1 /*
2 * Copyright (c) 2003 Fabrice Bellard
3 *
4 * This library is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Lesser General Public
6 * License as published by the Free Software Foundation; either
7 * version 2 of the License, or (at your option) any later version.
8 *
9 * This library is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Lesser General Public License for more details.
13 *
14 * You should have received a copy of the GNU Lesser General Public
15 * License along with this library; if not, see <http://www.gnu.org/licenses/>
16 */
17
18 /* configure guarantees us that we have pthreads on any host except
19 * mingw32, which doesn't support any of the user-only targets.
20 * So we can simply assume we have pthread mutexes here.
21 */
22 #if defined(CONFIG_USER_ONLY)
23
24 #include <pthread.h>
25 #define spin_lock pthread_mutex_lock
26 #define spin_unlock pthread_mutex_unlock
27 #define spinlock_t pthread_mutex_t
28 #define SPIN_LOCK_UNLOCKED PTHREAD_MUTEX_INITIALIZER
29
30 #else
31
32 /* Empty implementations, on the theory that system mode emulation
33 * is single-threaded. This means that these functions should only
34 * be used from code run in the TCG cpu thread, and cannot protect
35 * data structures which might also be accessed from the IO thread
36 * or from signal handlers.
37 */
38 typedef int spinlock_t;
39 #define SPIN_LOCK_UNLOCKED 0
40
spin_lock(spinlock_t * lock)41 static inline void spin_lock(spinlock_t *lock)
42 {
43 }
44
spin_unlock(spinlock_t * lock)45 static inline void spin_unlock(spinlock_t *lock)
46 {
47 }
48
49 #endif
50