diff options
Diffstat (limited to 'libgomp/config/posix/bar.c')
-rw-r--r-- | libgomp/config/posix/bar.c | 111 |
1 files changed, 111 insertions, 0 deletions
diff --git a/libgomp/config/posix/bar.c b/libgomp/config/posix/bar.c new file mode 100644 index 0000000..7972161 --- /dev/null +++ b/libgomp/config/posix/bar.c @@ -0,0 +1,111 @@ +/* Copyright (C) 2005 Free Software Foundation, Inc. + Contributed by Richard Henderson <rth@redhat.com>. + + This file is part of the GNU OpenMP Library (libgomp). + + Libgomp 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. + + Libgomp 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 libgomp; see the file COPYING.LIB. If not, write to the + Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, + MA 02110-1301, USA. */ + +/* As a special exception, if you link this library with other files, some + of which are compiled with GCC, to produce an executable, this library + does not by itself cause the resulting executable to be covered by the + GNU General Public License. This exception does not however invalidate + any other reasons why the executable file might be covered by the GNU + General Public License. */ + +/* This is the default implementation of a barrier synchronization mechanism + for libgomp. This type is private to the library. Note that we rely on + being able to adjust the barrier count while threads are blocked, so the + POSIX pthread_barrier_t won't work. */ + +#include "libgomp.h" + + +void +gomp_barrier_init (gomp_barrier_t *bar, unsigned count) +{ + gomp_mutex_init (&bar->mutex1); +#ifndef HAVE_SYNC_BUILTINS + gomp_mutex_init (&bar->mutex2); +#endif + gomp_sem_init (&bar->sem1, 0); + gomp_sem_init (&bar->sem2, 0); + bar->total = count; + bar->arrived = 0; +} + +void +gomp_barrier_destroy (gomp_barrier_t *bar) +{ + /* Before destroying, make sure all threads have left the barrier. */ + gomp_mutex_lock (&bar->mutex1); + gomp_mutex_unlock (&bar->mutex1); + + gomp_mutex_destroy (&bar->mutex1); +#ifndef HAVE_SYNC_BUILTINS + gomp_mutex_destroy (&bar->mutex2); +#endif + gomp_sem_destroy (&bar->sem1); + gomp_sem_destroy (&bar->sem2); +} + +void +gomp_barrier_reinit (gomp_barrier_t *bar, unsigned count) +{ + gomp_mutex_lock (&bar->mutex1); + bar->total = count; + gomp_mutex_unlock (&bar->mutex1); +} + +void +gomp_barrier_wait_end (gomp_barrier_t *bar, bool last) +{ + unsigned int n; + + if (last) + { + n = --bar->arrived; + if (n > 0) + { + do + gomp_sem_post (&bar->sem1); + while (--n != 0); + gomp_sem_wait (&bar->sem2); + } + gomp_mutex_unlock (&bar->mutex1); + } + else + { + gomp_mutex_unlock (&bar->mutex1); + gomp_sem_wait (&bar->sem1); + +#ifdef HAVE_SYNC_BUILTINS + n = __sync_add_and_fetch (&bar->arrived, -1); +#else + gomp_mutex_lock (&bar->mutex2); + n = --bar->arrived; + gomp_mutex_unlock (&bar->mutex2); +#endif + + if (n == 0) + gomp_sem_post (&bar->sem2); + } +} + +void +gomp_barrier_wait (gomp_barrier_t *barrier) +{ + gomp_barrier_wait_end (barrier, gomp_barrier_wait_start (barrier)); +} |