MINOR: listener: add relax_listener() function
There is a need for a small difference between resuming and relaxing
a listener.
When resuming, we expect that the listener may completely resume, this includes
unpausing or rebinding if required.
Resuming a listener is a best-effort operation: no matter the current state,
try our best to bring the listener up to the LI_READY state.
There are some cases where we only want to "relax" listeners that were
previously restricted using limit_listener() or listener_full() functions.
Here we don't want to ressucitate listeners, we're simply interested in
cancelling out the previous restriction.
To this day, listener_resume() on a unbound listener is broken, that's why
the need for this wasn't felt yet.
But we're trying to restore historical listener_resume() behavior, so we better
prepare for this by introducing an explicit relax_listener() function that
only does what is expected in such cases.
This commit depends on:
- "MINOR: listener/api: add lli hint to listener functions"
(cherry picked from commit bcad7e6319a00ea0278fcad8125ac7116d6c55a5)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
(cherry picked from commit d170427902ebfd1f5c06366ea84a1126df1b01c0)
Signed-off-by: Amaury Denoyelle <adenoyelle@haproxy.com>
(cherry picked from commit 9bfa34f748e5c5bc16902d2058849275fec005fe)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
(cherry picked from commit bb8673459c039031e025b22a49a8c29f41533fb5)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
diff --git a/src/listener.c b/src/listener.c
index bcc831a..84064d6 100644
--- a/src/listener.c
+++ b/src/listener.c
@@ -539,6 +539,33 @@
return ret;
}
+/* Same as resume_listener(), but will only work to resume from
+ * LI_FULL or LI_LIMITED states because we try to relax listeners that
+ * were temporarily restricted and not to resume inactive listeners that
+ * may have been paused or completely stopped in the meantime.
+ * Returns positive value for success and 0 for failure.
+ * It will need to operate under the proxy's lock and the listener's lock.
+ * The caller is responsible for indicating in lpx, lli whether the respective
+ * locks are already held (non-zero) or not (zero) so that the function pick
+ * the missing ones, in this order.
+ */
+int relax_listener(struct listener *l, int lpx, int lli)
+{
+ int ret = 1;
+
+ if (!lli)
+ HA_RWLOCK_WRLOCK(LISTENER_LOCK, &l->lock);
+
+ if (l->state != LI_FULL && l->state != LI_LIMITED)
+ goto end; /* listener may be suspended or even stopped */
+ ret = resume_listener(l, lpx, 1);
+
+ end:
+ if (!lli)
+ HA_RWLOCK_WRUNLOCK(LISTENER_LOCK, &l->lock);
+ return ret;
+}
+
/* Marks a ready listener as full so that the stream code tries to re-enable
* it upon next close() using resume_listener().
*/