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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 <lowlevellock.h>
#include <lowlevelrwlock.h>
#include <pthread-errnos.h>
#include <kernel-features.h>
.text
.globl pthread_rwlock_timedwrlock
.type pthread_rwlock_timedwrlock,@function
.align 16
pthread_rwlock_timedwrlock:
cfi_startproc
pushq %r12
cfi_adjust_cfa_offset(8)
cfi_rel_offset(%r12, 0)
pushq %r13
cfi_adjust_cfa_offset(8)
cfi_rel_offset(%r13, 0)
#ifdef __ASSUME_FUTEX_CLOCK_REALTIME
# define VALREG %edx
#else
pushq %r14
cfi_adjust_cfa_offset(8)
cfi_rel_offset(%r14, 0)
subq $16, %rsp
cfi_adjust_cfa_offset(16)
# define VALREG %r14d
#endif
movq %rdi, %r12
movq %rsi, %r13
/* Get the lock. */
movl $1, %esi
xorl %eax, %eax
LOCK
#if MUTEX == 0
cmpxchgl %esi, (%rdi)
#else
cmpxchgl %esi, MUTEX(%rdi)
#endif
jnz 1f
2: movl WRITER(%r12), %eax
testl %eax, %eax
jne 14f
cmpl $0, NR_READERS(%r12)
je 5f
/* Check the value of the timeout parameter. */
3: cmpq $1000000000, 8(%r13)
jae 19f
incl WRITERS_QUEUED(%r12)
je 4f
movl WRITERS_WAKEUP(%r12), VALREG
LOCK
#if MUTEX == 0
decl (%r12)
#else
decl MUTEX(%r12)
#endif
jne 10f
11:
#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, (%r13)
js 16f /* Time is already up. */
movl $FUTEX_PRIVATE_FLAG|FUTEX_WAIT_BITSET|FUTEX_CLOCK_REALTIME, %esi
xorl PSHARED(%r12), %esi
movq %r13, %r10
movl $0xffffffff, %r9d
#ifndef __ASSUME_FUTEX_CLOCK_REALTIME
movl %r14d, %edx
#endif
21: leaq WRITERS_WAKEUP(%r12), %rdi
movl $SYS_futex, %eax
syscall
movq %rax, %rdx
#ifndef __ASSUME_FUTEX_CLOCK_REALTIME
.subsection 2
.Lreltmo:
/* 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), %rcx
movq 8(%r13), %rdi
subq (%rsp), %rcx
subq %rax, %rdi
jns 15f
addq $1000000000, %rdi
decq %rcx
15: testq %rcx, %rcx
js 16f /* Time is already up. */
/* Futex call. */
movq %rcx, (%rsp) /* Store relative timeout. */
movq %rdi, 8(%rsp)
# ifdef __ASSUME_PRIVATE_FUTEX
movl $FUTEX_PRIVATE_FLAG|FUTEX_WAIT, %esi
xorl PSHARED(%r12), %esi
# else
# if FUTEX_WAIT == 0
movl PSHARED(%r12), %esi
# else
movl $FUTEX_WAIT, %esi
orl PSHARED(%r12), %esi
# endif
xorl %fs:PRIVATE_FUTEX, %esi
# endif
movq %rsp, %r10
movl %r14d, %edx
jmp 21b
.previous
#endif
17: /* Reget the lock. */
movl $1, %esi
xorl %eax, %eax
LOCK
#if MUTEX == 0
cmpxchgl %esi, (%r12)
#else
cmpxchgl %esi, MUTEX(%r12)
#endif
jnz 12f
13: decl WRITERS_QUEUED(%r12)
cmpq $-ETIMEDOUT, %rdx
jne 2b
18: movl $ETIMEDOUT, %edx
jmp 9f
5: xorl %edx, %edx
movl %fs:TID, %eax
movl %eax, WRITER(%r12)
9: LOCK
#if MUTEX == 0
decl (%r12)
#else
decl MUTEX(%r12)
#endif
jne 6f
7: movq %rdx, %rax
#ifndef __ASSUME_FUTEX_CLOCK_REALTIME
addq $16, %rsp
cfi_adjust_cfa_offset(-16)
popq %r14
cfi_adjust_cfa_offset(-8)
cfi_restore(%r14)
#endif
popq %r13
cfi_adjust_cfa_offset(-8)
cfi_restore(%r13)
popq %r12
cfi_adjust_cfa_offset(-8)
cfi_restore(%r12)
retq
#ifdef __ASSUME_FUTEX_CLOCK_REALTIME
cfi_adjust_cfa_offset(16)
cfi_rel_offset(%r12, 8)
cfi_rel_offset(%r13, 0)
#else
cfi_adjust_cfa_offset(40)
cfi_offset(%r12, -16)
cfi_offset(%r13, -24)
cfi_offset(%r14, -32)
#endif
1: movl PSHARED(%rdi), %esi
#if MUTEX != 0
addq $MUTEX, %rdi
#endif
callq __lll_lock_wait
jmp 2b
14: cmpl %fs:TID, %eax
jne 3b
20: movl $EDEADLK, %edx
jmp 9b
6: movl PSHARED(%r12), %esi
#if MUTEX == 0
movq %r12, %rdi
#else
leal MUTEX(%r12), %rdi
#endif
callq __lll_unlock_wake
jmp 7b
/* Overflow. */
4: decl WRITERS_QUEUED(%r12)
movl $EAGAIN, %edx
jmp 9b
10: movl PSHARED(%r12), %esi
#if MUTEX == 0
movq %r12, %rdi
#else
leaq MUTEX(%r12), %rdi
#endif
callq __lll_unlock_wake
jmp 11b
12: movl PSHARED(%r12), %esi
#if MUTEX == 0
movq %r12, %rdi
#else
leaq MUTEX(%r12), %rdi
#endif
callq __lll_lock_wait
jmp 13b
16: movq $-ETIMEDOUT, %rdx
jmp 17b
19: movl $EINVAL, %edx
jmp 9b
cfi_endproc
.size pthread_rwlock_timedwrlock,.-pthread_rwlock_timedwrlock
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