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/* Copyright (C) 2002, 2003, 2004, 2005, 2006 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. */
#include <sysdep.h>
#include <pthread-errnos.h>
#include <lowlevelrobustlock.h>
.text
#ifndef LOCK
# ifdef UP
# define LOCK
# else
# define LOCK lock
# endif
#endif
#define SYS_futex 202
#define FUTEX_WAIT 0
#define FUTEX_WAKE 1
#define FUTEX_WAITERS 0x80000000
#define FUTEX_OWNER_DIED 0x40000000
/* For the calculation see asm/vsyscall.h. */
#define VSYSCALL_ADDR_vgettimeofday 0xffffffffff600000
.globl __lll_robust_mutex_lock_wait
.type __lll_robust_mutex_lock_wait,@function
.hidden __lll_robust_mutex_lock_wait
.align 16
__lll_robust_mutex_lock_wait:
pushq %r10
pushq %rdx
xorq %r10, %r10 /* No timeout. */
#if FUTEX_WAIT == 0
xorl %esi, %esi
#else
movl $FUTEX_WAIT, %esi
#endif
4: movl %eax, %edx
orl $FUTEX_WAITERS, %edx
testl $FUTEX_OWNER_DIED, %eax
jnz 3f
cmpl %edx, %eax
je 1f
LOCK
cmpxchgl %edx, (%rdi)
jnz 2f
1: movl $SYS_futex, %eax
syscall
movl (%rdi), %eax
2: testl %eax, %eax
jne 4b
movl %fs:TID, %edx
orl $FUTEX_WAITERS, %edx
LOCK
cmpxchgl %edx, (%rdi)
jnz 4b
/* NB: %rax == 0 */
3: popq %rdx
popq %r10
retq
.size __lll_robust_mutex_lock_wait,.-__lll_robust_mutex_lock_wait
.globl __lll_robust_mutex_timedlock_wait
.type __lll_robust_mutex_timedlock_wait,@function
.hidden __lll_robust_mutex_timedlock_wait
.align 16
__lll_robust_mutex_timedlock_wait:
/* Check for a valid timeout value. */
cmpq $1000000000, 8(%rdx)
jae 3f
pushq %r8
pushq %r9
pushq %r12
pushq %r13
/* Stack frame for the timespec and timeval structs. */
subq $24, %rsp
movq %rdi, %r12
movq %rdx, %r13
1: movq %rax, 16(%rsp)
/* Get current time. */
movq %rsp, %rdi
xorl %esi, %esi
movq $VSYSCALL_ADDR_vgettimeofday, %rax
/* This is a regular function call, all caller-save registers
might be clobbered. */
callq *%rax
/* Compute relative timeout. */
movq 8(%rsp), %rax
movl $1000, %edi
mul %rdi /* Milli seconds to nano seconds. */
movq (%r13), %rdi
movq 8(%r13), %rsi
subq (%rsp), %rdi
subq %rax, %rsi
jns 4f
addq $1000000000, %rsi
decq %rdi
4: testq %rdi, %rdi
js 8f /* Time is already up. */
/* Futex call. */
movq %rdi, (%rsp) /* Store relative timeout. */
movq %rsi, 8(%rsp)
movq 16(%rsp), %rdx
movl %edx, %eax
orl $FUTEX_WAITERS, %edx
testl $FUTEX_OWNER_DIED, %eax
jnz 6f
cmpl %eax, %edx
je 2f
LOCK
cmpxchgl %edx, (%r12)
movq $0, %rcx /* Must use mov to avoid changing cc. */
jnz 5f
2: movq %rsp, %r10
#if FUTEX_WAIT == 0
xorl %esi, %esi
#else
movl $FUTEX_WAIT, %esi
#endif
movq %r12, %rdi
movl $SYS_futex, %eax
syscall
movq %rax, %rcx
movl (%r12), %eax
5: testl %eax, %eax
jne 7f
movl %fs:TID, %edx
orl $FUTEX_WAITERS, %edx
LOCK
cmpxchgl %edx, (%r12)
jnz 7f
6: addq $24, %rsp
popq %r13
popq %r12
popq %r9
popq %r8
retq
/* Check whether the time expired. */
7: cmpq $-ETIMEDOUT, %rcx
jne 1b
8: movl $ETIMEDOUT, %eax
jmp 6b
3: movl $EINVAL, %eax
retq
.size __lll_robust_mutex_timedlock_wait,.-__lll_robust_mutex_timedlock_wait
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