diff options
Diffstat (limited to 'libpthread/linuxthreads/sysdeps/i386')
| -rw-r--r-- | libpthread/linuxthreads/sysdeps/i386/i686/pt-machine.h | 78 | ||||
| -rw-r--r-- | libpthread/linuxthreads/sysdeps/i386/pspinlock.c | 102 | ||||
| -rw-r--r-- | libpthread/linuxthreads/sysdeps/i386/pt-machine.h | 93 | ||||
| -rw-r--r-- | libpthread/linuxthreads/sysdeps/i386/tcb-offsets.sym | 7 | ||||
| -rw-r--r-- | libpthread/linuxthreads/sysdeps/i386/tls.h | 84 | ||||
| -rw-r--r-- | libpthread/linuxthreads/sysdeps/i386/useldt.h | 19 |
6 files changed, 88 insertions, 295 deletions
diff --git a/libpthread/linuxthreads/sysdeps/i386/i686/pt-machine.h b/libpthread/linuxthreads/sysdeps/i386/i686/pt-machine.h deleted file mode 100644 index 2e52abe2e..000000000 --- a/libpthread/linuxthreads/sysdeps/i386/i686/pt-machine.h +++ /dev/null @@ -1,78 +0,0 @@ -/* Machine-dependent pthreads configuration and inline functions. - i686 version. - Copyright (C) 1996-2001, 2002, 2003 Free Software Foundation, Inc. - This file is part of the GNU C Library. - Contributed by Richard Henderson <rth@tamu.edu>. - - The GNU C Library is free software; you can redistribute it and/or - modify it under the terms of the GNU Lesser General Public License as - published by the Free Software Foundation; either version 2.1 of the - License, or (at your option) any later version. - - The GNU C Library 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 - Lesser General Public License for more details. - - You should have received a copy of the GNU Lesser General Public - License along with the GNU C Library; see the file COPYING.LIB. If - not, see <http://www.gnu.org/licenses/>. */ - -#ifndef _PT_MACHINE_H -#define _PT_MACHINE_H 1 - -#ifndef PT_EI -# define PT_EI __extern_always_inline -#endif -#include <bits/kernel-features.h> - -#ifndef __ASSEMBLER__ -extern long int testandset (int *spinlock); -extern int __compare_and_swap (long int *p, long int oldval, long int newval); - -/* Get some notion of the current stack. Need not be exactly the top - of the stack, just something somewhere in the current frame. */ -#define CURRENT_STACK_FRAME __builtin_frame_address (0) - - -/* Spinlock implementation; required. */ -PT_EI long int -testandset (int *spinlock) -{ - long int ret; - - __asm__ __volatile__ ( - "xchgl %0, %1" - : "=r" (ret), "=m" (*spinlock) - : "0" (1), "m" (*spinlock) - : "memory"); - - return ret; -} - - -/* Compare-and-swap for semaphores. It's always available on i686. */ -#define HAS_COMPARE_AND_SWAP - -PT_EI int -__compare_and_swap (long int *p, long int oldval, long int newval) -{ - char ret; - long int readval; - - __asm__ __volatile__ ("lock; cmpxchgl %3, %1; sete %0" - : "=q" (ret), "=m" (*p), "=a" (readval) - : "r" (newval), "m" (*p), "a" (oldval) - : "memory"); - return ret; -} -#endif - -#if __ASSUME_LDT_WORKS > 0 -#include "../useldt.h" -#endif - -/* The P4 and above really want some help to prevent overheating. */ -#define BUSY_WAIT_NOP __asm__ ("rep; nop") - -#endif /* pt-machine.h */ diff --git a/libpthread/linuxthreads/sysdeps/i386/pspinlock.c b/libpthread/linuxthreads/sysdeps/i386/pspinlock.c deleted file mode 100644 index 7936735f9..000000000 --- a/libpthread/linuxthreads/sysdeps/i386/pspinlock.c +++ /dev/null @@ -1,102 +0,0 @@ -/* POSIX spinlock implementation. x86 version. - Copyright (C) 2000, 2002, 2006 Free Software Foundation, Inc. - This file is part of the GNU C Library. - - The GNU C Library is free software; you can redistribute it and/or - modify it under the terms of the GNU Lesser General Public License as - published by the Free Software Foundation; either version 2.1 of the - License, or (at your option) any later version. - - The GNU C Library 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 - Lesser General Public License for more details. - - You should have received a copy of the GNU Lesser General Public - License along with the GNU C Library; see the file COPYING.LIB. If - not, see <http://www.gnu.org/licenses/>. */ - -#include <errno.h> -#include <pthread.h> -#include "internals.h" -#include <bits/kernel-features.h> - - -/* This implementation is similar to the one used in the Linux kernel. - But the kernel is byte instructions for the memory access. This is - faster but unusable here. The problem is that only 128 - threads/processes could use the spinlock at the same time. If (by - a design error in the program) a thread/process would hold the - spinlock for a time long enough to accumulate 128 waiting - processes, the next one will find a positive value in the spinlock - and assume it is unlocked. We cannot accept that. */ - -int -__pthread_spin_lock (pthread_spinlock_t *lock) -{ - __asm__ __volatile__ - ("\n" - "1:\n\t" - "lock; decl %0\n\t" - "js 2f\n\t" - ".section .text.spinlock,\"ax\"\n" - "2:\n\t" - "cmpl $0,%0\n\t" - "rep; nop\n\t" - "jle 2b\n\t" - "jmp 1b\n\t" - ".previous" - : "=m" (*lock)); - return 0; -} -weak_alias (__pthread_spin_lock, pthread_spin_lock) - - -int -__pthread_spin_trylock (pthread_spinlock_t *lock) -{ - int oldval; - - __asm__ __volatile__ - ("xchgl %0,%1" - : "=r" (oldval), "=m" (*lock) - : "0" (0)); - return oldval > 0 ? 0 : EBUSY; -} -weak_alias (__pthread_spin_trylock, pthread_spin_trylock) - - -int -__pthread_spin_unlock (pthread_spinlock_t *lock) -{ - __asm__ __volatile__ - ("movl $1,%0" - : "=m" (*lock)); - return 0; -} -weak_alias (__pthread_spin_unlock, pthread_spin_unlock) - - -int -__pthread_spin_init (pthread_spinlock_t *lock, int pshared) -{ - /* We can ignore the `pshared' parameter. Since we are busy-waiting - all processes which can access the memory location `lock' points - to can use the spinlock. */ - *lock = 1; - return 0; -} -weak_alias (__pthread_spin_init, pthread_spin_init) - - -int -__pthread_spin_destroy (pthread_spinlock_t *lock) -{ - /* Nothing to do. */ - return 0; -} -weak_alias (__pthread_spin_destroy, pthread_spin_destroy) - -#ifndef __ASSUME_SET_THREAD_AREA_SYSCALL -int __have_no_set_thread_area; -#endif diff --git a/libpthread/linuxthreads/sysdeps/i386/pt-machine.h b/libpthread/linuxthreads/sysdeps/i386/pt-machine.h index 82a5cf077..24c5e6c7c 100644 --- a/libpthread/linuxthreads/sysdeps/i386/pt-machine.h +++ b/libpthread/linuxthreads/sysdeps/i386/pt-machine.h @@ -18,17 +18,14 @@ License along with the GNU C Library; see the file COPYING.LIB. If not, see <http://www.gnu.org/licenses/>. */ -#if defined __pentiumpro__ || defined __pentium4__ || defined __athlon__ || \ - defined __k8__ -# include "i686/pt-machine.h" -#else - #ifndef _PT_MACHINE_H #define _PT_MACHINE_H 1 +#include <features.h> + #ifndef __ASSEMBLER__ #ifndef PT_EI -# define PT_EI __extern_always_inline +# define PT_EI __extern_always_inline __attribute__((visibility("hidden"))) #endif extern long int testandset (int *spinlock); @@ -39,6 +36,54 @@ extern int __compare_and_swap (long int *p, long int oldval, long int newval); #define CURRENT_STACK_FRAME __builtin_frame_address (0) +/* See if we can optimize for newer cpus... */ +#if defined __GNUC__ && __GNUC__ >= 2 && \ + (defined __i486__ || defined __pentium__ || defined __pentiumpro__ || defined __pentium4__ || \ + defined __athlon__ || defined __k8__) + +/* Spinlock implementation; required. */ +PT_EI long int +testandset (int *spinlock) +{ + long int ret; + + __asm__ __volatile__ ( + "xchgl %0, %1" + : "=r" (ret), "=m" (*spinlock) + : "0" (1), "m" (*spinlock) + : "memory"); + + return ret; +} + +/* Compare-and-swap for semaphores. It's always available on i686. */ +#define HAS_COMPARE_AND_SWAP + +PT_EI int +__compare_and_swap (long int *p, long int oldval, long int newval) +{ + char ret; + long int readval; + + __asm__ __volatile__ ("lock; cmpxchgl %3, %1; sete %0" + : "=q" (ret), "=m" (*p), "=a" (readval) + : "r" (newval), "m" (*p), "a" (oldval) + : "memory"); + return ret; +} + +#if defined(__ASSUME_LDT_WORKS) && __ASSUME_LDT_WORKS > 0 +#include "useldt.h" +#endif + +/* The P4 and above really want some help to prevent overheating. */ +#define BUSY_WAIT_NOP __asm__ ("rep; nop") + + +#else /* Generic i386 implementation */ + +extern int compare_and_swap_is_available (void); + /* Spinlock implementation; required. */ PT_EI long int testandset (int *spinlock) @@ -75,43 +120,27 @@ __compare_and_swap (long int *p, long int oldval, long int newval) return ret; } - -PT_EI int get_eflags (void); -PT_EI int -get_eflags (void) -{ - int res; - __asm__ __volatile__ ("pushfl; popl %0" : "=r" (res) : ); - return res; -} - - -PT_EI void set_eflags (int newflags); -PT_EI void -set_eflags (int newflags) -{ - __asm__ __volatile__ ("pushl %0; popfl" : : "r" (newflags) : "cc"); -} - - -PT_EI int compare_and_swap_is_available (void); PT_EI int compare_and_swap_is_available (void) { - int oldflags = get_eflags (); int changed; + int oldflags; + /* get EFLAGS */ + __asm__ __volatile__ ("pushfl; popl %0" : "=r" (oldflags) : ); /* Flip AC bit in EFLAGS. */ - set_eflags (oldflags ^ 0x40000); + __asm__ __volatile__ ("pushl %0; popfl" : : "r" (oldflags ^ 0x40000) : "cc"); + /* reread EFLAGS */ + __asm__ __volatile__ ("pushfl; popl %0" : "=r" (changed) : ); /* See if bit changed. */ - changed = (get_eflags () ^ oldflags) & 0x40000; + changed = (changed ^ oldflags) & 0x40000; /* Restore EFLAGS. */ - set_eflags (oldflags); + __asm__ __volatile__ ("pushl %0; popfl" : : "r" (oldflags) : "cc"); /* If the AC flag did not change, it's a 386 and it lacks cmpxchg. Otherwise, it's a 486 or above and it has cmpxchg. */ return changed != 0; } +#endif /* Generic i386 implementation */ + #endif /* __ASSEMBLER__ */ #endif /* pt-machine.h */ - -#endif diff --git a/libpthread/linuxthreads/sysdeps/i386/tcb-offsets.sym b/libpthread/linuxthreads/sysdeps/i386/tcb-offsets.sym deleted file mode 100644 index 69a5018d8..000000000 --- a/libpthread/linuxthreads/sysdeps/i386/tcb-offsets.sym +++ /dev/null @@ -1,7 +0,0 @@ -#include <sysdep.h> -#include <tls.h> - -MULTIPLE_THREADS_OFFSET offsetof (tcbhead_t, multiple_threads) -#ifdef NEED_DL_SYSINFO -SYSINFO_OFFSET offsetof (tcbhead_t, sysinfo) -#endif diff --git a/libpthread/linuxthreads/sysdeps/i386/tls.h b/libpthread/linuxthreads/sysdeps/i386/tls.h index d79bf0779..4469f0776 100644 --- a/libpthread/linuxthreads/sysdeps/i386/tls.h +++ b/libpthread/linuxthreads/sysdeps/i386/tls.h @@ -30,11 +30,7 @@ typedef union dtv { size_t counter; - struct - { - void *val; - bool is_static; - } pointer; + void *pointer; } dtv_t; @@ -44,28 +40,15 @@ typedef struct thread descriptor used by libpthread. */ dtv_t *dtv; void *self; /* Pointer to the thread descriptor. */ - int multiple_threads; - uintptr_t sysinfo; } tcbhead_t; - -#else /* __ASSEMBLER__ */ -# include <tcb-offsets.h> #endif -/* We can support TLS only if the floating-stack support is available. - However, we want to compile in the support and test at runtime whether - the running kernel can support it or not. To avoid bothering with the - TLS support code at all, use configure --without-tls. - - We need USE_TLS to be consistently defined, for ldsodefs.h conditionals. - But some of the code below can cause problems in building libpthread - (e.g. useldt.h will defined FLOATING_STACKS when it shouldn't). */ -#if defined HAVE_TLS_SUPPORT \ - && (defined FLOATING_STACKS || !defined IS_IN_libpthread) +/* We can support TLS only if the floating-stack support is available. */ +#if defined FLOATING_STACKS && defined HAVE_TLS_SUPPORT /* Signal that TLS support is available. */ -# define USE_TLS 1 +//# define USE_TLS 1 # ifndef __ASSEMBLER__ /* Get system call information. */ @@ -114,20 +97,7 @@ typedef struct # define TLS_LOAD_EBX # endif -# if !defined IS_IN_libpthread && !defined DO_MODIFY_LDT -# include "useldt.h" /* For the structure. */ -# endif -# if __ASSUME_LDT_WORKS > 0 -# define TLS_DO_MODIFY_LDT_KERNEL_CHECK(doit) (doit) /* Nothing to check. */ -# else -# define TLS_DO_MODIFY_LDT_KERNEL_CHECK(doit) \ - (__builtin_expect (GLRO(dl_osversion) < 131939, 0) \ - ? "kernel too old for thread-local storage support\n" \ - : (doit)) -# endif - # define TLS_DO_MODIFY_LDT(descr, nr) \ -TLS_DO_MODIFY_LDT_KERNEL_CHECK( \ ({ \ struct modify_ldt_ldt_s ldt_entry = \ { nr, (unsigned long int) (descr), 0xfffff /* 4GB in pages */, \ @@ -143,10 +113,8 @@ TLS_DO_MODIFY_LDT_KERNEL_CHECK( \ here. */ \ "m" (ldt_entry), TLS_EBX_ARG (1), "c" (&ldt_entry), \ "d" (sizeof (ldt_entry))); \ - __builtin_expect (result, 0) == 0 \ - ? ({ __asm__ ("movw %w0, %%gs" : : "q" ((nr) * 8 + 7)); NULL; }) \ - : "cannot set up LDT for thread-local storage\n"; \ -})) + __builtin_expect (result, 0) != 0 ? -1 : nr * 8 + 7; \ +}) # define TLS_DO_SET_THREAD_AREA(descr, secondcall) \ ({ \ @@ -167,60 +135,50 @@ TLS_DO_MODIFY_LDT_KERNEL_CHECK( \ to let the compiler know that we are accessing LDT_ENTRY \ here. */ \ TLS_EBX_ARG (&ldt_entry), "m" (ldt_entry)); \ - if (__builtin_expect (result, 0) == 0) \ - __asm__ ("movw %w0, %%gs" : : "q" (ldt_entry.entry_number * 8 + 3)); \ - result; \ + __builtin_expect (result, 0) == 0 ? ldt_entry.entry_number * 8 + 3 : -1; \ }) # ifdef __ASSUME_SET_THREAD_AREA_SYSCALL -# define TLS_SETUP_GS_SEGMENT(descr, secondcall) \ - (TLS_DO_SET_THREAD_AREA (descr, secondcall) \ - ? "set_thread_area failed when setting up thread-local storage\n" : NULL) +# define TLS_SETUP_GS_SEGMENT(descr, secondcall) \ + TLS_DO_SET_THREAD_AREA (descr, firstcall) # elif defined __NR_set_thread_area # define TLS_SETUP_GS_SEGMENT(descr, secondcall) \ - (TLS_DO_SET_THREAD_AREA (descr, secondcall) \ - ? TLS_DO_MODIFY_LDT (descr, 0) : NULL) + ({ int __seg = TLS_DO_SET_THREAD_AREA (descr, secondcall); \ + __seg == -1 ? TLS_DO_MODIFY_LDT (descr, 0) : __seg; }) # else # define TLS_SETUP_GS_SEGMENT(descr, secondcall) \ TLS_DO_MODIFY_LDT ((descr), 0) # endif -#if defined NEED_DL_SYSINFO -# define INIT_SYSINFO \ - head->sysinfo = GLRO(dl_sysinfo) -#else -# define INIT_SYSINFO -#endif - /* Code to initially initialize the thread pointer. This might need special attention since 'errno' is not yet available and if the - operation can cause a failure 'errno' must not be touched. - - The value of this macro is null if successful, or an error string. */ + operation can cause a failure 'errno' must not be touched. */ # define TLS_INIT_TP(descr, secondcall) \ ({ \ void *_descr = (descr); \ tcbhead_t *head = _descr; \ + int __gs; \ \ head->tcb = _descr; \ /* For now the thread descriptor is at the same address. */ \ head->self = _descr; \ \ - INIT_SYSINFO; \ - TLS_SETUP_GS_SEGMENT (_descr, secondcall); \ + __gs = TLS_SETUP_GS_SEGMENT (_descr, secondcall); \ + if (__builtin_expect (__gs, 7) != -1) \ + { \ + __asm__ ("movw %w0, %%gs" : : "q" (__gs)); \ + __gs = 0; \ + } \ + __gs; \ }) -/* Indicate that dynamic linker shouldn't try to initialize TLS even - when no PT_TLS segments are found in the program and libraries - it is linked against. */ -# define TLS_INIT_TP_EXPENSIVE 1 /* Return the address of the dtv for the current thread. */ # define THREAD_DTV() \ ({ struct _pthread_descr_struct *__descr; \ THREAD_GETMEM (__descr, p_header.data.dtvp); }) -# endif /* HAVE_TLS_SUPPORT && (FLOATING_STACKS || !IS_IN_libpthread) */ +# endif /* FLOATING_STACKS && HAVE_TLS_SUPPORT */ #endif /* __ASSEMBLER__ */ #endif /* tls.h */ diff --git a/libpthread/linuxthreads/sysdeps/i386/useldt.h b/libpthread/linuxthreads/sysdeps/i386/useldt.h index 067e5e242..02326729a 100644 --- a/libpthread/linuxthreads/sysdeps/i386/useldt.h +++ b/libpthread/linuxthreads/sysdeps/i386/useldt.h @@ -21,7 +21,6 @@ #ifndef __ASSEMBLER__ #include <stddef.h> /* For offsetof. */ #include <stdlib.h> /* For abort(). */ -#include <sysdep.h> /* We don't want to include the kernel header. So duplicate the @@ -76,7 +75,7 @@ extern int __modify_ldt (int, struct modify_ldt_ldt_s *, size_t); #ifdef __PIC__ # define USETLS_EBX_ARG "r" -# define USETLS_LOAD_EBX "xchgl %1, %%ebx\n\t" +# define USETLS_LOAD_EBX "xchgl %3, %%ebx\n\t" #else # define USETLS_EBX_ARG "b" # define USETLS_LOAD_EBX @@ -86,7 +85,7 @@ extern int __modify_ldt (int, struct modify_ldt_ldt_s *, size_t); because we inherited the value set up in the main thread by TLS setup. We need to extract that value and set up the same segment in this thread. */ -#ifdef __UCLIBC_HAS_TLS__ +#if USE_TLS # define DO_SET_THREAD_AREA_REUSE(nr) 1 #else /* Without TLS, we do the initialization of the main thread, where NR == 0. */ @@ -108,10 +107,8 @@ extern int __modify_ldt (int, struct modify_ldt_ldt_s *, size_t); "movl %2, %%eax\n\t" \ "int $0x80\n\t" \ USETLS_LOAD_EBX \ - : "=&a" (__result) \ - : USETLS_EBX_ARG (&ldt_entry), "i" (__NR_set_thread_area), \ - "m" (ldt_entry) \ - : "memory"); \ + : "&a" (__result) \ + : USETLS_EBX_ARG (&ldt_entry), "i" (__NR_set_thread_area)); \ if (__result == 0) \ __asm__ ("movw %w0, %%gs" :: "q" (__gs)); \ else \ @@ -128,10 +125,8 @@ extern int __modify_ldt (int, struct modify_ldt_ldt_s *, size_t); "movl %2, %%eax\n\t" \ "int $0x80\n\t" \ USETLS_LOAD_EBX \ - : "=&a" (__result) \ - : USETLS_EBX_ARG (&ldt_entry), "i" (__NR_set_thread_area), \ - "m" (ldt_entry) \ - : "memory"); \ + : "&a" (__result) \ + : USETLS_EBX_ARG (&ldt_entry), "i" (__NR_set_thread_area)); \ if (__result == 0) \ { \ __gs = (ldt_entry.entry_number << 3) + 3; \ @@ -304,10 +299,8 @@ extern int __have_no_set_thread_area; }) #endif -#if __ASSUME_LDT_WORKS > 0 /* We want the OS to assign stack addresses. */ #define FLOATING_STACKS 1 /* Maximum size of the stack if the rlimit is unlimited. */ #define ARCH_STACK_MAX_SIZE 8*1024*1024 -#endif |