1 /* Copyright (C) 2002, 2003, 2004, 2005, 2007 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3 Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, write to the Free
17 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
21 #include <shlib-compat.h>
22 #include <lowlevellock.h>
23 #include <lowlevelcond.h>
24 #include <kernel-features.h>
25 #include <pthread-errnos.h>
30 /* int pthread_cond_signal (pthread_cond_t *cond) */
31 .globl __pthread_cond_signal
32 .type __pthread_cond_signal, @function
34 __pthread_cond_signal:
36 /* Get internal lock. */
44 cmpxchgl %esi, cond_lock(%rdi)
48 2: addq $cond_futex, %rdi
49 movq total_seq(%r8), %rcx
50 cmpq wakeup_seq(%r8), %rcx
53 /* Bump the wakeup number. */
54 addq $1, wakeup_seq(%r8)
57 /* Wake up one thread. */
58 cmpq $-1, dep_mutex(%r8)
60 #ifdef __ASSUME_PRIVATE_FUTEX
61 movl $FUTEX_WAKE_OP, %eax
62 movl $(FUTEX_WAKE_OP|FUTEX_PRIVATE_FLAG), %esi
66 movl %fs:PRIVATE_FUTEX, %esi
68 orl $FUTEX_WAKE_OP, %esi
75 movl $FUTEX_OP_CLEAR_WAKE_IF_GT_ONE, %r9d
80 /* For any kind of error, we try again with WAKE.
81 The general test also covers running on old kernels. */
88 7: /* %esi should be either FUTEX_WAKE_OP or
89 FUTEX_WAKE_OP|FUTEX_PRIVATE_FLAG from the previous syscall. */
90 xorl $(FUTEX_WAKE ^ FUTEX_WAKE_OP), %esi
92 /* %rdx should be 1 already from $FUTEX_WAKE_OP syscall.
108 /* Initial locking failed. */
111 addq $cond_lock, %rdi
113 cmpq $-1, dep_mutex-cond_lock(%rdi)
114 movl $LLL_PRIVATE, %eax
115 movl $LLL_SHARED, %esi
117 callq __lll_lock_wait
119 subq $cond_lock, %rdi
123 /* Unlock in loop requires wakeup. */
127 addq $cond_lock, %rdi
129 cmpq $-1, dep_mutex-cond_lock(%rdi)
130 movl $LLL_PRIVATE, %eax
131 movl $LLL_SHARED, %esi
133 callq __lll_unlock_wake
135 .size __pthread_cond_signal, .-__pthread_cond_signal
136 versioned_symbol (libpthread, __pthread_cond_signal, pthread_cond_signal,