2 * Copyright (c) 2003 David Xu <davidxu@freebsd.org>
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * $FreeBSD: src/lib/libpthread/thread/thr_barrier.c,v 1.1 2003/09/04 14:06:43 davidxu Exp $
29 #include "namespace.h"
30 #include <machine/tls.h>
34 #include "un-namespace.h"
36 #include "thr_private.h"
39 _pthread_barrier_destroy(pthread_barrier_t *barrier)
41 pthread_barrier_t bar;
43 if (barrier == NULL || *barrier == NULL)
47 if (bar->b_waiters > 0)
55 _pthread_barrier_init(pthread_barrier_t *barrier,
56 const pthread_barrierattr_t *attr __unused, unsigned count)
58 pthread_barrier_t bar;
60 if (barrier == NULL || count == 0 || count > INT_MAX)
63 bar = malloc(sizeof(struct pthread_barrier));
67 _thr_umtx_init(&bar->b_lock);
77 _pthread_barrier_wait(pthread_barrier_t *barrier)
79 struct pthread *curthread;
80 pthread_barrier_t bar;
84 if (barrier == NULL || *barrier == NULL)
88 curthread = tls_get_curthread();
89 THR_UMTX_LOCK(curthread, &bar->b_lock);
90 if (++bar->b_waiters == bar->b_count) {
91 /* Current thread is lastest thread */
94 _thr_umtx_wake(&bar->b_cycle, bar->b_count);
95 THR_UMTX_UNLOCK(curthread, &bar->b_lock);
96 ret = PTHREAD_BARRIER_SERIAL_THREAD;
99 THR_UMTX_UNLOCK(curthread, &bar->b_lock);
101 _thr_umtx_wait(&bar->b_cycle, cycle, NULL, 0);
102 /* test cycle to avoid bogus wakeup */
103 } while (cycle == bar->b_cycle);
109 __strong_reference(_pthread_barrier_init, pthread_barrier_init);
110 __strong_reference(_pthread_barrier_wait, pthread_barrier_wait);
111 __strong_reference(_pthread_barrier_destroy, pthread_barrier_destroy);