drbd: fix "stalled" empty resync

With sync-after dependencies, given "lucky" timing of pause/unpause
events, and the end of an empty (0 bits set) resync was sometimes not
detected on the SyncTarget, leading to a "stalled" SyncSource state.

Fixed this by expecting not only "Inconsistent -> UpToDate" but also
"Consistent -> UpToDate" transitions for the peer disk state
to end a resync.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
This commit is contained in:
Lars Ellenberg 2011-09-26 15:24:56 +02:00 committed by Philipp Reisner
parent 1e86ac48af
commit 40424e4a24

View File

@ -3169,9 +3169,14 @@ static int receive_state(struct drbd_conf *mdev, enum drbd_packets cmd, unsigned
os = ns = mdev->state;
spin_unlock_irq(&mdev->req_lock);
/* peer says his disk is uptodate, while we think it is inconsistent,
* and this happens while we think we have a sync going on. */
if (os.pdsk == D_INCONSISTENT && real_peer_disk == D_UP_TO_DATE &&
/* If this is the "end of sync" confirmation, usually the peer disk
* transitions from D_INCONSISTENT to D_UP_TO_DATE. For empty (0 bits
* set) resync started in PausedSyncT, or if the timing of pause-/
* unpause-sync events has been "just right", the peer disk may
* transition from D_CONSISTENT to D_UP_TO_DATE as well.
*/
if ((os.pdsk == D_INCONSISTENT || os.pdsk == D_CONSISTENT) &&
real_peer_disk == D_UP_TO_DATE &&
os.conn > C_CONNECTED && os.disk == D_UP_TO_DATE) {
/* If we are (becoming) SyncSource, but peer is still in sync
* preparation, ignore its uptodate-ness to avoid flapping, it