Merge pull request #1625 from fengzeroz/v2.6

event: log get event fail

src/event/event_linux.c

@@ -213,6 +213,9 @@ neu_event_timer_t *neu_event_add_timer(neu_events_t *          events,
         .it_interval.tv_nsec = timer.millisecond * 1000 * 1000,
     };
     int index = get_free_event(events);
+    if (index < 0) {
+        zlog_notice(neuron, "no free event: %d", events->epoll_fd);
+    }
     assert(index >= 0);
 
     neu_event_timer_t *timer_ctx = &events->event_datas[index].ctx.timer;