gcc/libgomp/config/linux/sem.h
2009-04-09 17:00:19 +02:00

58 lines
1.9 KiB
C

/* Copyright (C) 2005, 2009 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 General Public License as published by
the Free Software Foundation; either version 3, 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 General Public License for
more details.
Under Section 7 of GPL version 3, you are granted additional
permissions described in the GCC Runtime Library Exception, version
3.1, as published by the Free Software Foundation.
You should have received a copy of the GNU General Public License and
a copy of the GCC Runtime Library Exception along with this program;
see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
<http://www.gnu.org/licenses/>. */
/* This is a Linux specific implementation of a semaphore synchronization
mechanism for libgomp. This type is private to the library. This
implementation uses atomic instructions and the futex syscall. */
#ifndef GOMP_SEM_H
#define GOMP_SEM_H 1
typedef int gomp_sem_t;
static inline void gomp_sem_init (gomp_sem_t *sem, int value)
{
*sem = value;
}
extern void gomp_sem_wait_slow (gomp_sem_t *);
static inline void gomp_sem_wait (gomp_sem_t *sem)
{
if (!__sync_bool_compare_and_swap (sem, 1, 0))
gomp_sem_wait_slow (sem);
}
extern void gomp_sem_post_slow (gomp_sem_t *);
static inline void gomp_sem_post (gomp_sem_t *sem)
{
if (!__sync_bool_compare_and_swap (sem, 0, 1))
gomp_sem_post_slow (sem);
}
static inline void gomp_sem_destroy (gomp_sem_t *sem)
{
}
#endif /* GOMP_SEM_H */