qemu-thread: Assert locks are initialized before using
Not all platforms check whether a lock is initialized before used. In
particular Linux seems to be more permissive than OSX.
Check initialization state explicitly in our code to catch such bugs
earlier.
Signed-off-by: Fam Zheng <famz@redhat.com>
Message-Id: <20170704122325.25634-1-famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff --git a/util/qemu-thread-posix.c b/util/qemu-thread-posix.c
index eacd99e..4e95d27 100644
--- a/util/qemu-thread-posix.c
+++ b/util/qemu-thread-posix.c
@@ -43,12 +43,15 @@
err = pthread_mutex_init(&mutex->lock, NULL);
if (err)
error_exit(err, __func__);
+ mutex->initialized = true;
}
void qemu_mutex_destroy(QemuMutex *mutex)
{
int err;
+ assert(mutex->initialized);
+ mutex->initialized = false;
err = pthread_mutex_destroy(&mutex->lock);
if (err)
error_exit(err, __func__);
@@ -58,6 +61,7 @@
{
int err;
+ assert(mutex->initialized);
err = pthread_mutex_lock(&mutex->lock);
if (err)
error_exit(err, __func__);
@@ -69,6 +73,7 @@
{
int err;
+ assert(mutex->initialized);
err = pthread_mutex_trylock(&mutex->lock);
if (err == 0) {
trace_qemu_mutex_locked(mutex);
@@ -84,6 +89,7 @@
{
int err;
+ assert(mutex->initialized);
trace_qemu_mutex_unlocked(mutex);
err = pthread_mutex_unlock(&mutex->lock);
if (err)
@@ -102,6 +108,7 @@
if (err) {
error_exit(err, __func__);
}
+ mutex->initialized = true;
}
void qemu_cond_init(QemuCond *cond)
@@ -111,12 +118,15 @@
err = pthread_cond_init(&cond->cond, NULL);
if (err)
error_exit(err, __func__);
+ cond->initialized = true;
}
void qemu_cond_destroy(QemuCond *cond)
{
int err;
+ assert(cond->initialized);
+ cond->initialized = false;
err = pthread_cond_destroy(&cond->cond);
if (err)
error_exit(err, __func__);
@@ -126,6 +136,7 @@
{
int err;
+ assert(cond->initialized);
err = pthread_cond_signal(&cond->cond);
if (err)
error_exit(err, __func__);
@@ -135,6 +146,7 @@
{
int err;
+ assert(cond->initialized);
err = pthread_cond_broadcast(&cond->cond);
if (err)
error_exit(err, __func__);
@@ -144,6 +156,7 @@
{
int err;
+ assert(cond->initialized);
trace_qemu_mutex_unlocked(mutex);
err = pthread_cond_wait(&cond->cond, &mutex->lock);
trace_qemu_mutex_locked(mutex);
@@ -174,12 +187,15 @@
error_exit(errno, __func__);
}
#endif
+ sem->initialized = true;
}
void qemu_sem_destroy(QemuSemaphore *sem)
{
int rc;
+ assert(sem->initialized);
+ sem->initialized = false;
#if defined(__APPLE__) || defined(__NetBSD__)
rc = pthread_cond_destroy(&sem->cond);
if (rc < 0) {
@@ -201,6 +217,7 @@
{
int rc;
+ assert(sem->initialized);
#if defined(__APPLE__) || defined(__NetBSD__)
pthread_mutex_lock(&sem->lock);
if (sem->count == UINT_MAX) {
@@ -238,6 +255,7 @@
int rc;
struct timespec ts;
+ assert(sem->initialized);
#if defined(__APPLE__) || defined(__NetBSD__)
rc = 0;
compute_abs_deadline(&ts, ms);
@@ -285,6 +303,7 @@
{
int rc;
+ assert(sem->initialized);
#if defined(__APPLE__) || defined(__NetBSD__)
pthread_mutex_lock(&sem->lock);
while (sem->count == 0) {
@@ -310,6 +329,7 @@
#else
static inline void qemu_futex_wake(QemuEvent *ev, int n)
{
+ assert(ev->initialized);
pthread_mutex_lock(&ev->lock);
if (n == 1) {
pthread_cond_signal(&ev->cond);
@@ -321,6 +341,7 @@
static inline void qemu_futex_wait(QemuEvent *ev, unsigned val)
{
+ assert(ev->initialized);
pthread_mutex_lock(&ev->lock);
if (ev->value == val) {
pthread_cond_wait(&ev->cond, &ev->lock);
@@ -355,10 +376,13 @@
#endif
ev->value = (init ? EV_SET : EV_FREE);
+ ev->initialized = true;
}
void qemu_event_destroy(QemuEvent *ev)
{
+ assert(ev->initialized);
+ ev->initialized = false;
#ifndef __linux__
pthread_mutex_destroy(&ev->lock);
pthread_cond_destroy(&ev->cond);
@@ -370,6 +394,7 @@
/* qemu_event_set has release semantics, but because it *loads*
* ev->value we need a full memory barrier here.
*/
+ assert(ev->initialized);
smp_mb();
if (atomic_read(&ev->value) != EV_SET) {
if (atomic_xchg(&ev->value, EV_SET) == EV_BUSY) {
@@ -383,6 +408,7 @@
{
unsigned value;
+ assert(ev->initialized);
value = atomic_read(&ev->value);
smp_mb_acquire();
if (value == EV_SET) {
@@ -398,6 +424,7 @@
{
unsigned value;
+ assert(ev->initialized);
value = atomic_read(&ev->value);
smp_mb_acquire();
if (value != EV_SET) {
