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/* Copyright (C) 2003-2013 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Martin Schwidefsky <schwidefsky@de.ibm.com>, 2003.
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 <endian.h>
#include <errno.h>
#include <sysdep.h>
#include <lowlevellock.h>
#include <pthread.h>
#include <pthreadP.h>
#include <stap-probe.h>
#include <shlib-compat.h>
#include <kernel-features.h>
int
__pthread_cond_broadcast (cond)
pthread_cond_t *cond;
{
LIBC_PROBE (cond_broadcast, 1, cond);
int pshared = (cond->__data.__mutex == (void *) ~0l)
? LLL_SHARED : LLL_PRIVATE;
/* Make sure we are alone. */
lll_lock (cond->__data.__lock, pshared);
/* Are there any waiters to be woken? */
if (cond->__data.__total_seq > cond->__data.__wakeup_seq)
{
/* Yes. Mark them all as woken. */
cond->__data.__wakeup_seq = cond->__data.__total_seq;
cond->__data.__woken_seq = cond->__data.__total_seq;
cond->__data.__futex = (unsigned int) cond->__data.__total_seq * 2;
int futex_val = cond->__data.__futex;
/* Signal that a broadcast happened. */
++cond->__data.__broadcast_seq;
/* We are done. */
lll_unlock (cond->__data.__lock, pshared);
/* Do not use requeue for pshared condvars. */
if (cond->__data.__mutex == (void *) ~0l)
goto wake_all;
/* Wake everybody. */
pthread_mutex_t *mut = (pthread_mutex_t *) cond->__data.__mutex;
/* XXX: Kernel so far doesn't support requeue to PI futex. */
/* XXX: Kernel so far can only requeue to the same type of futex,
in this case private (we don't requeue for pshared condvars). */
if (__builtin_expect (mut->__data.__kind
& (PTHREAD_MUTEX_PRIO_INHERIT_NP
| PTHREAD_MUTEX_PSHARED_BIT), 0))
goto wake_all;
/* lll_futex_requeue returns 0 for success and non-zero
for errors. */
if (__builtin_expect (lll_futex_requeue (&cond->__data.__futex, 1,
INT_MAX, &mut->__data.__lock,
futex_val, LLL_PRIVATE), 0))
{
/* The requeue functionality is not available. */
wake_all:
lll_futex_wake (&cond->__data.__futex, INT_MAX, pshared);
}
/* That's all. */
return 0;
}
/* We are done. */
lll_unlock (cond->__data.__lock, pshared);
return 0;
}
versioned_symbol (libpthread, __pthread_cond_broadcast, pthread_cond_broadcast,
GLIBC_2_3_2);
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