BUG: backend: stop looking for queued connections once there's no more
Commit ae0b12ee0 ("MEDIUM: queue: use a trylock on the server's queue")
introduced a hard to trigger bug that's more visible with a single thread:
if a server dequeues a connection and finds another free slot with no
connection to place there, process_srv_queue() will never break out of
the loop. In multi-thread it almost does not happen because other threads
bring new connections.
No backport is needed as it's only in -dev.
diff --git a/src/queue.c b/src/queue.c
index b7610d4..b7ca163 100644
--- a/src/queue.c
+++ b/src/queue.c
@@ -330,6 +330,7 @@
struct server *ref = s->track ? s->track : s;
struct proxy *p = s->proxy;
int maxconn;
+ int stop = 0;
int done = 0;
int px_ok;
@@ -345,13 +346,13 @@
* for the same server will give up, knowing that at least one of
* them will check the conditions again before quitting.
*/
- while (s->served < (maxconn = srv_dynamic_maxconn(s))) {
+ while (!stop && s->served < (maxconn = srv_dynamic_maxconn(s))) {
if (HA_SPIN_TRYLOCK(SERVER_LOCK, &s->queue.lock) != 0)
break;
while (s->served < maxconn) {
- int ret = pendconn_process_next_strm(s, p, px_ok);
- if (!ret)
+ stop = !pendconn_process_next_strm(s, p, px_ok);
+ if (stop)
break;
_HA_ATOMIC_INC(&s->served);
done++;