Commit 3f98c753 authored by Ming Lei's avatar Ming Lei Committed by Jens Axboe
Browse files

block: don't check bio in blk_throtl_dispatch_work_fn 



The bio has been checked already before throttling, so no need to check
it again before dispatching it from throttle queue.

Add a helper of submit_bio_noacct_nocheck() for this purpose.

Signed-off-by: default avatarMing Lei <ming.lei@redhat.com>
Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20220216044514.2903784-5-ming.lei@redhat.com


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 29ff2362

block/blk-core.c

+17 −13
Original line number Diff line number Diff line
@@ -874,20 +874,8 @@ static void __submit_bio_noacct_mq(struct bio *bio) 
	current->bio_list = NULL;

}



/**

 * submit_bio_noacct - re-submit a bio to the block device layer for I/O

 * @bio:  The bio describing the location in memory and on the device.

 *

 * This is a version of submit_bio() that shall only be used for I/O that is

 * resubmitted to lower level drivers by stacking block drivers.  All file

 * systems and other upper level users of the block layer should use

 * submit_bio() instead.

 */

void submit_bio_noacct(struct bio *bio)

void submit_bio_noacct_nocheck(struct bio *bio)

{

	if (unlikely(!submit_bio_checks(bio)))

		return;



	/*

	 * We only want one ->submit_bio to be active at a time, else stack

	 * usage with stacked devices could be a problem.  Use current->bio_list
@@ -901,6 +889,22 @@ void submit_bio_noacct(struct bio *bio) 
	else

		__submit_bio_noacct(bio);

}



/**

 * submit_bio_noacct - re-submit a bio to the block device layer for I/O

 * @bio:  The bio describing the location in memory and on the device.

 *

 * This is a version of submit_bio() that shall only be used for I/O that is

 * resubmitted to lower level drivers by stacking block drivers.  All file

 * systems and other upper level users of the block layer should use

 * submit_bio() instead.

 */

void submit_bio_noacct(struct bio *bio)

{

	if (unlikely(!submit_bio_checks(bio)))

		return;

	submit_bio_noacct_nocheck(bio);

}

EXPORT_SYMBOL(submit_bio_noacct);



/**

block/blk-throttle.c

+1 −1
Original line number Diff line number Diff line
@@ -1218,7 +1218,7 @@ static void blk_throtl_dispatch_work_fn(struct work_struct *work) 
	if (!bio_list_empty(&bio_list_on_stack)) {

		blk_start_plug(&plug);

		while ((bio = bio_list_pop(&bio_list_on_stack)))

			submit_bio_noacct(bio);

			submit_bio_noacct_nocheck(bio);

		blk_finish_plug(&plug);

	}

}

block/blk.h

+1 −0
Original line number Diff line number Diff line
@@ -46,6 +46,7 @@ void blk_freeze_queue(struct request_queue *q); 
void __blk_mq_unfreeze_queue(struct request_queue *q, bool force_atomic);

void blk_queue_start_drain(struct request_queue *q);

int __bio_queue_enter(struct request_queue *q, struct bio *bio);

void submit_bio_noacct_nocheck(struct bio *bio);



static inline bool blk_try_enter_queue(struct request_queue *q, bool pm)

{