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/* Copyright (C) 2002, 2003 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>
.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
/* For the calculation see asm/vsyscall.h. */
#define VSYSCALL_ADDR_vgettimeofday 0xffffffffff600000
.globl __lll_mutex_lock_wait
.type __lll_mutex_lock_wait,@function
.hidden __lll_mutex_lock_wait
.align 16
__lll_mutex_lock_wait:
pushq %r10
pushq %rdx
xorq %r10, %r10 /* No timeout. */
1:
leaq 1(%rsi), %rdx /* account for the preceeded xadd. */
movq %r10, %rsi /* movq $FUTEX_WAIT, %rsi */
movq $SYS_futex, %rax
syscall
movl $1, %esi
LOCK
xaddl %esi, (%rdi)
testl %esi, %esi
jne 1b
movl $2, (%rdi)
popq %rdx
popq %r10
retq
.size __lll_mutex_lock_wait,.-__lll_mutex_lock_wait
#ifdef NOT_IN_libc
.globl __lll_mutex_timedlock_wait
.type __lll_mutex_timedlock_wait,@function
.hidden __lll_mutex_timedlock_wait
.align 16
__lll_mutex_timedlock_wait:
/* Check for a valid timeout value. */
cmpq $1000000000, 8(%rdx)
jae 3f
pushq %r12
pushq %r13
pushq %r14
/* Stack frame for the timespec and timeval structs. */
subq $16, %rsp
movq %rdi, %r12
movq %rdx, %r13
1: leaq 1(%rax), %r14
/* Get current time. */
movq %rsp, %rdi
xorq %rsi, %rsi
movq $VSYSCALL_ADDR_vgettimeofday, %rax
/* This is a regular function call, all calleer-save registers
might be clobbered. */
callq *%rax
/* Compute relative timeout. */
movq 8(%rsp), %rax
movq $1000, %rdi
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 5f /* Time is already up. */
/* Futex call. */
movq %rdi, (%rsp) /* Store relative timeout. */
movq %rsi, 8(%rsp)
movl %r14d, %edx
movq %rsp, %r10
xorq %rsi, %rsi /* movq $FUTEX_WAIT, %rsi */
movq %r12, %rdi
movq $SYS_futex, %rax
syscall
movq %rax, %rcx
movl $1, %eax
LOCK
xaddl %eax, (%rdi)
testl %eax, %eax
jne 7f
movl $2, (%rdi)
xorl %eax, %eax
8: addq $16, %rsp
popq %r14
popq %r13
popq %r12
retq
/* Check whether the time expired. */
7: cmpq $-ETIMEDOUT, %rcx
je 5f
jmp 1b
3: movl $EINVAL, %eax
retq
5: movl $ETIMEDOUT, %eax
jmp 8b
.size __lll_mutex_timedlock_wait,.-__lll_mutex_timedlock_wait
#endif
.globl __lll_mutex_unlock_wake
.type __lll_mutex_unlock_wake,@function
.hidden __lll_mutex_unlock_wake
.align 16
__lll_mutex_unlock_wake:
pushq %rsi
pushq %rdx
movl $0, (%rdi)
movq $FUTEX_WAKE, %rsi
movl $1, %edx /* Wake one thread. */
movq $SYS_futex, %rax
syscall
popq %rdx
popq %rsi
retq
.size __lll_mutex_unlock_wake,.-__lll_mutex_unlock_wake
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