Commit 9d1deb83 authored Feb 24, 2015 by Mike Snitzer

dm: don't schedule delayed run of the queue if nothing to do



In request-based DM's dm_request_fn(), if blk_peek_request() returns
NULL just return.  Avoids unnecessary blk_delay_queue().

Reported-by: Jens Axboe <axboe@fb.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

parent 9a0e609e

drivers/md/dm.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -1963,7 +1963,7 @@ static void dm_request_fn(struct request_queue *q)
		while (!blk_queue_stopped(q)) {
		rq = blk_peek_request(q);
		if (!rq)
		goto delay_and_out;
		goto out;

		/* always use block 0 to find the target for flushes for now */
		pos = 0;