drbd: Reduce the time an empty resync takes usually

This mitigates changes introduced with commit:
http://git.drbd.org/?p=drbd-8.3.git;a=commit;h=4b6803a3276652da3737

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>

diff --git a/drivers/block/drbd/drbd_int.h b/drivers/block/drbd/drbd_int.h
index 844206c..2d5cebb 100644 (file)
--- a/drivers/block/drbd/drbd_int.h
+++ b/drivers/block/drbd/drbd_int.h
@@ -800,6 +800,7 @@ enum {
        RESIZE_PENDING,         /* Size change detected locally, waiting for the response from
                                 * the peer, if it changed there as well. */
        CONN_DRY_RUN,           /* Expect disconnect after resync handshake. */
+       GOT_PING_ACK,           /* set when we receive a ping_ack packet, misc wait gets woken */
 };
 
 struct drbd_bitmap; /* opaque for drbd_conf */

diff --git a/drivers/block/drbd/drbd_receiver.c b/drivers/block/drbd/drbd_receiver.c
index d803e6c..ed9f1de 100644 (file)
--- a/drivers/block/drbd/drbd_receiver.c
+++ b/drivers/block/drbd/drbd_receiver.c
@@ -4074,6 +4074,8 @@ static int got_PingAck(struct drbd_conf *mdev, struct p_header *h)
 {
        /* restore idle timeout */
        mdev->meta.socket->sk->sk_rcvtimeo = mdev->net_conf->ping_int*HZ;
+       if (!test_and_set_bit(GOT_PING_ACK, &mdev->flags))
+               wake_up(&mdev->misc_wait);
 
        return TRUE;
 }

diff --git a/drivers/block/drbd/drbd_worker.c b/drivers/block/drbd/drbd_worker.c
index d97a811..4672f2f 100644 (file)
--- a/drivers/block/drbd/drbd_worker.c
+++ b/drivers/block/drbd/drbd_worker.c
@@ -1289,6 +1289,14 @@ int drbd_alter_sa(struct drbd_conf *mdev, int na)
        return retcode;
 }
 
+static void ping_peer(struct drbd_conf *mdev)
+{
+       clear_bit(GOT_PING_ACK, &mdev->flags);
+       request_ping(mdev);
+       wait_event(mdev->misc_wait,
+                  test_bit(GOT_PING_ACK, &mdev->flags) || mdev->state.conn < C_CONNECTED);
+}
+
 /**
  * drbd_start_resync() - Start the resync process
  * @mdev:      DRBD device.
@@ -1383,9 +1391,7 @@ void drbd_start_resync(struct drbd_conf *mdev, enum drbd_conns side)
 
                if (mdev->rs_total == 0) {
                        /* Peer still reachable? Beware of failing before-resync-target handlers! */
-                       request_ping(mdev);
-                       __set_current_state(TASK_INTERRUPTIBLE);
-                       schedule_timeout(mdev->net_conf->ping_timeo*HZ/9); /* 9 instead 10 */
+                       ping_peer(mdev);
                        drbd_resync_finished(mdev);
                        return;
                }