#ifndef QEMU_THREAD_H
#define QEMU_THREAD_H
#include "qemu/processor.h"
#include "qemu/atomic.h"
typedef struct QemuMutex QemuMutex;
typedef struct QemuCond QemuCond;
typedef struct QemuSemaphore QemuSemaphore;
typedef struct QemuEvent QemuEvent;
typedef struct QemuLockCnt QemuLockCnt;
typedef struct QemuThread QemuThread;
#ifdef _WIN32
#include "qemu/thread-win32.h"
#else
#include "qemu/thread-posix.h"
#endif
#define QEMU_THREAD_JOINABLE 0
#define QEMU_THREAD_DETACHED 1
void qemu_mutex_init(QemuMutex *mutex);
void qemu_mutex_destroy(QemuMutex *mutex);
void qemu_mutex_lock(QemuMutex *mutex);
int qemu_mutex_trylock(QemuMutex *mutex);
void qemu_mutex_unlock(QemuMutex *mutex);
/* Prototypes for other functions are in thread-posix.h/thread-win32.h. */
void qemu_rec_mutex_init(QemuRecMutex *mutex);
void qemu_cond_init(QemuCond *cond);
void qemu_cond_destroy(QemuCond *cond);
/*
* IMPORTANT: The implementation does not guarantee that pthread_cond_signal
* and pthread_cond_broadcast can be called except while the same mutex is
* held as in the corresponding pthread_cond_wait calls!
*/
void qemu_cond_signal(QemuCond *cond);
void qemu_cond_broadcast(QemuCond *cond);
void qemu_cond_wait(QemuCond *cond, QemuMutex *mutex);
void qemu_sem_init(QemuSemaphore *sem, int init);
void qemu_sem_post(QemuSemaphore *sem);
void qemu_sem_wait(QemuSemaphore *sem);
int qemu_sem_timedwait(QemuSemaphore *sem, int ms);
void qemu_sem_destroy(QemuSemaphore *sem);
void qemu_event_init(QemuEvent *ev, bool init);
void qemu_event_set(QemuEvent *ev);
void qemu_event_reset(QemuEvent *ev);
void qemu_event_wait(QemuEvent *ev);
void qemu_event_destroy(QemuEvent *ev);
void qemu_thread_create(QemuThread *thread, const char *name,
void *(*start_routine)(void *),
void *arg, int mode);
void *qemu_thread_join(QemuThread *thread);
void qemu_thread_get_self(QemuThread *thread);
bool qemu_thread_is_self(QemuThread *thread);
void qemu_thread_exit(void *retval);
void qemu_thread_naming(bool enable);
struct Notifier;
void qemu_thread_atexit_add(struct Notifier *notifier);
void qemu_thread_atexit_remove(struct Notifier *notifier);
typedef struct QemuSpin {
int value;
} QemuSpin;
static inline void qemu_spin_init(QemuSpin *spin)
{
__sync_lock_release(&spin->value);
}
static inline void qemu_spin_lock(QemuSpin *spin)
{
while (unlikely(__sync_lock_test_and_set(&spin->value, true))) {
while (atomic_read(&spin->value)) {
cpu_relax();
}
}
}
static inline bool qemu_spin_trylock(QemuSpin *spin)
{
return __sync_lock_test_and_set(&spin->value, true);
}
static inline bool qemu_spin_locked(QemuSpin *spin)
{
return atomic_read(&spin->value);
}
static inline void qemu_spin_unlock(QemuSpin *spin)
{
__sync_lock_release(&spin->value);
}
struct QemuLockCnt {
#ifndef CONFIG_LINUX
QemuMutex mutex;
#endif
unsigned count;
};
/**
* qemu_lockcnt_init: initialize a QemuLockcnt
* @lockcnt: the lockcnt to initialize
*
* Initialize lockcnt's counter to zero and prepare its mutex
* for usage.
*/
void qemu_lockcnt_init(QemuLockCnt *lockcnt);
/**
* qemu_lockcnt_destroy: destroy a QemuLockcnt
* @lockcnt: the lockcnt to destruct
*
* Destroy lockcnt's mutex.
*/
void qemu_lockcnt_destroy(QemuLockCnt *lockcnt);
/**
* qemu_lockcnt_inc: increment a QemuLockCnt's counter
* @lockcnt: the lockcnt to operate on
*
* If the lockcnt's count is zero, wait for critical sections
* to finish and increment lockcnt's count to 1. If the count
* is not zero, just increment it.
*
* Because this function can wait on the mutex, it must not be
* called while the lockcnt's mutex is held by the current thread.
* For the same reason, qemu_lockcnt_inc can also contribute to
* AB-BA deadlocks. This is a sample deadlock scenario:
*
* thread 1 thread 2
* -------------------------------------------------------
* qemu_lockcnt_lock(&lc1);
* qemu_lockcnt_lock(&lc2);
* qemu_lockcnt_inc(&lc2);
* qemu_lockcnt_inc(&lc1);
*/
void qemu_lockcnt_inc(QemuLockCnt *lockcnt);
/**
* qemu_lockcnt_dec: decrement a QemuLockCnt's counter
* @lockcnt: the lockcnt to operate on
*/
void qemu_lockcnt_dec(QemuLockCnt *lockcnt);
/**
* qemu_lockcnt_dec_and_lock: decrement a QemuLockCnt's counter and
* possibly lock it.
* @lockcnt: the lockcnt to operate on
*
* Decrement lockcnt's count. If the new count is zero, lock
* the mutex and return true. Otherwise, return false.
*/
bool qemu_lockcnt_dec_and_lock(QemuLockCnt *lockcnt);
/**
* qemu_lockcnt_dec_if_lock: possibly decrement a QemuLockCnt's counter and
* lock it.
* @lockcnt: the lockcnt to operate on
*
* If the count is 1, decrement the count to zero, lock
* the mutex and return true. Otherwise, return false.
*/
bool qemu_lockcnt_dec_if_lock(QemuLockCnt *lockcnt);
/**
* qemu_lockcnt_lock: lock a QemuLockCnt's mutex.
* @lockcnt: the lockcnt to operate on
*
* Remember that concurrent visits are not blocked unless the count is
* also zero. You can use qemu_lockcnt_count to check for this inside a
* critical section.
*/
void qemu_lockcnt_lock(QemuLockCnt *lockcnt);
/**
* qemu_lockcnt_unlock: release a QemuLockCnt's mutex.
* @lockcnt: the lockcnt to operate on.
*/
void qemu_lockcnt_unlock(QemuLockCnt *lockcnt);
/**
* qemu_lockcnt_inc_and_unlock: combined unlock/increment on a QemuLockCnt.
* @lockcnt: the lockcnt to operate on.
*
* This is the same as
*
* qemu_lockcnt_unlock(lockcnt);
* qemu_lockcnt_inc(lockcnt);
*
* but more efficient.
*/
void qemu_lockcnt_inc_and_unlock(QemuLockCnt *lockcnt);
/**
* qemu_lockcnt_count: query a LockCnt's count.
* @lockcnt: the lockcnt to query.
*
* Note that the count can change at any time. Still, while the
* lockcnt is locked, one can usefully check whether the count
* is non-zero.
*/
unsigned qemu_lockcnt_count(QemuLockCnt *lockcnt);
#endif
