commit 179ae84f7ef5225e03cd29cb9a75f6e90d2d7388
author Pavel Begunkov <asml.silence@gmail.com> Wed Oct 20 20:00:49 2021 +0100
committer Jens Axboe <axboe@kernel.dk> Thu Oct 21 08:27:17 2021 -0600
tree dc6205b3b64bdd5c8a49ea2b2978809d80c68462
parent 6450fe1f668f410fe2ab69c79a52a0929a4a8296

block: clean up blk_mq_submit_bio() merging

Combine blk_mq_sched_bio_merge() and blk_attempt_plug_merge() under a
common if, so we don't check it twice.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/daedc90d4029a5d1d73344771632b1faca3aaf81.1634755800.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block/blk-mq.c

diff --git a/block/blk-mq.c b/block/blk-mq.c
index 101466e..d04ee72 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -2481,7 +2481,6 @@ void blk_mq_submit_bio(struct bio *bio)
 {
 	struct request_queue *q = bdev_get_queue(bio->bi_bdev);
 	const int is_sync = op_is_sync(bio->bi_opf);
-	const int is_flush_fua = op_is_flush(bio->bi_opf);
 	struct request *rq;
 	struct blk_plug *plug;
 	bool same_queue_rq = false;
@@ -2495,12 +2494,12 @@ void blk_mq_submit_bio(struct bio *bio)
 	if (!bio_integrity_prep(bio))
 		goto queue_exit;
 
-	if (!is_flush_fua && !blk_queue_nomerges(q) &&
-	    blk_attempt_plug_merge(q, bio, nr_segs, &same_queue_rq))
-		goto queue_exit;
-
-	if (blk_mq_sched_bio_merge(q, bio, nr_segs))
-		goto queue_exit;
+	if (!blk_queue_nomerges(q) && bio_mergeable(bio)) {
+		if (blk_attempt_plug_merge(q, bio, nr_segs, &same_queue_rq))
+			goto queue_exit;
+		if (blk_mq_sched_bio_merge(q, bio, nr_segs))
+			goto queue_exit;
+	}
 
 	rq_qos_throttle(q, bio);
 
@@ -2543,7 +2542,7 @@ void blk_mq_submit_bio(struct bio *bio)
 		return;
 	}
 
-	if (is_flush_fua && blk_insert_flush(rq))
+	if (op_is_flush(bio->bi_opf) && blk_insert_flush(rq))
 		return;
 
 	if (plug && (q->nr_hw_queues == 1 ||