* See the COPYING file in the top-level directory.
*
*/
-#include <stdlib.h>
-#include <stdio.h>
-#include <errno.h>
-#include <time.h>
-#include <signal.h>
-#include <stdint.h>
-#include <string.h>
-#include <limits.h>
-#include <unistd.h>
-#include <sys/time.h>
+#include "qemu/osdep.h"
#ifdef __linux__
#include <sys/syscall.h>
#include <linux/futex.h>
void qemu_mutex_init(QemuMutex *mutex)
{
int err;
- pthread_mutexattr_t mutexattr;
- pthread_mutexattr_init(&mutexattr);
- pthread_mutexattr_settype(&mutexattr, PTHREAD_MUTEX_ERRORCHECK);
- err = pthread_mutex_init(&mutex->lock, &mutexattr);
- pthread_mutexattr_destroy(&mutexattr);
+ err = pthread_mutex_init(&mutex->lock, NULL);
if (err)
error_exit(err, __func__);
}
static inline void futex_wait(QemuEvent *ev, unsigned val)
{
- futex(ev, FUTEX_WAIT, (int) val, NULL, NULL, 0);
+ while (futex(ev, FUTEX_WAIT, (int) val, NULL, NULL, 0)) {
+ switch (errno) {
+ case EWOULDBLOCK:
+ return;
+ case EINTR:
+ break; /* get out of switch and retry */
+ default:
+ abort();
+ }
+ }
}
#else
static inline void futex_wake(QemuEvent *ev, int n)
void qemu_event_set(QemuEvent *ev)
{
- if (atomic_mb_read(&ev->value) != EV_SET) {
+ /* qemu_event_set has release semantics, but because it *loads*
+ * ev->value we need a full memory barrier here.
+ */
+ smp_mb();
+ if (atomic_read(&ev->value) != EV_SET) {
if (atomic_xchg(&ev->value, EV_SET) == EV_BUSY) {
/* There were waiters, wake them up. */
futex_wake(ev, INT_MAX);
void qemu_event_reset(QemuEvent *ev)
{
- if (atomic_mb_read(&ev->value) == EV_SET) {
+ unsigned value;
+
+ value = atomic_read(&ev->value);
+ smp_mb_acquire();
+ if (value == EV_SET) {
/*
* If there was a concurrent reset (or even reset+wait),
* do nothing. Otherwise change EV_SET->EV_FREE.
{
unsigned value;
- value = atomic_mb_read(&ev->value);
+ value = atomic_read(&ev->value);
+ smp_mb_acquire();
if (value != EV_SET) {
if (value == EV_FREE) {
/*
* Leave the event reset and tell qemu_event_set that there
* are waiters. No need to retry, because there cannot be
- * a concurent busy->free transition. After the CAS, the
+ * a concurrent busy->free transition. After the CAS, the
* event will be either set or busy.
*/
if (atomic_cmpxchg(&ev->value, EV_FREE, EV_BUSY) == EV_SET) {