/* Runs approximately every COVERAGE_CLEAR_INTERVAL amount of time to
* synchronize per-thread counters with global counters. Every thread maintains
- * a separate timer to ensure all counters are periodically aggregated. */
-void
-coverage_clear(void)
+ * a separate timer to ensure all counters are periodically aggregated.
+ *
+ * Uses 'ovs_mutex_trylock()' if 'trylock' is true. This is to prevent
+ * multiple performance-critical threads contending over the 'coverage_mutex'.
+ *
+ * */
+static void
+coverage_clear__(bool trylock)
{
long long int now, *thread_time;
if (now >= *thread_time) {
size_t i;
- ovs_mutex_lock(&coverage_mutex);
+ if (trylock) {
+ /* Returns if cannot acquire lock. */
+ if (ovs_mutex_trylock(&coverage_mutex)) {
+ return;
+ }
+ } else {
+ ovs_mutex_lock(&coverage_mutex);
+ }
+
for (i = 0; i < n_coverage_counters; i++) {
struct coverage_counter *c = coverage_counters[i];
c->total += c->count();
}
}
+void
+coverage_clear(void)
+{
+ coverage_clear__(false);
+}
+
+void
+coverage_try_clear(void)
+{
+ coverage_clear__(true);
+}
+
/* Runs approximately every COVERAGE_RUN_INTERVAL amount of time to update the
* coverage counters' 'min' and 'hr' array. 'min' array is for cumulating
* per second counts into per minute count. 'hr' array is for cumulating per