+ long long int now, *thread_time;
+
+ now = time_msec();
+ thread_time = coverage_clear_time_get();
+
+ /* Initialize the coverage_clear_time. */
+ if (*thread_time == LLONG_MIN) {
+ *thread_time = now + COVERAGE_CLEAR_INTERVAL;
+ }
+
+ if (now >= *thread_time) {
+ size_t i;
+
+ ovs_mutex_lock(&coverage_mutex);
+ for (i = 0; i < n_coverage_counters; i++) {
+ struct coverage_counter *c = coverage_counters[i];
+ c->total += c->count();
+ }
+ ovs_mutex_unlock(&coverage_mutex);
+ *thread_time = now + COVERAGE_CLEAR_INTERVAL;
+ }
+}
+
+/* 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
+ * minute counts into per hour count. Every thread may call this function. */
+void
+coverage_run(void)
+{
+ /* Defines the moving average array index variables. */
+ static unsigned int min_idx, hr_idx;
+ struct coverage_counter **c = coverage_counters;
+ long long int now;
+
+ ovs_mutex_lock(&coverage_mutex);
+ now = time_msec();
+ /* Initialize the coverage_run_time. */
+ if (coverage_run_time == LLONG_MIN) {
+ coverage_run_time = now + COVERAGE_RUN_INTERVAL;
+ }
+
+ if (now >= coverage_run_time) {
+ size_t i, j;
+ /* Computes the number of COVERAGE_RUN_INTERVAL slots, since
+ * it is possible that the actual run interval is multiple of
+ * COVERAGE_RUN_INTERVAL. */
+ int slots = (now - coverage_run_time) / COVERAGE_RUN_INTERVAL + 1;
+
+ for (i = 0; i < n_coverage_counters; i++) {
+ unsigned int count, portion;
+ unsigned int m_idx = min_idx;
+ unsigned int h_idx = hr_idx;
+ unsigned int idx = idx_count;
+
+ /* Computes the differences between the current total and the one
+ * recorded in last invocation of coverage_run(). */
+ count = c[i]->total - c[i]->last_total;
+ c[i]->last_total = c[i]->total;
+ /* The count over the time interval is evenly distributed
+ * among slots by calculating the portion. */
+ portion = count / slots;
+
+ for (j = 0; j < slots; j++) {
+ /* Updates the index variables. */
+ /* The m_idx is increased from 0 to MIN_AVG_LEN - 1. Every
+ * time the m_idx finishes a cycle (a cycle is one minute),
+ * the h_idx is incremented by 1. */
+ m_idx = idx % MIN_AVG_LEN;
+ h_idx = idx / MIN_AVG_LEN;
+
+ c[i]->min[m_idx] = portion + (j == (slots - 1)
+ ? count % slots : 0);
+ c[i]->hr[h_idx] = m_idx == 0
+ ? c[i]->min[m_idx]
+ : (c[i]->hr[h_idx] + c[i]->min[m_idx]);
+ /* This is to guarantee that h_idx ranges from 0 to 59. */
+ idx = (idx + 1) % (MIN_AVG_LEN * HR_AVG_LEN);
+ }
+ }
+
+ /* Updates the global index variables. */
+ idx_count = (idx_count + slots) % (MIN_AVG_LEN * HR_AVG_LEN);
+ min_idx = idx_count % MIN_AVG_LEN;
+ hr_idx = idx_count / MIN_AVG_LEN;
+ /* Updates the run time. */
+ coverage_run_time = now + COVERAGE_RUN_INTERVAL;
+ }
+ ovs_mutex_unlock(&coverage_mutex);
+}
+
+static unsigned int
+coverage_array_sum(const unsigned int *arr, const unsigned int len)
+{
+ unsigned int sum = 0;