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/* Copyright (C) 2002, 2003, 2004, 2005 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, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#include <sysdep.h>
#include <lowlevelcond.h>
#include <pthread-errnos.h>
#include <tcb-offsets.h>
#ifdef UP
# define LOCK
#else
# define LOCK lock
#endif
#define FUTEX_WAIT 0
#define FUTEX_WAKE 1
/* For the calculation see asm/vsyscall.h. */
#define VSYSCALL_ADDR_vgettimeofday 0xffffffffff600000
.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:
pushq %r12
.Lpush_r12:
pushq %r13
.Lpush_r13:
pushq %r14
.Lpush_r14:
#define FRAME_SIZE 80
subq $FRAME_SIZE, %rsp
.Lsubq:
cmpq $1000000000, 8(%rdx)
movl $EINVAL, %eax
jae 18f
/* Stack frame:
rsp + 80
+--------------------------+
rsp + 48 | cleanup buffer |
+--------------------------+
rsp + 40 | old wake_seq value |
+--------------------------+
rsp + 24 | timeout value |
+--------------------------+
rsp + 16 | mutex pointer |
+--------------------------+
rsp + 8 | condvar pointer |
+--------------------------+
rsp + 4 | old broadcast_seq value |
+--------------------------+
rsp + 0 | old cancellation mode |
+--------------------------+
*/
cmpq $-1, dep_mutex(%rdi)
/* Prepare structure passed to cancellation handler. */
movq %rdi, 8(%rsp)
movq %rsi, 16(%rsp)
movq %rdx, %r13
je 22f
movq %rsi, dep_mutex(%rdi)
/* Get internal lock. */
22: movl $1, %esi
xorl %eax, %eax
LOCK
#if cond_lock == 0
cmpxchgl %esi, (%rdi)
#else
cmpxchgl %esi, cond_lock(%rdi)
#endif
jnz 1f
/* Unlock the mutex. */
2: movq 16(%rsp), %rdi
xorl %esi, %esi
callq __pthread_mutex_unlock_usercnt
testl %eax, %eax
jne 16f
movq 8(%rsp), %rdi
incq total_seq(%rdi)
incl cond_futex(%rdi)
addl $(1 << clock_bits), cond_nwaiters(%rdi)
/* Install cancellation handler. */
#ifdef __PIC__
leaq __condvar_cleanup(%rip), %rsi
#else
leaq __condvar_cleanup, %rsi
#endif
leaq 48(%rsp), %rdi
movq %rsp, %rdx
callq __pthread_cleanup_push
/* Get and store current wakeup_seq value. */
movq 8(%rsp), %rdi
movq wakeup_seq(%rdi), %r9
movl broadcast_seq(%rdi), %edx
movq %r9, 40(%rsp)
movl %edx, 4(%rsp)
/* Get the current time. */
8:
#ifdef __NR_clock_gettime
/* Get the clock number. Note that the field in the condvar
structure stores the number minus 1. */
movq 8(%rsp), %rdi
movl cond_nwaiters(%rdi), %edi
andl $((1 << clock_bits) - 1), %edi
/* Only clocks 0 and 1 are allowed so far. Both are handled in the
kernel. */
leaq 24(%rsp), %rsi
movl $__NR_clock_gettime, %eax
syscall
# ifndef __ASSUME_POSIX_TIMERS
cmpq $-ENOSYS, %rax
je 19f
# endif
/* Compute relative timeout. */
movq (%r13), %rcx
movq 8(%r13), %rdx
subq 24(%rsp), %rcx
subq 32(%rsp), %rdx
#else
leaq 24(%rsp), %rdi
xorl %esi, %esi
movq $VSYSCALL_ADDR_vgettimeofday, %rax
callq *%rax
/* Compute relative timeout. */
movq 32(%rsp), %rax
movl $1000, %edx
mul %rdx /* Milli seconds to nano seconds. */
movq (%r13), %rcx
movq 8(%r13), %rdx
subq 24(%rsp), %rcx
subq %rax, %rdx
#endif
jns 12f
addq $1000000000, %rdx
decq %rcx
12: testq %rcx, %rcx
movq 8(%rsp), %rdi
movq $-ETIMEDOUT, %r14
js 6f
/* Store relative timeout. */
21: movq %rcx, 24(%rsp)
movq %rdx, 32(%rsp)
movl cond_futex(%rdi), %r12d
/* Unlock. */
LOCK
#if cond_lock == 0
decl (%rdi)
#else
decl cond_lock(%rdi)
#endif
jne 3f
4: callq __pthread_enable_asynccancel
movl %eax, (%rsp)
leaq 24(%rsp), %r10
#if FUTEX_WAIT == 0
xorl %esi, %esi
#else
movl $FUTEX_WAIT, %esi
#endif
movq %r12, %rdx
addq $cond_futex, %rdi
movl $SYS_futex, %eax
syscall
movq %rax, %r14
movl (%rsp), %edi
callq __pthread_disable_asynccancel
/* 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 5f
6: movl broadcast_seq(%rdi), %edx
movq woken_seq(%rdi), %rax
movq wakeup_seq(%rdi), %r9
cmpl 4(%rsp), %edx
jne 23f
cmpq 40(%rsp), %r9
jbe 15f
cmpq %rax, %r9
ja 9f
15: cmpq $-ETIMEDOUT, %r14
jne 8b
13: incq wakeup_seq(%rdi)
incl cond_futex(%rdi)
movl $ETIMEDOUT, %r14d
jmp 14f
23: xorq %r14, %r14
jmp 24f
9: xorq %r14, %r14
14: incq woken_seq(%rdi)
24: subl $(1 << clock_bits), cond_nwaiters(%rdi)
/* Wake up a thread which wants to destroy the condvar object. */
cmpq $0xffffffffffffffff, total_seq(%rdi)
jne 25f
movl cond_nwaiters(%rdi), %eax
andl $~((1 << clock_bits) - 1), %eax
jne 25f
addq $cond_nwaiters, %rdi
movl $SYS_futex, %eax
movl $FUTEX_WAKE, %esi
movl $1, %edx
syscall
subq $cond_nwaiters, %rdi
25: LOCK
#if cond_lock == 0
decl (%rdi)
#else
decl cond_lock(%rdi)
#endif
jne 10f
/* Remove cancellation handler. */
11: movq 48+CLEANUP_PREV(%rsp), %rdx
movq %rdx, %fs:CLEANUP
movq 16(%rsp), %rdi
callq __pthread_mutex_cond_lock
testq %rax, %rax
cmoveq %r14, %rax
18: addq $FRAME_SIZE, %rsp
.Laddq:
popq %r14
.Lpop_r14:
popq %r13
.Lpop_r13:
popq %r12
.Lpop_r12:
retq
/* Initial locking failed. */
1:
.LSbl1:
#if cond_lock != 0
addq $cond_lock, %rdi
#endif
callq __lll_mutex_lock_wait
jmp 2b
/* Unlock in loop requires wakeup. */
3:
#if cond_lock != 0
addq $cond_lock, %rdi
#endif
callq __lll_mutex_unlock_wake
jmp 4b
/* Locking in loop failed. */
5:
#if cond_lock != 0
addq $cond_lock, %rdi
#endif
callq __lll_mutex_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
callq __lll_mutex_unlock_wake
jmp 11b
/* The initial unlocking of the mutex failed. */
16: movq 8(%rsp), %rdi
movq %rax, (%rsp)
LOCK
#if cond_lock == 0
decl (%rdi)
#else
decl cond_lock(%rdi)
#endif
jne 17f
#if cond_lock != 0
addq $cond_lock, %rdi
#endif
callq __lll_mutex_unlock_wake
17: movq (%rsp), %rax
jmp 18b
#if defined __NR_clock_gettime && !defined __ASSUME_POSIX_TIMERS
/* clock_gettime not available. */
19: leaq 24(%rsp), %rdi
xorl %esi, %esi
movq $VSYSCALL_ADDR_vgettimeofday, %rax
callq *%rax
/* Compute relative timeout. */
movq 32(%rsp), %rax
movl $1000, %edx
mul %rdx /* Milli seconds to nano seconds. */
movq (%r13), %rcx
movq 8(%r13), %rdx
subq 24(%rsp), %rcx
subq %rax, %rdx
jns 20f
addq $1000000000, %rdx
decq %rcx
20: testq %rcx, %rcx
movq 8(%rsp), %rdi
movq $-ETIMEDOUT, %r14
js 6b
jmp 21b
#endif
.LENDCODE:
.size __pthread_cond_timedwait, .-__pthread_cond_timedwait
weak_alias(__pthread_cond_timedwait, pthread_cond_timedwait)
.section .eh_frame,"a",@progbits
.LSTARTFRAME:
.long .LENDCIE-.LSTARTCIE # Length of the CIE.
.LSTARTCIE:
.long 0 # CIE ID.
.byte 1 # Version number.
#ifdef SHARED
.string "zR" # NUL-terminated augmentation
# string.
#else
.ascii "\0" # NUL-terminated augmentation
# string.
#endif
.uleb128 1 # Code alignment factor.
.sleb128 -8 # Data alignment factor.
.byte 16 # Return address register
# column.
#ifdef SHARED
.uleb128 1 # Augmentation value length.
.byte 0x1b # Encoding: DW_EH_PE_pcrel
# + DW_EH_PE_sdata4.
#endif
.byte 0x0c # DW_CFA_def_cfa
.uleb128 7
.uleb128 8
.byte 0x90 # DW_CFA_offset, column 0x8
.uleb128 1
.align 8
.LENDCIE:
.long .LENDFDE-.LSTARTFDE # Length of the FDE.
.LSTARTFDE:
.long .LSTARTFDE-.LSTARTFRAME # CIE pointer.
#ifdef SHARED
.long .LSTARTCODE-. # PC-relative start address
# of the code
#else
.long .LSTARTCODE # Start address of the code.
#endif
.long .LENDCODE-.LSTARTCODE # Length of the code.
#ifdef SHARED
.uleb128 0 # No augmentation data.
#endif
.byte 0x40+.Lpush_r12-.LSTARTCODE # DW_CFA_advance_loc+N
.byte 14 # DW_CFA_def_cfa_offset
.uleb128 16
.byte 0x8c # DW_CFA_offset %r12
.uleb128 2
.byte 0x40+.Lpush_r13-.Lpush_r12 # DW_CFA_advance_loc+N
.byte 14 # DW_CFA_def_cfa_offset
.uleb128 24
.byte 0x8d # DW_CFA_offset %r13
.uleb128 3
.byte 0x40+.Lpush_r14-.Lpush_r13 # DW_CFA_advance_loc+N
.byte 14 # DW_CFA_def_cfa_offset
.uleb128 32
.byte 0x84 # DW_CFA_offset %r14
.uleb128 4
.byte 0x40+.Lsubq-.Lpush_r14 # DW_CFA_advance_loc+N
.byte 14 # DW_CFA_def_cfa_offset
.uleb128 32+FRAME_SIZE
.byte 3 # DW_CFA_advance_loc2
.2byte .Laddq-.Lsubq
.byte 14 # DW_CFA_def_cfa_offset
.uleb128 32
.byte 0x40+.Lpop_r14-.Laddq # DW_CFA_advance_loc+N
.byte 14 # DW_CFA_def_cfa_offset
.uleb128 24
.byte 0xce # DW_CFA_restore %r14
.byte 0x40+.Lpop_r13-.Lpop_r14 # DW_CFA_advance_loc+N
.byte 14 # DW_CFA_def_cfa_offset
.uleb128 16
.byte 0xcd # DW_CFA_restore %r13
.byte 0x40+.Lpop_r12-.Lpop_r13 # DW_CFA_advance_loc+N
.byte 14 # DW_CFA_def_cfa_offset
.uleb128 8
.byte 0xcc # DW_CFA_restore %r12
.byte 0x40+.LSbl1-.Lpop_r12 # DW_CFA_advance_loc+N
.byte 14 # DW_CFA_def_cfa_offset
.uleb128 32+FRAME_SIZE
.byte 0x8c # DW_CFA_offset %r12
.uleb128 2
.byte 0x8d # DW_CFA_offset %r13
.uleb128 3
.byte 0x84 # DW_CFA_offset %r14
.uleb128 4
.align 8
.LENDFDE:
|