glibc/sysdeps/htl/pt-barrier-wait.c

71 lines
1.9 KiB
C

/* pthread_barrier_wait. Generic version.
Copyright (C) 2002-2024 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 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
<https://www.gnu.org/licenses/>. */
#include <pthread.h>
#include <assert.h>
#include <pt-internal.h>
int
pthread_barrier_wait (pthread_barrier_t *barrier)
{
__pthread_spin_wait (&barrier->__lock);
if (--barrier->__pending == 0)
{
barrier->__pending = barrier->__count;
if (barrier->__count == 1)
__pthread_spin_unlock (&barrier->__lock);
else
{
struct __pthread *wakeup;
unsigned n = 0;
__pthread_queue_iterate (barrier->__queue, wakeup)
n++;
{
struct __pthread *wakeups[n];
unsigned i = 0;
__pthread_dequeuing_iterate (barrier->__queue, wakeup)
wakeups[i++] = wakeup;
barrier->__queue = NULL;
__pthread_spin_unlock (&barrier->__lock);
for (i = 0; i < n; i++)
__pthread_wakeup (wakeups[i]);
}
}
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;
}
}