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Diffstat (limited to 'libpthread/nptl/sysdeps/unix/sysv/linux/x86_64/lowlevellock.h')
| -rw-r--r-- | libpthread/nptl/sysdeps/unix/sysv/linux/x86_64/lowlevellock.h | 341 |
1 files changed, 341 insertions, 0 deletions
diff --git a/libpthread/nptl/sysdeps/unix/sysv/linux/x86_64/lowlevellock.h b/libpthread/nptl/sysdeps/unix/sysv/linux/x86_64/lowlevellock.h new file mode 100644 index 000000000..40c2518af --- /dev/null +++ b/libpthread/nptl/sysdeps/unix/sysv/linux/x86_64/lowlevellock.h @@ -0,0 +1,341 @@ +/* Copyright (C) 2002, 2003, 2004 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Ulrich Drepper <drepper@redhat.com>, 2002. + + 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; if not, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +#ifndef _LOWLEVELLOCK_H +#define _LOWLEVELLOCK_H 1 + +#include <time.h> +#include <sys/param.h> +#include <bits/pthreadtypes.h> + +#ifndef LOCK_INSTR +# ifdef UP +# define LOCK_INSTR /* nothing */ +# else +# define LOCK_INSTR "lock;" +# endif +#endif + +#define SYS_futex 202 +#define FUTEX_WAIT 0 +#define FUTEX_WAKE 1 + + +/* Initializer for compatibility lock. */ +#define LLL_MUTEX_LOCK_INITIALIZER (0) +#define LLL_MUTEX_LOCK_INITIALIZER_LOCKED (1) +#define LLL_MUTEX_LOCK_INITIALIZER_WAITERS (2) + +/* Delay in spinlock loop. */ +#define BUSY_WAIT_NOP asm ("rep; nop") + + +#define lll_futex_wait(futex, val) \ + do { \ + int __ignore; \ + register __typeof (val) _val asm ("edx") = (val); \ + __asm __volatile ("xorq %%r10, %%r10\n\t" \ + "syscall" \ + : "=a" (__ignore) \ + : "0" (SYS_futex), "D" (futex), "S" (FUTEX_WAIT), \ + "d" (_val) \ + : "memory", "cc", "r10", "r11", "cx"); \ + } while (0) + + +#define lll_futex_wake(futex, nr) \ + do { \ + int __ignore; \ + register __typeof (nr) _nr asm ("edx") = (nr); \ + __asm __volatile ("syscall" \ + : "=a" (__ignore) \ + : "0" (SYS_futex), "D" (futex), "S" (FUTEX_WAKE), \ + "d" (_nr) \ + : "memory", "cc", "r10", "r11", "cx"); \ + } while (0) + + +/* Does not preserve %eax and %ecx. */ +extern int __lll_mutex_lock_wait (int *__futex, int __val) attribute_hidden; +/* Does not preserver %eax, %ecx, and %edx. */ +extern int __lll_mutex_timedlock_wait (int *__futex, int __val, + const struct timespec *__abstime) + attribute_hidden; +/* Preserves all registers but %eax. */ +extern int __lll_mutex_unlock_wait (int *__futex) attribute_hidden; + + +/* NB: in the lll_mutex_trylock macro we simply return the value in %eax + after the cmpxchg instruction. In case the operation succeded this + value is zero. In case the operation failed, the cmpxchg instruction + has loaded the current value of the memory work which is guaranteed + to be nonzero. */ +#define lll_mutex_trylock(futex) \ + ({ int ret; \ + __asm __volatile (LOCK_INSTR "cmpxchgl %2, %1" \ + : "=a" (ret), "=m" (futex) \ + : "r" (LLL_MUTEX_LOCK_INITIALIZER_LOCKED), "m" (futex),\ + "0" (LLL_MUTEX_LOCK_INITIALIZER) \ + : "memory"); \ + ret; }) + + +#define lll_mutex_cond_trylock(futex) \ + ({ int ret; \ + __asm __volatile (LOCK_INSTR "cmpxchgl %2, %1" \ + : "=a" (ret), "=m" (futex) \ + : "r" (LLL_MUTEX_LOCK_INITIALIZER_WAITERS), \ + "m" (futex), "0" (LLL_MUTEX_LOCK_INITIALIZER) \ + : "memory"); \ + ret; }) + + +#define lll_mutex_lock(futex) \ + (void) ({ int ignore1, ignore2, ignore3; \ + __asm __volatile (LOCK_INSTR "cmpxchgl %0, %2\n\t" \ + "jnz 1f\n\t" \ + ".subsection 1\n" \ + "1:\tleaq %2, %%rdi\n\t" \ + "subq $128, %%rsp\n\t" \ + "callq __lll_mutex_lock_wait\n\t" \ + "addq $128, %%rsp\n\t" \ + "jmp 2f\n\t" \ + ".previous\n" \ + "2:" \ + : "=S" (ignore1), "=&D" (ignore2), "=m" (futex),\ + "=a" (ignore3) \ + : "0" (1), "m" (futex), "3" (0) \ + : "cx", "r11", "cc", "memory"); }) + + +#define lll_mutex_cond_lock(futex) \ + (void) ({ int ignore1, ignore2, ignore3; \ + __asm __volatile (LOCK_INSTR "cmpxchgl %0, %2\n\t" \ + "jnz 1f\n\t" \ + ".subsection 1\n" \ + "1:\tleaq %2, %%rdi\n\t" \ + "subq $128, %%rsp\n\t" \ + "callq __lll_mutex_lock_wait\n\t" \ + "addq $128, %%rsp\n\t" \ + "jmp 2f\n\t" \ + ".previous\n" \ + "2:" \ + : "=S" (ignore1), "=&D" (ignore2), "=m" (futex),\ + "=a" (ignore3) \ + : "0" (2), "m" (futex), "3" (0) \ + : "cx", "r11", "cc", "memory"); }) + + +#define lll_mutex_timedlock(futex, timeout) \ + ({ int result, ignore1, ignore2, ignore3; \ + __asm __volatile (LOCK_INSTR "cmpxchgl %2, %4\n\t" \ + "jnz 1f\n\t" \ + ".subsection 1\n" \ + "1:\tleaq %4, %%rdi\n\t" \ + "movq %8, %%rdx\n\t" \ + "subq $128, %%rsp\n\t" \ + "callq __lll_mutex_timedlock_wait\n\t" \ + "addq $128, %%rsp\n\t" \ + "jmp 2f\n\t" \ + ".previous\n" \ + "2:" \ + : "=a" (result), "=&D" (ignore1), "=S" (ignore2), \ + "=&d" (ignore3), "=m" (futex) \ + : "0" (0), "2" (1), "m" (futex), "m" (timeout) \ + : "memory", "cx", "cc", "r10", "r11"); \ + result; }) + + +#define lll_mutex_unlock(futex) \ + (void) ({ int ignore; \ + __asm __volatile (LOCK_INSTR "decl %0\n\t" \ + "jne 1f\n\t" \ + ".subsection 1\n" \ + "1:\tleaq %0, %%rdi\n\t" \ + "subq $128, %%rsp\n\t" \ + "callq __lll_mutex_unlock_wake\n\t" \ + "addq $128, %%rsp\n\t" \ + "jmp 2f\n\t" \ + ".previous\n" \ + "2:" \ + : "=m" (futex), "=&D" (ignore) \ + : "m" (futex) \ + : "ax", "cx", "r11", "cc", "memory"); }) + + +#define lll_mutex_islocked(futex) \ + (futex != LLL_MUTEX_LOCK_INITIALIZER) + + +/* We have a separate internal lock implementation which is not tied + to binary compatibility. */ + +/* Type for lock object. */ +typedef int lll_lock_t; + +/* Initializers for lock. */ +#define LLL_LOCK_INITIALIZER (0) +#define LLL_LOCK_INITIALIZER_LOCKED (1) + + +extern int lll_unlock_wake_cb (int *__futex) attribute_hidden; + + +/* The states of a lock are: + 0 - untaken + 1 - taken by one user + 2 - taken by more users */ + + +#if defined NOT_IN_libc || defined UP +# define lll_trylock(futex) lll_mutex_trylock (futex) +# define lll_lock(futex) lll_mutex_lock (futex) +# define lll_unlock(futex) lll_mutex_unlock (futex) +#else +/* Special versions of the macros for use in libc itself. They avoid + the lock prefix when the thread library is not used. + + The code sequence to avoid unnecessary lock prefixes is what the AMD + guys suggested. If you do not like it, bring it up with AMD. + + XXX In future we might even want to avoid it on UP machines. */ + +# define lll_trylock(futex) \ + ({ unsigned char ret; \ + __asm __volatile ("cmpl $0, __libc_multiple_threads(%%rip)\n\t" \ + "je 0f\n\t" \ + "lock; cmpxchgl %2, %1\n\t" \ + "jmp 1f\n" \ + "0:\tcmpxchgl %2, %1\n\t" \ + "1:setne %0" \ + : "=a" (ret), "=m" (futex) \ + : "r" (LLL_MUTEX_LOCK_INITIALIZER_LOCKED), "m" (futex),\ + "0" (LLL_MUTEX_LOCK_INITIALIZER) \ + : "memory"); \ + ret; }) + + +# define lll_lock(futex) \ + (void) ({ int ignore1, ignore2, ignore3; \ + __asm __volatile ("cmpl $0, __libc_multiple_threads(%%rip)\n\t" \ + "je 0f\n\t" \ + "lock; cmpxchgl %0, %2\n\t" \ + "jnz 1f\n\t" \ + "jmp 2f\n" \ + "0:\tcmpxchgl %0, %2\n\t" \ + "jnz 1f\n\t" \ + ".subsection 1\n" \ + "1:\tleaq %2, %%rdi\n\t" \ + "subq $128, %%rsp\n\t" \ + "callq __lll_mutex_lock_wait\n\t" \ + "addq $128, %%rsp\n\t" \ + "jmp 2f\n\t" \ + ".previous\n" \ + "2:" \ + : "=S" (ignore1), "=&D" (ignore2), "=m" (futex),\ + "=a" (ignore3) \ + : "0" (1), "m" (futex), "3" (0) \ + : "cx", "r11", "cc", "memory"); }) + + +# define lll_unlock(futex) \ + (void) ({ int ignore; \ + __asm __volatile ("cmpl $0, __libc_multiple_threads(%%rip)\n\t" \ + "je 0f\n\t" \ + "lock; decl %0\n\t" \ + "jne 1f\n\t" \ + "jmp 2f\n" \ + "0:\tdecl %0\n\t" \ + "jne 1f\n\t" \ + ".subsection 1\n" \ + "1:\tleaq %0, %%rdi\n\t" \ + "subq $128, %%rsp\n\t" \ + "callq __lll_mutex_unlock_wake\n\t" \ + "addq $128, %%rsp\n\t" \ + "jmp 2f\n\t" \ + ".previous\n" \ + "2:" \ + : "=m" (futex), "=&D" (ignore) \ + : "m" (futex) \ + : "ax", "cx", "r11", "cc", "memory"); }) +#endif + + +#define lll_islocked(futex) \ + (futex != LLL_MUTEX_LOCK_INITIALIZER) + + +/* The kernel notifies a process with uses CLONE_CLEARTID via futex + wakeup when the clone terminates. The memory location contains the + thread ID while the clone is running and is reset to zero + afterwards. + + The macro parameter must not have any side effect. */ +#define lll_wait_tid(tid) \ + do { \ + int __ignore; \ + register __typeof (tid) _tid asm ("edx") = (tid); \ + if (_tid != 0) \ + __asm __volatile ("xorq %%r10, %%r10\n\t" \ + "1:\tmovq %2, %%rax\n\t" \ + "syscall\n\t" \ + "cmpl $0, (%%rdi)\n\t" \ + "jne 1b" \ + : "=&a" (__ignore) \ + : "S" (FUTEX_WAIT), "i" (SYS_futex), "D" (&tid), \ + "d" (_tid) \ + : "memory", "cc", "r10", "r11", "cx"); \ + } while (0) + +extern int __lll_timedwait_tid (int *tid, const struct timespec *abstime) + attribute_hidden; +#define lll_timedwait_tid(tid, abstime) \ + ({ \ + int __result = 0; \ + if (tid != 0) \ + { \ + if (abstime->tv_nsec < 0 || abstime->tv_nsec >= 1000000000) \ + __result = EINVAL; \ + else \ + __result = __lll_timedwait_tid (&tid, abstime); \ + } \ + __result; }) + + +/* Conditional variable handling. */ + +extern void __lll_cond_wait (pthread_cond_t *cond) attribute_hidden; +extern int __lll_cond_timedwait (pthread_cond_t *cond, + const struct timespec *abstime) + attribute_hidden; +extern void __lll_cond_wake (pthread_cond_t *cond) attribute_hidden; +extern void __lll_cond_broadcast (pthread_cond_t *cond) attribute_hidden; + + +#define lll_cond_wait(cond) \ + __lll_cond_wait (cond) +#define lll_cond_timedwait(cond, abstime) \ + __lll_cond_timedwait (cond, abstime) +#define lll_cond_wake(cond) \ + __lll_cond_wake (cond) +#define lll_cond_broadcast(cond) \ + __lll_cond_broadcast (cond) + + +#endif /* lowlevellock.h */ |