drbd: skip spurious timeout (ping-timeo) when failing promote

If you try to promote a Secondary while connected to a Primary
and allow-two-primaries is NOT set, we will wait for "ping-timeout"
to give this node a chance to detect a dead primary,
in case the cluster manager noticed faster than we did.

But if we then are *still* connected to a Primary,
we fail (after an additional timeout of ping-timout).

This change skips the spurious second timeout.

Most people won't notice really,
since "ping-timeout" by default is half a second.

But in some installations, ping-timeout may be 10 or 20 seconds or more,
and spuriously delaying the error return becomes annoying.

Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/drivers/block/drbd/drbd_nl.c b/drivers/block/drbd/drbd_nl.c
index 8291588..bfe1b00 100644 (file)
--- a/drivers/block/drbd/drbd_nl.c
+++ b/drivers/block/drbd/drbd_nl.c
@@ -697,14 +697,15 @@ drbd_set_role(struct drbd_device *const device, enum drbd_role new_role, int for
                if (rv == SS_TWO_PRIMARIES) {
                        /* Maybe the peer is detected as dead very soon...
                           retry at most once more in this case. */
-                       int timeo;
-                       rcu_read_lock();
-                       nc = rcu_dereference(connection->net_conf);
-                       timeo = nc ? (nc->ping_timeo + 1) * HZ / 10 : 1;
-                       rcu_read_unlock();
-                       schedule_timeout_interruptible(timeo);
-                       if (try < max_tries)
+                       if (try < max_tries) {
+                               int timeo;
                                try = max_tries - 1;
+                               rcu_read_lock();
+                               nc = rcu_dereference(connection->net_conf);
+                               timeo = nc ? (nc->ping_timeo + 1) * HZ / 10 : 1;
+                               rcu_read_unlock();
+                               schedule_timeout_interruptible(timeo);
+                       }
                        continue;
                }
                if (rv < SS_SUCCESS) {