| /* 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 a Linux specific implementation of a mutex synchronization |
| mechanism for libgomp. This type is private to the library. This |
| implementation uses atomic instructions and the futex syscall. */ |
| |
| #ifndef GOMP_MUTEX_H |
| #define GOMP_MUTEX_H 1 |
| |
| typedef int gomp_mutex_t; |
| |
| #define GOMP_MUTEX_INIT_0 1 |
| |
| static inline void gomp_mutex_init (gomp_mutex_t *mutex) |
| { |
| *mutex = 0; |
| } |
| |
| extern void gomp_mutex_lock_slow (gomp_mutex_t *mutex); |
| static inline void gomp_mutex_lock (gomp_mutex_t *mutex) |
| { |
| if (!__sync_bool_compare_and_swap (mutex, 0, 1)) |
| gomp_mutex_lock_slow (mutex); |
| } |
| |
| extern void gomp_mutex_unlock_slow (gomp_mutex_t *mutex); |
| static inline void gomp_mutex_unlock (gomp_mutex_t *mutex) |
| { |
| int val = __sync_lock_test_and_set (mutex, 0); |
| if (__builtin_expect (val > 1, 0)) |
| gomp_mutex_unlock_slow (mutex); |
| } |
| |
| static inline void gomp_mutex_destroy (gomp_mutex_t *mutex) |
| { |
| } |
| |
| #endif /* GOMP_MUTEX_H */ |