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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 <tcb-offsets.h>
#include <pthread-errnos.h>
#include <pthread-pi-defines.h>
#include <kernel-features.h>
#include <stap-probe.h>
.text
/* int pthread_cond_wait (pthread_cond_t *cond, pthread_mutex_t *mutex) */
.globl __pthread_cond_wait
.type __pthread_cond_wait, @function
.align 16
__pthread_cond_wait:
.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)
xorl %esi, %esi
movl 20(%esp), %ebx
LIBC_PROBE (cond_wait, 2, 24(%esp), %ebx)
/* 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 15f
movl %eax, dep_mutex(%ebx)
/* Unlock the mutex. */
15: xorl %edx, %edx
call __pthread_mutex_unlock_usercnt
testl %eax, %eax
jne 12f
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 20
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, 4(%esp)
movl %edx, 8(%esp)
movl %eax, 12(%esp)
/* Reset the pi-requeued flag. */
8: movl $0, 16(%esp)
movl cond_futex(%ebx), %ebp
/* 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)
xorl %ecx, %ecx
cmpl $-1, dep_mutex(%ebx)
sete %cl
je 18f
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 18f
90:
movl $(FUTEX_WAIT_REQUEUE_PI|FUTEX_PRIVATE_FLAG), %ecx
movl %ebp, %edx
xorl %esi, %esi
addl $cond_futex, %ebx
.Ladd_cond_futex_pi:
movl $SYS_futex, %eax
ENTER_KERNEL
subl $cond_futex, %ebx
.Lsub_cond_futex_pi:
/* Set the pi-requeued flag only if the kernel has returned 0. The
kernel does not hold the mutex on error. */
cmpl $0, %eax
sete 16(%esp)
je 19f
cmpl $-EAGAIN, %eax
je 91f
/* 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 19f
xorl %ecx, %ecx
18: 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
movl %ebp, %edx
addl $cond_futex, %ebx
.Ladd_cond_futex:
movl $SYS_futex, %eax
ENTER_KERNEL
subl $cond_futex, %ebx
.Lsub_cond_futex:
19: 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 12(%esp), %eax
jne 16f
movl woken_seq(%ebx), %eax
movl woken_seq+4(%ebx), %ecx
movl wakeup_seq(%ebx), %edi
movl wakeup_seq+4(%ebx), %edx
cmpl 8(%esp), %edx
jne 7f
cmpl 4(%esp), %edi
je 8b
7: cmpl %ecx, %edx
jne 9f
cmp %eax, %edi
je 8b
9: addl $1, woken_seq(%ebx)
adcl $0, woken_seq+4(%ebx)
/* Unlock */
16: 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 17f
movl cond_nwaiters(%ebx), %eax
andl $~((1 << nwaiters_shift) - 1), %eax
jne 17f
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
17: LOCK
#if cond_lock == 0
subl $1, (%ebx)
#else
subl $1, cond_lock(%ebx)
#endif
jne 10f
/* With requeue_pi, the mutex lock is held in the kernel. */
11: movl 24+FRAME_SIZE(%esp), %eax
movl 16(%esp), %ecx
testl %ecx, %ecx
jnz 21f
call __pthread_mutex_cond_lock
20: addl $FRAME_SIZE, %esp
cfi_adjust_cfa_offset(-FRAME_SIZE);
14: 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)
/* We return the result of the mutex_lock operation. */
ret
cfi_restore_state
21: call __pthread_mutex_cond_lock_adjust
xorl %eax, %eax
jmp 20b
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. */
12:
LOCK
#if cond_lock == 0
subl $1, (%ebx)
#else
subl $1, cond_lock(%ebx)
#endif
jne 14b
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 14b
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
91:
.LcleanupSTART2:
/* FUTEX_WAIT_REQUEUE_PI returned EAGAIN. We need to
call it again. */
/* 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 92f
#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
92:
/* Increment the cond_futex value again, so it can be used as a new
expected value. */
addl $1, cond_futex(%ebx)
movl cond_futex(%ebx), %ebp
/* Unlock. */
LOCK
#if cond_lock == 0
subl $1, (%ebx)
#else
subl $1, cond_lock(%ebx)
#endif
je 93f
#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
93:
/* Set the rest of SYS_futex args for FUTEX_WAIT_REQUEUE_PI. */
xorl %ecx, %ecx
movl dep_mutex(%ebx), %edi
jmp 90b
.LcleanupEND2:
.size __pthread_cond_wait, .-__pthread_cond_wait
versioned_symbol (libpthread, __pthread_cond_wait, pthread_cond_wait,
GLIBC_2_3_2)
.type __condvar_w_cleanup2, @function
__condvar_w_cleanup2:
subl $cond_futex, %ebx
.size __condvar_w_cleanup2, .-__condvar_w_cleanup2
.LSbl4:
.type __condvar_w_cleanup, @function
__condvar_w_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 12(%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_w_cleanup, .-__condvar_w_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_pi-.LcleanupSTART
.long __condvar_w_cleanup-.LSTARTCODE
.uleb128 0
.long .Ladd_cond_futex_pi-.LSTARTCODE
.long .Lsub_cond_futex_pi-.Ladd_cond_futex_pi
.long __condvar_w_cleanup2-.LSTARTCODE
.uleb128 0
.long .Lsub_cond_futex_pi-.LSTARTCODE
.long .Ladd_cond_futex-.Lsub_cond_futex_pi
.long __condvar_w_cleanup-.LSTARTCODE
.uleb128 0
.long .Ladd_cond_futex-.LSTARTCODE
.long .Lsub_cond_futex-.Ladd_cond_futex
.long __condvar_w_cleanup2-.LSTARTCODE
.uleb128 0
.long .Lsub_cond_futex-.LSTARTCODE
.long .LcleanupEND-.Lsub_cond_futex
.long __condvar_w_cleanup-.LSTARTCODE
.uleb128 0
.long .LcleanupSTART2-.LSTARTCODE
.long .LcleanupEND2-.LcleanupSTART2
.long __condvar_w_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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