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blk-mq: optimise *end_request non-stat path

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We already have a blk_mq_need_time_stamp() check in
__blk_mq_end_request() to get a timestamp, hide all the statistics
accounting under it. It cuts some cycles for requests that don't need
stats, and is free otherwise.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/e0f2ea812e93a8adcd07101212e7d7e70ca304e7.1634115360.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Pavel Begunkov 2021-10-13 09:57:13 +01:00 committed by Jens Axboe
parent 4f7ab09a1c
commit 8971a3b7f1
1 changed files with 8 additions and 10 deletions
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18
block/blk-mq.c
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@ -579,20 +579,18 @@ void blk_mq_free_plug_rqs(struct blk_plug *plug)
inline void __blk_mq_end_request(struct request *rq, blk_status_t error)
{
u64 now = 0;
if (blk_mq_need_time_stamp(rq)) {
u64 now = ktime_get_ns();
if (blk_mq_need_time_stamp(rq))
now = ktime_get_ns();
if (rq->rq_flags & RQF_STATS) {
blk_mq_poll_stats_start(rq->q);
blk_stat_add(rq, now);
}
if (rq->rq_flags & RQF_STATS) {
blk_mq_poll_stats_start(rq->q);
blk_stat_add(rq, now);
blk_mq_sched_completed_request(rq, now);
blk_account_io_done(rq, now);
}
blk_mq_sched_completed_request(rq, now);
blk_account_io_done(rq, now);
if (rq->end_io) {
rq_qos_done(rq->q, rq);
rq->end_io(rq, error);