Commit 90b8faa0 authored Oct 15, 2021 by Jens Axboe

block: only mark bio as tracked if it really is tracked



We set BIO_TRACKED unconditionally when rq_qos_throttle() is called, even
though we may not even have an rq_qos handler. Only mark it as TRACKED if
it really is potentially tracked.

This saves considerable time for the case where the bio isn't tracked:

     2.64%     -1.65%  [kernel.vmlinux]  [k] bio_endio

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

parent b6087629

block/blk-rq-qos.h

+3 −2

Original line number	Diff line number	Diff line
		@@ -189,10 +189,11 @@ static inline void rq_qos_throttle(struct request_queue q, struct bio bio)
		* BIO_TRACKED lets controllers know that a bio went through the
		* normal rq_qos path.
		*/
		if (q->rq_qos) {
		bio_set_flag(bio, BIO_TRACKED);
		if (q->rq_qos)
		__rq_qos_throttle(q->rq_qos, bio);
		}
		}

		static inline void rq_qos_track(struct request_queue q, struct request rq,
		struct bio *bio)