block, bfq: remove the removal of 'next' rq in bfq_requests_merged (ac857e0d) · Commits · 戴 / test

Since bfq_finish_request() is always called on the request 'next', after bfq_requests_merged() is finished, and bfq_finish_request() removes 'next' from its bfq_queue if needed, it isn't necessary to do such a removal in advance in bfq_merged_requests(). This commit removes such a useless 'next' removal. Signed-off-by:

Filippo Muzzini <filippo.muzzini@outlook.it> Signed-off-by:

Paolo Valente <paolo.valente@linaro.org> Signed-off-by:

Jens Axboe <axboe@kernel.dk>

block/bfq-iosched.c

+0 −7

Original line number	Diff line number	Diff line
		@@ -1845,8 +1845,6 @@ static void bfq_request_merged(struct request_queue q, struct request req,
		* exploits this hook to address the following issue: if 'next' has a
		* fifo_time lower that rq, then the fifo_time of rq must be set to
		* the value of 'next', to not forget the greater age of 'next'.
		* Moreover 'next' may be in a bfq_queue, in this case it must be
		* removed.
		*
		* NOTE: in this function we assume that rq is in a bfq_queue, basing
		* on that rq is picked from the hash table q->elevator->hash, which,
		@@ -1881,11 +1879,6 @@ static void bfq_requests_merged(struct request_queue q, struct request rq,
		if (bfqq->next_rq == next)
		bfqq->next_rq = rq;

		if (!RB_EMPTY_NODE(&next->rb_node)) {
		bfq_remove_request(q, next);
		bfqg_stats_update_io_remove(bfqq_group(bfqq), next->cmd_flags);
		}

		bfqg_stats_update_io_merged(bfqq_group(bfqq), next->cmd_flags);
		}

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