mirror of
https://sourceware.org/git/glibc.git
synced 2024-12-18 08:51:06 +00:00
342 lines
12 KiB
C
342 lines
12 KiB
C
/* 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 */
|