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/* pthread_barrier_wait. Generic version.
Copyright (C) 2002 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 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
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If not,
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#include <pthread.h>
#include <assert.h>
#include <pt-internal.h>
int
pthread_barrier_wait (pthread_barrier_t *barrier)
{
__pthread_spin_lock (&barrier->lock);
if (-- barrier->pending == 0)
{
barrier->pending = barrier->count;
if (barrier->count > 1)
{
struct __pthread *wakeup;
wakeup = barrier->queue;
barrier->queue = NULL;
__pthread_spin_unlock (&barrier->lock);
/* We can safely walk the list of waiting threads without
holding the lock since it is decoupled from the barrier
variable now. */
__pthread_dequeuing_iterate (wakeup, wakeup)
__pthread_wakeup (wakeup);
}
return PTHREAD_BARRIER_SERIAL_THREAD;
}
else
{
struct __pthread *self = _pthread_self ();
/* Add ourselves to the list of waiters. */
__pthread_enqueue (&barrier->queue, self);
__pthread_spin_unlock (&barrier->lock);
__pthread_block (self);
return 0;
}
}
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