/* * Copyright (c) 2003 Fabrice Bellard * * This library 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 of the License, or (at your option) any later version. * * This library 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 this library; if not, see */ /* configure guarantees us that we have pthreads on any host except * mingw32, which doesn't support any of the user-only targets. * So we can simply assume we have pthread mutexes here. */ #ifndef QEMU_EXEC_SPINLOCK_H #define QEMU_EXEC_SPINLOCK_H #if defined(CONFIG_USER_ONLY) #include #define spin_lock pthread_mutex_lock #define spin_unlock pthread_mutex_unlock #define spinlock_t pthread_mutex_t #define SPIN_LOCK_UNLOCKED PTHREAD_MUTEX_INITIALIZER #else /* Empty implementations, on the theory that system mode emulation * is single-threaded. This means that these functions should only * be used from code run in the TCG cpu thread, and cannot protect * data structures which might also be accessed from the IO thread * or from signal handlers. */ typedef int spinlock_t; #define SPIN_LOCK_UNLOCKED 0 static inline void spin_lock(spinlock_t *lock) { } static inline void spin_unlock(spinlock_t *lock) { } #endif #endif