/* Forward referenced functions */
static void *watchdog_thread(void *arg);
+static void wd_lock();
+static void wd_unlock();
/* Static globals */
-static pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;
-static pthread_cond_t timer = PTHREAD_COND_INITIALIZER;
-static bool quit;
+static bool quit = false;;
static bool wd_is_init = false;
+static brwlock_t lock; /* watchdog lock */
-/* Forward referenced callback functions */
static pthread_t wd_tid;
-
-/* Static globals */
static dlist *wd_queue;
static dlist *wd_inactive;
{
int stat;
watchdog_t *dummy = NULL;
+ int errstat;
if (wd_is_init) {
return 0;
}
Dmsg0(200, "Initialising NicB-hacked watchdog thread\n");
watchdog_time = time(NULL);
- quit = false;
+ if ((errstat=rwl_init(&lock)) != 0) {
+ Emsg1(M_ABORT, 0, _("Unable to initialize watchdog lock. ERR=%s\n"),
+ strerror(errstat));
+ }
wd_queue = new dlist(wd_queue, &dummy->link);
wd_inactive = new dlist(wd_inactive, &dummy->link);
return 0;
}
- Dmsg0(200, "Sending stop signal to NicB-hacked watchdog thread\n");
- P(mutex);
- quit = true;
- stat = pthread_cond_signal(&timer);
- V(mutex);
-
+ quit = true; /* notify watchdog thread to stop */
wd_is_init = false;
stat = pthread_join(wd_tid, NULL);
}
free(p);
}
+
delete wd_inactive;
wd_inactive = NULL;
+ rwl_destroy(&lock);
return stat;
}
if (!wd_is_init) {
start_watchdog();
- if (!wd_is_init) {
- Emsg0(M_ABORT, 0, "BUG! new_watchdog called before start_watchdog\n");
- }
}
if (wd == NULL) {
Emsg1(M_ABORT, 0, "BUG! Watchdog %p has zero interval\n", wd);
}
- P(mutex);
+ wd_lock();
wd->next_fire = watchdog_time + wd->interval;
wd_queue->append(wd);
Dmsg3(200, "Registered watchdog %p, interval %d%s\n",
wd, wd->interval, wd->one_shot ? " one shot" : "");
- V(mutex);
+ wd_unlock();
return false;
}
Emsg0(M_ABORT, 0, "BUG! unregister_watchdog called before start_watchdog\n");
}
- P(mutex);
+ wd_lock();
ret = unregister_watchdog_unlocked(wd);
- V(mutex);
+ wd_unlock();
return ret;
}
{
Dmsg0(200, "NicB-reworked watchdog thread entered\n");
- while (true) {
+ while (!quit) {
watchdog_t *p;
- P(mutex);
- if (quit) {
- V(mutex);
- break;
- }
-
+ /*
+ * We lock the jcr chain here because a good number of the
+ * callback routines lock the jcr chain. We need to lock
+ * it here *before* the watchdog lock because the SD message
+ * thread first locks the jcr chain, then when closing the
+ * job locks the watchdog chain. If the two thread do not
+ * lock in the same order, we get a deadlock -- each holds
+ * the other's needed lock.
+ */
+ lock_jcr_chain();
+ wd_lock();
watchdog_time = time(NULL);
foreach_dlist(p, wd_queue) {
}
}
}
- V(mutex);
+ wd_unlock();
+ unlock_jcr_chain();
bmicrosleep(SLEEP_TIME, 0);
}
Dmsg0(200, "NicB-reworked watchdog thread exited\n");
return NULL;
}
+
+/*
+ * Watchdog lock, this can be called multiple times by the same
+ * thread without blocking, but must be unlocked the number of
+ * times it was locked.
+ */
+static void wd_lock()
+{
+ int errstat;
+ if ((errstat=rwl_writelock(&lock)) != 0) {
+ Emsg1(M_ABORT, 0, "rwl_writelock failure. ERR=%s\n",
+ strerror(errstat));
+ }
+}
+
+/*
+ * Unlock the watchdog. This can be called multiple times by the
+ * same thread up to the number of times that thread called
+ * wd_ lock()/
+ */
+static void wd_unlock()
+{
+ int errstat;
+ if ((errstat=rwl_writeunlock(&lock)) != 0) {
+ Emsg1(M_ABORT, 0, "rwl_writeunlock failure. ERR=%s\n",
+ strerror(errstat));
+ }
+}