGECNT_MAX_BIAS - nc->pagecnt_bias, + &nc->frag.page->_count); + } + nc->pagecnt_bias = NETDEV_PAGECNT_MAX_BIAS; + nc->frag.offset = 0; + } + + data = page_address(nc->frag.page) + nc->frag.offset; + nc->frag.offset += fragsz; + nc->pagecnt_bias--; +end: + local_irq_restore(flags); + return data; +} + +/** + * netdev_alloc_frag - allocate a page fragment + * @fragsz: fragment size + * + * Allocates a frag from a page for receive buffer. + * Uses GFP_ATOMIC allocations. + */ +void *netdev_alloc_frag(unsigned int fragsz) +{ + return __netdev_alloc_frag(fragsz, GFP_ATOMIC | __GFP_COLD); +} +EXPORT_SYMBOL(netdev_alloc_frag); + +/** + * __netdev_alloc_skb - allocate an skbuff for rx on a specific device + * @dev: network device to receive on + * @length: length to allocate + * @gfp_mask: get_free_pages mask, passed to alloc_skb + * + * Allocate a new &sk_buff and assign it a usage count of one. The + * buffer has unspecified headroom built in. Users should allocate + * the headroom they think they need without accounting for the + * built in space. The built in space is used for optimisations. + * + * %NULL is returned if there is no free memory. + */ +struct sk_buff *__netdev_alloc_skb(struct net_device *dev, + unsigned int length, gfp_t gfp_mask) +{ + struct sk_buff *skb = NULL; + unsigned int fragsz = SKB_DATA_ALIGN(length + NET_SKB_PAD) + + SKB_DATA_ALIGN(sizeof(struct skb_shared_info)); + + if (fragsz <= PAGE_SIZE && !(gfp_mask & (__GFP_WAIT | GFP_DMA))) { + void *data; + + if (sk_memalloc_socks()) + gfp_mask |= __GFP_MEMALLOC; + + data = __netdev_alloc_frag(fragsz, gfp_mask); + + if (likely(data)) { + skb = build_skb(data, fragsz); + if (unlikely(!skb)) + put_page(virt_to_head_page(data)); + } + } else { + skb = __alloc_skb(length + NET_SKB_PAD, gfp_mask, + SKB_ALLOC_RX, NUMA_NO_NODE); + } + if (likely(skb)) { + skb_reserve(skb, NET_SKB_PAD); + skb->dev = dev; + } + return skb; +} +EXPORT_SYMBOL(__netdev_alloc_skb); + +void skb_add_rx_frag(struct sk_buff *skb, int i, struct page *page, int off, + int size, unsigned int truesize) +{ + skb_fill_page_desc(skb, i, page, off, size); + skb->len += size; + skb->data_len += size; + skb->truesize += truesize; +} +EXPORT_SYMBOL(skb_add_rx_frag); + +void skb_coalesce_rx_frag(struct sk_buff *skb, int i, int size, + unsigned int truesize) +{ + skb_frag_t *frag = &skb_shinfo(skb)->frags[i]; + + skb_frag_size_add(frag, size); + skb->len += size; + skb->data_len += size; + skb->truesize += truesize; +} +EXPORT_SYMBOL(skb_coalesce_rx_frag); + +static void skb_drop_list(struct sk_buff **listp) +{ + kfree_skb_list(*listp); + *listp = NULL; +} + +static inline void skb_drop_fraglist(struct sk_buff *skb) +{ + skb_drop_list(&skb_shinfo(skb)->frag_list); +} + +static void skb_clone_fraglist(struct sk_buff *skb) +{ + struct sk_buff *list; + + skb_walk_frags(skb, list) + skb_get(list); +} + +static void skb_free_head(struct sk_buff *skb) +{ + if (skb->head_frag) + put_page(virt_to_head_page(skb->head)); + else + kfree(skb->head); +} + +static void skb_release_data(struct sk_buff *skb) +{ + struct skb_shared_info *shinfo = skb_shinfo(skb); + int i; + + if (skb->cloned && + atomic_sub_return(skb->nohdr ? (1 << SKB_DATAREF_SHIFT) + 1 : 1, + &shinfo->dataref)) + return; + + for (i = 0; i < shinfo->nr_frags; i++) + __skb_frag_unref(&shinfo->frags[i]); + + /* + * If skb buf is from userspace, we need to notify the caller + * the lower device DMA has done; + */ + if (shinfo->tx_flags & SKBTX_DEV_ZEROCOPY) { + struct ubuf_info *uarg; + + uarg = shinfo->destructor_arg; + if (uarg->callback) + uarg->callback(uarg, true); + } + + if (shinfo->frag_list) + kfree_skb_list(shinfo->frag_list); + + skb_free_head(skb); +} + +/* + * Free an skbuff by memory without cleaning the state. + */ +static void kfree_skbmem(struct sk_buff *skb) +{ + struct sk_buff_fclones *fclones; + + switch (skb->fclone) { + case SKB_FCLONE_UNAVAILABLE: + kmem_cache_free(skbuff_head_cache, skb); + break; + + case SKB_FCLONE_ORIG: + fclones = container_of(skb, struct sk_buff_fclones, skb1); + if (atomic_dec_and_test(&fclones->fclone_ref)) + kmem_cache_free(skbuff_fclone_cache, fclones); + break; + + case SKB_FCLONE_CLONE: + fclones = container_of(skb, struct sk_buff_fclones, skb2); + + /* The clone portion is available for + * fast-cloning again. + */ + skb->fclone = SKB_FCLONE_FREE; + + if (atomic_dec_and_test(&fclones->fclone_ref)) + kmem_cache_free(skbuff_fclone_cache, fclones); + break; + } +} + +static void skb_release_head_state(struct sk_buff *skb) +{ + skb_dst_drop(skb); +#ifdef CONFIG_XFRM + secpath_put(skb->sp); +#endif + if (skb->destructor) { + WARN_ON(in_irq()); + skb->destructor(skb); + } +#if IS_ENABLED(CONFIG_NF_CONNTRACK) + nf_conntrack_put(skb->nfct); +#endif +#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER) + nf_bridge_put(skb->nf_bridge); +#endif +/* XXX: IS this still necessary? - JHS */ +#ifdef CONFIG_NET_SCHED + skb->tc_index = 0; +#ifdef CONFIG_NET_CLS_ACT + skb->tc_verd = 0; +#endif +#endif +} + +/* Free everything but the sk_buff shell. */ +static void skb_release_all(struct sk_buff *skb) +{ + skb_release_head_state(skb); + if (likely(skb->head)) + skb_release_data(skb); +} + +/** + * __kfree_skb - private function + * @skb: buffer + * + * Free an sk_buff. Release anything attached to the buffer. + * Clean the state. This is an internal helper function. Users should + * always call kfree_skb + */ + +void __kfree_skb(struct sk_buff *skb) +{ + skb_release_all(skb); + kfree_skbmem(skb); +} +EXPORT_SYMBOL(__kfree_skb); + +/** + * kfree_skb - free an sk_buff + * @skb: buffer to free + * + * Drop a reference to the buffer and free it if the usage count has + * hit zero. + */ +void kfree_skb(struct sk_buff *skb) +{ + if (unlikely(!skb)) + return; + if (likely(atomic_read(&skb->users) == 1)) + smp_rmb(); + else if (likely(!atomic_dec_and_test(&skb->users))) + return; + trace_kfree_skb(skb, __builtin_return_address(0)); + __kfree_skb(skb); +} +EXPORT_SYMBOL(kfree_skb); + +void kfree_skb_list(struct sk_buff *segs) +{ + while (segs) { + struct sk_buff *next = segs->next; + + kfree_skb(segs); + segs = next; + } +} +EXPORT_SYMBOL(kfree_skb_list); + +/** + * skb_tx_error - report an sk_buff xmit error + * @skb: buffer that triggered an error + * + * Report xmit error if a device callback is tracking this skb. + * skb must be freed afterwards. + */ +void skb_tx_error(struct sk_buff *skb) +{ + if (skb_shinfo(skb)->tx_flags & SKBTX_DEV_ZEROCOPY) { + struct ubuf_info *uarg; + + uarg = skb_shinfo(skb)->destructor_arg; + if (uarg->callback) + uarg->callback(uarg, false); + skb_shinfo(skb)->tx_flags &= ~SKBTX_DEV_ZEROCOPY; + } +} +EXPORT_SYMBOL(skb_tx_error); + +/** + * consume_skb - free an skbuff + * @skb: buffer to free + * + * Drop a ref to the buffer and free it if the usage count has hit zero + * Functions identically to kfree_skb, but kfree_skb assumes that the frame + * is being dropped after a failure and notes that + */ +void consume_skb(struct sk_buff *skb) +{ + if (unlikely(!skb)) + return; + if (likely(atomic_read(&skb->users) == 1)) + smp_rmb(); + else if (likely(!atomic_dec_and_test(&skb->users))) + return; + trace_consume_skb(skb); + __kfree_skb(skb); +} +EXPORT_SYMBOL(consume_skb); + +/* Make sure a field is enclosed inside headers_start/headers_end section */ +#define CHECK_SKB_FIELD(field) \ + BUILD_BUG_ON(offsetof(struct sk_buff, field) < \ + offsetof(struct sk_buff, headers_start)); \ + BUILD_BUG_ON(offsetof(struct sk_buff, field) > \ + offsetof(struct sk_buff, headers_end)); \ + +static void __copy_skb_header(struct sk_buff *new, const struct sk_buff *old) +{ + new->tstamp = old->tstamp; + /* We do not copy old->sk */ + new->dev = old->dev; + memcpy(new->cb, old->cb, sizeof(old->cb)); + skb_dst_copy(new, old); +#ifdef CONFIG_XFRM + new->sp = secpath_get(old->sp); +#endif + __nf_copy(new, old, false); + + /* Note : this field could be in headers_start/headers_end section + * It is not yet because we do not want to have a 16 bit hole + */ + new->queue_mapping = old->queue_mapping; + + memcpy(&new->headers_start, &old->headers_start, + offsetof(struct sk_buff, headers_end) - + offsetof(struct sk_buff, headers_start)); + CHECK_SKB_FIELD(protocol); + CHECK_SKB_FIELD(csum); + CHECK_SKB_FIELD(hash); + CHECK_SKB_FIELD(priority); + CHECK_SKB_FIELD(skb_iif); + CHECK_SKB_FIELD(vlan_proto); + CHECK_SKB_FIELD(vlan_tci); + CHECK_SKB_FIELD(transport_header); + CHECK_SKB_FIELD(network_header); + CHECK_SKB_FIELD(mac_header); + CHECK_SKB_FIELD(inner_protocol); + CHECK_SKB_FIELD(inner_transport_header); + CHECK_SKB_FIELD(inner_network_header); + CHECK_SKB_FIELD(inner_mac_header); + CHECK_SKB_FIELD(mark); +#ifdef CONFIG_NETWORK_SECMARK + CHECK_SKB_FIELD(secmark); +#endif +#ifdef CONFIG_NET_RX_BUSY_POLL + CHECK_SKB_FIELD(napi_id); +#endif +#ifdef CONFIG_NET_SCHED + CHECK_SKB_FIELD(tc_index); +#ifdef CONFIG_NET_CLS_ACT + CHECK_SKB_FIELD(tc_verd); +#endif +#endif + +} + +/* + * You should not add any new code to this function. Add it to + * __copy_skb_header above instead. + */ +static struct sk_buff *__skb_clone(struct sk_buff *n, struct sk_buff *skb) +{ +#define C(x) n->x = skb->x + + n->next = n->prev = NULL; + n->sk = NULL; + __copy_skb_header(n, skb); + + C(len); + C(data_len); + C(mac_len); + n->hdr_len = skb->nohdr ? skb_headroom(skb) : skb->hdr_len; + n->cloned = 1; + n->nohdr = 0; + n->destructor = NULL; + C(tail); + C(end); + C(head); + C(head_frag); + C(data); + C(truesize); + atomic_set(&n->users, 1); + + atomic_inc(&(skb_shinfo(skb)->dataref)); + skb->cloned = 1; + + return n; +#undef C +} + +/** + * skb_morph - morph one skb into another + * @dst: the skb to receive the contents + * @src: the skb to supply the contents + * + * This is identical to skb_clone except that the target skb is + * supplied by the user. + * + * The target skb is returned upon exit. + */ +struct sk_buff *skb_morph(struct sk_buff *dst, struct sk_buff *src) +{ + skb_release_all(dst); + return __skb_clone(dst, src); +} +EXPORT_SYMBOL_GPL(skb_morph); + +/** + * skb_copy_ubufs - copy userspace skb frags buffers to kernel + * @skb: the skb to modify + * @gfp_mask: allocation priority + * + * This must be called on SKBTX_DEV_ZEROCOPY skb. + * It will copy all frags into kernel and drop the reference + * to userspace pages. + * + * If this function is called from an interrupt gfp_mask() must be + * %GFP_ATOMIC. + * + * Returns 0 on success or a negative error code on failure + * to allocate kernel memory to copy to. + */ +int skb_copy_ubufs(struct sk_buff *skb, gfp_t gfp_mask) +{ + int i; + int num_frags = skb_shinfo(skb)->nr_frags; + struct page *page, *head = NULL; + struct ubuf_info *uarg = skb_shinfo(skb)->destructor_arg; + + for (i = 0; i < num_frags; i++) { + u8 *vaddr; + skb_frag_t *f = &skb_shinfo(skb)->frags[i]; + + page = alloc_page(gfp_mask); + if (!page) { + while (head) { + struct page *next = (struct page *)page_private(head); + put_page(head); + head = next; + } + return -ENOMEM; + } + vaddr = kmap_atomic(skb_frag_page(f)); + memcpy(page_address(page), + vaddr + f->page_offset, skb_frag_size(f)); + kunmap_atomic(vaddr); + set_page_private(page, (unsigned long)head); + head = page; + } + + /* skb frags release userspace buffers */ + for (i = 0; i < num_frags; i++) + skb_frag_unref(skb, i); + + uarg->callback(uarg, false); + + /* skb frags point to kernel buffers */ + for (i = num_frags - 1; i >= 0; i--) { + __skb_fill_page_desc(skb, i, head, 0, + skb_shinfo(skb)->frags[i].size); + head = (struct page *)page_private(head); + } + + skb_shinfo(skb)->tx_flags &= ~SKBTX_DEV_ZEROCOPY; + return 0; +} +EXPORT_SYMBOL_GPL(skb_copy_ubufs); + +/** + * skb_clone - duplicate an sk_buff + * @skb: buffer to clone + * @gfp_mask: allocation priority + * + * Duplicate an &sk_buff. The new one is not owned by a socket. Both + * copies share the same packet data but not structure. The new + * buffer has a reference count of 1. If the allocation fails the + * function returns %NULL otherwise the new buffer is returned. + * + * If this function is called from an interrupt gfp_mask() must be + * %GFP_ATOMIC. + */ + +struct sk_buff *skb_clone(struct sk_buff *skb, gfp_t gfp_mask) +{ + struct sk_buff_fclones *fclones = container_of(skb, + struct sk_buff_fclones, + skb1); + struct sk_buff *n = &fclones->skb2; + + if (skb_orphan_frags(skb, gfp_mask)) + return NULL; + + if (skb->fclone == SKB_FCLONE_ORIG && + n->fclone == SKB_FCLONE_FREE) { + n->fclone = SKB_FCLONE_CLONE; + atomic_inc(&fclones->fclone_ref); + } else { + if (skb_pfmemalloc(skb)) + gfp_mask |= __GFP_MEMALLOC; + + n = kmem_cache_alloc(skbuff_head_cache, gfp_mask); + if (!n) + return NULL; + + kmemcheck_annotate_bitfield(n, flags1); + n->fclone = SKB_FCLONE_UNAVAILABLE; + } + + return __skb_clone(n, skb); +} +EXPORT_SYMBOL(skb_clone); + +static void skb_headers_offset_update(struct sk_buff *skb, int off) +{ + /* Only adjust this if it actually is csum_start rather than csum */ + if (skb->ip_summed == CHECKSUM_PARTIAL) + skb->csum_start += off; + /* {transport,network,mac}_header and tail are relative to skb->head */ + skb->transport_header += off; + skb->network_header += off; + if (skb_mac_header_was_set(skb)) + skb->mac_header += off; + skb->inner_transport_header += off; + skb->inner_network_header += off; + skb->inner_mac_header += off; +} + +static void copy_skb_header(struct sk_buff *new, const struct sk_buff *old) +{ + __copy_skb_header(new, old); + + skb_shinfo(new)->gso_size = skb_shinfo(old)->gso_size; + skb_shinfo(new)->gso_segs = skb_shinfo(old)->gso_segs; + skb_shinfo(new)->gso_type = skb_shinfo(old)->gso_type; +} + +static inline int skb_alloc_rx_flag(const struct sk_buff *skb) +{ + if (skb_pfmemalloc(skb)) + return SKB_ALLOC_RX; + return 0; +} + +/** + * skb_copy - create private copy of an sk_buff + * @skb: buffer to copy + * @gfp_mask: allocation priority + * + * Make a copy of both an &sk_buff and its data. This is used when the + * caller wishes to modify the data and needs a private copy of the + * data to alter. Returns %NULL on failure or the pointer to the buffer + * on success. The returned buffer has a reference count of 1. + * + * As by-product this function converts non-linear &sk_buff to linear + * one, so that &sk_buff becomes completely private and caller is allowed + * to modify all the data of returned buffer. This means that this + * function is not recommended for use in circumstances when only + * header is going to be modified. Use pskb_copy() instead. + */ + +struct sk_buff *skb_copy(const struct sk_buff *skb, gfp_t gfp_mask) +{ + int headerlen = skb_headroom(skb); + unsigned int size = skb_end_offset(skb) + skb->data_len; + struct sk_buff *n = __alloc_skb(size, gfp_mask, + skb_alloc_rx_flag(skb), NUMA_NO_NODE); + + if (!n) + return NULL; + + /* Set the data pointer */ + skb_reserve(n, headerlen); + /* Set the tail pointer and length */ + skb_put(n, skb->len); + + if (skb_copy_bits(skb, -headerlen, n->head, headerlen + skb->len)) + BUG(); + + copy_skb_header(n, skb); + return n; +} +EXPORT_SYMBOL(skb_copy); + +/** + * __pskb_copy_fclone - create copy of an sk_buff with private head. + * @skb: buffer to copy + * @headroom: headroom of new skb + * @gfp_mask: allocation priority + * @fclone: if true allocate the copy of the skb from the fclone + * cache instead of the head cache; it is recommended to set this + * to true for the cases where the copy will likely be cloned + * + * Make a copy of both an &sk_buff and part of its data, located + * in header. Fragmented data remain shared. This is used when + * the caller wishes to modify only header of &sk_buff and needs + * private copy of the header to alter. Returns %NULL on failure + * or the pointer to the buffer on success. + * The returned buffer has a reference count of 1. + */ + +struct sk_buff *__pskb_copy_fclone(struct sk_buff *skb, int headroom, + gfp_t gfp_mask, bool fclone) +{ + unsigned int size = skb_headlen(skb) + headroom; + int flags = skb_alloc_rx_flag(skb) | (fclone ? SKB_ALLOC_FCLONE : 0); + struct sk_buff *n = __alloc_skb(size, gfp_mask, flags, NUMA_NO_NODE); + + if (!n) + goto out; + + /* Set the data pointer */ + skb_reserve(n, headroom); + /* Set the tail pointer and length */ + skb_put(n, skb_headlen(skb)); + /* Copy the bytes */ + skb_copy_from_linear_data(skb, n->data, n->len); + + n->truesize += skb->data_len; + n->data_len = skb->data_len; + n->len = skb->len; + + if (skb_shinfo(skb)->nr_frags) { + int i; + + if (skb_orphan_frags(skb, gfp_mask)) { + kfree_skb(n); + n = NULL; + goto out; + } + for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { + skb_shinfo(n)->frags[i] = skb_shinfo(skb)->frags[i]; + skb_frag_ref(skb, i); + } + skb_shinfo(n)->nr_frags = i; + } + + if (skb_has_frag_list(skb)) { + skb_shinfo(n)->frag_list = skb_shinfo(skb)->frag_list; + skb_clone_fraglist(n); + } + + copy_skb_header(n, skb); +out: + return n; +} +EXPORT_SYMBOL(__pskb_copy_fclone); + +/** + * pskb_expand_head - reallocate header of &sk_buff + * @skb: buffer to reallocate + * @nhead: room to add at head + * @ntail: room to add at tail + * @gfp_mask: allocation priority + * + * Expands (or creates identical copy, if @nhead and @ntail are zero) + * header of @skb. &sk_buff itself is not changed. &sk_buff MUST have + * reference count of 1. Returns zero in the case of success or error, + * if expansion failed. In the last case, &sk_buff is not changed. + * + * All the pointers pointing into skb header may change and must be + * reloaded after call to this function. + */ + +int pskb_expand_head(struct sk_buff *skb, int nhead, int ntail, + gfp_t gfp_mask) +{ + int i; + u8 *data; + int size = nhead + skb_end_offset(skb) + ntail; + long off; + + BUG_ON(nhead < 0); + + if (skb_shared(skb)) + BUG(); + + size = SKB_DATA_ALIGN(size); + + if (skb_pfmemalloc(skb)) + gfp_mask |= __GFP_MEMALLOC; + data = kmalloc_reserve(size + SKB_DATA_ALIGN(sizeof(struct skb_shared_info)), + gfp_mask, NUMA_NO_NODE, NULL); + if (!data) + goto nodata; + size = SKB_WITH_OVERHEAD(ksize(data)); + + /* Copy only real data... and, alas, header. This should be + * optimized for the cases when header is void. + */ + memcpy(data + nhead, skb->head, skb_tail_pointer(skb) - skb->head); + + memcpy((struct skb_shared_info *)(data + size), + skb_shinfo(skb), + offsetof(struct skb_shared_info, frags[skb_shinfo(skb)->nr_frags])); + + /* + * if shinfo is shared we must drop the old head gracefully, but if it + * is not we can just drop the old head and let the existing refcount + * be since all we did is relocate the values + */ + if (skb_cloned(skb)) { + /* copy this zero copy skb frags */ + if (skb_orphan_frags(skb, gfp_mask)) + goto nofrags; + for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) + skb_frag_ref(skb, i); + + if (skb_has_frag_list(skb)) + skb_clone_fraglist(skb); + + skb_release_data(skb); + } else { + skb_free_head(skb); + } + off = (data + nhead) - skb->head; + + skb->head = data; + skb->head_frag = 0; + skb->data += off; +#ifdef NET_SKBUFF_DATA_USES_OFFSET + skb->end = size; + off = nhead; +#else + skb->end = skb->head + size; +#endif + skb->tail += off; + skb_headers_offset_update(skb, nhead); + skb->cloned = 0; + skb->hdr_len = 0; + skb->nohdr = 0; + atomic_set(&skb_shinfo(skb)->dataref, 1); + return 0; + +nofrags: + kfree(data); +nodata: + return -ENOMEM; +} +EXPORT_SYMBOL(pskb_expand_head); + +/* Make private copy of skb with writable head and some headroom */ + +struct sk_buff *skb_realloc_headroom(struct sk_buff *skb, unsigned int headroom) +{ + struct sk_buff *skb2; + int delta = headroom - skb_headroom(skb); + + if (delta <= 0) + skb2 = pskb_copy(skb, GFP_ATOMIC); + else { + skb2 = skb_clone(skb, GFP_ATOMIC); + if (skb2 && pskb_expand_head(skb2, SKB_DATA_ALIGN(delta), 0, + GFP_ATOMIC)) { + kfree_skb(skb2); + skb2 = NULL; + } + } + return skb2; +} +EXPORT_SYMBOL(skb_realloc_headroom); + +/** + * skb_copy_expand - copy and expand sk_buff + * @skb: buffer to copy + * @newheadroom: new free bytes at head + * @newtailroom: new free bytes at tail + * @gfp_mask: allocation priority + * + * Make a copy of both an &sk_buff and its data and while doing so + * allocate additional space. + * + * This is used when the caller wishes to modify the data and needs a + * private copy of the data to alter as well as more space for new fields. + * Returns %NULL on failure or the pointer to the buffer + * on success. The returned buffer has a reference count of 1. + * + * You must pass %GFP_ATOMIC as the allocation priority if this function + * is called from an interrupt. + */ +struct sk_buff *skb_copy_expand(const struct sk_buff *skb, + int newheadroom, int newtailroom, + gfp_t gfp_mask) +{ + /* + * Allocate the copy buffer + */ + struct sk_buff *n = __alloc_skb(newheadroom + skb->len + newtailroom, + gfp_mask, skb_alloc_rx_flag(skb), + NUMA_NO_NODE); + int oldheadroom = skb_headroom(skb); + int head_copy_len, head_copy_off; + + if (!n) + return NULL; + + skb_reserve(n, newheadroom); + + /* Set the tail pointer and length */ + skb_put(n, skb->len); + + head_copy_len = oldheadroom; + head_copy_off = 0; + if (newheadroom <= head_copy_len) + head_copy_len = newheadroom; + else + head_copy_off = newheadroom - head_copy_len; + + /* Copy the linear header and data. */ + if (skb_copy_bits(skb, -head_copy_len, n->head + head_copy_off, + skb->len + head_copy_len)) + BUG(); + + copy_skb_header(n, skb); + + skb_headers_offset_update(n, newheadroom - oldheadroom); + + return n; +} +EXPORT_SYMBOL(skb_copy_expand); + +/** + * skb_pad - zero pad the tail of an skb + * @skb: buffer to pad + * @pad: space to pad + * + * Ensure that a buffer is followed by a padding area that is zero + * filled. Used by network drivers which may DMA or transfer data + * beyond the buffer end onto the wire. + * + * May return error in out of memory cases. The skb is freed on error. + */ + +int skb_pad(struct sk_buff *skb, int pad) +{ + int err; + int ntail; + + /* If the skbuff is non linear tailroom is always zero.. */ + if (!skb_cloned(skb) && skb_tailroom(skb) >= pad) { + memset(skb->data+skb->len, 0, pad); + return 0; + } + + ntail = skb->data_len + pad - (skb->end - skb->tail); + if (likely(skb_cloned(skb) || ntail > 0)) { + err = pskb_expand_head(skb, 0, ntail, GFP_ATOMIC); + if (unlikely(err)) + goto free_skb; + } + + /* FIXME: The use of this function with non-linear skb's really needs + * to be audited. + */ + err = skb_linearize(skb); + if (unlikely(err)) + goto free_skb; + + memset(skb->data + skb->len, 0, pad); + return 0; + +free_skb: + kfree_skb(skb); + return err; +} +EXPORT_SYMBOL(skb_pad); + +/** + * pskb_put - add data to the tail of a potentially fragmented buffer + * @skb: start of the buffer to use + * @tail: tail fragment of the buffer to use + * @len: amount of data to add + * + * This function extends the used data area of the potentially + * fragmented buffer. @tail must be the last fragment of @skb -- or + * @skb itself. If this would exceed the total buffer size the kernel + * will panic. A pointer to the first byte of the extra data is + * returned. + */ + +unsigned char *pskb_put(struct sk_buff *skb, struct sk_buff *tail, int len) +{ + if (tail != skb) { + skb->data_len += len; + skb->len += len; + } + return skb_put(tail, len); +} +EXPORT_SYMBOL_GPL(pskb_put); + +/** + * skb_put - add data to a buffer + * @skb: buffer to use + * @len: amount of data to add + * + * This function extends the used data area of the buffer. If this would + * exceed the total buffer size the kernel will panic. A pointer to the + * first byte of the extra data is returned. + */ +unsigned char *skb_put(struct sk_buff *skb, unsigned int len) +{ + unsigned char *tmp = skb_tail_pointer(skb); + SKB_LINEAR_ASSERT(skb); + skb->tail += len; + skb->len += len; + if (unlikely(skb->tail > skb->end)) + skb_over_panic(skb, len, __builtin_return_address(0)); + return tmp; +} +EXPORT_SYMBOL(skb_put); + +/** + * skb_push - add data to the start of a buffer + * @skb: buffer to use + * @len: amount of data to add + * + * This function extends the used data area of the buffer at the buffer + * start. If this would exceed the total buffer headroom the kernel will + * panic. A pointer to the first byte of the extra data is returned. + */ +unsigned char *skb_push(struct sk_buff *skb, unsigned int len) +{ + skb->data -= len; + skb->len += len; + if (unlikely(skb->datahead)) + skb_under_panic(skb, len, __builtin_return_address(0)); + return skb->data; +} +EXPORT_SYMBOL(skb_push); + +/** + * skb_pull - remove data from the start of a buffer + * @skb: buffer to use + * @len: amount of data to remove + * + * This function removes data from the start of a buffer, returning + * the memory to the headroom. A pointer to the next data in the buffer + * is returned. Once the data has been pulled future pushes will overwrite + * the old data. + */ +unsigned char *skb_pull(struct sk_buff *skb, unsigned int len) +{ + return skb_pull_inline(skb, len); +} +EXPORT_SYMBOL(skb_pull); + +/** + * skb_trim - remove end from a buffer + * @skb: buffer to alter + * @len: new length + * + * Cut the length of a buffer down by removing data from the tail. If + * the buffer is already under the length specified it is not modified. + * The skb must be linear. + */ +void skb_trim(struct sk_buff *skb, unsigned int len) +{ + if (skb->len > len) + __skb_trim(skb, len); +} +EXPORT_SYMBOL(skb_trim); + +/* Trims skb to length len. It can change skb pointers. + */ + +int ___pskb_trim(struct sk_buff *skb, unsigned int len) +{ + struct sk_buff **fragp; + struct sk_buff *frag; + int offset = skb_headlen(skb); + int nfrags = skb_shinfo(skb)->nr_frags; + int i; + int err; + + if (skb_cloned(skb) && + unlikely((err = pskb_expand_head(skb, 0, 0, GFP_ATOMIC)))) + return err; + + i = 0; + if (offset >= len) + goto drop_pages; + + for (; i < nfrags; i++) { + int end = offset + skb_frag_size(&skb_shinfo(skb)->frags[i]); + + if (end < len) { + offset = end; + continue; + } + + skb_frag_size_set(&skb_shinfo(skb)->frags[i++], len - offset); + +drop_pages: + skb_shinfo(skb)->nr_frags = i; + + for (; i < nfrags; i++) + skb_frag_unref(skb, i); + + if (skb_has_frag_list(skb)) + skb_drop_fraglist(skb); + goto done; + } + + for (fragp = &skb_shinfo(skb)->frag_list; (frag = *fragp); + fragp = &frag->next) { + int end = offset + frag->len; + + if (skb_shared(frag)) { + struct sk_buff *nfrag; + + nfrag = skb_clone(frag, GFP_ATOMIC); + if (unlikely(!nfrag)) + return -ENOMEM; + + nfrag->next = frag->next; + consume_skb(frag); + frag = nfrag; + *fragp = frag; + } + + if (end < len) { + offset = end; + continue; + } + + if (end > len && + unlikely((err = pskb_trim(frag, len - offset)))) + return err; + + if (frag->next) + skb_drop_list(&frag->next); + break; + } + +done: + if (len > skb_headlen(skb)) { + skb->data_len -= skb->len - len; + skb->len = len; + } else { + skb->len = len; + skb->data_len = 0; + skb_set_tail_pointer(skb, len); + } + + return 0; +} +EXPORT_SYMBOL(___pskb_trim); + +/** + * __pskb_pull_tail - advance tail of skb header + * @skb: buffer to reallocate + * @delta: number of bytes to advance tail + * + * The function makes a sense only on a fragmented &sk_buff, + * it expands header moving its tail forward and copying necessary + * data from fragmented part. + * + * &sk_buff MUST have reference count of 1. + * + * Returns %NULL (and &sk_buff does not change) if pull failed + * or value of new tail of skb in the case of success. + * + * All the pointers pointing into skb header may change and must be + * reloaded after call to this function. + */ + +/* Moves tail of skb head forward, copying data from fragmented part, + * when it is necessary. + * 1. It may fail due to malloc failure. + * 2. It may change skb pointers. + * + * It is pretty complicated. Luckily, it is called only in exceptional cases. + */ +unsigned char *__pskb_pull_tail(struct sk_buff *skb, int delta) +{ + /* If skb has not enough free space at tail, get new one + * plus 128 bytes for future expansions. If we have enough + * room at tail, reallocate without expansion only if skb is cloned. + */ + int i, k, eat = (skb->tail + delta) - skb->end; + + if (eat > 0 || skb_cloned(skb)) { + if (pskb_expand_head(skb, 0, eat > 0 ? eat + 128 : 0, + GFP_ATOMIC)) + return NULL; + } + + if (skb_copy_bits(skb, skb_headlen(skb), skb_tail_pointer(skb), delta)) + BUG(); + + /* Optimization: no fragments, no reasons to preestimate + * size of pulled pages. Superb. + */ + if (!skb_has_frag_list(skb)) + goto pull_pages; + + /* Estimate size of pulled pages. */ + eat = delta; + for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { + int size = skb_frag_size(&skb_shinfo(skb)->frags[i]); + + if (size >= eat) + goto pull_pages; + eat -= size; + } + + /* If we need update frag list, we are in troubles. + * Certainly, it possible to add an offset to skb data, + * but taking into account that pulling is expected to + * be very rare operation, it is worth to fight against + * further bloating skb head and crucify ourselves here instead. + * Pure masohism, indeed. 8)8) + */ + if (eat) { + struct sk_buff *list = skb_shinfo(skb)->frag_list; + struct sk_buff *clone = NULL; + struct sk_buff *insp = NULL; + + do { + BUG_ON(!list); + + if (list->len <= eat) { + /* Eaten as whole. */ + eat -= list->len; + list = list->next; + insp = list; + } else { + /* Eaten partially. */ + + if (skb_shared(list)) { + /* Sucks! We need to fork list. :-( */ + clone = skb_clone(list, GFP_ATOMIC); + if (!clone) + return NULL; + insp = list->next; + list = clone; + } else { + /* This may be pulled without + * problems. */ + insp = list; + } + if (!pskb_pull(list, eat)) { + kfree_skb(clone); + return NULL; + } + break; + } + } while (eat); + + /* Free pulled out fragments. */ + while ((list = skb_shinfo(skb)->frag_list) != insp) { + skb_shinfo(skb)->frag_list = list->next; + kfree_skb(list); + } + /* And insert new clone at head. */ + if (clone) { + clone->next = list; + skb_shinfo(skb)->frag_list = clone; + } + } + /* Success! Now we may commit changes to skb data. */ + +pull_pages: + eat = delta; + k = 0; + for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { + int size = skb_frag_size(&skb_shinfo(skb)->frags[i]); + + if (size <= eat) { + skb_frag_unref(skb, i); + eat -= size; + } else { + skb_shinfo(skb)->frags[k] = skb_shinfo(skb)->frags[i]; + if (eat) { + skb_shinfo(skb)->frags[k].page_offset += eat; + skb_frag_size_sub(&skb_shinfo(skb)->frags[k], eat); + eat = 0; + } + k++; + } + } + skb_shinfo(skb)->nr_frags = k; + + skb->tail += delta; + skb->data_len -= delta; + + return skb_tail_pointer(skb); +} +EXPORT_SYMBOL(__pskb_pull_tail); + +/** + * skb_copy_bits - copy bits from skb to kernel buffer + * @skb: source skb + * @offset: offset in source + * @to: destination buffer + * @len: number of bytes to copy + * + * Copy the specified number of bytes from the source skb to the + * destination buffer. + * + * CAUTION ! : + * If its prototype is ever changed, + * check arch/{*}/net/{*}.S files, + * since it is called from BPF assembly code. + */ +int skb_copy_bits(const struct sk_buff *skb, int offset, void *to, int len) +{ + int start = skb_headlen(skb); + struct sk_buff *frag_iter; + int i, copy; + + if (offset > (int)skb->len - len) + goto fault; + + /* Copy header. */ + if ((copy = start - offset) > 0) { + if (copy > len) + copy = len; + skb_copy_from_linear_data_offset(skb, offset, to, copy); + if ((len -= copy) == 0) + return 0; + offset += copy; + to += copy; + } + + for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { + int end; + skb_frag_t *f = &skb_shinfo(skb)->frags[i]; + + WARN_ON(start > offset + len); + + end = start + skb_frag_size(f); + if ((copy = end - offset) > 0) { + u8 *vaddr; + + if (copy > len) + copy = len; + + vaddr = kmap_atomic(skb_frag_page(f)); + memcpy(to, + vaddr + f->page_offset + offset - start, + copy); + kunmap_atomic(vaddr); + + if ((len -= copy) == 0) + return 0; + offset += copy; + to += copy; + } + start = end; + } + + skb_walk_frags(skb, frag_iter) { + int end; + + WARN_ON(start > offset + len); + + end = start + frag_iter->len; + if ((copy = end - offset) > 0) { + if (copy > len) + copy = len; + if (skb_copy_bits(frag_iter, offset - start, to, copy)) + goto fault; + if ((len -= copy) == 0) + return 0; + offset += copy; + to += copy; + } + start = end; + } + + if (!len) + return 0; + +fault: + return -EFAULT; +} +EXPORT_SYMBOL(skb_copy_bits); + +/* + * Callback from splice_to_pipe(), if we need to release some pages + * at the end of the spd in case we error'ed out in filling the pipe. + */ +static void sock_spd_release(struct splice_pipe_desc *spd, unsigned int i) +{ + put_page(spd->pages[i]); +} + +static struct page *linear_to_page(struct page *page, unsigned int *len, + unsigned int *offset, + struct sock *sk) +{ + struct page_frag *pfrag = sk_page_frag(sk); + + if (!sk_page_frag_refill(sk, pfrag)) + return NULL; + + *len = min_t(unsigned int, *len, pfrag->size - pfrag->offset); + + memcpy(page_address(pfrag->page) + pfrag->offset, + page_address(page) + *offset, *len); + *offset = pfrag->offset; + pfrag->offset += *len; + + return pfrag->page; +} + +static bool spd_can_coalesce(const struct splice_pipe_desc *spd, + struct page *page, + unsigned int offset) +{ + return spd->nr_pages && + spd->pages[spd->nr_pages - 1] == page && + (spd->partial[spd->nr_pages - 1].offset + + spd->partial[spd->nr_pages - 1].len == offset); +} + +/* + * Fill page/offset/length into spd, if it can hold more pages. + */ +static bool spd_fill_page(struct splice_pipe_desc *spd, + struct pipe_inode_info *pipe, struct page *page, + unsigned int *len, unsigned int offset, + bool linear, + struct sock *sk) +{ + if (unlikely(spd->nr_pages == MAX_SKB_FRAGS)) + return true; + + if (linear) { + page = linear_to_page(page, len, &offset, sk); + if (!page) + return true; + } + if (spd_can_coalesce(spd, page, offset)) { + spd->partial[spd->nr_pages - 1].len += *len; + return false; + } + get_page(page); + spd->pages[spd->nr_pages] = page; + spd->partial[spd->nr_pages].len = *len; + spd->partial[spd->nr_pages].offset = offset; + spd->nr_pages++; + + return false; +} + +static bool __splice_segment(struct page *page, unsigned int poff, + unsigned int plen, unsigned int *off, + unsigned int *len, + struct splice_pipe_desc *spd, bool linear, + struct sock *sk, + struct pipe_inode_info *pipe) +{ + if (!*len) + return true; + + /* skip this segment if already processed */ + if (*off >= plen) { + *off -= plen; + return false; + } + + /* ignore any bits we already processed */ + poff += *off; + plen -= *off; + *off = 0; + + do { + unsigned int flen = min(*len, plen); + + if (spd_fill_page(spd, pipe, page, &flen, poff, + linear, sk)) + return true; + poff += flen; + plen -= flen; + *len -= flen; + } while (*len && plen); + + return false; +} + +/* + * Map linear and fragment data from the skb to spd. It reports true if the + * pipe is full or if we already spliced the requested length. + */ +static bool __skb_splice_bits(struct sk_buff *skb, struct pipe_inode_info *pipe, + unsigned int *offset, unsigned int *len, + struct splice_pipe_desc *spd, struct sock *sk) +{ + int seg; + + /* map the linear part : + * If skb->head_frag is set, this 'linear' part is backed by a + * fragment, and if the head is not shared with any clones then + * we can avoid a copy since we own the head portion of this page. + */ + if (__splice_segment(virt_to_page(skb->data), + (unsigned long) skb->data & (PAGE_SIZE - 1), + skb_headlen(skb), + offset, len, spd, + skb_head_is_locked(skb), + sk, pipe)) + return true; + + /* + * then map the fragments + */ + for (seg = 0; seg < skb_shinfo(skb)->nr_frags; seg++) { + const skb_frag_t *f = &skb_shinfo(skb)->frags[seg]; + + if (__splice_segment(skb_frag_page(f), + f->page_offset, skb_frag_size(f), + offset, len, spd, false, sk, pipe)) + return true; + } + + return false; +} + +/* + * Map data from the skb to a pipe. Should handle both the linear part, + * the fragments, and the frag list. It does NOT handle frag lists within + * the frag list, if such a thing exists. We'd probably need to recurse to + * handle that cleanly. + */ +int skb_splice_bits(struct sk_buff *skb, unsigned int offset, + struct pipe_inode_info *pipe, unsigned int tlen, + unsigned int flags) +{ + struct partial_page partial[MAX_SKB_FRAGS]; + struct page *pages[MAX_SKB_FRAGS]; + struct splice_pipe_desc spd = { + .pages = pages, + .partial = partial, + .nr_pages_max = MAX_SKB_FRAGS, + .flags = flags, + .ops = &nosteal_pipe_buf_ops, + .spd_release = sock_spd_release, + }; + struct sk_buff *frag_iter; + struct sock *sk = skb->sk; + int ret = 0; + + /* + * __skb_splice_bits() only fails if the output has no room left, + * so no point in going over the frag_list for the error case. + */ + if (__skb_splice_bits(skb, pipe, &offset, &tlen, &spd, sk)) + goto done; + else if (!tlen) + goto done; + + /* + * now see if we have a frag_list to map + */ + skb_walk_frags(skb, frag_iter) { + if (!tlen) + break; + if (__skb_splice_bits(frag_iter, pipe, &offset, &tlen, &spd, sk)) + break; + } + +done: + if (spd.nr_pages) { + /* + * Drop the socket lock, otherwise we have reverse + * locking dependencies between sk_lock and i_mutex + * here as compared to sendfile(). We enter here + * with the socket lock held, and splice_to_pipe() will + * grab the pipe inode lock. For sendfile() emulation, + * we call into ->sendpage() with the i_mutex lock held + * and networking will grab the socket lock. + */ + release_sock(sk); + ret = splice_to_pipe(pipe, &spd); + lock_sock(sk); + } + + return ret; +} + +/** + * skb_store_bits - store bits from kernel buffer to skb + * @skb: destination buffer + * @offset: offset in destination + * @from: source buffer + * @len: number of bytes to copy + * + * Copy the specified number of bytes from the source buffer to the + * destination skb. This function handles all the messy bits of + * traversing fragment lists and such. + */ + +int skb_store_bits(struct sk_buff *skb, int offset, const void *from, int len) +{ + int start = skb_headlen(skb); + struct sk_buff *frag_iter; + int i, copy; + + if (offset > (int)skb->len - len) + goto fault; + + if ((copy = start - offset) > 0) { + if (copy > len) + copy = len; + skb_copy_to_linear_data_offset(skb, offset, from, copy); + if ((len -= copy) == 0) + return 0; + offset += copy; + from += copy; + } + + for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { + skb_frag_t *frag = &skb_shinfo(skb)->frags[i]; + int end; + + WARN_ON(start > offset + len); + + end = start + skb_frag_size(frag); + if ((copy = end - offset) > 0) { + u8 *vaddr; + + if (copy > len) + copy = len; + + vaddr = kmap_atomic(skb_frag_page(frag)); + memcpy(vaddr + frag->page_offset + offset - start, + from, copy); + kunmap_atomic(vaddr); + + if ((len -= copy) == 0) + return 0; + offset += copy; + from += copy; + } + start = end; + } + + skb_walk_frags(skb, frag_iter) { + int end; + + WARN_ON(start > offset + len); + + end = start + frag_iter->len; + if ((copy = end - offset) > 0) { + if (copy > len) + copy = len; + if (skb_store_bits(frag_iter, offset - start, + from, copy)) + goto fault; + if ((len -= copy) == 0) + return 0; + offset += copy; + from += copy; + } + start = end; + } + if (!len) + return 0; + +fault: + return -EFAULT; +} +EXPORT_SYMBOL(skb_store_bits); + +/* Checksum skb data. */ +__wsum __skb_checksum(const struct sk_buff *skb, int offset, int len, + __wsum csum, const struct skb_checksum_ops *ops) +{ + int start = skb_headlen(skb); + int i, copy = start - offset; + struct sk_buff *frag_iter; + int pos = 0; + + /* Checksum header. */ + if (copy > 0) { + if (copy > len) + copy = len; + csum = ops->update(skb->data + offset, copy, csum); + if ((len -= copy) == 0) + return csum; + offset += copy; + pos = copy; + } + + for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { + int end; + skb_frag_t *frag = &skb_shinfo(skb)->frags[i]; + + WARN_ON(start > offset + len); + + end = start + skb_frag_size(frag); + if ((copy = end - offset) > 0) { + __wsum csum2; + u8 *vaddr; + + if (copy > len) + copy = len; + vaddr = kmap_atomic(skb_frag_page(frag)); + csum2 = ops->update(vaddr + frag->page_offset + + offset - start, copy, 0); + kunmap_atomic(vaddr); + csum = ops->combine(csum, csum2, pos, copy); + if (!(len -= copy)) + return csum; + offset += copy; + pos += copy; + } + start = end; + } + + skb_walk_frags(skb, frag_iter) { + int end; + + WARN_ON(start > offset + len); + + end = start + frag_iter->len; + if ((copy = end - offset) > 0) { + __wsum csum2; + if (copy > len) + copy = len; + csum2 = __skb_checksum(frag_iter, offset - start, + copy, 0, ops); + csum = ops->combine(csum, csum2, pos, copy); + if ((len -= copy) == 0) + return csum; + offset += copy; + pos += copy; + } + start = end; + } + BUG_ON(len); + + return csum; +} +EXPORT_SYMBOL(__skb_checksum); + +__wsum skb_checksum(const struct sk_buff *skb, int offset, + int len, __wsum csum) +{ + const struct skb_checksum_ops ops = { + .update = csum_partial_ext, + .combine = csum_block_add_ext, + }; + + return __skb_checksum(skb, offset, len, csum, &ops); +} +EXPORT_SYMBOL(skb_checksum); + +/* Both of above in one bottle. */ + +__wsum skb_copy_and_csum_bits(const struct sk_buff *skb, int offset, + u8 *to, int len, __wsum csum) +{ + int start = skb_headlen(skb); + int i, copy = start - offset; + struct sk_buff *frag_iter; + int pos = 0; + + /* Copy header. */ + if (copy > 0) { + if (copy > len) + copy = len; + csum = csum_partial_copy_nocheck(skb->data + offset, to, + copy, csum); + if ((len -= copy) == 0) + return csum; + offset += copy; + to += copy; + pos = copy; + } + + for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { + int end; + + WARN_ON(start > offset + len); + + end = start + skb_frag_size(&skb_shinfo(skb)->frags[i]); + if ((copy = end - offset) > 0) { + __wsum csum2; + u8 *vaddr; + skb_frag_t *frag = &skb_shinfo(skb)->frags[i]; + + if (copy > len) + copy = len; + vaddr = kmap_atomic(skb_frag_page(frag)); + csum2 = csum_partial_copy_nocheck(vaddr + + frag->page_offset + + offset - start, to, + copy, 0); + kunmap_atomic(vaddr); + csum = csum_block_add(csum, csum2, pos); + if (!(len -= copy)) + return csum; + offset += copy; + to += copy; + pos += copy; + } + start = end; + } + + skb_walk_frags(skb, frag_iter) { + __wsum csum2; + int end; + + WARN_ON(start > offset + len); + + end = start + frag_iter->len; + if ((copy = end - offset) > 0) { + if (copy > len) + copy = len; + csum2 = skb_copy_and_csum_bits(frag_iter, + offset - start, + to, copy, 0); + csum = csum_block_add(csum, csum2, pos); + if ((len -= copy) == 0) + return csum; + offset += copy; + to += copy; + pos += copy; + } + start = end; + } + BUG_ON(len); + return csum; +} +EXPORT_SYMBOL(skb_copy_and_csum_bits); + + /** + * skb_zerocopy_headlen - Calculate headroom needed for skb_zerocopy() + * @from: source buffer + * + * Calculates the amount of linear headroom needed in the 'to' skb passed + * into skb_zerocopy(). + */ +unsigned int +skb_zerocopy_headlen(const struct sk_buff *from) +{ + unsigned int hlen = 0; + + if (!from->head_frag || + skb_headlen(from) < L1_CACHE_BYTES || + skb_shinfo(from)->nr_frags >= MAX_SKB_FRAGS) + hlen = skb_headlen(from); + + if (skb_has_frag_list(from)) + hlen = from->len; + + return hlen; +} +EXPORT_SYMBOL_GPL(skb_zerocopy_headlen); + +/** + * skb_zerocopy - Zero copy skb to skb + * @to: destination buffer + * @from: source buffer + * @len: number of bytes to copy from source buffer + * @hlen: size of linear headroom in destination buffer + * + * Copies up to `len` bytes from `from` to `to` by creating references + * to the frags in the source buffer. + * + * The `hlen` as calculated by skb_zerocopy_headlen() specifies the + * headroom in the `to` buffer. + * + * Return value: + * 0: everything is OK + * -ENOMEM: couldn't orphan frags of @from due to lack of memory + * -EFAULT: skb_copy_bits() found some problem with skb geometry + */ +int +skb_zerocopy(struct sk_buff *to, struct sk_buff *from, int len, int hlen) +{ + int i, j = 0; + int plen = 0; /* length of skb->head fragment */ + int ret; + struct page *page; + unsigned int offset; + + BUG_ON(!from->head_frag && !hlen); + + /* dont bother with small payloads */ + if (len <= skb_tailroom(to)) + return skb_copy_bits(from, 0, skb_put(to, len), len); + + if (hlen) { + ret = skb_copy_bits(from, 0, skb_put(to, hlen), hlen); + if (unlikely(ret)) + return ret; + len -= hlen; + } else { + plen = min_t(int, skb_headlen(from), len); + if (plen) { + page = virt_to_head_page(from->head); + offset = from->data - (unsigned char *)page_address(page); + __skb_fill_page_desc(to, 0, page, offset, plen); + get_page(page); + j = 1; + len -= plen; + } + } + + to->truesize += len + plen; + to->len += len + plen; + to->data_len += len + plen; + + if (unlikely(skb_orphan_frags(from, GFP_ATOMIC))) { + skb_tx_error(from); + return -ENOMEM; + } + + for (i = 0; i < skb_shinfo(from)->nr_frags; i++) { + if (!len) + break; + skb_shinfo(to)->frags[j] = skb_shinfo(from)->frags[i]; + skb_shinfo(to)->frags[j].size = min_t(int, skb_shinfo(to)->frags[j].size, len); + len -= skb_shinfo(to)->frags[j].size; + skb_frag_ref(to, j); + j++; + } + skb_shinfo(to)->nr_frags = j; + + return 0; +} +EXPORT_SYMBOL_GPL(skb_zerocopy); + +void skb_copy_and_csum_dev(const struct sk_buff *skb, u8 *to) +{ + __wsum csum; + long csstart; + + if (skb->ip_summed == CHECKSUM_PARTIAL) + csstart = skb_checksum_start_offset(skb); + else + csstart = skb_headlen(skb); + + BUG_ON(csstart > skb_headlen(skb)); + + skb_copy_from_linear_data(skb, to, csstart); + + csum = 0; + if (csstart != skb->len) + csum = skb_copy_and_csum_bits(skb, csstart, to + csstart, + skb->len - csstart, 0); + + if (skb->ip_summed == CHECKSUM_PARTIAL) { + long csstuff = csstart + skb->csum_offset; + + *((__sum16 *)(to + csstuff)) = csum_fold(csum); + } +} +EXPORT_SYMBOL(skb_copy_and_csum_dev); + +/** + * skb_dequeue - remove from the head of the queue + * @list: list to dequeue from + * + * Remove the head of the list. The list lock is taken so the function + * may be used safely with other locking list functions. The head item is + * returned or %NULL if the list is empty. + */ + +struct sk_buff *skb_dequeue(struct sk_buff_head *list) +{ + unsigned long flags; + struct sk_buff *result; + + spin_lock_irqsave(&list->lock, flags); + result = __skb_dequeue(list); + spin_unlock_irqrestore(&list->lock, flags); + return result; +} +EXPORT_SYMBOL(skb_dequeue); + +/** + * skb_dequeue_tail - remove from the tail of the queue + * @list: list to dequeue from + * + * Remove the tail of the list. The list lock is taken so the function + * may be used safely with other locking list functions. The tail item is + * returned or %NULL if the list is empty. + */ +struct sk_buff *skb_dequeue_tail(struct sk_buff_head *list) +{ + unsigned long flags; + struct sk_buff *result; + + spin_lock_irqsave(&list->lock, flags); + result = __skb_dequeue_tail(list); + spin_unlock_irqrestore(&list->lock, flags); + return result; +} +EXPORT_SYMBOL(skb_dequeue_tail); + +/** + * skb_queue_purge - empty a list + * @list: list to empty + * + * Delete all buffers on an &sk_buff list. Each buffer is removed from + * the list and one reference dropped. This function takes the list + * lock and is atomic with respect to other list locking functions. + */ +void skb_queue_purge(struct sk_buff_head *list) +{ + struct sk_buff *skb; + while ((skb = skb_dequeue(list)) != NULL) + kfree_skb(skb); +} +EXPORT_SYMBOL(skb_queue_purge); + +/** + * skb_queue_head - queue a buffer at the list head + * @list: list to use + * @newsk: buffer to queue + * + * Queue a buffer at the start of the list. This function takes the + * list lock and can be used safely with other locking &sk_buff functions + * safely. + * + * A buffer cannot be placed on two lists at the same time. + */ +void skb_queue_head(struct sk_buff_head *list, struct sk_buff *newsk) +{ + unsigned long flags; + + spin_lock_irqsave(&list->lock, flags); + __skb_queue_head(list, newsk); + spin_unlock_irqrestore(&list->lock, flags); +} +EXPORT_SYMBOL(skb_queue_head); + +/** + * skb_queue_tail - queue a buffer at the list tail + * @list: list to use + * @newsk: buffer to queue + * + * Queue a buffer at the tail of the list. This function takes the + * list lock and can be used safely with other locking &sk_buff functions + * safely. + * + * A buffer cannot be placed on two lists at the same time. + */ +void skb_queue_tail(struct sk_buff_head *list, struct sk_buff *newsk) +{ + unsigned long flags; + + spin_lock_irqsave(&list->lock, flags); + __skb_queue_tail(list, newsk); + spin_unlock_irqrestore(&list->lock, flags); +} +EXPORT_SYMBOL(skb_queue_tail); + +/** + * skb_unlink - remove a buffer from a list + * @skb: buffer to remove + * @list: list to use + * + * Remove a packet from a list. The list locks are taken and this + * function is atomic with respect to other list locked calls + * + * You must know what list the SKB is on. + */ +void skb_unlink(struct sk_buff *skb, struct sk_buff_head *list) +{ + unsigned long flags; + + spin_lock_irqsave(&list->lock, flags); + __skb_unlink(skb, list); + spin_unlock_irqrestore(&list->lock, flags); +} +EXPORT_SYMBOL(skb_unlink); + +/** + * skb_append - append a buffer + * @old: buffer to insert after + * @newsk: buffer to insert + * @list: list to use + * + * Place a packet after a given packet in a list. The list locks are taken + * and this function is atomic with respect to other list locked calls. + * A buffer cannot be placed on two lists at the same time. + */ +void skb_append(struct sk_buff *old, struct sk_buff *newsk, struct sk_buff_head *list) +{ + unsigned long flags; + + spin_lock_irqsave(&list->lock, flags); + __skb_queue_after(list, old, newsk); + spin_unlock_irqrestore(&list->lock, flags); +} +EXPORT_SYMBOL(skb_append); + +/** + * skb_insert - insert a buffer + * @old: buffer to insert before + * @newsk: buffer to insert + * @list: list to use + * + * Place a packet before a given packet in a list. The list locks are + * taken and this function is atomic with respect to other list locked + * calls. + * + * A buffer cannot be placed on two lists at the same time. + */ +void skb_insert(struct sk_buff *old, struct sk_buff *newsk, struct sk_buff_head *list) +{ + unsigned long flags; + + spin_lock_irqsave(&list->lock, flags); + __skb_insert(newsk, old->prev, old, list); + spin_unlock_irqrestore(&list->lock, flags); +} +EXPORT_SYMBOL(skb_insert); + +static inline void skb_split_inside_header(struct sk_buff *skb, + struct sk_buff* skb1, + const u32 len, const int pos) +{ + int i; + + skb_copy_from_linear_data_offset(skb, len, skb_put(skb1, pos - len), + pos - len); + /* And move data appendix as is. */ + for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) + skb_shinfo(skb1)->frags[i] = skb_shinfo(skb)->frags[i]; + + skb_shinfo(skb1)->nr_frags = skb_shinfo(skb)->nr_frags; + skb_shinfo(skb)->nr_frags = 0; + skb1->data_len = skb->data_len; + skb1->len += skb1->data_len; + skb->data_len = 0; + skb->len = len; + skb_set_tail_pointer(skb, len); +} + +static inline void skb_split_no_header(struct sk_buff *skb, + struct sk_buff* skb1, + const u32 len, int pos) +{ + int i, k = 0; + const int nfrags = skb_shinfo(skb)->nr_frags; + + skb_shinfo(skb)->nr_frags = 0; + skb1->len = skb1->data_len = skb->len - len; + skb->len = len; + skb->data_len = len - pos; + + for (i = 0; i < nfrags; i++) { + int size = skb_frag_size(&skb_shinfo(skb)->frags[i]); + + if (pos + size > len) { + skb_shinfo(skb1)->frags[k] = skb_shinfo(skb)->frags[i]; + + if (pos < len) { + /* Split frag. + * We have two variants in this case: + * 1. Move all the frag to the second + * part, if it is possible. F.e. + * this approach is mandatory for TUX, + * where splitting is expensive. + * 2. Split is accurately. We make this. + */ + skb_frag_ref(skb, i); + skb_shinfo(skb1)->frags[0].page_offset += len - pos; + skb_frag_size_sub(&skb_shinfo(skb1)->frags[0], len - pos); + skb_frag_size_set(&skb_shinfo(skb)->frags[i], len - pos); + skb_shinfo(skb)->nr_frags++; + } + k++; + } else + skb_shinfo(skb)->nr_frags++; + pos += size; + } + skb_shinfo(skb1)->nr_frags = k; +} + +/** + * skb_split - Split fragmented skb to two parts at length len. + * @skb: the buffer to split + * @skb1: the buffer to receive the second part + * @len: new length for skb + */ +void skb_split(struct sk_buff *skb, struct sk_buff *skb1, const u32 len) +{ + int pos = skb_headlen(skb); + + skb_shinfo(skb1)->tx_flags = skb_shinfo(skb)->tx_flags & SKBTX_SHARED_FRAG; + if (len < pos) /* Split line is inside header. */ + skb_split_inside_header(skb, skb1, len, pos); + else /* Second chunk has no header, nothing to copy. */ + skb_split_no_header(skb, skb1, len, pos); +} +EXPORT_SYMBOL(skb_split); + +/* Shifting from/to a cloned skb is a no-go. + * + * Caller cannot keep skb_shinfo related pointers past calling here! + */ +static int skb_prepare_for_shift(struct sk_buff *skb) +{ + return skb_cloned(skb) && pskb_expand_head(skb, 0, 0, GFP_ATOMIC); +} + +/** + * skb_shift - Shifts paged data partially from skb to another + * @tgt: buffer into which tail data gets added + * @skb: buffer from which the paged data comes from + * @shiftlen: shift up to this many bytes + * + * Attempts to shift up to shiftlen worth of bytes, which may be less than + * the length of the skb, from skb to tgt. Returns number bytes shifted. + * It's up to caller to free skb if everything was shifted. + * + * If @tgt runs out of frags, the whole operation is aborted. + * + * Skb cannot include anything else but paged data while tgt is allowed + * to have non-paged data as well. + * + * TODO: full sized shift could be optimized but that would need + * specialized skb free'er to handle frags without up-to-date nr_frags. + */ +int skb_shift(struct sk_buff *tgt, struct sk_buff *skb, int shiftlen) +{ + int from, to, merge, todo; + struct skb_frag_struct *fragfrom, *fragto; + + BUG_ON(shiftlen > skb->len); + BUG_ON(skb_headlen(skb)); /* Would corrupt stream */ + + todo = shiftlen; + from = 0; + to = skb_shinfo(tgt)->nr_frags; + fragfrom = &skb_shinfo(skb)->frags[from]; + + /* Actual merge is delayed until the point when we know we can + * commit all, so that we don't have to undo partial changes + */ + if (!to || + !skb_can_coalesce(tgt, to, skb_frag_page(fragfrom), + fragfrom->page_offset)) { + merge = -1; + } else { + merge = to - 1; + + todo -= skb_frag_size(fragfrom); + if (todo < 0) { + if (skb_prepare_for_shift(skb) || + skb_prepare_for_shift(tgt)) + return 0; + + /* All previous frag pointers might be stale! */ + fragfrom = &skb_shinfo(skb)->frags[from]; + fragto = &skb_shinfo(tgt)->frags[merge]; + + skb_frag_size_add(fragto, shiftlen); + skb_frag_size_sub(fragfrom, shiftlen); + fragfrom->page_offset += shiftlen; + + goto onlymerged; + } + + from++; + } + + /* Skip full, not-fitting skb to avoid expensive operations */ + if ((shiftlen == skb->len) && + (skb_shinfo(skb)->nr_frags - from) > (MAX_SKB_FRAGS - to)) + return 0; + + if (skb_prepare_for_shift(skb) || skb_prepare_for_shift(tgt)) + return 0; + + while ((todo > 0) && (from < skb_shinfo(skb)->nr_frags)) { + if (to == MAX_SKB_FRAGS) + return 0; + + fragfrom = &skb_shinfo(skb)->frags[from]; + fragto = &skb_shinfo(tgt)->frags[to]; + + if (todo >= skb_frag_size(fragfrom)) { + *fragto = *fragfrom; + todo -= skb_frag_size(fragfrom); + from++; + to++; + + } else { + __skb_frag_ref(fragfrom); + fragto->page = fragfrom->page; + fragto->page_offset = fragfrom->page_offset; + skb_frag_size_set(fragto, todo); + + fragfrom->page_offset += todo; + skb_frag_size_sub(fragfrom, todo); + todo = 0; + + to++; + break; + } + } + + /* Ready to "commit" this state change to tgt */ + skb_shinfo(tgt)->nr_frags = to; + + if (merge >= 0) { + fragfrom = &skb_shinfo(skb)->frags[0]; + fragto = &skb_shinfo(tgt)->frags[merge]; + + skb_frag_size_add(fragto, skb_frag_size(fragfrom)); + __skb_frag_unref(fragfrom); + } + + /* Reposition in the original skb */ + to = 0; + while (from < skb_shinfo(skb)->nr_frags) + skb_shinfo(skb)->frags[to++] = skb_shinfo(skb)->frags[from++]; + skb_shinfo(skb)->nr_frags = to; + + BUG_ON(todo > 0 && !skb_shinfo(skb)->nr_frags); + +onlymerged: + /* Most likely the tgt won't ever need its checksum anymore, skb on + * the other hand might need it if it needs to be resent + */ + tgt->ip_summed = CHECKSUM_PARTIAL; + skb->ip_summed = CHECKSUM_PARTIAL; + + /* Yak, is it really working this way? Some helper please? */ + skb->len -= shiftlen; + skb->data_len -= shiftlen; + skb->truesize -= shiftlen; + tgt->len += shiftlen; + tgt->data_len += shiftlen; + tgt->truesize += shiftlen; + + return shiftlen; +} + +/** + * skb_prepare_seq_read - Prepare a sequential read of skb data + * @skb: the buffer to read + * @from: lower offset of data to be read + * @to: upper offset of data to be read + * @st: state variable + * + * Initializes the specified state variable. Must be called before + * invoking skb_seq_read() for the first time. + */ +void skb_prepare_seq_read(struct sk_buff *skb, unsigned int from, + unsigned int to, struct skb_seq_state *st) +{ + st->lower_offset = from; + st->upper_offset = to; + st->root_skb = st->cur_skb = skb; + st->frag_idx = st->stepped_offset = 0; + st->frag_data = NULL; +} +EXPORT_SYMBOL(skb_prepare_seq_read); + +/** + * skb_seq_read - Sequentially read skb data + * @consumed: number of bytes consumed by the caller so far + * @data: destination pointer for data to be returned + * @st: state variable + * + * Reads a block of skb data at @consumed relative to the + * lower offset specified to skb_prepare_seq_read(). Assigns + * the head of the data block to @data and returns the length + * of the block or 0 if the end of the skb data or the upper + * offset has been reached. + * + * The caller is not required to consume all of the data + * returned, i.e. @consumed is typically set to the number + * of bytes already consumed and the next call to + * skb_seq_read() will return the remaining part of the block. + * + * Note 1: The size of each block of data returned can be arbitrary, + * this limitation is the cost for zerocopy sequential + * reads of potentially non linear data. + * + * Note 2: Fragment lists within fragments are not implemented + * at the moment, state->root_skb could be replaced with + * a stack for this purpose. + */ +unsigned int skb_seq_read(unsigned int consumed, const u8 **data, + struct skb_seq_state *st) +{ + unsigned int block_limit, abs_offset = consumed + st->lower_offset; + skb_frag_t *frag; + + if (unlikely(abs_offset >= st->upper_offset)) { + if (st->frag_data) { + kunmap_atomic(st->frag_data); + st->frag_data = NULL; + } + return 0; + } + +next_skb: + block_limit = skb_headlen(st->cur_skb) + st->stepped_offset; + + if (abs_offset < block_limit && !st->frag_data) { + *data = st->cur_skb->data + (abs_offset - st->stepped_offset); + return block_limit - abs_offset; + } + + if (st->frag_idx == 0 && !st->frag_data) + st->stepped_offset += skb_headlen(st->cur_skb); + + while (st->frag_idx < skb_shinfo(st->cur_skb)->nr_frags) { + frag = &skb_shinfo(st->cur_skb)->frags[st->frag_idx]; + block_limit = skb_frag_size(frag) + st->stepped_offset; + + if (abs_offset < block_limit) { + if (!st->frag_data) + st->frag_data = kmap_atomic(skb_frag_page(frag)); + + *data = (u8 *) st->frag_data + frag->page_offset + + (abs_offset - st->stepped_offset); + + return block_limit - abs_offset; + } + + if (st->frag_data) { + kunmap_atomic(st->frag_data); + st->frag_data = NULL; + } + + st->frag_idx++; + st->stepped_offset += skb_frag_size(frag); + } + + if (st->frag_data) { + kunmap_atomic(st->frag_data); + st->frag_data = NULL; + } + + if (st->root_skb == st->cur_skb && skb_has_frag_list(st->root_skb)) { + st->cur_skb = skb_shinfo(st->root_skb)->frag_list; + st->frag_idx = 0; + goto next_skb; + } else if (st->cur_skb->next) { + st->cur_skb = st->cur_skb->next; + st->frag_idx = 0; + goto next_skb; + } + + return 0; +} +EXPORT_SYMBOL(skb_seq_read); + +/** + * skb_abort_seq_read - Abort a sequential read of skb data + * @st: state variable + * + * Must be called if skb_seq_read() was not called until it + * returned 0. + */ +void skb_abort_seq_read(struct skb_seq_state *st) +{ + if (st->frag_data) + kunmap_atomic(st->frag_data); +} +EXPORT_SYMBOL(skb_abort_seq_read); + +#define TS_SKB_CB(state) ((struct skb_seq_state *) &((state)->cb)) + +static unsigned int skb_ts_get_next_block(unsigned int offset, const u8 **text, + struct ts_config *conf, + struct ts_state *state) +{ + return skb_seq_read(offset, text, TS_SKB_CB(state)); +} + +static void skb_ts_finish(struct ts_config *conf, struct ts_state *state) +{ + skb_abort_seq_read(TS_SKB_CB(state)); +} + +/** + * skb_find_text - Find a text pattern in skb data + * @skb: the buffer to look in + * @from: search offset + * @to: search limit + * @config: textsearch configuration + * @state: uninitialized textsearch state variable + * + * Finds a pattern in the skb data according to the specified + * textsearch configuration. Use textsearch_next() to retrieve + * subsequent occurrences of the pattern. Returns the offset + * to the first occurrence or UINT_MAX if no match was found. + */ +unsigned int skb_find_text(struct sk_buff *skb, unsigned int from, + unsigned int to, struct ts_config *config, + struct ts_state *state) +{ + unsigned int ret; + + config->get_next_block = skb_ts_get_next_block; + config->finish = skb_ts_finish; + + skb_prepare_seq_read(skb, from, to, TS_SKB_CB(state)); + + ret = textsearch_find(config, state); + return (ret <= to - from ? ret : UINT_MAX); +} +EXPORT_SYMBOL(skb_find_text); + +/** + * skb_append_datato_frags - append the user data to a skb + * @sk: sock structure + * @skb: skb structure to be appended with user data. + * @getfrag: call back function to be used for getting the user data + * @from: pointer to user message iov + * @length: length of the iov message + * + * Description: This procedure append the user data in the fragment part + * of the skb if any page alloc fails user this procedure returns -ENOMEM + */ +int skb_append_datato_frags(struct sock *sk, struct sk_buff *skb, + int (*getfrag)(void *from, char *to, int offset, + int len, int odd, struct sk_buff *skb), + void *from, int length) +{ + int frg_cnt = skb_shinfo(skb)->nr_frags; + int copy; + int offset = 0; + int ret; + struct page_frag *pfrag = ¤t->task_frag; + + do { + /* Return error if we don't have space for new frag */ + if (frg_cnt >= MAX_SKB_FRAGS) + return -EMSGSIZE; + + if (!sk_page_frag_refill(sk, pfrag)) + return -ENOMEM; + + /* copy the user data to page */ + copy = min_t(int, length, pfrag->size - pfrag->offset); + + ret = getfrag(from, page_address(pfrag->page) + pfrag->offset, + offset, copy, 0, skb); + if (ret < 0) + return -EFAULT; + + /* copy was successful so update the size parameters */ + skb_fill_page_desc(skb, frg_cnt, pfrag->page, pfrag->offset, + copy); + frg_cnt++; + pfrag->offset += copy; + get_page(pfrag->page); + + skb->truesize += copy; + atomic_add(copy, &sk->sk_wmem_alloc); + skb->len += copy; + skb->data_len += copy; + offset += copy; + length -= copy; + + } while (length > 0); + + return 0; +} +EXPORT_SYMBOL(skb_append_datato_frags); + +/** + * skb_pull_rcsum - pull skb and update receive checksum + * @skb: buffer to update + * @len: length of data pulled + * + * This function performs an skb_pull on the packet and updates + * the CHECKSUM_COMPLETE checksum. It should be used on + * receive path processing instead of skb_pull unless you know + * that the checksum difference is zero (e.g., a valid IP header) + * or you are setting ip_summed to CHECKSUM_NONE. + */ +unsigned char *skb_pull_rcsum(struct sk_buff *skb, unsigned int len) +{ + BUG_ON(len > skb->len); + skb->len -= len; + BUG_ON(skb->len < skb->data_len); + skb_postpull_rcsum(skb, skb->data, len); + return skb->data += len; +} +EXPORT_SYMBOL_GPL(skb_pull_rcsum); + +/** + * skb_segment - Perform protocol segmentation on skb. + * @head_skb: buffer to segment + * @features: features for the output path (see dev->features) + * + * This function performs segmentation on the given skb. It returns + * a pointer to the first in a list of new skbs for the segments. + * In case of error it returns ERR_PTR(err). + */ +struct sk_buff *skb_segment(struct sk_buff *head_skb, + netdev_features_t features) +{ + struct sk_buff *segs = NULL; + struct sk_buff *tail = NULL; + struct sk_buff *list_skb = skb_shinfo(head_skb)->frag_list; + skb_frag_t *frag = skb_shinfo(head_skb)->frags; + unsigned int mss = skb_shinfo(head_skb)->gso_size; + unsigned int doffset = head_skb->data - skb_mac_header(head_skb); + struct sk_buff *frag_skb = head_skb; + unsigned int offset = doffset; + unsigned int tnl_hlen = skb_tnl_header_len(head_skb); + unsigned int headroom; + unsigned int len; + __be16 proto; + bool csum; + int sg = !!(features & NETIF_F_SG); + int nfrags = skb_shinfo(head_skb)->nr_frags; + int err = -ENOMEM; + int i = 0; + int pos; + int dummy; + + __skb_push(head_skb, doffset); + proto = skb_network_protocol(head_skb, &dummy); + if (unlikely(!proto)) + return ERR_PTR(-EINVAL); + + csum = !head_skb->encap_hdr_csum && + !!can_checksum_protocol(features, proto); + + headroom = skb_headroom(head_skb); + pos = skb_headlen(head_skb); + + do { + struct sk_buff *nskb; + skb_frag_t *nskb_frag; + int hsize; + int size; + + len = head_skb->len - offset; + if (len > mss) + len = mss; + + hsize = skb_headlen(head_skb) - offset; + if (hsize < 0) + hsize = 0; + if (hsize > len || !sg) + hsize = len; + + if (!hsize && i >= nfrags && skb_headlen(list_skb) && + (skb_headlen(list_skb) == len || sg)) { + BUG_ON(skb_headlen(list_skb) > len); + + i = 0; + nfrags = skb_shinfo(list_skb)->nr_frags; + frag = skb_shinfo(list_skb)->frags; + frag_skb = list_skb; + pos += skb_headlen(list_skb); + + while (pos < offset + len) { + BUG_ON(i >= nfrags); + + size = skb_frag_size(frag); + if (pos + size > offset + len) + break; + + i++; + pos += size; + frag++; + } + + nskb = skb_clone(list_skb, GFP_ATOMIC); + list_skb = list_skb->next; + + if (unlikely(!nskb)) + goto err; + + if (unlikely(pskb_trim(nskb, len))) { + kfree_skb(nskb); + goto err; + } + + hsize = skb_end_offset(nskb); + if (skb_cow_head(nskb, doffset + headroom)) { + kfree_skb(nskb); + goto err; + } + + nskb->truesize += skb_end_offset(nskb) - hsize; + skb_release_head_state(nskb); + __skb_push(nskb, doffset); + } else { + nskb = __alloc_skb(hsize + doffset + headroom, + GFP_ATOMIC, skb_alloc_rx_flag(head_skb), + NUMA_NO_NODE); + + if (unlikely(!nskb)) + goto err; + + skb_reserve(nskb, headroom); + __skb_put(nskb, doffset); + } + + if (segs) + tail->next = nskb; + else + segs = nskb; + tail = nskb; + + __copy_skb_header(nskb, head_skb); + + skb_headers_offset_update(nskb, skb_headroom(nskb) - headroom); + skb_reset_mac_len(nskb); + + skb_copy_from_linear_data_offset(head_skb, -tnl_hlen, + nskb->data - tnl_hlen, + doffset + tnl_hlen); + + if (nskb->len == len + doffset) + goto perform_csum_check; + + if (!sg) { + nskb->ip_summed = CHECKSUM_NONE; + nskb->csum = skb_copy_and_csum_bits(head_skb, offset, + skb_put(nskb, len), + len, 0); + SKB_GSO_CB(nskb)->csum_start = + skb_headroom(nskb) + doffset; + continue; + } + + nskb_frag = skb_shinfo(nskb)->frags; + + skb_copy_from_linear_data_offset(head_skb, offset, + skb_put(nskb, hsize), hsize); + + skb_shinfo(nskb)->tx_flags = skb_shinfo(head_skb)->tx_flags & + SKBTX_SHARED_FRAG; + + while (pos < offset + len) { + if (i >= nfrags) { + BUG_ON(skb_headlen(list_skb)); + + i = 0; + nfrags = skb_shinfo(list_skb)->nr_frags; + frag = skb_shinfo(list_skb)->frags; + frag_skb = list_skb; + + BUG_ON(!nfrags); + + list_skb = list_skb->next; + } + + if (unlikely(skb_shinfo(nskb)->nr_frags >= + MAX_SKB_FRAGS)) { + net_warn_ratelimited( + "skb_segment: too many frags: %u %u\n", + pos, mss); + goto err; + } + + if (unlikely(skb_orphan_frags(frag_skb, GFP_ATOMIC))) + goto err; + + *nskb_frag = *frag; + __skb_frag_ref(nskb_frag); + size = skb_frag_size(nskb_frag); + + if (pos < offset) { + nskb_frag->page_offset += offset - pos; + skb_frag_size_sub(nskb_frag, offset - pos); + } + + skb_shinfo(nskb)->nr_frags++; + + if (pos + size <= offset + len) { + i++; + frag++; + pos += size; + } else { + skb_frag_size_sub(nskb_frag, pos + size - (offset + len)); + goto skip_fraglist; + } + + nskb_frag++; + } + +skip_fraglist: + nskb->data_len = len - hsize; + nskb->len += nskb->data_len; + nskb->truesize += nskb->data_len; + +perform_csum_check: + if (!csum) { + nskb->csum = skb_checksum(nskb, doffset, + nskb->len - doffset, 0); + nskb->ip_summed = CHECKSUM_NONE; + SKB_GSO_CB(nskb)->csum_start = + skb_headroom(nskb) + doffset; + } + } while ((offset += len) < head_skb->len); + + /* Some callers want to get the end of the list. + * Put it in segs->prev to avoid walking the list. + * (see validate_xmit_skb_list() for example) + */ + segs->prev = tail; + return segs; + +err: + kfree_skb_list(segs); + return ERR_PTR(err); +} +EXPORT_SYMBOL_GPL(skb_segment); + +int skb_gro_receive(struct sk_buff **head, struct sk_buff *skb) +{ + struct skb_shared_info *pinfo, *skbinfo = skb_shinfo(skb); + unsigned int offset = skb_gro_offset(skb); + unsigned int headlen = skb_headlen(skb); + struct sk_buff *nskb, *lp, *p = *head; + unsigned int len = skb_gro_len(skb); + unsigned int delta_truesize; + unsigned int headroom; + + if (unlikely(p->len + len >= 65536)) + return -E2BIG; + + lp = NAPI_GRO_CB(p)->last; + pinfo = skb_shinfo(lp); + + if (headlen <= offset) { + skb_frag_t *frag; + skb_frag_t *frag2; + int i = skbinfo->nr_frags; + int nr_frags = pinfo->nr_frags + i; + + if (nr_frags > MAX_SKB_FRAGS) + goto merge; + + offset -= headlen; + pinfo->nr_frags = nr_frags; + skbinfo->nr_frags = 0; + + frag = pinfo->frags + nr_frags; + frag2 = skbinfo->frags + i; + do { + *--frag = *--frag2; + } while (--i); + + frag->page_offset += offset; + skb_frag_size_sub(frag, offset); + + /* all fragments truesize : remove (head size + sk_buff) */ + delta_truesize = skb->truesize - + SKB_TRUESIZE(skb_end_offset(skb)); + + skb->truesize -= skb->data_len; + skb->len -= skb->data_len; + skb->data_len = 0; + + NAPI_GRO_CB(skb)->free = NAPI_GRO_FREE; + goto done; + } else if (skb->head_frag) { + int nr_frags = pinfo->nr_frags; + skb_frag_t *frag = pinfo->frags + nr_frags; + struct page *page = virt_to_head_page(skb->head); + unsigned int first_size = headlen - offset; + unsigned int first_offset; + + if (nr_frags + 1 + skbinfo->nr_frags > MAX_SKB_FRAGS) + goto merge; + + first_offset = skb->data - + (unsigned char *)page_address(page) + + offset; + + pinfo->nr_frags = nr_frags + 1 + skbinfo->nr_frags; + + frag->page.p = page; + frag->page_offset = first_offset; + skb_frag_size_set(frag, first_size); + + memcpy(frag + 1, skbinfo->frags, sizeof(*frag) * skbinfo->nr_frags); + /* We dont need to clear skbinfo->nr_frags here */ + + delta_truesize = skb->truesize - SKB_DATA_ALIGN(sizeof(struct sk_buff)); + NAPI_GRO_CB(skb)->free = NAPI_GRO_FREE_STOLEN_HEAD; + goto done; + } + /* switch back to head shinfo */ + pinfo = skb_shinfo(p); + + if (pinfo->frag_list) + goto merge; + if (skb_gro_len(p) != pinfo->gso_size) + return -E2BIG; + + headroom = skb_headroom(p); + nskb = alloc_skb(headroom + skb_gro_offset(p), GFP_ATOMIC); + if (unlikely(!nskb)) + return -ENOMEM; + + __copy_skb_header(nskb, p); + nskb->mac_len = p->mac_len; + + skb_reserve(nskb, headroom); + __skb_put(nskb, skb_gro_offset(p)); + + skb_set_mac_header(nskb, skb_mac_header(p) - p->data); + skb_set_network_header(nskb, skb_network_offset(p)); + skb_set_transport_header(nskb, skb_transport_offset(p)); + + __skb_pull(p, skb_gro_offset(p)); + memcpy(skb_mac_header(nskb), skb_mac_header(p), + p->data - skb_mac_header(p)); + + skb_shinfo(nskb)->frag_list = p; + skb_shinfo(nskb)->gso_size = pinfo->gso_size; + pinfo->gso_size = 0; + __skb_header_release(p); + NAPI_GRO_CB(nskb)->last = p; + + nskb->data_len += p->len; + nskb->truesize += p->truesize; + nskb->len += p->len; + + *head = nskb; + nskb->next = p->next; + p->next = NULL; + + p = nskb; + +merge: + delta_truesize = skb->truesize; + if (offset > headlen) { + unsigned int eat = offset - headlen; + + skbinfo->frags[0].page_offset += eat; + skb_frag_size_sub(&skbinfo->frags[0], eat); + skb->data_len -= eat; + skb->len -= eat; + offset = headlen; + } + + __skb_pull(skb, offset); + + if (NAPI_GRO_CB(p)->last == p) + skb_shinfo(p)->frag_list = skb; + else + NAPI_GRO_CB(p)->last->next = skb; + NAPI_GRO_CB(p)->last = skb; + __skb_header_release(skb); + lp = p; + +done: + NAPI_GRO_CB(p)->count++; + p->data_len += len; + p->truesize += delta_truesize; + p->len += len; + if (lp != p) { + lp->data_len += len; + lp->truesize += delta_truesize; + lp->len += len; + } + NAPI_GRO_CB(skb)->same_flow = 1; + return 0; +} + +void __init skb_init(void) +{ + skbuff_head_cache = kmem_cache_create("skbuff_head_cache", + sizeof(struct sk_buff), + 0, + SLAB_HWCACHE_ALIGN|SLAB_PANIC, + NULL); + skbuff_fclone_cache = kmem_cache_create("skbuff_fclone_cache", + sizeof(struct sk_buff_fclones), + 0, + SLAB_HWCACHE_ALIGN|SLAB_PANIC, + NULL); +} + +/** + * skb_to_sgvec - Fill a scatter-gather list from a socket buffer + * @skb: Socket buffer containing the buffers to be mapped + * @sg: The scatter-gather list to map into + * @offset: The offset into the buffer's contents to start mapping + * @len: Length of buffer space to be mapped + * + * Fill the specified scatter-gather list with mappings/pointers into a + * region of the buffer space attached to a socket buffer. + */ +static int +__skb_to_sgvec(struct sk_buff *skb, struct scatterlist *sg, int offset, int len) +{ + int start = skb_headlen(skb); + int i, copy = start - offset; + struct sk_buff *frag_iter; + int elt = 0; + + if (copy > 0) { + if (copy > len) + copy = len; + sg_set_buf(sg, skb->data + offset, copy); + elt++; + if ((len -= copy) == 0) + return elt; + offset += copy; + } + + for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { + int end; + + WARN_ON(start > offset + len); + + end = start + skb_frag_size(&skb_shinfo(skb)->frags[i]); + if ((copy = end - offset) > 0) { + skb_frag_t *frag = &skb_shinfo(skb)->frags[i]; + + if (copy > len) + copy = len; + sg_set_page(&sg[elt], skb_frag_page(frag), copy, + frag->page_offset+offset-start); + elt++; + if (!(len -= copy)) + return elt; + offset += copy; + } + start = end; + } + + skb_walk_frags(skb, frag_iter) { + int end; + + WARN_ON(start > offset + len); + + end = start + frag_iter->len; + if ((copy = end - offset) > 0) { + if (copy > len) + copy = len; + elt += __skb_to_sgvec(frag_iter, sg+elt, offset - start, + copy); + if ((len -= copy) == 0) + return elt; + offset += copy; + } + start = end; + } + BUG_ON(len); + return elt; +} + +/* As compared with skb_to_sgvec, skb_to_sgvec_nomark only map skb to given + * sglist without mark the sg which contain last skb data as the end. + * So the caller can mannipulate sg list as will when padding new data after + * the first call without calling sg_unmark_end to expend sg list. + * + * Scenario to use skb_to_sgvec_nomark: + * 1. sg_init_table + * 2. skb_to_sgvec_nomark(payload1) + * 3. skb_to_sgvec_nomark(payload2) + * + * This is equivalent to: + * 1. sg_init_table + * 2. skb_to_sgvec(payload1) + * 3. sg_unmark_end + * 4. skb_to_sgvec(payload2) + * + * When mapping mutilple payload conditionally, skb_to_sgvec_nomark + * is more preferable. + */ +int skb_to_sgvec_nomark(struct sk_buff *skb, struct scatterlist *sg, + int offset, int len) +{ + return __skb_to_sgvec(skb, sg, offset, len); +} +EXPORT_SYMBOL_GPL(skb_to_sgvec_nomark); + +int skb_to_sgvec(struct sk_buff *skb, struct scatterlist *sg, int offset, int len) +{ + int nsg = __skb_to_sgvec(skb, sg, offset, len); + + sg_mark_end(&sg[nsg - 1]); + + return nsg; +} +EXPORT_SYMBOL_GPL(skb_to_sgvec); + +/** + * skb_cow_data - Check that a socket buffer's data buffers are writable + * @skb: The socket buffer to check. + * @tailbits: Amount of trailing space to be added + * @trailer: Returned pointer to the skb where the @tailbits space begins + * + * Make sure that the data buffers attached to a socket buffer are + * writable. If they are not, private copies are made of the data buffers + * and the socket buffer is set to use these instead. + * + * If @tailbits is given, make sure that there is space to write @tailbits + * bytes of data beyond current end of socket buffer. @trailer will be + * set to point to the skb in which this space begins. + * + * The number of scatterlist elements required to completely map the + * COW'd and extended socket buffer will be returned. + */ +int skb_cow_data(struct sk_buff *skb, int tailbits, struct sk_buff **trailer) +{ + int copyflag; + int elt; + struct sk_buff *skb1, **skb_p; + + /* If skb is cloned or its head is paged, reallocate + * head pulling out all the pages (pages are considered not writable + * at the moment even if they are anonymous). + */ + if ((skb_cloned(skb) || skb_shinfo(skb)->nr_frags) && + __pskb_pull_tail(skb, skb_pagelen(skb)-skb_headlen(skb)) == NULL) + return -ENOMEM; + + /* Easy case. Most of packets will go this way. */ + if (!skb_has_frag_list(skb)) { + /* A little of trouble, not enough of space for trailer. + * This should not happen, when stack is tuned to generate + * good frames. OK, on miss we reallocate and reserve even more + * space, 128 bytes is fair. */ + + if (skb_tailroom(skb) < tailbits && + pskb_expand_head(skb, 0, tailbits-skb_tailroom(skb)+128, GFP_ATOMIC)) + return -ENOMEM; + + /* Voila! */ + *trailer = skb; + return 1; + } + + /* Misery. We are in troubles, going to mincer fragments... */ + + elt = 1; + skb_p = &skb_shinfo(skb)->frag_list; + copyflag = 0; + + while ((skb1 = *skb_p) != NULL) { + int ntail = 0; + + /* The fragment is partially pulled by someone, + * this can happen on input. Copy it and everything + * after it. */ + + if (skb_shared(skb1)) + copyflag = 1; + + /* If the skb is the last, worry about trailer. */ + + if (skb1->next == NULL && tailbits) { + if (skb_shinfo(skb1)->nr_frags || + skb_has_frag_list(skb1) || + skb_tailroom(skb1) < tailbits) + ntail = tailbits + 128; + } + + if (copyflag || + skb_cloned(skb1) || + ntail || + skb_shinfo(skb1)->nr_frags || + skb_has_frag_list(skb1)) { + struct sk_buff *skb2; + + /* Fuck, we are miserable poor guys... */ + if (ntail == 0) + skb2 = skb_copy(skb1, GFP_ATOMIC); + else + skb2 = skb_copy_expand(skb1, + skb_headroom(skb1), + ntail, + GFP_ATOMIC); + if (unlikely(skb2 == NULL)) + return -ENOMEM; + + if (skb1->sk) + skb_set_owner_w(skb2, skb1->sk); + + /* Looking around. Are we still alive? + * OK, link new skb, drop old one */ + + skb2->next = skb1->next; + *skb_p = skb2; + kfree_skb(skb1); + skb1 = skb2; + } + elt++; + *trailer = skb1; + skb_p = &skb1->next; + } + + return elt; +} +EXPORT_SYMBOL_GPL(skb_cow_data); + +static void sock_rmem_free(struct sk_buff *skb) +{ + struct sock *sk = skb->sk; + + atomic_sub(skb->truesize, &sk->sk_rmem_alloc); +} + +/* + * Note: We dont mem charge error packets (no sk_forward_alloc changes) + */ +int sock_queue_err_skb(struct sock *sk, struct sk_buff *skb) +{ + if (atomic_read(&sk->sk_rmem_alloc) + skb->truesize >= + (unsigned int)sk->sk_rcvbuf) + return -ENOMEM; + + skb_orphan(skb); + skb->sk = sk; + skb->destructor = sock_rmem_free; + atomic_add(skb->truesize, &sk->sk_rmem_alloc); + + /* before exiting rcu section, make sure dst is refcounted */ + skb_dst_force(skb); + + skb_queue_tail(&sk->sk_error_queue, skb); + if (!sock_flag(sk, SOCK_DEAD)) + sk->sk_data_ready(sk); + return 0; +} +EXPORT_SYMBOL(sock_queue_err_skb); + +struct sk_buff *sock_dequeue_err_skb(struct sock *sk) +{ + struct sk_buff_head *q = &sk->sk_error_queue; + struct sk_buff *skb, *skb_next; + unsigned long flags; + int err = 0; + + spin_lock_irqsave(&q->lock, flags); + skb = __skb_dequeue(q); + if (skb && (skb_next = skb_peek(q))) + err = SKB_EXT_ERR(skb_next)->ee.ee_errno; + spin_unlock_irqrestore(&q->lock, flags); + + sk->sk_err = err; + if (err) + sk->sk_error_report(sk); + + return skb; +} +EXPORT_SYMBOL(sock_dequeue_err_skb); + +/** + * skb_clone_sk - create clone of skb, and take reference to socket + * @skb: the skb to clone + * + * This function creates a clone of a buffer that holds a reference on + * sk_refcnt. Buffers created via this function are meant to be + * returned using sock_queue_err_skb, or free via kfree_skb. + * + * When passing buffers allocated with this function to sock_queue_err_skb + * it is necessary to wrap the call with sock_hold/sock_put in order to + * prevent the socket from being released prior to being enqueued on + * the sk_error_queue. + */ +struct sk_buff *skb_clone_sk(struct sk_buff *skb) +{ + struct sock *sk = skb->sk; + struct sk_buff *clone; + + if (!sk || !atomic_inc_not_zero(&sk->sk_refcnt)) + return NULL; + + clone = skb_clone(skb, GFP_ATOMIC); + if (!clone) { + sock_put(sk); + return NULL; + } + + clone->sk = sk; + clone->destructor = sock_efree; + + return clone; +} +EXPORT_SYMBOL(skb_clone_sk); + +static void __skb_complete_tx_timestamp(struct sk_buff *skb, + struct sock *sk, + int tstype) +{ + struct sock_exterr_skb *serr; + int err; + + serr = SKB_EXT_ERR(skb); + memset(serr, 0, sizeof(*serr)); + serr->ee.ee_errno = ENOMSG; + serr->ee.ee_origin = SO_EE_ORIGIN_TIMESTAMPING; + serr->ee.ee_info = tstype; + if (sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID) { + serr->ee.ee_data = skb_shinfo(skb)->tskey; + if (sk->sk_protocol == IPPROTO_TCP) + serr->ee.ee_data -= sk->sk_tskey; + } + + err = sock_queue_err_skb(sk, skb); + + if (err) + kfree_skb(skb); +} + +void skb_complete_tx_timestamp(struct sk_buff *skb, + struct skb_shared_hwtstamps *hwtstamps) +{ + struct sock *sk = skb->sk; + + /* take a reference to prevent skb_orphan() from freeing the socket */ + sock_hold(sk); + + *skb_hwtstamps(skb) = *hwtstamps; + __skb_complete_tx_timestamp(skb, sk, SCM_TSTAMP_SND); + + sock_put(sk); +} +EXPORT_SYMBOL_GPL(skb_complete_tx_timestamp); + +void __skb_tstamp_tx(struct sk_buff *orig_skb, + struct skb_shared_hwtstamps *hwtstamps, + struct sock *sk, int tstype) +{ + struct sk_buff *skb; + + if (!sk) + return; + + if (hwtstamps) + *skb_hwtstamps(orig_skb) = *hwtstamps; + else + orig_skb->tstamp = ktime_get_real(); + + skb = skb_clone(orig_skb, GFP_ATOMIC); + if (!skb) + return; + + __skb_complete_tx_timestamp(skb, sk, tstype); +} +EXPORT_SYMBOL_GPL(__skb_tstamp_tx); + +void skb_tstamp_tx(struct sk_buff *orig_skb, + struct skb_shared_hwtstamps *hwtstamps) +{ + return __skb_tstamp_tx(orig_skb, hwtstamps, orig_skb->sk, + SCM_TSTAMP_SND); +} +EXPORT_SYMBOL_GPL(skb_tstamp_tx); + +void skb_complete_wifi_ack(struct sk_buff *skb, bool acked) +{ + struct sock *sk = skb->sk; + struct sock_exterr_skb *serr; + int err; + + skb->wifi_acked_valid = 1; + skb->wifi_acked = acked; + + serr = SKB_EXT_ERR(skb); + memset(serr, 0, sizeof(*serr)); + serr->ee.ee_errno = ENOMSG; + serr->ee.ee_origin = SO_EE_ORIGIN_TXSTATUS; + + /* take a reference to prevent skb_orphan() from freeing the socket */ + sock_hold(sk); + + err = sock_queue_err_skb(sk, skb); + if (err) + kfree_skb(skb); + + sock_put(sk); +} +EXPORT_SYMBOL_GPL(skb_complete_wifi_ack); + + +/** + * skb_partial_csum_set - set up and verify partial csum values for packet + * @skb: the skb to set + * @start: the number of bytes after skb->data to start checksumming. + * @off: the offset from start to place the checksum. + * + * For untrusted partially-checksummed packets, we need to make sure the values + * for skb->csum_start and skb->csum_offset are valid so we don't oops. + * + * This function checks and sets those values and skb->ip_summed: if this + * returns false you should drop the packet. + */ +bool skb_partial_csum_set(struct sk_buff *skb, u16 start, u16 off) +{ + if (unlikely(start > skb_headlen(skb)) || + unlikely((int)start + off > skb_headlen(skb) - 2)) { + net_warn_ratelimited("bad partial csum: csum=%u/%u len=%u\n", + start, off, skb_headlen(skb)); + return false; + } + skb->ip_summed = CHECKSUM_PARTIAL; + skb->csum_start = skb_headroom(skb) + start; + skb->csum_offset = off; + skb_set_transport_header(skb, start); + return true; +} +EXPORT_SYMBOL_GPL(skb_partial_csum_set); + +static int skb_maybe_pull_tail(struct sk_buff *skb, unsigned int len, + unsigned int max) +{ + if (skb_headlen(skb) >= len) + return 0; + + /* If we need to pullup then pullup to the max, so we + * won't need to do it again. + */ + if (max > skb->len) + max = skb->len; + + if (__pskb_pull_tail(skb, max - skb_headlen(skb)) == NULL) + return -ENOMEM; + + if (skb_headlen(skb) < len) + return -EPROTO; + + return 0; +} + +#define MAX_TCP_HDR_LEN (15 * 4) + +static __sum16 *skb_checksum_setup_ip(struct sk_buff *skb, + typeof(IPPROTO_IP) proto, + unsigned int off) +{ + switch (proto) { + int err; + + case IPPROTO_TCP: + err = skb_maybe_pull_tail(skb, off + sizeof(struct tcphdr), + off + MAX_TCP_HDR_LEN); + if (!err && !skb_partial_csum_set(skb, off, + offsetof(struct tcphdr, + check))) + err = -EPROTO; + return err ? ERR_PTR(err) : &tcp_hdr(skb)->check; + + case IPPROTO_UDP: + err = skb_maybe_pull_tail(skb, off + sizeof(struct udphdr), + off + sizeof(struct udphdr)); + if (!err && !skb_partial_csum_set(skb, off, + offsetof(struct udphdr, + check))) + err = -EPROTO; + return err ? ERR_PTR(err) : &udp_hdr(skb)->check; + } + + return ERR_PTR(-EPROTO); +} + +/* This value should be large enough to cover a tagged ethernet header plus + * maximally sized IP and TCP or UDP headers. + */ +#define MAX_IP_HDR_LEN 128 + +static int skb_checksum_setup_ipv4(struct sk_buff *skb, bool recalculate) +{ + unsigned int off; + bool fragment; + __sum16 *csum; + int err; + + fragment = false; + + err = skb_maybe_pull_tail(skb, + sizeof(struct iphdr), + MAX_IP_HDR_LEN); + if (err < 0) + goto out; + + if (ip_hdr(skb)->frag_off & htons(IP_OFFSET | IP_MF)) + fragment = true; + + off = ip_hdrlen(skb); + + err = -EPROTO; + + if (fragment) + goto out; + + csum = skb_checksum_setup_ip(skb, ip_hdr(skb)->protocol, off); + if (IS_ERR(csum)) + return PTR_ERR(csum); + + if (recalculate) + *csum = ~csum_tcpudp_magic(ip_hdr(skb)->saddr, + ip_hdr(skb)->daddr, + skb->len - off, + ip_hdr(skb)->protocol, 0); + err = 0; + +out: + return err; +} + +/* This value should be large enough to cover a tagged ethernet header plus + * an IPv6 header, all options, and a maximal TCP or UDP header. + */ +#define MAX_IPV6_HDR_LEN 256 + +#define OPT_HDR(type, skb, off) \ + (type *)(skb_network_header(skb) + (off)) + +static int skb_checksum_setup_ipv6(struct sk_buff *skb, bool recalculate) +{ + int err; + u8 nexthdr; + unsigned int off; + unsigned int len; + bool fragment; + bool done; + __sum16 *csum; + + fragment = false; + done = false; + + off = sizeof(struct ipv6hdr); + + err = skb_maybe_pull_tail(skb, off, MAX_IPV6_HDR_LEN); + if (err < 0) + goto out; + + nexthdr = ipv6_hdr(skb)->nexthdr; + + len = sizeof(struct ipv6hdr) + ntohs(ipv6_hdr(skb)->payload_len); + while (off <= len && !done) { + switch (nexthdr) { + case IPPROTO_DSTOPTS: + case IPPROTO_HOPOPTS: + case IPPROTO_ROUTING: { + struct ipv6_opt_hdr *hp; + + err = skb_maybe_pull_tail(skb, + off + + sizeof(struct ipv6_opt_hdr), + MAX_IPV6_HDR_LEN); + if (err < 0) + goto out; + + hp = OPT_HDR(struct ipv6_opt_hdr, skb, off); + nexthdr = hp->nexthdr; + off += ipv6_optlen(hp); + break; + } + case IPPROTO_AH: { + struct ip_auth_hdr *hp; + + err = skb_maybe_pull_tail(skb, + off + + sizeof(struct ip_auth_hdr), + MAX_IPV6_HDR_LEN); + if (err < 0) + goto out; + + hp = OPT_HDR(struct ip_auth_hdr, skb, off); + nexthdr = hp->nexthdr; + off += ipv6_authlen(hp); + break; + } + case IPPROTO_FRAGMENT: { + struct frag_hdr *hp; + + err = skb_maybe_pull_tail(skb, + off + + sizeof(struct frag_hdr), + MAX_IPV6_HDR_LEN); + if (err < 0) + goto out; + + hp = OPT_HDR(struct frag_hdr, skb, off); + + if (hp->frag_off & htons(IP6_OFFSET | IP6_MF)) + fragment = true; + + nexthdr = hp->nexthdr; + off += sizeof(struct frag_hdr); + break; + } + default: + done = true; + break; + } + } + + err = -EPROTO; + + if (!done || fragment) + goto out; + + csum = skb_checksum_setup_ip(skb, nexthdr, off); + if (IS_ERR(csum)) + return PTR_ERR(csum); + + if (recalculate) + *csum = ~csum_ipv6_magic(&ipv6_hdr(skb)->saddr, + &ipv6_hdr(skb)->daddr, + skb->len - off, nexthdr, 0); + err = 0; + +out: + return err; +} + +/** + * skb_checksum_setup - set up partial checksum offset + * @skb: the skb to set up + * @recalculate: if true the pseudo-header checksum will be recalculated + */ +int skb_checksum_setup(struct sk_buff *skb, bool recalculate) +{ + int err; + + switch (skb->protocol) { + case htons(ETH_P_IP): + err = skb_checksum_setup_ipv4(skb, recalculate); + break; + + case htons(ETH_P_IPV6): + err = skb_checksum_setup_ipv6(skb, recalculate); + break; + + default: + err = -EPROTO; + break; + } + + return err; +} +EXPORT_SYMBOL(skb_checksum_setup); + +void __skb_warn_lro_forwarding(const struct sk_buff *skb) +{ + net_warn_ratelimited("%s: received packets cannot be forwarded while LRO is enabled\n", + skb->dev->name); +} +EXPORT_SYMBOL(__skb_warn_lro_forwarding); + +void kfree_skb_partial(struct sk_buff *skb, bool head_stolen) +{ + if (head_stolen) { + skb_release_head_state(skb); + kmem_cache_free(skbuff_head_cache, skb); + } else { + __kfree_skb(skb); + } +} +EXPORT_SYMBOL(kfree_skb_partial); + +/** + * skb_try_coalesce - try to merge skb to prior one + * @to: prior buffer + * @from: buffer to add + * @fragstolen: pointer to boolean + * @delta_truesize: how much more was allocated than was requested + */ +bool skb_try_coalesce(struct sk_buff *to, struct sk_buff *from, + bool *fragstolen, int *delta_truesize) +{ + int i, delta, len = from->len; + + *fragstolen = false; + + if (skb_cloned(to)) + return false; + + if (len <= skb_tailroom(to)) { + if (len) + BUG_ON(skb_copy_bits(from, 0, skb_put(to, len), len)); + *delta_truesize = 0; + return true; + } + + if (skb_has_frag_list(to) || skb_has_frag_list(from)) + return false; + + if (skb_headlen(from) != 0) { + struct page *page; + unsigned int offset; + + if (skb_shinfo(to)->nr_frags + + skb_shinfo(from)->nr_frags >= MAX_SKB_FRAGS) + return false; + + if (skb_head_is_locked(from)) + return false; + + delta = from->truesize - SKB_DATA_ALIGN(sizeof(struct sk_buff)); + + page = virt_to_head_page(from->head); + offset = from->data - (unsigned char *)page_address(page); + + skb_fill_page_desc(to, skb_shinfo(to)->nr_frags, + page, offset, skb_headlen(from)); + *fragstolen = true; + } else { + if (skb_shinfo(to)->nr_frags + + skb_shinfo(from)->nr_frags > MAX_SKB_FRAGS) + return false; + + delta = from->truesize - SKB_TRUESIZE(skb_end_offset(from)); + } + + WARN_ON_ONCE(delta < len); + + memcpy(skb_shinfo(to)->frags + skb_shinfo(to)->nr_frags, + skb_shinfo(from)->frags, + skb_shinfo(from)->nr_frags * sizeof(skb_frag_t)); + skb_shinfo(to)->nr_frags += skb_shinfo(from)->nr_frags; + + if (!skb_cloned(from)) + skb_shinfo(from)->nr_frags = 0; + + /* if the skb is not cloned this does nothing + * since we set nr_frags to 0. + */ + for (i = 0; i < skb_shinfo(from)->nr_frags; i++) + skb_frag_ref(from, i); + + to->truesize += delta; + to->len += len; + to->data_len += len; + + *delta_truesize = delta; + return true; +} +EXPORT_SYMBOL(skb_try_coalesce); + +/** + * skb_scrub_packet - scrub an skb + * + * @skb: buffer to clean + * @xnet: packet is crossing netns + * + * skb_scrub_packet can be used after encapsulating or decapsulting a packet + * into/from a tunnel. Some information have to be cleared during these + * operations. + * skb_scrub_packet can also be used to clean a skb before injecting it in + * another namespace (@xnet == true). We have to clear all information in the + * skb that could impact namespace isolation. + */ +void skb_scrub_packet(struct sk_buff *skb, bool xnet) +{ + skb->tstamp.tv64 = 0; + skb->pkt_type = PACKET_HOST; + skb->skb_iif = 0; + skb->ignore_df = 0; + skb_dst_drop(skb); + secpath_reset(skb); + nf_reset(skb); + nf_reset_trace(skb); + + if (!xnet) + return; + + skb_orphan(skb); + skb->mark = 0; +} +EXPORT_SYMBOL_GPL(skb_scrub_packet); + +/** + * skb_gso_transport_seglen - Return length of individual segments of a gso packet + * + * @skb: GSO skb + * + * skb_gso_transport_seglen is used to determine the real size of the + * individual segments, including Layer4 headers (TCP/UDP). + * + * The MAC/L2 or network (IP, IPv6) headers are not accounted for. + */ +unsigned int skb_gso_transport_seglen(const struct sk_buff *skb) +{ + const struct skb_shared_info *shinfo = skb_shinfo(skb); + unsigned int thlen = 0; + + if (skb->encapsulation) { + thlen = skb_inner_transport_header(skb) - + skb_transport_header(skb); + + if (likely(shinfo->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6))) + thlen += inner_tcp_hdrlen(skb); + } else if (likely(shinfo->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6))) { + thlen = tcp_hdrlen(skb); + } + /* UFO sets gso_size to the size of the fragmentation + * payload, i.e. the size of the L4 (UDP) header is already + * accounted for. + */ + return thlen + shinfo->gso_size; +} +EXPORT_SYMBOL_GPL(skb_gso_transport_seglen); + +static struct sk_buff *skb_reorder_vlan_header(struct sk_buff *skb) +{ + if (skb_cow(skb, skb_headroom(skb)) < 0) { + kfree_skb(skb); + return NULL; + } + + memmove(skb->data - ETH_HLEN, skb->data - VLAN_ETH_HLEN, 2 * ETH_ALEN); + skb->mac_header += VLAN_HLEN; + return skb; +} + +struct sk_buff *skb_vlan_untag(struct sk_buff *skb) +{ + struct vlan_hdr *vhdr; + u16 vlan_tci; + + if (unlikely(vlan_tx_tag_present(skb))) { + /* vlan_tci is already set-up so leave this for another time */ + return skb; + } + + skb = skb_share_check(skb, GFP_ATOMIC); + if (unlikely(!skb)) + goto err_free; + + if (unlikely(!pskb_may_pull(skb, VLAN_HLEN))) + goto err_free; + + vhdr = (struct vlan_hdr *)skb->data; + vlan_tci = ntohs(vhdr->h_vlan_TCI); + __vlan_hwaccel_put_tag(skb, skb->protocol, vlan_tci); + + skb_pull_rcsum(skb, VLAN_HLEN); + vlan_set_encap_proto(skb, vhdr); + + skb = skb_reorder_vlan_header(skb); + if (unlikely(!skb)) + goto err_free; + + skb_reset_network_header(skb); + skb_reset_transport_header(skb); + skb_reset_mac_len(skb); + + return skb; + +err_free: + kfree_skb(skb); + return NULL; +} +EXPORT_SYMBOL(skb_vlan_untag); + +/** + * alloc_skb_with_frags - allocate skb with page frags + * + * @header_len: size of linear part + * @data_len: needed length in frags + * @max_page_order: max page order desired. + * @errcode: pointer to error code if any + * @gfp_mask: allocation mask + * + * This can be used to allocate a paged skb, given a maximal order for frags. + */ +struct sk_buff *alloc_skb_with_frags(unsigned long header_len, + unsigned long data_len, + int max_page_order, + int *errcode, + gfp_t gfp_mask) +{ + int npages = (data_len + (PAGE_SIZE - 1)) >> PAGE_SHIFT; + unsigned long chunk; + struct sk_buff *skb; + struct page *page; + gfp_t gfp_head; + int i; + + *errcode = -EMSGSIZE; + /* Note this test could be relaxed, if we succeed to allocate + * high order pages... + */ + if (npages > MAX_SKB_FRAGS) + return NULL; + + gfp_head = gfp_mask; + if (gfp_head & __GFP_WAIT) + gfp_head |= __GFP_REPEAT; + + *errcode = -ENOBUFS; + skb = alloc_skb(header_len, gfp_head); + if (!skb) + return NULL; + + skb->truesize += npages << PAGE_SHIFT; + + for (i = 0; npages > 0; i++) { + int order = max_page_order; + + while (order) { + if (npages >= 1 << order) { + page = alloc_pages(gfp_mask | + __GFP_COMP | + __GFP_NOWARN | + __GFP_NORETRY, + order); + if (page) + goto fill_page; + /* Do not retry other high order allocations */ + order = 1; + max_page_order = 0; + } + order--; + } + page = alloc_page(gfp_mask); + if (!page) + goto failure; +fill_page: + chunk = min_t(unsigned long, data_len, + PAGE_SIZE << order); + skb_fill_page_desc(skb, i, page, 0, chunk); + data_len -= chunk; + npages -= 1 << order; + } + return skb; + +failure: + kfree_skb(skb); + return NULL; +} +EXPORT_SYMBOL(alloc_skb_with_frags); diff -Nur linux-3.18.14.orig/net/core/sock.c linux-3.18.14-rt/net/core/sock.c --- linux-3.18.14.orig/net/core/sock.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/net/core/sock.c 2015-05-31 15:32:49.433635358 -0500 @@ -2345,12 +2345,11 @@ if (sk->sk_lock.owned) __lock_sock(sk); sk->sk_lock.owned = 1; - spin_unlock(&sk->sk_lock.slock); + spin_unlock_bh(&sk->sk_lock.slock); /* * The sk_lock has mutex_lock() semantics here: */ mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_); - local_bh_enable(); } EXPORT_SYMBOL(lock_sock_nested); diff -Nur linux-3.18.14.orig/net/ipv4/icmp.c linux-3.18.14-rt/net/ipv4/icmp.c --- linux-3.18.14.orig/net/ipv4/icmp.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/net/ipv4/icmp.c 2015-05-31 15:32:49.457635357 -0500 @@ -69,6 +69,7 @@ #include #include #include +#include #include #include #include @@ -864,6 +865,30 @@ } /* + * 32bit and 64bit have different timestamp length, so we check for + * the cookie at offset 20 and verify it is repeated at offset 50 + */ +#define CO_POS0 20 +#define CO_POS1 50 +#define CO_SIZE sizeof(int) +#define ICMP_SYSRQ_SIZE 57 + +/* + * We got a ICMP_SYSRQ_SIZE sized ping request. Check for the cookie + * pattern and if it matches send the next byte as a trigger to sysrq. + */ +static void icmp_check_sysrq(struct net *net, struct sk_buff *skb) +{ + int cookie = htonl(net->ipv4.sysctl_icmp_echo_sysrq); + char *p = skb->data; + + if (!memcmp(&cookie, p + CO_POS0, CO_SIZE) && + !memcmp(&cookie, p + CO_POS1, CO_SIZE) && + p[CO_POS0 + CO_SIZE] == p[CO_POS1 + CO_SIZE]) + handle_sysrq(p[CO_POS0 + CO_SIZE]); +} + +/* * Handle ICMP_ECHO ("ping") requests. * * RFC 1122: 3.2.2.6 MUST have an echo server that answers ICMP echo @@ -890,6 +915,11 @@ icmp_param.data_len = skb->len; icmp_param.head_len = sizeof(struct icmphdr); icmp_reply(&icmp_param, skb); + + if (skb->len == ICMP_SYSRQ_SIZE && + net->ipv4.sysctl_icmp_echo_sysrq) { + icmp_check_sysrq(net, skb); + } } } diff -Nur linux-3.18.14.orig/net/ipv4/sysctl_net_ipv4.c linux-3.18.14-rt/net/ipv4/sysctl_net_ipv4.c --- linux-3.18.14.orig/net/ipv4/sysctl_net_ipv4.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/net/ipv4/sysctl_net_ipv4.c 2015-05-31 15:32:49.485635357 -0500 @@ -779,6 +779,13 @@ .proc_handler = proc_dointvec }, { + .procname = "icmp_echo_sysrq", + .data = &init_net.ipv4.sysctl_icmp_echo_sysrq, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec + }, + { .procname = "icmp_ignore_bogus_error_responses", .data = &init_net.ipv4.sysctl_icmp_ignore_bogus_error_responses, .maxlen = sizeof(int), diff -Nur linux-3.18.14.orig/net/mac80211/rx.c linux-3.18.14-rt/net/mac80211/rx.c --- linux-3.18.14.orig/net/mac80211/rx.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/net/mac80211/rx.c 2015-05-31 15:32:49.501635357 -0500 @@ -3360,7 +3360,7 @@ struct ieee80211_supported_band *sband; struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb); - WARN_ON_ONCE(softirq_count() == 0); + WARN_ON_ONCE_NONRT(softirq_count() == 0); if (WARN_ON(status->band >= IEEE80211_NUM_BANDS)) goto drop; diff -Nur linux-3.18.14.orig/net/netfilter/core.c linux-3.18.14-rt/net/netfilter/core.c --- linux-3.18.14.orig/net/netfilter/core.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/net/netfilter/core.c 2015-05-31 15:32:49.549635357 -0500 @@ -21,11 +21,17 @@ #include #include #include +#include #include #include #include "nf_internals.h" +#ifdef CONFIG_PREEMPT_RT_BASE +DEFINE_LOCAL_IRQ_LOCK(xt_write_lock); +EXPORT_PER_CPU_SYMBOL(xt_write_lock); +#endif + static DEFINE_MUTEX(afinfo_mutex); const struct nf_afinfo __rcu *nf_afinfo[NFPROTO_NUMPROTO] __read_mostly; diff -Nur linux-3.18.14.orig/net/packet/af_packet.c linux-3.18.14-rt/net/packet/af_packet.c --- linux-3.18.14.orig/net/packet/af_packet.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/net/packet/af_packet.c 2015-05-31 15:32:49.557635357 -0500 @@ -63,6 +63,7 @@ #include #include #include +#include #include #include #include @@ -692,7 +693,7 @@ if (BLOCK_NUM_PKTS(pbd)) { while (atomic_read(&pkc->blk_fill_in_prog)) { /* Waiting for skb_copy_bits to finish... */ - cpu_relax(); + cpu_chill(); } } @@ -943,7 +944,7 @@ if (!(status & TP_STATUS_BLK_TMO)) { while (atomic_read(&pkc->blk_fill_in_prog)) { /* Waiting for skb_copy_bits to finish... */ - cpu_relax(); + cpu_chill(); } } prb_close_block(pkc, pbd, po, status); diff -Nur linux-3.18.14.orig/net/rds/ib_rdma.c linux-3.18.14-rt/net/rds/ib_rdma.c --- linux-3.18.14.orig/net/rds/ib_rdma.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/net/rds/ib_rdma.c 2015-05-31 15:32:49.573635357 -0500 @@ -34,6 +34,7 @@ #include #include #include +#include #include "rds.h" #include "ib.h" @@ -286,7 +287,7 @@ for_each_online_cpu(cpu) { flag = &per_cpu(clean_list_grace, cpu); while (test_bit(CLEAN_LIST_BUSY_BIT, flag)) - cpu_relax(); + cpu_chill(); } } diff -Nur linux-3.18.14.orig/net/sched/sch_generic.c linux-3.18.14-rt/net/sched/sch_generic.c --- linux-3.18.14.orig/net/sched/sch_generic.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/net/sched/sch_generic.c 2015-05-31 15:32:49.593635356 -0500 @@ -894,7 +894,7 @@ /* Wait for outstanding qdisc_run calls. */ list_for_each_entry(dev, head, close_list) while (some_qdisc_is_busy(dev)) - yield(); + msleep(1); } void dev_deactivate(struct net_device *dev) diff -Nur linux-3.18.14.orig/net/sunrpc/svc_xprt.c linux-3.18.14-rt/net/sunrpc/svc_xprt.c --- linux-3.18.14.orig/net/sunrpc/svc_xprt.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/net/sunrpc/svc_xprt.c 2015-05-31 15:32:49.617635356 -0500 @@ -357,7 +357,7 @@ return; } - cpu = get_cpu(); + cpu = get_cpu_light(); pool = svc_pool_for_cpu(xprt->xpt_server, cpu); spin_lock_bh(&pool->sp_lock); @@ -390,7 +390,7 @@ } spin_unlock_bh(&pool->sp_lock); - put_cpu(); + put_cpu_light(); } /* diff -Nur linux-3.18.14.orig/scripts/mkcompile_h linux-3.18.14-rt/scripts/mkcompile_h --- linux-3.18.14.orig/scripts/mkcompile_h 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/scripts/mkcompile_h 2015-05-31 15:32:49.641635356 -0500 @@ -4,7 +4,8 @@ ARCH=$2 SMP=$3 PREEMPT=$4 -CC=$5 +RT=$5 +CC=$6 vecho() { [ "${quiet}" = "silent_" ] || echo "$@" ; } @@ -57,6 +58,7 @@ CONFIG_FLAGS="" if [ -n "$SMP" ] ; then CONFIG_FLAGS="SMP"; fi if [ -n "$PREEMPT" ] ; then CONFIG_FLAGS="$CONFIG_FLAGS PREEMPT"; fi +if [ -n "$RT" ] ; then CONFIG_FLAGS="$CONFIG_FLAGS RT"; fi UTS_VERSION="$UTS_VERSION $CONFIG_FLAGS $TIMESTAMP" # Truncate to maximum length diff -Nur linux-3.18.14.orig/sound/core/pcm_native.c linux-3.18.14-rt/sound/core/pcm_native.c --- linux-3.18.14.orig/sound/core/pcm_native.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/sound/core/pcm_native.c 2015-05-31 15:32:49.661635356 -0500 @@ -104,7 +104,7 @@ void snd_pcm_stream_lock_irq(struct snd_pcm_substream *substream) { if (!substream->pcm->nonatomic) - local_irq_disable(); + local_irq_disable_nort(); snd_pcm_stream_lock(substream); } EXPORT_SYMBOL_GPL(snd_pcm_stream_lock_irq); @@ -113,7 +113,7 @@ { snd_pcm_stream_unlock(substream); if (!substream->pcm->nonatomic) - local_irq_enable(); + local_irq_enable_nort(); } EXPORT_SYMBOL_GPL(snd_pcm_stream_unlock_irq); @@ -121,7 +121,7 @@ { unsigned long flags = 0; if (!substream->pcm->nonatomic) - local_irq_save(flags); + local_irq_save_nort(flags); snd_pcm_stream_lock(substream); return flags; } @@ -132,7 +132,7 @@ { snd_pcm_stream_unlock(substream); if (!substream->pcm->nonatomic) - local_irq_restore(flags); + local_irq_restore_nort(flags); } EXPORT_SYMBOL_GPL(snd_pcm_stream_unlock_irqrestore); diff -Nur linux-3.18.14.orig/virt/kvm/async_pf.c linux-3.18.14-rt/virt/kvm/async_pf.c --- linux-3.18.14.orig/virt/kvm/async_pf.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/virt/kvm/async_pf.c 2015-05-31 15:32:49.661635356 -0500 @@ -94,8 +94,8 @@ trace_kvm_async_pf_completed(addr, gva); - if (waitqueue_active(&vcpu->wq)) - wake_up_interruptible(&vcpu->wq); + if (swaitqueue_active(&vcpu->wq)) + swait_wake_interruptible(&vcpu->wq); mmput(mm); kvm_put_kvm(vcpu->kvm); diff -Nur linux-3.18.14.orig/virt/kvm/kvm_main.c linux-3.18.14-rt/virt/kvm/kvm_main.c --- linux-3.18.14.orig/virt/kvm/kvm_main.c 2015-05-20 10:04:50.000000000 -0500 +++ linux-3.18.14-rt/virt/kvm/kvm_main.c 2015-05-31 15:32:49.697635356 -0500 @@ -221,7 +221,7 @@ vcpu->kvm = kvm; vcpu->vcpu_id = id; vcpu->pid = NULL; - init_waitqueue_head(&vcpu->wq); + init_swait_head(&vcpu->wq); kvm_async_pf_vcpu_init(vcpu); page = alloc_page(GFP_KERNEL | __GFP_ZERO); @@ -1741,10 +1741,10 @@ */ void kvm_vcpu_block(struct kvm_vcpu *vcpu) { - DEFINE_WAIT(wait); + DEFINE_SWAITER(wait); for (;;) { - prepare_to_wait(&vcpu->wq, &wait, TASK_INTERRUPTIBLE); + swait_prepare(&vcpu->wq, &wait, TASK_INTERRUPTIBLE); if (kvm_arch_vcpu_runnable(vcpu)) { kvm_make_request(KVM_REQ_UNHALT, vcpu); @@ -1758,7 +1758,7 @@ schedule(); } - finish_wait(&vcpu->wq, &wait); + swait_finish(&vcpu->wq, &wait); } EXPORT_SYMBOL_GPL(kvm_vcpu_block); @@ -1770,11 +1770,11 @@ { int me; int cpu = vcpu->cpu; - wait_queue_head_t *wqp; + struct swait_head *wqp; wqp = kvm_arch_vcpu_wq(vcpu); - if (waitqueue_active(wqp)) { - wake_up_interruptible(wqp); + if (swaitqueue_active(wqp)) { + swait_wake_interruptible(wqp); ++vcpu->stat.halt_wakeup; } @@ -1879,7 +1879,7 @@ continue; if (vcpu == me) continue; - if (waitqueue_active(&vcpu->wq) && !kvm_arch_vcpu_runnable(vcpu)) + if (swaitqueue_active(&vcpu->wq) && !kvm_arch_vcpu_runnable(vcpu)) continue; if (!kvm_vcpu_eligible_for_directed_yield(vcpu)) continue;