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/* Copyright (C) 2002-2006, 2007 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
#ifndef FUTEX_WAIT
# define FUTEX_WAIT 0
# define FUTEX_WAKE 1
#endif
#ifndef LOAD_FUTEX_WAIT
# if FUTEX_WAIT == 0
# define LOAD_FUTEX_WAIT(reg) \
xorl reg, reg
# else
# define LOAD_FUTEX_WAIT(reg) \
movl $FUTEX_WAIT, reg
# endif
# define LOAD_FUTEX_WAKE(reg) \
movl $FUTEX_WAKE, reg
#endif
/* 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:
cfi_startproc
pushq %r10
cfi_adjust_cfa_offset(8)
pushq %rdx
cfi_adjust_cfa_offset(8)
cfi_offset(%r10, -16)
cfi_offset(%rdx, -24)
xorq %r10, %r10 /* No timeout. */
movl $2, %edx
LOAD_FUTEX_WAIT (%esi)
cmpl %edx, %eax /* NB: %edx == 2 */
jne 2f
1: movl $SYS_futex, %eax
syscall
2: movl %edx, %eax
xchgl %eax, (%rdi) /* NB: lock is implied */
testl %eax, %eax
jnz 1b
popq %rdx
cfi_adjust_cfa_offset(-8)
cfi_restore(%rdx)
popq %r10
cfi_adjust_cfa_offset(-8)
cfi_restore(%r10)
retq
cfi_endproc
.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:
cfi_startproc
/* Check for a valid timeout value. */
cmpq $1000000000, 8(%rdx)
jae 3f
pushq %r8
cfi_adjust_cfa_offset(8)
pushq %r9
cfi_adjust_cfa_offset(8)
pushq %r12
cfi_adjust_cfa_offset(8)
pushq %r13
cfi_adjust_cfa_offset(8)
pushq %r14
cfi_adjust_cfa_offset(8)
cfi_offset(%r8, -16)
cfi_offset(%r9, -24)
cfi_offset(%r12, -32)
cfi_offset(%r13, -40)
cfi_offset(%r14, -48)
/* Stack frame for the timespec and timeval structs. */
subq $16, %rsp
cfi_adjust_cfa_offset(16)
movq %rdi, %r12
movq %rdx, %r13
1:
/* 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 5f /* Time is already up. */
/* Futex call. */
movq %rdi, (%rsp) /* Store relative timeout. */
movq %rsi, 8(%rsp)
movl $1, %eax
movl $2, %edx
LOCK
cmpxchgl %edx, (%r12)
testl %eax, %eax
je 8f
movq %rsp, %r10
LOAD_FUTEX_WAIT (%esi)
movq %r12, %rdi
movl $SYS_futex, %eax
syscall
movq %rax, %rcx
8: /* NB: %edx == 2 */
xorl %eax, %eax
LOCK
cmpxchgl %edx, (%r12)
jnz 7f
6: addq $16, %rsp
cfi_adjust_cfa_offset(-16)
popq %r14
cfi_adjust_cfa_offset(-8)
cfi_restore(%r14)
popq %r13
cfi_adjust_cfa_offset(-8)
cfi_restore(%r13)
popq %r12
cfi_adjust_cfa_offset(-8)
cfi_restore(%r12)
popq %r9
cfi_adjust_cfa_offset(-8)
cfi_restore(%r9)
popq %r8
cfi_adjust_cfa_offset(-8)
cfi_restore(%r8)
retq
3: movl $EINVAL, %eax
retq
cfi_adjust_cfa_offset(56)
cfi_offset(%r8, -16)
cfi_offset(%r9, -24)
cfi_offset(%r12, -32)
cfi_offset(%r13, -40)
cfi_offset(%r14, -48)
/* Check whether the time expired. */
7: cmpq $-ETIMEDOUT, %rcx
je 5f
/* Make sure the current holder knows we are going to sleep. */
movl %edx, %eax
xchgl %eax, (%rdi)
testl %eax, %eax
jz 6b
jmp 1b
5: movl $ETIMEDOUT, %eax
jmp 6b
cfi_endproc
.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:
cfi_startproc
pushq %rsi
cfi_adjust_cfa_offset(8)
pushq %rdx
cfi_adjust_cfa_offset(8)
cfi_offset(%rsi, -16)
cfi_offset(%rdx, -24)
movl $0, (%rdi)
LOAD_FUTEX_WAKE (%esi)
movl $1, %edx /* Wake one thread. */
movl $SYS_futex, %eax
syscall
popq %rdx
cfi_adjust_cfa_offset(-8)
cfi_restore(%rdx)
popq %rsi
cfi_adjust_cfa_offset(-8)
cfi_restore(%rsi)
retq
cfi_endproc
.size __lll_mutex_unlock_wake,.-__lll_mutex_unlock_wake
#ifdef NOT_IN_libc
.globl __lll_timedwait_tid
.type __lll_timedwait_tid,@function
.hidden __lll_timedwait_tid
.align 16
__lll_timedwait_tid:
cfi_startproc
pushq %r12
cfi_adjust_cfa_offset(8)
pushq %r13
cfi_adjust_cfa_offset(8)
cfi_offset(%r12, -16)
cfi_offset(%r13, -24)
movq %rdi, %r12
movq %rsi, %r13
subq $16, %rsp
cfi_adjust_cfa_offset(16)
/* Get current time. */
2: movq %rsp, %rdi
xorl %esi, %esi
movq $VSYSCALL_ADDR_vgettimeofday, %rax
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 5f
addq $1000000000, %rsi
decq %rdi
5: testq %rdi, %rdi
js 6f /* Time is already up. */
movq %rdi, (%rsp) /* Store relative timeout. */
movq %rsi, 8(%rsp)
movl (%r12), %edx
testl %edx, %edx
jz 4f
movq %rsp, %r10
/* XXX The kernel so far uses global futex for the wakeup at
all times. */
#if FUTEX_WAIT == 0
xorl %esi, %esi
#else
movl $FUTEX_WAIT, %esi
#endif
movq %r12, %rdi
movl $SYS_futex, %eax
syscall
cmpl $0, (%rdi)
jne 1f
4: xorl %eax, %eax
8: addq $16, %rsp
cfi_adjust_cfa_offset(-16)
popq %r13
cfi_adjust_cfa_offset(-8)
cfi_restore(%r13)
popq %r12
cfi_adjust_cfa_offset(-8)
cfi_restore(%r12)
retq
cfi_adjust_cfa_offset(32)
1: cmpq $-ETIMEDOUT, %rax
jne 2b
6: movl $ETIMEDOUT, %eax
jmp 8b
cfi_endproc
.size __lll_timedwait_tid,.-__lll_timedwait_tid
#endif
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