Make sure that common timeouts are inserted in-order.

This code should be a no-op, except under strange thread contention
situations.

svn:r1519

diff --git a/event.c b/event.c
index 327546e222046074f9780df150346ace2b4375be..8f25f251393a38711a025410546b0b8383bd8709 100644 (file)
--- a/event.c
+++ b/event.c
@@ -1882,6 +1882,29 @@ event_queue_remove(struct event_base *base, struct event *ev, int queue)
        }
 }
 
+static void
+insert_common_timeout_inorder(struct common_timeout_list *ctl,
+    struct event *ev)
+{
+       struct event *e;
+       TAILQ_FOREACH_REVERSE(e, &ctl->events,
+           ev_timeout_pos.ev_next_with_common_timeout, event_list) {
+               /* This timercmp is a little sneaky, since both ev and e have
+                * magic values in tv_usec.  Fortunately, they ought to have
+                * the _same_ magic values in tv_usec.  Let's assert for that.
+                */
+               EVUTIL_ASSERT((e->ev_timeout.tv_usec & ~MICROSECONDS_MASK)
+                   == (ev->ev_timeout.tv_usec & ~MICROSECONDS_MASK));
+               if (evutil_timercmp(&ev->ev_timeout, &e->ev_timeout, >=)) {
+                       TAILQ_INSERT_AFTER(&ctl->events, e, ev,
+                           ev_timeout_pos.ev_next_with_common_timeout);
+                       return;
+               }
+       }
+       TAILQ_INSERT_HEAD(&ctl->events, ev,
+           ev_timeout_pos.ev_next_with_common_timeout);
+}
+
 static void
 event_queue_insert(struct event_base *base, struct event *ev, int queue)
 {
@@ -1911,8 +1934,7 @@ event_queue_insert(struct event_base *base, struct event *ev, int queue)
                if (is_common_timeout(&ev->ev_timeout, base)) {
                        struct common_timeout_list *ctl =
                            get_common_timeout_list(base, &ev->ev_timeout);
-                       TAILQ_INSERT_TAIL(&ctl->events, ev,
-                           ev_timeout_pos.ev_next_with_common_timeout);
+                       insert_common_timeout_inorder(ctl, ev);
                } else
                        min_heap_push(&base->timeheap, ev);
                break;