| Message ID | e0f2ea812e93a8adcd07101212e7d7e70ca304e7.1634115360.git.asml.silence@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | on top of for-5.16/block | expand |
On Wed, Oct 13, 2021 at 09:57:13AM +0100, Pavel Begunkov wrote: > 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. The transformation is a little non-obvious due to the checks hidden inblk_mq_need_time_stamp, but after following all the spaghetti it does looks like a correct transformation: Reviewed-by: Christoph Hellwig <hch@lst.de>
diff --git a/block/blk-mq.c b/block/blk-mq.c index 38e6651d8b94..3dd3b22bc280 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -572,20 +572,18 @@ 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);
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> --- block/blk-mq.c | 18 ++++++++---------- 1 file changed, 8 insertions(+), 10 deletions(-)