|
145
|
1 /* Copyright (C) 2005-2020 Free Software Foundation, Inc.
|
|
0
|
2 Contributed by Richard Henderson <rth@redhat.com>.
|
|
|
3
|
|
111
|
4 This file is part of the GNU Offloading and Multi Processing Library
|
|
|
5 (libgomp).
|
|
0
|
6
|
|
|
7 Libgomp is free software; you can redistribute it and/or modify it
|
|
|
8 under the terms of the GNU General Public License as published by
|
|
|
9 the Free Software Foundation; either version 3, or (at your option)
|
|
|
10 any later version.
|
|
|
11
|
|
|
12 Libgomp is distributed in the hope that it will be useful, but WITHOUT ANY
|
|
|
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
|
|
|
14 FOR A PARTICULAR PURPOSE. See the GNU General Public License for
|
|
|
15 more details.
|
|
|
16
|
|
|
17 Under Section 7 of GPL version 3, you are granted additional
|
|
|
18 permissions described in the GCC Runtime Library Exception, version
|
|
|
19 3.1, as published by the Free Software Foundation.
|
|
|
20
|
|
|
21 You should have received a copy of the GNU General Public License and
|
|
|
22 a copy of the GCC Runtime Library Exception along with this program;
|
|
|
23 see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
|
|
|
24 <http://www.gnu.org/licenses/>. */
|
|
|
25
|
|
|
26 /* This is a Linux specific implementation of a mutex synchronization
|
|
|
27 mechanism for libgomp. This type is private to the library. This
|
|
|
28 implementation uses atomic instructions and the futex syscall. */
|
|
|
29
|
|
|
30 #ifndef GOMP_MUTEX_H
|
|
|
31 #define GOMP_MUTEX_H 1
|
|
|
32
|
|
|
33 typedef int gomp_mutex_t;
|
|
|
34
|
|
|
35 #define GOMP_MUTEX_INIT_0 1
|
|
|
36
|
|
111
|
37 extern void gomp_mutex_lock_slow (gomp_mutex_t *mutex, int);
|
|
|
38 extern void gomp_mutex_unlock_slow (gomp_mutex_t *mutex);
|
|
|
39
|
|
|
40 static inline void
|
|
|
41 gomp_mutex_init (gomp_mutex_t *mutex)
|
|
0
|
42 {
|
|
|
43 *mutex = 0;
|
|
|
44 }
|
|
|
45
|
|
111
|
46 static inline void
|
|
|
47 gomp_mutex_destroy (gomp_mutex_t *mutex)
|
|
0
|
48 {
|
|
|
49 }
|
|
|
50
|
|
111
|
51 static inline void
|
|
|
52 gomp_mutex_lock (gomp_mutex_t *mutex)
|
|
|
53 {
|
|
|
54 int oldval = 0;
|
|
|
55 if (!__atomic_compare_exchange_n (mutex, &oldval, 1, false,
|
|
|
56 MEMMODEL_ACQUIRE, MEMMODEL_RELAXED))
|
|
|
57 gomp_mutex_lock_slow (mutex, oldval);
|
|
|
58 }
|
|
|
59
|
|
|
60 static inline void
|
|
|
61 gomp_mutex_unlock (gomp_mutex_t *mutex)
|
|
|
62 {
|
|
|
63 int wait = __atomic_exchange_n (mutex, 0, MEMMODEL_RELEASE);
|
|
|
64 if (__builtin_expect (wait < 0, 0))
|
|
|
65 gomp_mutex_unlock_slow (mutex);
|
|
|
66 }
|
|
0
|
67 #endif /* GOMP_MUTEX_H */
|
