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|
/* Copyright (C) 2002-2015 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-pi-defines.h>
#include <pthread-errnos.h>
#include <stap-probe.h>
#include <kernel-features.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
pushq %r12
cfi_adjust_cfa_offset(8)
cfi_rel_offset(%r12, 0)
pushq %r13
cfi_adjust_cfa_offset(8)
cfi_rel_offset(%r13, 0)
pushq %r14
cfi_adjust_cfa_offset(8)
cfi_rel_offset(%r14, 0)
pushq %r15
cfi_adjust_cfa_offset(8)
cfi_rel_offset(%r15, 0)
#define FRAME_SIZE (32+8)
subq $FRAME_SIZE, %rsp
cfi_adjust_cfa_offset(FRAME_SIZE)
cfi_remember_state
LIBC_PROBE (cond_timedwait, 3, %rdi, %rsi, %rdx)
cmpq $1000000000, 8(%rdx)
movl $EINVAL, %eax
jae 48f
/* Stack frame:
rsp + 48
+--------------------------+
rsp + 32 | timeout value |
+--------------------------+
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)
movq %rdx, %r13
je 22f
mov %RSI_LP, dep_mutex(%rdi)
22:
xorb %r15b, %r15b
/* Get internal lock. */
movl $1, %esi
xorl %eax, %eax
LOCK
#if cond_lock == 0
cmpxchgl %esi, (%rdi)
#else
cmpxchgl %esi, cond_lock(%rdi)
#endif
jnz 31f
/* Unlock the mutex. */
32: movq 16(%rsp), %rdi
xorl %esi, %esi
callq __pthread_mutex_unlock_usercnt
testl %eax, %eax
jne 46f
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)
cmpq $0, (%r13)
movq $-ETIMEDOUT, %r14
js 36f
38: movl cond_futex(%rdi), %r12d
/* Unlock. */
LOCK
#if cond_lock == 0
decl (%rdi)
#else
decl cond_lock(%rdi)
#endif
jne 33f
.LcleanupSTART1:
34: callq __pthread_enable_asynccancel
movl %eax, (%rsp)
movq %r13, %r10
movl $FUTEX_WAIT_BITSET, %esi
LP_OP(cmp) $-1, dep_mutex(%rdi)
je 60f
mov dep_mutex(%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
movl $(FUTEX_WAIT_REQUEUE_PI|FUTEX_PRIVATE_FLAG), %esi
xorl %eax, %eax
/* The following only works like this because we only support
two clocks, represented using a single bit. */
testl $1, cond_nwaiters(%rdi)
movl $FUTEX_CLOCK_REALTIME, %edx
cmove %edx, %eax
orl %eax, %esi
movq %r12, %rdx
addq $cond_futex, %rdi
movl $SYS_futex, %eax
syscall
cmpl $0, %eax
sete %r15b
#ifdef __ASSUME_REQUEUE_PI
jmp 62f
#else
je 62f
/* When a futex syscall with FUTEX_WAIT_REQUEUE_PI returns
successfully, it has already locked the mutex for us and the
pi_flag (%r15b) is set to denote that fact. However, if another
thread changed the futex value before we entered the wait, the
syscall may return an EAGAIN and the mutex is not locked. We go
ahead with a success anyway since later we look at the pi_flag to
decide if we got the mutex or not. The sequence numbers then make
sure that only one of the threads actually wake up. We retry using
normal FUTEX_WAIT only if the kernel returned ENOSYS, since normal
and PI futexes don't mix.
Note that we don't check for EAGAIN specifically; we assume that the
only other error the futex function could return is EAGAIN (barring
the ETIMEOUT of course, for the timeout case in futex) since
anything else would mean an error in our function. It is too
expensive to do that check for every call (which is quite common in
case of a large number of threads), so it has been skipped. */
cmpl $-ENOSYS, %eax
jne 62f
subq $cond_futex, %rdi
#endif
61: movl $(FUTEX_WAIT_BITSET|FUTEX_PRIVATE_FLAG), %esi
60: xorb %r15b, %r15b
xorl %eax, %eax
/* The following only works like this because we only support
two clocks, represented using a single bit. */
testl $1, cond_nwaiters(%rdi)
movl $FUTEX_CLOCK_REALTIME, %edx
movl $0xffffffff, %r9d
cmove %edx, %eax
orl %eax, %esi
movq %r12, %rdx
addq $cond_futex, %rdi
movl $SYS_futex, %eax
syscall
62: movq %rax, %r14
movl (%rsp), %edi
callq __pthread_disable_asynccancel
.LcleanupEND1:
/* 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
jne 35f
36: movl broadcast_seq(%rdi), %edx
movq woken_seq(%rdi), %rax
movq wakeup_seq(%rdi), %r9
cmpl 4(%rsp), %edx
jne 53f
cmpq 24(%rsp), %r9
jbe 45f
cmpq %rax, %r9
ja 39f
45: cmpq $-ETIMEDOUT, %r14
je 99f
/* We need to go back to futex_wait. If we're using requeue_pi, then
release the mutex we had acquired and go back. */
test %r15b, %r15b
jz 38b
/* Adjust the mutex values first and then unlock it. The unlock
should always succeed or else the kernel did not lock the
mutex correctly. */
movq %r8, %rdi
callq __pthread_mutex_cond_lock_adjust
xorl %esi, %esi
callq __pthread_mutex_unlock_usercnt
/* Reload cond_var. */
movq 8(%rsp), %rdi
jmp 38b
99: incq wakeup_seq(%rdi)
incl cond_futex(%rdi)
movl $ETIMEDOUT, %r14d
jmp 44f
53: xorq %r14, %r14
jmp 54f
39: xorq %r14, %r14
44: incq woken_seq(%rdi)
54: subl $(1 << nwaiters_shift), cond_nwaiters(%rdi)
/* Wake up a thread which wants to destroy the condvar object. */
cmpq $0xffffffffffffffff, total_seq(%rdi)
jne 55f
movl cond_nwaiters(%rdi), %eax
andl $~((1 << nwaiters_shift) - 1), %eax
jne 55f
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
55: LOCK
#if cond_lock == 0
decl (%rdi)
#else
decl cond_lock(%rdi)
#endif
jne 40f
/* If requeue_pi is used the kernel performs the locking of the
mutex. */
41: movq 16(%rsp), %rdi
testb %r15b, %r15b
jnz 64f
callq __pthread_mutex_cond_lock
63: testq %rax, %rax
cmoveq %r14, %rax
48: addq $FRAME_SIZE, %rsp
cfi_adjust_cfa_offset(-FRAME_SIZE)
popq %r15
cfi_adjust_cfa_offset(-8)
cfi_restore(%r15)
popq %r14
cfi_adjust_cfa_offset(-8)
cfi_restore(%r14)
popq %r13
cfi_adjust_cfa_offset(-8)
cfi_restore(%r13)
popq %r12
cfi_adjust_cfa_offset(-8)
cfi_restore(%r12)
retq
cfi_restore_state
64: callq __pthread_mutex_cond_lock_adjust
movq %r14, %rax
jmp 48b
/* Initial locking failed. */
31:
#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 32b
/* Unlock in loop requires wakeup. */
33:
#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 34b
/* Locking in loop failed. */
35:
#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 36b
/* Unlock after loop requires wakeup. */
40:
#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 41b
/* The initial unlocking of the mutex failed. */
46: movq 8(%rsp), %rdi
movq %rax, (%rsp)
LOCK
#if cond_lock == 0
decl (%rdi)
#else
decl cond_lock(%rdi)
#endif
jne 47f
#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
47: movq (%rsp), %rax
jmp 48b
.size __pthread_cond_timedwait, .-__pthread_cond_timedwait
versioned_symbol (libpthread, __pthread_cond_timedwait, pthread_cond_timedwait,
GLIBC_2_3_2)
.align 16
.type __condvar_cleanup2, @function
__condvar_cleanup2:
/* Stack frame:
rsp + 72
+--------------------------+
rsp + 64 | %r12 |
+--------------------------+
rsp + 56 | %r13 |
+--------------------------+
rsp + 48 | %r14 |
+--------------------------+
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. */
xorq %r12, %r12
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, %r12d
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
callq __lll_unlock_wake
/* Wake up all waiters to make sure no signal gets lost. */
2: testq %r12, %r12
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
/* Lock the mutex only if we don't own it already. This only happens
in case of PI mutexes, if we got cancelled after a successful
return of the futex syscall and before disabling async
cancellation. */
5: movq 16(%rsp), %rdi
movl MUTEX_KIND(%rdi), %eax
andl $(ROBUST_BIT|PI_BIT), %eax
cmpl $PI_BIT, %eax
jne 7f
movl (%rdi), %eax
andl $TID_MASK, %eax
cmpl %eax, %fs:TID
jne 7f
/* We managed to get the lock. Fix it up before returning. */
callq __pthread_mutex_cond_lock_adjust
jmp 8f
7: callq __pthread_mutex_cond_lock
8: movq 24(%rsp), %rdi
movq FRAME_SIZE(%rsp), %r15
movq FRAME_SIZE+8(%rsp), %r14
movq FRAME_SIZE+16(%rsp), %r13
movq FRAME_SIZE+24(%rsp), %r12
.LcallUR:
call _Unwind_Resume@PLT
hlt
.LENDCODE:
cfi_endproc
.size __condvar_cleanup2, .-__condvar_cleanup2
.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 .LcleanupSTART1-.LSTARTCODE
.uleb128 .LcleanupEND1-.LcleanupSTART1
.uleb128 __condvar_cleanup2-.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
|