On Wed, Jul 03, 2024 at 02:44:37PM +0200, Tim Wiederhake wrote:
`pthread_mutex_destroy`, `pthread_mutex_lock` and `pthread_mutex_unlock` return an error code that is currently ignored.
Add debug information if one of these operations failed, e.g. when there is an attempt to destroy a still locked mutex or unlock an already unlocked mutex. Both scenarios are considered undefined behavior.
Signed-off-by: Tim Wiederhake <twiederh@redhat.com> --- src/util/virthread.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-)
diff --git a/src/util/virthread.c b/src/util/virthread.c index 5422bb74fd..14116a2221 100644 --- a/src/util/virthread.c +++ b/src/util/virthread.c @@ -35,7 +35,10 @@
#include "viralloc.h" #include "virthreadjob.h" +#include "virlog.h"
+#define VIR_FROM_THIS VIR_FROM_THREAD +VIR_LOG_INIT("util.thread");
int virOnce(virOnceControl *once, virOnceFunc init) { @@ -83,17 +86,23 @@ int virMutexInitRecursive(virMutex *m)
void virMutexDestroy(virMutex *m) { - pthread_mutex_destroy(&m->lock); + if (pthread_mutex_destroy(&m->lock)) { + VIR_WARN("Failed to destroy mutex=%p", m); + } }
void virMutexLock(virMutex *m) { - pthread_mutex_lock(&m->lock); + if (pthread_mutex_lock(&m->lock)) { + VIR_WARN("Failed to lock mutex=%p", m); + } }
void virMutexUnlock(virMutex *m) { - pthread_mutex_unlock(&m->lock); + if (pthread_mutex_unlock(&m->lock)) { + VIR_WARN("Failed to unlock mutex=%p", m); + } }
I'd be surprised if these lock/unlock warnings ever trigger, since IIUC they would need us to be using an error checking mutex, not a regular mutex. IOW, aren't these just adding condition test overhead + unreachable code to the lock calls ? The 2nd patch shows failures in the destroy calls IIUC. With regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|