Commit 6deacb3b authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Jens Axboe
Browse files

block: simplify blk_mq_plug 



Drop the unused q argument, and invert the check to move the exception
into a branch and the regular path as the normal return.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarChaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: default avatarDamien Le Moal <damien.lemoal@opensource.wdc.com>
Reviewed-by: default avatarJohannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20220706070350.1703384-5-hch@lst.de


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent edd1dbc8

block/blk-core.c

+1 −1
Original line number Diff line number Diff line
@@ -719,7 +719,7 @@ void submit_bio_noacct(struct bio *bio) 


	might_sleep();



	plug = blk_mq_plug(q, bio);

	plug = blk_mq_plug(bio);

	if (plug && plug->nowait)

		bio->bi_opf |= REQ_NOWAIT;

block/blk-merge.c

+1 −1
Original line number Diff line number Diff line
@@ -1051,7 +1051,7 @@ bool blk_attempt_plug_merge(struct request_queue *q, struct bio *bio, 
	struct blk_plug *plug;

	struct request *rq;



	plug = blk_mq_plug(q, bio);

	plug = blk_mq_plug(bio);

	if (!plug || rq_list_empty(plug->mq_list))

		return false;

block/blk-mq.c

+1 −1
Original line number Diff line number Diff line
@@ -2808,7 +2808,7 @@ static void bio_set_ioprio(struct bio *bio) 
void blk_mq_submit_bio(struct bio *bio)

{

	struct request_queue *q = bdev_get_queue(bio->bi_bdev);

	struct blk_plug *plug = blk_mq_plug(q, bio);

	struct blk_plug *plug = blk_mq_plug(bio);

	const int is_sync = op_is_sync(bio->bi_opf);

	struct request *rq;

	unsigned int nr_segs = 1;

block/blk-mq.h

+8 −10
Original line number Diff line number Diff line
@@ -294,7 +294,6 @@ static inline void blk_mq_clear_mq_map(struct blk_mq_queue_map *qmap) 


/*

 * blk_mq_plug() - Get caller context plug

 * @q: request queue

 * @bio : the bio being submitted by the caller context

 *

 * Plugging, by design, may delay the insertion of BIOs into the elevator in
@@ -305,23 +304,22 @@ static inline void blk_mq_clear_mq_map(struct blk_mq_queue_map *qmap) 
 * order. While this is not a problem with regular block devices, this ordering

 * change can cause write BIO failures with zoned block devices as these

 * require sequential write patterns to zones. Prevent this from happening by

 * ignoring the plug state of a BIO issuing context if the target request queue

 * is for a zoned block device and the BIO to plug is a write operation.

 * ignoring the plug state of a BIO issuing context if it is for a zoned block

 * device and the BIO to plug is a write operation.

 *

 * Return current->plug if the bio can be plugged and NULL otherwise

 */

static inline struct blk_plug *blk_mq_plug(struct request_queue *q,

					   struct bio *bio)

static inline struct blk_plug *blk_mq_plug( struct bio *bio)

{

	/* Zoned block device write operation case: do not plug the BIO */

	if (bdev_is_zoned(bio->bi_bdev) && op_is_write(bio_op(bio)))

		return NULL;



	/*

	 * For regular block devices or read operations, use the context plug

	 * which may be NULL if blk_start_plug() was not executed.

	 */

	if (!bdev_is_zoned(bio->bi_bdev) || !op_is_write(bio_op(bio)))

	return current->plug;



	/* Zoned block device write operation case: do not plug the BIO */

	return NULL;

}



/* Free all requests on the list */