Commit 459b5401 authored Jan 11, 2018 by Ming Lei Committed by Mike Snitzer Jan 17, 2018

dm mpath: return DM_MAPIO_DELAY_REQUEUE if QUEUE_IO or PG_INIT_REQUIRED



Avoid using DM_MAPIO_REQUEUE unless absolutely necessary because it
results in dm-rq.c:dm_mq_queue_rq() returning BLK_STS_RESOURCE to
blk-mq -- doing so should only ever be done if the underlying queue is
out of resources.  So switch to returning DM_MAPIO_DELAY_REQUEUE from
multipath_clone_and_map() if either MPATHF_QUEUE_IO or
MPATHF_PG_INIT_REQUIRED are set.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

parent 050af08f

drivers/md/dm-mpath.c

+2 −3

Original line number	Diff line number	Diff line
		@@ -517,9 +517,8 @@ static int multipath_clone_and_map(struct dm_target ti, struct request rq,
		return DM_MAPIO_KILL;
		} else if (test_bit(MPATHF_QUEUE_IO, &m->flags) \|\|
		test_bit(MPATHF_PG_INIT_REQUIRED, &m->flags)) {
		if (pg_init_all_paths(m))
		pg_init_all_paths(m);
		return DM_MAPIO_DELAY_REQUEUE;
		return DM_MAPIO_REQUEUE;
		}

		mpio->pgpath = pgpath;

Admin message