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|
/* Copyright (C) 2002-2007, 2009, 2011 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-pi-defines.h>
#include <pthread-errnos.h>
#include <kernel-features.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
#define FRAME_SIZE (32+8)
leaq -FRAME_SIZE(%rsp), %rsp
cfi_adjust_cfa_offset(FRAME_SIZE)
/* Stack frame:
rsp + 32
+--------------------------+
rsp + 24 | old wake_seq value |
+--------------------------+
rsp + 16 | mutex pointer |
+--------------------------+
rsp + 8 | condvar pointer |
+--------------------------+
rsp + 4 | old broadcast_seq value |
+--------------------------+
rsp + 0 | old cancellation mode |
+--------------------------+
*/
LP_OP(cmp) $-1, dep_mutex(%rdi)
/* Prepare structure passed to cancellation handler. */
movq %rdi, 8(%rsp)
movq %rsi, 16(%rsp)
je 15f
mov %RSI_LP, dep_mutex(%rdi)
/* Get internal lock. */
15: movl $1, %esi
xorl %eax, %eax
LOCK
#if cond_lock == 0
cmpxchgl %esi, (%rdi)
#else
cmpxchgl %esi, cond_lock(%rdi)
#endif
jne 1f
/* Unlock the mutex. */
2: movq 16(%rsp), %rdi
xorl %esi, %esi
callq __pthread_mutex_unlock_usercnt
testl %eax, %eax
jne 12f
movq 8(%rsp), %rdi
incq total_seq(%rdi)
incl cond_futex(%rdi)
addl $(1 << nwaiters_shift), cond_nwaiters(%rdi)
/* Get and store current wakeup_seq value. */
movq 8(%rsp), %rdi
movq wakeup_seq(%rdi), %r9
movl broadcast_seq(%rdi), %edx
movq %r9, 24(%rsp)
movl %edx, 4(%rsp)
/* Unlock. */
8: movl cond_futex(%rdi), %edx
LOCK
#if cond_lock == 0
decl (%rdi)
#else
decl cond_lock(%rdi)
#endif
jne 3f
.LcleanupSTART:
4: callq __pthread_enable_asynccancel
movl %eax, (%rsp)
xorq %r10, %r10
LP_OP(cmp) $-1, dep_mutex(%rdi)
leaq cond_futex(%rdi), %rdi
movl $FUTEX_WAIT, %esi
je 60f
mov dep_mutex-cond_futex(%rdi), %R8_LP
/* Requeue to a non-robust PI mutex if the PI bit is set and
the robust bit is not set. */
movl MUTEX_KIND(%r8), %eax
andl $(ROBUST_BIT|PI_BIT), %eax
cmpl $PI_BIT, %eax
jne 61f
90:
movl $(FUTEX_WAIT_REQUEUE_PI|FUTEX_PRIVATE_FLAG), %esi
movl $SYS_futex, %eax
syscall
movl $1, %r8d
cmpq $-EAGAIN, %rax
je 91f
#ifdef __ASSUME_REQUEUE_PI
jmp 62f
#else
cmpq $-4095, %rax
jnae 62f
# ifndef __ASSUME_PRIVATE_FUTEX
movl $FUTEX_WAIT, %esi
# endif
#endif
61:
#ifdef __ASSUME_PRIVATE_FUTEX
movl $(FUTEX_WAIT|FUTEX_PRIVATE_FLAG), %esi
#else
orl %fs:PRIVATE_FUTEX, %esi
#endif
60: xorl %r8d, %r8d
movl $SYS_futex, %eax
syscall
62: movl (%rsp), %edi
callq __pthread_disable_asynccancel
.LcleanupEND:
/* Lock. */
movq 8(%rsp), %rdi
movl $1, %esi
xorl %eax, %eax
LOCK
#if cond_lock == 0
cmpxchgl %esi, (%rdi)
#else
cmpxchgl %esi, cond_lock(%rdi)
#endif
jnz 5f
6: movl broadcast_seq(%rdi), %edx
movq woken_seq(%rdi), %rax
movq wakeup_seq(%rdi), %r9
cmpl 4(%rsp), %edx
jne 16f
cmpq 24(%rsp), %r9
jbe 8b
cmpq %rax, %r9
jna 8b
incq woken_seq(%rdi)
/* Unlock */
16: subl $(1 << nwaiters_shift), cond_nwaiters(%rdi)
/* Wake up a thread which wants to destroy the condvar object. */
cmpq $0xffffffffffffffff, total_seq(%rdi)
jne 17f
movl cond_nwaiters(%rdi), %eax
andl $~((1 << nwaiters_shift) - 1), %eax
jne 17f
addq $cond_nwaiters, %rdi
LP_OP(cmp) $-1, dep_mutex-cond_nwaiters(%rdi)
movl $1, %edx
#ifdef __ASSUME_PRIVATE_FUTEX
movl $FUTEX_WAKE, %eax
movl $(FUTEX_WAKE|FUTEX_PRIVATE_FLAG), %esi
cmove %eax, %esi
#else
movl $0, %eax
movl %fs:PRIVATE_FUTEX, %esi
cmove %eax, %esi
orl $FUTEX_WAKE, %esi
#endif
movl $SYS_futex, %eax
syscall
subq $cond_nwaiters, %rdi
17: LOCK
#if cond_lock == 0
decl (%rdi)
#else
decl cond_lock(%rdi)
#endif
jne 10f
/* If requeue_pi is used the kernel performs the locking of the
mutex. */
11: movq 16(%rsp), %rdi
testl %r8d, %r8d
jnz 18f
callq __pthread_mutex_cond_lock
14: leaq FRAME_SIZE(%rsp), %rsp
cfi_adjust_cfa_offset(-FRAME_SIZE)
/* We return the result of the mutex_lock operation. */
retq
cfi_adjust_cfa_offset(FRAME_SIZE)
18: callq __pthread_mutex_cond_lock_adjust
xorl %eax, %eax
jmp 14b
/* Initial locking failed. */
1:
#if cond_lock != 0
addq $cond_lock, %rdi
#endif
LP_OP(cmp) $-1, dep_mutex-cond_lock(%rdi)
movl $LLL_PRIVATE, %eax
movl $LLL_SHARED, %esi
cmovne %eax, %esi
callq __lll_lock_wait
jmp 2b
/* Unlock in loop requires wakeup. */
3:
#if cond_lock != 0
addq $cond_lock, %rdi
#endif
LP_OP(cmp) $-1, dep_mutex-cond_lock(%rdi)
movl $LLL_PRIVATE, %eax
movl $LLL_SHARED, %esi
cmovne %eax, %esi
/* The call preserves %rdx. */
callq __lll_unlock_wake
#if cond_lock != 0
subq $cond_lock, %rdi
#endif
jmp 4b
/* Locking in loop failed. */
5:
#if cond_lock != 0
addq $cond_lock, %rdi
#endif
LP_OP(cmp) $-1, dep_mutex-cond_lock(%rdi)
movl $LLL_PRIVATE, %eax
movl $LLL_SHARED, %esi
cmovne %eax, %esi
callq __lll_lock_wait
#if cond_lock != 0
subq $cond_lock, %rdi
#endif
jmp 6b
/* Unlock after loop requires wakeup. */
10:
#if cond_lock != 0
addq $cond_lock, %rdi
#endif
LP_OP(cmp) $-1, dep_mutex-cond_lock(%rdi)
movl $LLL_PRIVATE, %eax
movl $LLL_SHARED, %esi
cmovne %eax, %esi
callq __lll_unlock_wake
jmp 11b
/* The initial unlocking of the mutex failed. */
12: movq %rax, %r10
movq 8(%rsp), %rdi
LOCK
#if cond_lock == 0
decl (%rdi)
#else
decl cond_lock(%rdi)
#endif
je 13f
#if cond_lock != 0
addq $cond_lock, %rdi
#endif
LP_OP(cmp) $-1, dep_mutex-cond_lock(%rdi)
movl $LLL_PRIVATE, %eax
movl $LLL_SHARED, %esi
cmovne %eax, %esi
callq __lll_unlock_wake
13: movq %r10, %rax
jmp 14b
91:
.LcleanupSTART2:
/* FUTEX_WAIT_REQUEUE_PI returned EAGAIN. We need to
call it again. */
movq 8(%rsp), %rdi
/* Get internal lock. */
movl $1, %esi
xorl %eax, %eax
LOCK
#if cond_lock == 0
cmpxchgl %esi, (%rdi)
#else
cmpxchgl %esi, cond_lock(%rdi)
#endif
jz 92f
#if cond_lock != 0
addq $cond_lock, %rdi
#endif
LP_OP(cmp) $-1, dep_mutex-cond_lock(%rdi)
movl $LLL_PRIVATE, %eax
movl $LLL_SHARED, %esi
cmovne %eax, %esi
callq __lll_lock_wait
#if cond_lock != 0
subq $cond_lock, %rdi
#endif
92:
/* Increment the cond_futex value again, so it can be used as a new
expected value. */
incl cond_futex(%rdi)
movl cond_futex(%rdi), %edx
/* Release internal lock. */
LOCK
#if cond_lock == 0
decl (%rdi)
#else
decl cond_lock(%rdi)
#endif
jz 93f
#if cond_lock != 0
addq $cond_lock, %rdi
#endif
LP_OP(cmp) $-1, dep_mutex-cond_lock(%rdi)
movl $LLL_PRIVATE, %eax
movl $LLL_SHARED, %esi
cmovne %eax, %esi
/* The call preserves %rdx. */
callq __lll_unlock_wake
#if cond_lock != 0
subq $cond_lock, %rdi
#endif
93:
/* Set the rest of SYS_futex args for FUTEX_WAIT_REQUEUE_PI. */
xorq %r10, %r10
mov dep_mutex(%rdi), %R8_LP
leaq cond_futex(%rdi), %rdi
jmp 90b
.LcleanupEND2:
.size __pthread_cond_wait, .-__pthread_cond_wait
versioned_symbol (libpthread, __pthread_cond_wait, pthread_cond_wait,
GLIBC_2_3_2)
.align 16
.type __condvar_cleanup1, @function
.globl __condvar_cleanup1
.hidden __condvar_cleanup1
__condvar_cleanup1:
/* Stack frame:
rsp + 32
+--------------------------+
rsp + 24 | unused |
+--------------------------+
rsp + 16 | mutex pointer |
+--------------------------+
rsp + 8 | condvar pointer |
+--------------------------+
rsp + 4 | old broadcast_seq value |
+--------------------------+
rsp + 0 | old cancellation mode |
+--------------------------+
*/
movq %rax, 24(%rsp)
/* Get internal lock. */
movq 8(%rsp), %rdi
movl $1, %esi
xorl %eax, %eax
LOCK
#if cond_lock == 0
cmpxchgl %esi, (%rdi)
#else
cmpxchgl %esi, cond_lock(%rdi)
#endif
jz 1f
#if cond_lock != 0
addq $cond_lock, %rdi
#endif
LP_OP(cmp) $-1, dep_mutex-cond_lock(%rdi)
movl $LLL_PRIVATE, %eax
movl $LLL_SHARED, %esi
cmovne %eax, %esi
callq __lll_lock_wait
#if cond_lock != 0
subq $cond_lock, %rdi
#endif
1: movl broadcast_seq(%rdi), %edx
cmpl 4(%rsp), %edx
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. */
movq total_seq(%rdi), %rax
cmpq wakeup_seq(%rdi), %rax
jbe 6f
incq wakeup_seq(%rdi)
incl cond_futex(%rdi)
6: incq woken_seq(%rdi)
3: subl $(1 << nwaiters_shift), cond_nwaiters(%rdi)
/* Wake up a thread which wants to destroy the condvar object. */
xorl %ecx, %ecx
cmpq $0xffffffffffffffff, total_seq(%rdi)
jne 4f
movl cond_nwaiters(%rdi), %eax
andl $~((1 << nwaiters_shift) - 1), %eax
jne 4f
LP_OP(cmp) $-1, dep_mutex(%rdi)
leaq cond_nwaiters(%rdi), %rdi
movl $1, %edx
#ifdef __ASSUME_PRIVATE_FUTEX
movl $FUTEX_WAKE, %eax
movl $(FUTEX_WAKE|FUTEX_PRIVATE_FLAG), %esi
cmove %eax, %esi
#else
movl $0, %eax
movl %fs:PRIVATE_FUTEX, %esi
cmove %eax, %esi
orl $FUTEX_WAKE, %esi
#endif
movl $SYS_futex, %eax
syscall
subq $cond_nwaiters, %rdi
movl $1, %ecx
4: LOCK
#if cond_lock == 0
decl (%rdi)
#else
decl cond_lock(%rdi)
#endif
je 2f
#if cond_lock != 0
addq $cond_lock, %rdi
#endif
LP_OP(cmp) $-1, dep_mutex-cond_lock(%rdi)
movl $LLL_PRIVATE, %eax
movl $LLL_SHARED, %esi
cmovne %eax, %esi
/* The call preserves %rcx. */
callq __lll_unlock_wake
/* Wake up all waiters to make sure no signal gets lost. */
2: testl %ecx, %ecx
jnz 5f
addq $cond_futex, %rdi
LP_OP(cmp) $-1, dep_mutex-cond_futex(%rdi)
movl $0x7fffffff, %edx
#ifdef __ASSUME_PRIVATE_FUTEX
movl $FUTEX_WAKE, %eax
movl $(FUTEX_WAKE|FUTEX_PRIVATE_FLAG), %esi
cmove %eax, %esi
#else
movl $0, %eax
movl %fs:PRIVATE_FUTEX, %esi
cmove %eax, %esi
orl $FUTEX_WAKE, %esi
#endif
movl $SYS_futex, %eax
syscall
5: movq 16(%rsp), %rdi
callq __pthread_mutex_cond_lock
movq 24(%rsp), %rdi
.LcallUR:
call _Unwind_Resume@PLT
hlt
.LENDCODE:
cfi_endproc
.size __condvar_cleanup1, .-__condvar_cleanup1
.section .gcc_except_table,"a",@progbits
.LexceptSTART:
.byte DW_EH_PE_omit # @LPStart format
.byte DW_EH_PE_omit # @TType format
.byte DW_EH_PE_uleb128 # call-site format
.uleb128 .Lcstend-.Lcstbegin
.Lcstbegin:
.uleb128 .LcleanupSTART-.LSTARTCODE
.uleb128 .LcleanupEND-.LcleanupSTART
.uleb128 __condvar_cleanup1-.LSTARTCODE
.uleb128 0
.uleb128 .LcleanupSTART2-.LSTARTCODE
.uleb128 .LcleanupEND2-.LcleanupSTART2
.uleb128 __condvar_cleanup1-.LSTARTCODE
.uleb128 0
.uleb128 .LcallUR-.LSTARTCODE
.uleb128 .LENDCODE-.LcallUR
.uleb128 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 LP_SIZE
.type DW.ref.__gcc_personality_v0, @object
.size DW.ref.__gcc_personality_v0, LP_SIZE
DW.ref.__gcc_personality_v0:
ASM_ADDR __gcc_personality_v0
#endif
|