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/* Copyright (C) 2002-2014 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
# define LOAD_FUTEX_WAIT_ABS(reg) \
xorl $(FUTEX_WAIT_BITSET | FUTEX_PRIVATE_FLAG | FUTEX_CLOCK_REALTIME), reg
#else
# if FUTEX_WAIT == 0
# define LOAD_FUTEX_WAIT(reg) \
xorl $FUTEX_PRIVATE_FLAG, reg ; \
andl %fs:PRIVATE_FUTEX, reg
# else
# define LOAD_FUTEX_WAIT(reg) \
xorl $FUTEX_PRIVATE_FLAG, reg ; \
andl %fs:PRIVATE_FUTEX, reg ; \
orl $FUTEX_WAIT, reg
# endif
# define LOAD_FUTEX_WAIT_ABS(reg) \
xorl $FUTEX_PRIVATE_FLAG, reg ; \
andl %fs:PRIVATE_FUTEX, reg ; \
orl $FUTEX_WAIT_BITSET | FUTEX_CLOCK_REALTIME, reg
#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
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. */
LOAD_FUTEX_WAIT (%esi)
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
cfi_adjust_cfa_offset(-8)
cfi_restore(%rdx)
popq %r10
cfi_adjust_cfa_offset(-8)
cfi_restore(%r10)
retq
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
# ifndef __ASSUME_FUTEX_CLOCK_REALTIME
# ifdef PIC
cmpl $0, __have_futex_clock_realtime(%rip)
# else
cmpl $0, __have_futex_clock_realtime
# endif
je .Lreltmo
# endif
cmpq $0, (%rdx)
js 7f
pushq %r9
cfi_adjust_cfa_offset(8)
cfi_rel_offset(%r9, 0)
movq %rdx, %r10
movl $0xffffffff, %r9d
LOAD_FUTEX_WAIT_ABS (%esi)
1: testl $FUTEX_OWNER_DIED, %eax
jnz 3f
movl %eax, %edx
orl $FUTEX_WAITERS, %edx
cmpl %eax, %edx
je 5f
LOCK
cmpxchgl %edx, (%rdi)
movq $0, %rcx /* Must use mov to avoid changing cc. */
jnz 6f
5: movl $SYS_futex, %eax
syscall
movl %eax, %ecx
movl (%rdi), %eax
6: testl %eax, %eax
jne 2f
movl %fs:TID, %edx
orl $FUTEX_WAITERS, %edx
LOCK
cmpxchgl %edx, (%rdi)
jnz 2f
3: popq %r9
cfi_adjust_cfa_offset(-8)
cfi_restore(%r9)
retq
cfi_adjust_cfa_offset(8)
cfi_rel_offset(%r9, 0)
/* Check whether the time expired. */
2: cmpl $-ETIMEDOUT, %ecx
je 4f
cmpl $-EINVAL, %ecx
jne 1b
4: movl %ecx, %eax
negl %eax
jmp 3b
cfi_adjust_cfa_offset(-8)
cfi_restore(%r9)
7: movl $ETIMEDOUT, %eax
retq
# ifndef __ASSUME_FUTEX_CLOCK_REALTIME
.Lreltmo:
/* 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)
cfi_offset(%r8, -16)
cfi_offset(%r9, -24)
cfi_offset(%r12, -32)
cfi_offset(%r13, -40)
pushq %rsi
cfi_adjust_cfa_offset(8)
/* Stack frame for the timespec and timeval structs. */
subq $32, %rsp
cfi_adjust_cfa_offset(32)
movq %rdi, %r12
movq %rdx, %r13
1: movq %rax, 16(%rsp)
/* Get current time. */
movq %rsp, %rdi
xorl %esi, %esi
/* This call works because we directly jump to a system call entry
which preserves all the registers. */
call JUMPTARGET(__gettimeofday)
/* 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
movl 32(%rsp), %esi
LOAD_FUTEX_WAIT (%esi)
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 $40, %rsp
cfi_adjust_cfa_offset(-40)
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(72)
cfi_offset(%r8, -16)
cfi_offset(%r9, -24)
cfi_offset(%r12, -32)
cfi_offset(%r13, -40)
/* Check whether the time expired. */
7: cmpl $-ETIMEDOUT, %ecx
jne 1b
8: movl $ETIMEDOUT, %eax
jmp 6b
#endif
cfi_endproc
.size __lll_robust_timedlock_wait,.-__lll_robust_timedlock_wait
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