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/* Copyright (C) 2002-2017 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, see
<http://www.gnu.org/licenses/>. */
#include <sysdep.h>
#include <pthread-errnos.h>
#include <lowlevellock.h>
#include <lowlevelrobustlock.h>
#include <kernel-features.h>
.text
#define FUTEX_WAITERS 0x80000000
#define FUTEX_OWNER_DIED 0x40000000
#ifdef __ASSUME_PRIVATE_FUTEX
# define LOAD_FUTEX_WAIT(reg) \
xorl $(FUTEX_WAIT | FUTEX_PRIVATE_FLAG), reg
#else
# if FUTEX_WAIT == 0
# define LOAD_FUTEX_WAIT(reg) \
xorl $FUTEX_PRIVATE_FLAG, reg ; \
andl %gs:PRIVATE_FUTEX, reg
# else
# define LOAD_FUTEX_WAIT(reg) \
xorl $FUTEX_PRIVATE_FLAG, reg ; \
andl %gs:PRIVATE_FUTEX, reg ; \
orl $FUTEX_WAIT, reg
# endif
#endif
.globl __lll_robust_lock_wait
.type __lll_robust_lock_wait,@function
.hidden __lll_robust_lock_wait
.align 16
__lll_robust_lock_wait:
cfi_startproc
pushl %edx
cfi_adjust_cfa_offset(4)
pushl %ebx
cfi_adjust_cfa_offset(4)
pushl %esi
cfi_adjust_cfa_offset(4)
cfi_offset(%edx, -8)
cfi_offset(%ebx, -12)
cfi_offset(%esi, -16)
movl %edx, %ebx
xorl %esi, %esi /* No timeout. */
LOAD_FUTEX_WAIT (%ecx)
4: movl %eax, %edx
orl $FUTEX_WAITERS, %edx
testl $FUTEX_OWNER_DIED, %eax
jnz 3f
cmpl %edx, %eax /* NB: %edx == 2 */
je 1f
LOCK
cmpxchgl %edx, (%ebx)
jnz 2f
1: movl $SYS_futex, %eax
ENTER_KERNEL
movl (%ebx), %eax
2: test %eax, %eax
jne 4b
movl %gs:TID, %edx
orl $FUTEX_WAITERS, %edx
LOCK
cmpxchgl %edx, (%ebx)
jnz 4b
/* NB: %eax == 0 */
3: popl %esi
cfi_adjust_cfa_offset(-4)
cfi_restore(%esi)
popl %ebx
cfi_adjust_cfa_offset(-4)
cfi_restore(%ebx)
popl %edx
cfi_adjust_cfa_offset(-4)
cfi_restore(%edx)
ret
cfi_endproc
.size __lll_robust_lock_wait,.-__lll_robust_lock_wait
.globl __lll_robust_timedlock_wait
.type __lll_robust_timedlock_wait,@function
.hidden __lll_robust_timedlock_wait
.align 16
__lll_robust_timedlock_wait:
cfi_startproc
/* Check for a valid timeout value. */
cmpl $1000000000, 4(%edx)
jae 3f
pushl %edi
cfi_adjust_cfa_offset(4)
pushl %esi
cfi_adjust_cfa_offset(4)
pushl %ebx
cfi_adjust_cfa_offset(4)
pushl %ebp
cfi_adjust_cfa_offset(4)
cfi_offset(%edi, -8)
cfi_offset(%esi, -12)
cfi_offset(%ebx, -16)
cfi_offset(%ebp, -20)
/* Stack frame for the timespec and timeval structs. */
subl $12, %esp
cfi_adjust_cfa_offset(12)
movl %ecx, %ebp
movl %edx, %edi
1: movl %eax, 8(%esp)
/* Get current time. */
movl %esp, %ebx
xorl %ecx, %ecx
movl $__NR_gettimeofday, %eax
ENTER_KERNEL
/* Compute relative timeout. */
movl 4(%esp), %eax
movl $1000, %edx
mul %edx /* Milli seconds to nano seconds. */
movl (%edi), %ecx
movl 4(%edi), %edx
subl (%esp), %ecx
subl %eax, %edx
jns 4f
addl $1000000000, %edx
subl $1, %ecx
4: testl %ecx, %ecx
js 8f /* Time is already up. */
/* Store relative timeout. */
movl %ecx, (%esp)
movl %edx, 4(%esp)
movl %ebp, %ebx
movl 8(%esp), %edx
movl %edx, %eax
orl $FUTEX_WAITERS, %edx
testl $FUTEX_OWNER_DIED, %eax
jnz 6f
cmpl %eax, %edx
je 2f
LOCK
cmpxchgl %edx, (%ebx)
movl $0, %ecx /* Must use mov to avoid changing cc. */
jnz 5f
2:
/* Futex call. */
movl %esp, %esi
movl 20(%esp), %ecx
LOAD_FUTEX_WAIT (%ecx)
movl $SYS_futex, %eax
ENTER_KERNEL
movl %eax, %ecx
movl (%ebx), %eax
5: testl %eax, %eax
jne 7f
movl %gs:TID, %edx
orl $FUTEX_WAITERS, %edx
LOCK
cmpxchgl %edx, (%ebx)
jnz 7f
6: addl $12, %esp
cfi_adjust_cfa_offset(-12)
popl %ebp
cfi_adjust_cfa_offset(-4)
cfi_restore(%ebp)
popl %ebx
cfi_adjust_cfa_offset(-4)
cfi_restore(%ebx)
popl %esi
cfi_adjust_cfa_offset(-4)
cfi_restore(%esi)
popl %edi
cfi_adjust_cfa_offset(-4)
cfi_restore(%edi)
ret
3: movl $EINVAL, %eax
ret
cfi_adjust_cfa_offset(28)
cfi_offset(%edi, -8)
cfi_offset(%esi, -12)
cfi_offset(%ebx, -16)
cfi_offset(%ebp, -20)
/* Check whether the time expired. */
7: cmpl $-ETIMEDOUT, %ecx
jne 1b
8: movl $ETIMEDOUT, %eax
jmp 6b
cfi_endproc
.size __lll_robust_timedlock_wait,.-__lll_robust_timedlock_wait
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