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|
/* Copyright (C) 2002-2017 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 <pthread-errnos.h>
#include <kernel-features.h>
#include <lowlevellock.h>
#include <stap-probe.h>
.text
#ifdef __ASSUME_PRIVATE_FUTEX
# define LOAD_PRIVATE_FUTEX_WAIT(reg) \
movl $(FUTEX_WAIT | FUTEX_PRIVATE_FLAG), reg
# define LOAD_PRIVATE_FUTEX_WAKE(reg) \
movl $(FUTEX_WAKE | FUTEX_PRIVATE_FLAG), reg
# define LOAD_FUTEX_WAIT(reg) \
xorl $(FUTEX_WAIT | FUTEX_PRIVATE_FLAG), reg
# define LOAD_FUTEX_WAIT_ABS(reg) \
xorl $(FUTEX_WAIT_BITSET | FUTEX_PRIVATE_FLAG | FUTEX_CLOCK_REALTIME), reg
# define LOAD_FUTEX_WAKE(reg) \
xorl $(FUTEX_WAKE | FUTEX_PRIVATE_FLAG), reg
#else
# if FUTEX_WAIT == 0
# define LOAD_PRIVATE_FUTEX_WAIT(reg) \
movl %gs:PRIVATE_FUTEX, reg
# else
# define LOAD_PRIVATE_FUTEX_WAIT(reg) \
movl %gs:PRIVATE_FUTEX, reg ; \
orl $FUTEX_WAIT, reg
# endif
# define LOAD_PRIVATE_FUTEX_WAKE(reg) \
movl %gs:PRIVATE_FUTEX, reg ; \
orl $FUTEX_WAKE, reg
# if FUTEX_WAIT == 0
# define LOAD_FUTEX_WAIT(reg) \
xorl $FUTEX_PRIVATE_FLAG, reg ; \
andl %gs:PRIVATE_FUTEX, reg
# else
# define LOAD_FUTEX_WAIT(reg) \
xorl $FUTEX_PRIVATE_FLAG, reg ; \
andl %gs:PRIVATE_FUTEX, reg ; \
orl $FUTEX_WAIT, reg
# endif
# define LOAD_FUTEX_WAIT_ABS(reg) \
xorl $FUTEX_PRIVATE_FLAG, reg ; \
andl %gs:PRIVATE_FUTEX, reg ; \
orl $FUTEX_WAIT_BITSET | FUTEX_CLOCK_REALTIME, reg
# define LOAD_FUTEX_WAKE(reg) \
xorl $FUTEX_PRIVATE_FLAG, reg ; \
andl %gs:PRIVATE_FUTEX, reg ; \
orl $FUTEX_WAKE, reg
#endif
.globl __lll_lock_wait_private
.type __lll_lock_wait_private,@function
.hidden __lll_lock_wait_private
.align 16
__lll_lock_wait_private:
cfi_startproc
pushl %edx
cfi_adjust_cfa_offset(4)
pushl %ebx
cfi_adjust_cfa_offset(4)
pushl %esi
cfi_adjust_cfa_offset(4)
cfi_offset(%edx, -8)
cfi_offset(%ebx, -12)
cfi_offset(%esi, -16)
movl $2, %edx
movl %ecx, %ebx
xorl %esi, %esi /* No timeout. */
LOAD_PRIVATE_FUTEX_WAIT (%ecx)
cmpl %edx, %eax /* NB: %edx == 2 */
jne 2f
1: LIBC_PROBE (lll_lock_wait_private, 1, %ebx)
movl $SYS_futex, %eax
ENTER_KERNEL
2: movl %edx, %eax
xchgl %eax, (%ebx) /* NB: lock is implied */
testl %eax, %eax
jnz 1b
popl %esi
cfi_adjust_cfa_offset(-4)
cfi_restore(%esi)
popl %ebx
cfi_adjust_cfa_offset(-4)
cfi_restore(%ebx)
popl %edx
cfi_adjust_cfa_offset(-4)
cfi_restore(%edx)
ret
cfi_endproc
.size __lll_lock_wait_private,.-__lll_lock_wait_private
#if !IS_IN (libc)
.globl __lll_lock_wait
.type __lll_lock_wait,@function
.hidden __lll_lock_wait
.align 16
__lll_lock_wait:
cfi_startproc
pushl %edx
cfi_adjust_cfa_offset(4)
pushl %ebx
cfi_adjust_cfa_offset(4)
pushl %esi
cfi_adjust_cfa_offset(4)
cfi_offset(%edx, -8)
cfi_offset(%ebx, -12)
cfi_offset(%esi, -16)
movl %edx, %ebx
movl $2, %edx
xorl %esi, %esi /* No timeout. */
LOAD_FUTEX_WAIT (%ecx)
cmpl %edx, %eax /* NB: %edx == 2 */
jne 2f
1: movl $SYS_futex, %eax
ENTER_KERNEL
2: movl %edx, %eax
xchgl %eax, (%ebx) /* NB: lock is implied */
testl %eax, %eax
jnz 1b
popl %esi
cfi_adjust_cfa_offset(-4)
cfi_restore(%esi)
popl %ebx
cfi_adjust_cfa_offset(-4)
cfi_restore(%ebx)
popl %edx
cfi_adjust_cfa_offset(-4)
cfi_restore(%edx)
ret
cfi_endproc
.size __lll_lock_wait,.-__lll_lock_wait
/* %ecx: futex
%esi: flags
%edx: timeout
%eax: futex value
*/
.globl __lll_timedlock_wait
.type __lll_timedlock_wait,@function
.hidden __lll_timedlock_wait
.align 16
__lll_timedlock_wait:
cfi_startproc
pushl %ebp
cfi_adjust_cfa_offset(4)
cfi_rel_offset(%ebp, 0)
pushl %ebx
cfi_adjust_cfa_offset(4)
cfi_rel_offset(%ebx, 0)
# ifndef __ASSUME_FUTEX_CLOCK_REALTIME
# ifdef PIC
LOAD_PIC_REG (bx)
cmpl $0, __have_futex_clock_realtime@GOTOFF(%ebx)
# else
cmpl $0, __have_futex_clock_realtime
# endif
je .Lreltmo
# endif
cmpl $0, (%edx)
js 8f
movl %ecx, %ebx
movl %esi, %ecx
movl %edx, %esi
movl $0xffffffff, %ebp
LOAD_FUTEX_WAIT_ABS (%ecx)
movl $2, %edx
cmpl %edx, %eax
jne 2f
1: movl $SYS_futex, %eax
movl $2, %edx
ENTER_KERNEL
2: xchgl %edx, (%ebx) /* NB: lock is implied */
testl %edx, %edx
jz 3f
cmpl $-ETIMEDOUT, %eax
je 4f
cmpl $-EINVAL, %eax
jne 1b
4: movl %eax, %edx
negl %edx
3: movl %edx, %eax
7: popl %ebx
cfi_adjust_cfa_offset(-4)
cfi_restore(%ebx)
popl %ebp
cfi_adjust_cfa_offset(-4)
cfi_restore(%ebp)
ret
8: movl $ETIMEDOUT, %eax
jmp 7b
# ifndef __ASSUME_FUTEX_CLOCK_REALTIME
.Lreltmo:
/* Check for a valid timeout value. */
cmpl $1000000000, 4(%edx)
jae 3f
pushl %esi
cfi_adjust_cfa_offset(4)
cfi_rel_offset(%esi, 0)
pushl %edi
cfi_adjust_cfa_offset(4)
cfi_rel_offset(%edi, 0)
/* Stack frame for the timespec and timeval structs. */
subl $8, %esp
cfi_adjust_cfa_offset(8)
movl %ecx, %ebp
movl %edx, %edi
movl $2, %edx
xchgl %edx, (%ebp)
test %edx, %edx
je 6f
1:
/* Get current time. */
movl %esp, %ebx
xorl %ecx, %ecx
movl $__NR_gettimeofday, %eax
ENTER_KERNEL
/* Compute relative timeout. */
movl 4(%esp), %eax
movl $1000, %edx
mul %edx /* Milli seconds to nano seconds. */
movl (%edi), %ecx
movl 4(%edi), %edx
subl (%esp), %ecx
subl %eax, %edx
jns 4f
addl $1000000000, %edx
subl $1, %ecx
4: testl %ecx, %ecx
js 2f /* Time is already up. */
/* Store relative timeout. */
movl %ecx, (%esp)
movl %edx, 4(%esp)
/* Futex call. */
movl %ebp, %ebx
movl $2, %edx
movl %esp, %esi
movl 16(%esp), %ecx
LOAD_FUTEX_WAIT (%ecx)
movl $SYS_futex, %eax
ENTER_KERNEL
/* NB: %edx == 2 */
xchgl %edx, (%ebp)
testl %edx, %edx
je 6f
cmpl $-ETIMEDOUT, %eax
jne 1b
2: movl $ETIMEDOUT, %edx
6: addl $8, %esp
cfi_adjust_cfa_offset(-8)
popl %edi
cfi_adjust_cfa_offset(-4)
cfi_restore(%edi)
popl %esi
cfi_adjust_cfa_offset(-4)
cfi_restore(%esi)
7: popl %ebx
cfi_adjust_cfa_offset(-4)
cfi_restore(%ebx)
popl %ebp
cfi_adjust_cfa_offset(-4)
cfi_restore(%ebp)
movl %edx, %eax
ret
3: movl $EINVAL, %edx
jmp 7b
# endif
cfi_endproc
.size __lll_timedlock_wait,.-__lll_timedlock_wait
#endif
.globl __lll_unlock_wake_private
.type __lll_unlock_wake_private,@function
.hidden __lll_unlock_wake_private
.align 16
__lll_unlock_wake_private:
cfi_startproc
pushl %ebx
cfi_adjust_cfa_offset(4)
pushl %ecx
cfi_adjust_cfa_offset(4)
pushl %edx
cfi_adjust_cfa_offset(4)
cfi_offset(%ebx, -8)
cfi_offset(%ecx, -12)
cfi_offset(%edx, -16)
movl %eax, %ebx
movl $0, (%eax)
LOAD_PRIVATE_FUTEX_WAKE (%ecx)
movl $1, %edx /* Wake one thread. */
movl $SYS_futex, %eax
ENTER_KERNEL
popl %edx
cfi_adjust_cfa_offset(-4)
cfi_restore(%edx)
popl %ecx
cfi_adjust_cfa_offset(-4)
cfi_restore(%ecx)
popl %ebx
cfi_adjust_cfa_offset(-4)
cfi_restore(%ebx)
ret
cfi_endproc
.size __lll_unlock_wake_private,.-__lll_unlock_wake_private
#if !IS_IN (libc)
.globl __lll_unlock_wake
.type __lll_unlock_wake,@function
.hidden __lll_unlock_wake
.align 16
__lll_unlock_wake:
cfi_startproc
pushl %ebx
cfi_adjust_cfa_offset(4)
pushl %ecx
cfi_adjust_cfa_offset(4)
pushl %edx
cfi_adjust_cfa_offset(4)
cfi_offset(%ebx, -8)
cfi_offset(%ecx, -12)
cfi_offset(%edx, -16)
movl %eax, %ebx
movl $0, (%eax)
LOAD_FUTEX_WAKE (%ecx)
movl $1, %edx /* Wake one thread. */
movl $SYS_futex, %eax
ENTER_KERNEL
popl %edx
cfi_adjust_cfa_offset(-4)
cfi_restore(%edx)
popl %ecx
cfi_adjust_cfa_offset(-4)
cfi_restore(%ecx)
popl %ebx
cfi_adjust_cfa_offset(-4)
cfi_restore(%ebx)
ret
cfi_endproc
.size __lll_unlock_wake,.-__lll_unlock_wake
.globl __lll_timedwait_tid
.type __lll_timedwait_tid,@function
.hidden __lll_timedwait_tid
.align 16
__lll_timedwait_tid:
pushl %edi
pushl %esi
pushl %ebx
pushl %ebp
movl %eax, %ebp
movl %edx, %edi
subl $8, %esp
/* Get current time. */
2: movl %esp, %ebx
xorl %ecx, %ecx
movl $__NR_gettimeofday, %eax
ENTER_KERNEL
/* Compute relative timeout. */
movl 4(%esp), %eax
movl $1000, %edx
mul %edx /* Milli seconds to nano seconds. */
movl (%edi), %ecx
movl 4(%edi), %edx
subl (%esp), %ecx
subl %eax, %edx
jns 5f
addl $1000000000, %edx
subl $1, %ecx
5: testl %ecx, %ecx
js 6f /* Time is already up. */
movl %ecx, (%esp) /* Store relative timeout. */
movl %edx, 4(%esp)
movl (%ebp), %edx
testl %edx, %edx
jz 4f
movl %esp, %esi
/* XXX The kernel so far uses global futex for the wakeup at
all times. */
xorl %ecx, %ecx /* movl $FUTEX_WAIT, %ecx */
movl %ebp, %ebx
movl $SYS_futex, %eax
ENTER_KERNEL
cmpl $0, (%ebx)
jne 1f
4: xorl %eax, %eax
3: addl $8, %esp
popl %ebp
popl %ebx
popl %esi
popl %edi
ret
1: cmpl $-ETIMEDOUT, %eax
jne 2b
6: movl $ETIMEDOUT, %eax
jmp 3b
.size __lll_timedwait_tid,.-__lll_timedwait_tid
#endif
|
