Commit be115b69 authored by Lars Ellenberg's avatar Lars Ellenberg Committed by Jens Axboe
Browse files

drbd: change bitmap write-out when leaving resync states 



When leaving resync states because of disconnect,
do the bitmap write-out synchronously in the drbd_disconnected() path.

When leaving resync states because we go back to AHEAD/BEHIND, or
because resync actually finished, or some disk was lost during resync,
trigger the write-out from after_state_ch().

The bitmap write-out for resync -> ahead/behind was missing completely before.

Note that this is all only an optimization to avoid double-resyncs of
already completed blocks in case this node crashes.

Signed-off-by: default avatarPhilipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: default avatarLars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: default avatarJens Axboe <axboe@fb.com>
parent c0065f98

drivers/block/drbd/drbd_receiver.c

+5 −3
Original line number Diff line number Diff line
@@ -4795,9 +4795,11 @@ static int drbd_disconnected(struct drbd_peer_device *peer_device) 


	drbd_md_sync(device);



	/* serialize with bitmap writeout triggered by the state change,

	 * if any. */

	wait_event(device->misc_wait, !test_bit(BITMAP_IO, &device->flags));

	if (get_ldev(device)) {

		drbd_bitmap_io(device, &drbd_bm_write_copy_pages,

				"write from disconnected", BM_LOCKED_CHANGE_ALLOWED);

		put_ldev(device);

	}



	/* tcp_close and release of sendpage pages can be deferred.  I don't

	 * want to use SO_LINGER, because apparently it can be deferred for

drivers/block/drbd/drbd_state.c

+7 −2
Original line number Diff line number Diff line
@@ -1934,12 +1934,17 @@ static void after_state_ch(struct drbd_device *device, union drbd_state os, 


	/* This triggers bitmap writeout of potentially still unwritten pages

	 * if the resync finished cleanly, or aborted because of peer disk

	 * failure, or because of connection loss.

	 * failure, or on transition from resync back to AHEAD/BEHIND.

	 *

	 * Connection loss is handled in drbd_disconnected() by the receiver.

	 *

	 * For resync aborted because of local disk failure, we cannot do

	 * any bitmap writeout anymore.

	 *

	 * No harm done if some bits change during this phase.

	 */

	if (os.conn > C_CONNECTED && ns.conn <= C_CONNECTED && get_ldev(device)) {

	if ((os.conn > C_CONNECTED && os.conn < C_AHEAD) &&

	    (ns.conn == C_CONNECTED || ns.conn >= C_AHEAD) && get_ldev(device)) {

		drbd_queue_bitmap_io(device, &drbd_bm_write_copy_pages, NULL,

			"write from resync_finished", BM_LOCKED_CHANGE_ALLOWED);

		put_ldev(device);

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