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|
/* Copyright (C) 2002-2012 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 <shlib-compat.h>
#include <lowlevellock.h>
#include <lowlevelcond.h>
#include <pthread-errnos.h>
#include <pthread-pi-defines.h>
#include <kernel-features.h>
#include <stap-probe.h>
.text
/* int pthread_cond_timedwait (pthread_cond_t *cond, pthread_mutex_t *mutex,
const struct timespec *abstime) */
.globl __pthread_cond_timedwait
.type __pthread_cond_timedwait, @function
.align 16
__pthread_cond_timedwait:
.LSTARTCODE:
cfi_startproc
#ifdef SHARED
cfi_personality(DW_EH_PE_pcrel | DW_EH_PE_sdata4 | DW_EH_PE_indirect,
DW.ref.__gcc_personality_v0)
cfi_lsda(DW_EH_PE_pcrel | DW_EH_PE_sdata4, .LexceptSTART)
#else
cfi_personality(DW_EH_PE_udata4, __gcc_personality_v0)
cfi_lsda(DW_EH_PE_udata4, .LexceptSTART)
#endif
pushl %ebp
cfi_adjust_cfa_offset(4)
cfi_rel_offset(%ebp, 0)
pushl %edi
cfi_adjust_cfa_offset(4)
cfi_rel_offset(%edi, 0)
pushl %esi
cfi_adjust_cfa_offset(4)
cfi_rel_offset(%esi, 0)
pushl %ebx
cfi_adjust_cfa_offset(4)
cfi_rel_offset(%ebx, 0)
movl 20(%esp), %ebx
movl 28(%esp), %ebp
LIBC_PROBE (cond_timedwait, 3, %ebx, 24(%esp), %ebp)
cmpl $1000000000, 4(%ebp)
movl $EINVAL, %eax
jae 18f
/* Get internal lock. */
movl $1, %edx
xorl %eax, %eax
LOCK
#if cond_lock == 0
cmpxchgl %edx, (%ebx)
#else
cmpxchgl %edx, cond_lock(%ebx)
#endif
jnz 1f
/* Store the reference to the mutex. If there is already a
different value in there this is a bad user bug. */
2: cmpl $-1, dep_mutex(%ebx)
movl 24(%esp), %eax
je 17f
movl %eax, dep_mutex(%ebx)
/* Unlock the mutex. */
17: xorl %edx, %edx
call __pthread_mutex_unlock_usercnt
testl %eax, %eax
jne 16f
addl $1, total_seq(%ebx)
adcl $0, total_seq+4(%ebx)
addl $1, cond_futex(%ebx)
addl $(1 << nwaiters_shift), cond_nwaiters(%ebx)
#define FRAME_SIZE 32
subl $FRAME_SIZE, %esp
cfi_adjust_cfa_offset(FRAME_SIZE)
cfi_remember_state
/* Get and store current wakeup_seq value. */
movl wakeup_seq(%ebx), %edi
movl wakeup_seq+4(%ebx), %edx
movl broadcast_seq(%ebx), %eax
movl %edi, 12(%esp)
movl %edx, 16(%esp)
movl %eax, 20(%esp)
/* Reset the pi-requeued flag. */
8: movl $0, 24(%esp)
/* Get the current time. */
movl %ebx, %edx
#ifdef __NR_clock_gettime
/* Get the clock number. */
movl cond_nwaiters(%ebx), %ebx
andl $((1 << nwaiters_shift) - 1), %ebx
/* Only clocks 0 and 1 are allowed so far. Both are handled in the
kernel. */
leal 4(%esp), %ecx
movl $__NR_clock_gettime, %eax
ENTER_KERNEL
movl %edx, %ebx
/* Compute relative timeout. */
movl (%ebp), %ecx
movl 4(%ebp), %edx
subl 4(%esp), %ecx
subl 8(%esp), %edx
#else
/* Get the current time. */
leal 4(%esp), %ebx
xorl %ecx, %ecx
movl $__NR_gettimeofday, %eax
ENTER_KERNEL
movl %edx, %ebx
/* Compute relative timeout. */
movl 8(%esp), %eax
movl $1000, %edx
mul %edx /* Milli seconds to nano seconds. */
movl (%ebp), %ecx
movl 4(%ebp), %edx
subl 4(%esp), %ecx
subl %eax, %edx
#endif
jns 12f
addl $1000000000, %edx
subl $1, %ecx
12: testl %ecx, %ecx
movl $-ETIMEDOUT, %esi
js 6f
/* Store relative timeout. */
21: movl %ecx, 4(%esp)
movl %edx, 8(%esp)
movl cond_futex(%ebx), %edi
movl %edi, 28(%esp)
/* Unlock. */
LOCK
#if cond_lock == 0
subl $1, (%ebx)
#else
subl $1, cond_lock(%ebx)
#endif
jne 3f
.LcleanupSTART:
4: call __pthread_enable_asynccancel
movl %eax, (%esp)
#if FUTEX_PRIVATE_FLAG > 255
xorl %ecx, %ecx
#endif
cmpl $-1, dep_mutex(%ebx)
sete %cl
je 40f
movl dep_mutex(%ebx), %edi
/* Requeue to a non-robust PI mutex if the PI bit is set and
the robust bit is not set. */
movl MUTEX_KIND(%edi), %eax
andl $(ROBUST_BIT|PI_BIT), %eax
cmpl $PI_BIT, %eax
jne 40f
movl $(FUTEX_WAIT_REQUEUE_PI|FUTEX_PRIVATE_FLAG), %ecx
/* The following only works like this because we only support
two clocks, represented using a single bit. */
testl $1, cond_nwaiters(%ebx)
/* XXX Need to implement using sete instead of a jump. */
jne 42f
orl $FUTEX_CLOCK_REALTIME, %ecx
/* Requeue-PI uses absolute timeout */
42: leal (%ebp), %esi
movl 28(%esp), %edx
addl $cond_futex, %ebx
movl $SYS_futex, %eax
ENTER_KERNEL
subl $cond_futex, %ebx
movl %eax, %esi
/* Set the pi-requeued flag only if the kernel has returned 0. The
kernel does not hold the mutex on ETIMEDOUT or any other error. */
cmpl $0, %eax
sete 24(%esp)
je 41f
/* Normal and PI futexes dont mix. Use normal futex functions only
if the kernel does not support the PI futex functions. */
cmpl $-ENOSYS, %eax
jne 41f
xorl %ecx, %ecx
40: subl $1, %ecx
#ifdef __ASSUME_PRIVATE_FUTEX
andl $FUTEX_PRIVATE_FLAG, %ecx
#else
andl %gs:PRIVATE_FUTEX, %ecx
#endif
#if FUTEX_WAIT != 0
addl $FUTEX_WAIT, %ecx
#endif
leal 4(%esp), %esi
movl 28(%esp), %edx
addl $cond_futex, %ebx
.Ladd_cond_futex:
movl $SYS_futex, %eax
ENTER_KERNEL
subl $cond_futex, %ebx
.Lsub_cond_futex:
movl %eax, %esi
41: movl (%esp), %eax
call __pthread_disable_asynccancel
.LcleanupEND:
/* Lock. */
movl $1, %edx
xorl %eax, %eax
LOCK
#if cond_lock == 0
cmpxchgl %edx, (%ebx)
#else
cmpxchgl %edx, cond_lock(%ebx)
#endif
jnz 5f
6: movl broadcast_seq(%ebx), %eax
cmpl 20(%esp), %eax
jne 23f
movl woken_seq(%ebx), %eax
movl woken_seq+4(%ebx), %ecx
movl wakeup_seq(%ebx), %edi
movl wakeup_seq+4(%ebx), %edx
cmpl 16(%esp), %edx
jne 7f
cmpl 12(%esp), %edi
je 15f
7: cmpl %ecx, %edx
jne 9f
cmp %eax, %edi
jne 9f
15: cmpl $-ETIMEDOUT, %esi
jne 8b
addl $1, wakeup_seq(%ebx)
adcl $0, wakeup_seq+4(%ebx)
addl $1, cond_futex(%ebx)
movl $ETIMEDOUT, %esi
jmp 14f
23: xorl %esi, %esi
jmp 24f
9: xorl %esi, %esi
14: addl $1, woken_seq(%ebx)
adcl $0, woken_seq+4(%ebx)
24: subl $(1 << nwaiters_shift), cond_nwaiters(%ebx)
/* Wake up a thread which wants to destroy the condvar object. */
movl total_seq(%ebx), %eax
andl total_seq+4(%ebx), %eax
cmpl $0xffffffff, %eax
jne 25f
movl cond_nwaiters(%ebx), %eax
andl $~((1 << nwaiters_shift) - 1), %eax
jne 25f
addl $cond_nwaiters, %ebx
movl $SYS_futex, %eax
#if FUTEX_PRIVATE_FLAG > 255
xorl %ecx, %ecx
#endif
cmpl $-1, dep_mutex-cond_nwaiters(%ebx)
sete %cl
subl $1, %ecx
#ifdef __ASSUME_PRIVATE_FUTEX
andl $FUTEX_PRIVATE_FLAG, %ecx
#else
andl %gs:PRIVATE_FUTEX, %ecx
#endif
addl $FUTEX_WAKE, %ecx
movl $1, %edx
ENTER_KERNEL
subl $cond_nwaiters, %ebx
25: LOCK
#if cond_lock == 0
subl $1, (%ebx)
#else
subl $1, cond_lock(%ebx)
#endif
jne 10f
11: movl 24+FRAME_SIZE(%esp), %eax
/* With requeue_pi, the mutex lock is held in the kernel. */
movl 24(%esp), %ecx
testl %ecx, %ecx
jnz 27f
call __pthread_mutex_cond_lock
26: addl $FRAME_SIZE, %esp
cfi_adjust_cfa_offset(-FRAME_SIZE);
/* We return the result of the mutex_lock operation if it failed. */
testl %eax, %eax
#ifdef HAVE_CMOV
cmovel %esi, %eax
#else
jne 22f
movl %esi, %eax
22:
#endif
18: 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)
popl %ebp
cfi_adjust_cfa_offset(-4)
cfi_restore(%ebp)
ret
cfi_restore_state
27: call __pthread_mutex_cond_lock_adjust
xorl %eax, %eax
jmp 26b
cfi_adjust_cfa_offset(-FRAME_SIZE);
/* Initial locking failed. */
1:
#if cond_lock == 0
movl %ebx, %edx
#else
leal cond_lock(%ebx), %edx
#endif
#if (LLL_SHARED-LLL_PRIVATE) > 255
xorl %ecx, %ecx
#endif
cmpl $-1, dep_mutex(%ebx)
setne %cl
subl $1, %ecx
andl $(LLL_SHARED-LLL_PRIVATE), %ecx
#if LLL_PRIVATE != 0
addl $LLL_PRIVATE, %ecx
#endif
call __lll_lock_wait
jmp 2b
/* The initial unlocking of the mutex failed. */
16:
LOCK
#if cond_lock == 0
subl $1, (%ebx)
#else
subl $1, cond_lock(%ebx)
#endif
jne 18b
movl %eax, %esi
#if cond_lock == 0
movl %ebx, %eax
#else
leal cond_lock(%ebx), %eax
#endif
#if (LLL_SHARED-LLL_PRIVATE) > 255
xorl %ecx, %ecx
#endif
cmpl $-1, dep_mutex(%ebx)
setne %cl
subl $1, %ecx
andl $(LLL_SHARED-LLL_PRIVATE), %ecx
#if LLL_PRIVATE != 0
addl $LLL_PRIVATE, %ecx
#endif
call __lll_unlock_wake
movl %esi, %eax
jmp 18b
cfi_adjust_cfa_offset(FRAME_SIZE)
/* Unlock in loop requires wakeup. */
3:
#if cond_lock == 0
movl %ebx, %eax
#else
leal cond_lock(%ebx), %eax
#endif
#if (LLL_SHARED-LLL_PRIVATE) > 255
xorl %ecx, %ecx
#endif
cmpl $-1, dep_mutex(%ebx)
setne %cl
subl $1, %ecx
andl $(LLL_SHARED-LLL_PRIVATE), %ecx
#if LLL_PRIVATE != 0
addl $LLL_PRIVATE, %ecx
#endif
call __lll_unlock_wake
jmp 4b
/* Locking in loop failed. */
5:
#if cond_lock == 0
movl %ebx, %edx
#else
leal cond_lock(%ebx), %edx
#endif
#if (LLL_SHARED-LLL_PRIVATE) > 255
xorl %ecx, %ecx
#endif
cmpl $-1, dep_mutex(%ebx)
setne %cl
subl $1, %ecx
andl $(LLL_SHARED-LLL_PRIVATE), %ecx
#if LLL_PRIVATE != 0
addl $LLL_PRIVATE, %ecx
#endif
call __lll_lock_wait
jmp 6b
/* Unlock after loop requires wakeup. */
10:
#if cond_lock == 0
movl %ebx, %eax
#else
leal cond_lock(%ebx), %eax
#endif
#if (LLL_SHARED-LLL_PRIVATE) > 255
xorl %ecx, %ecx
#endif
cmpl $-1, dep_mutex(%ebx)
setne %cl
subl $1, %ecx
andl $(LLL_SHARED-LLL_PRIVATE), %ecx
#if LLL_PRIVATE != 0
addl $LLL_PRIVATE, %ecx
#endif
call __lll_unlock_wake
jmp 11b
.size __pthread_cond_timedwait, .-__pthread_cond_timedwait
versioned_symbol (libpthread, __pthread_cond_timedwait, pthread_cond_timedwait,
GLIBC_2_3_2)
.type __condvar_tw_cleanup2, @function
__condvar_tw_cleanup2:
subl $cond_futex, %ebx
.size __condvar_tw_cleanup2, .-__condvar_tw_cleanup2
.type __condvar_tw_cleanup, @function
__condvar_tw_cleanup:
movl %eax, %esi
/* Get internal lock. */
movl $1, %edx
xorl %eax, %eax
LOCK
#if cond_lock == 0
cmpxchgl %edx, (%ebx)
#else
cmpxchgl %edx, cond_lock(%ebx)
#endif
jz 1f
#if cond_lock == 0
movl %ebx, %edx
#else
leal cond_lock(%ebx), %edx
#endif
#if (LLL_SHARED-LLL_PRIVATE) > 255
xorl %ecx, %ecx
#endif
cmpl $-1, dep_mutex(%ebx)
setne %cl
subl $1, %ecx
andl $(LLL_SHARED-LLL_PRIVATE), %ecx
#if LLL_PRIVATE != 0
addl $LLL_PRIVATE, %ecx
#endif
call __lll_lock_wait
1: movl broadcast_seq(%ebx), %eax
cmpl 20(%esp), %eax
jne 3f
/* We increment the wakeup_seq counter only if it is lower than
total_seq. If this is not the case the thread was woken and
then canceled. In this case we ignore the signal. */
movl total_seq(%ebx), %eax
movl total_seq+4(%ebx), %edi
cmpl wakeup_seq+4(%ebx), %edi
jb 6f
ja 7f
cmpl wakeup_seq(%ebx), %eax
jbe 7f
6: addl $1, wakeup_seq(%ebx)
adcl $0, wakeup_seq+4(%ebx)
addl $1, cond_futex(%ebx)
7: addl $1, woken_seq(%ebx)
adcl $0, woken_seq+4(%ebx)
3: subl $(1 << nwaiters_shift), cond_nwaiters(%ebx)
/* Wake up a thread which wants to destroy the condvar object. */
xorl %edi, %edi
movl total_seq(%ebx), %eax
andl total_seq+4(%ebx), %eax
cmpl $0xffffffff, %eax
jne 4f
movl cond_nwaiters(%ebx), %eax
andl $~((1 << nwaiters_shift) - 1), %eax
jne 4f
addl $cond_nwaiters, %ebx
movl $SYS_futex, %eax
#if FUTEX_PRIVATE_FLAG > 255
xorl %ecx, %ecx
#endif
cmpl $-1, dep_mutex-cond_nwaiters(%ebx)
sete %cl
subl $1, %ecx
#ifdef __ASSUME_PRIVATE_FUTEX
andl $FUTEX_PRIVATE_FLAG, %ecx
#else
andl %gs:PRIVATE_FUTEX, %ecx
#endif
addl $FUTEX_WAKE, %ecx
movl $1, %edx
ENTER_KERNEL
subl $cond_nwaiters, %ebx
movl $1, %edi
4: LOCK
#if cond_lock == 0
subl $1, (%ebx)
#else
subl $1, cond_lock(%ebx)
#endif
je 2f
#if cond_lock == 0
movl %ebx, %eax
#else
leal cond_lock(%ebx), %eax
#endif
#if (LLL_SHARED-LLL_PRIVATE) > 255
xorl %ecx, %ecx
#endif
cmpl $-1, dep_mutex(%ebx)
setne %cl
subl $1, %ecx
andl $(LLL_SHARED-LLL_PRIVATE), %ecx
#if LLL_PRIVATE != 0
addl $LLL_PRIVATE, %ecx
#endif
call __lll_unlock_wake
/* Wake up all waiters to make sure no signal gets lost. */
2: testl %edi, %edi
jnz 5f
addl $cond_futex, %ebx
#if FUTEX_PRIVATE_FLAG > 255
xorl %ecx, %ecx
#endif
cmpl $-1, dep_mutex-cond_futex(%ebx)
sete %cl
subl $1, %ecx
#ifdef __ASSUME_PRIVATE_FUTEX
andl $FUTEX_PRIVATE_FLAG, %ecx
#else
andl %gs:PRIVATE_FUTEX, %ecx
#endif
addl $FUTEX_WAKE, %ecx
movl $SYS_futex, %eax
movl $0x7fffffff, %edx
ENTER_KERNEL
5: movl 24+FRAME_SIZE(%esp), %eax
call __pthread_mutex_cond_lock
movl %esi, (%esp)
.LcallUR:
call _Unwind_Resume
hlt
.LENDCODE:
cfi_endproc
.size __condvar_tw_cleanup, .-__condvar_tw_cleanup
.section .gcc_except_table,"a",@progbits
.LexceptSTART:
.byte DW_EH_PE_omit # @LPStart format (omit)
.byte DW_EH_PE_omit # @TType format (omit)
.byte DW_EH_PE_sdata4 # call-site format
# DW_EH_PE_sdata4
.uleb128 .Lcstend-.Lcstbegin
.Lcstbegin:
.long .LcleanupSTART-.LSTARTCODE
.long .Ladd_cond_futex-.LcleanupSTART
.long __condvar_tw_cleanup-.LSTARTCODE
.uleb128 0
.long .Ladd_cond_futex-.LSTARTCODE
.long .Lsub_cond_futex-.Ladd_cond_futex
.long __condvar_tw_cleanup2-.LSTARTCODE
.uleb128 0
.long .Lsub_cond_futex-.LSTARTCODE
.long .LcleanupEND-.Lsub_cond_futex
.long __condvar_tw_cleanup-.LSTARTCODE
.uleb128 0
.long .LcallUR-.LSTARTCODE
.long .LENDCODE-.LcallUR
.long 0
.uleb128 0
.Lcstend:
#ifdef SHARED
.hidden DW.ref.__gcc_personality_v0
.weak DW.ref.__gcc_personality_v0
.section .gnu.linkonce.d.DW.ref.__gcc_personality_v0,"aw",@progbits
.align 4
.type DW.ref.__gcc_personality_v0, @object
.size DW.ref.__gcc_personality_v0, 4
DW.ref.__gcc_personality_v0:
.long __gcc_personality_v0
#endif
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