Skip to content

Commit

Permalink
block, bfq: bring forward seek&think time update
Browse files Browse the repository at this point in the history
Until the base value for request service times gets finally computed
for a bfq_queue, the inject limit for that queue does depend on the
think-time state (short|long) of the queue. A timely update of the
think time then guarantees a quicker activation or deactivation of the
injection. Fortunately, the think time of a bfq_queue is updated in
the same code path as the inject limit; but after the inject limit.

This commits moves the update of the think time before the update of
the inject limit. For coherence, it moves the update of the seek time
too.

Reported-by: Srivatsa S. Bhat (VMware) <srivatsa@csail.mit.edu>
Tested-by: Srivatsa S. Bhat (VMware) <srivatsa@csail.mit.edu>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
  • Loading branch information
Paolo Valente authored and Jens Axboe committed Jun 25, 2019
1 parent 24792ad commit a3f9bce
Showing 1 changed file with 4 additions and 10 deletions.
14 changes: 4 additions & 10 deletions block/bfq-iosched.c
Original file line number Diff line number Diff line change
Expand Up @@ -4979,19 +4979,9 @@ static void bfq_update_has_short_ttime(struct bfq_data *bfqd,
static void bfq_rq_enqueued(struct bfq_data *bfqd, struct bfq_queue *bfqq,
struct request *rq)
{
struct bfq_io_cq *bic = RQ_BIC(rq);

if (rq->cmd_flags & REQ_META)
bfqq->meta_pending++;

bfq_update_io_thinktime(bfqd, bfqq);
bfq_update_has_short_ttime(bfqd, bfqq, bic);
bfq_update_io_seektime(bfqd, bfqq, rq);

bfq_log_bfqq(bfqd, bfqq,
"rq_enqueued: has_short_ttime=%d (seeky %d)",
bfq_bfqq_has_short_ttime(bfqq), BFQQ_SEEKY(bfqq));

bfqq->last_request_pos = blk_rq_pos(rq) + blk_rq_sectors(rq);

if (bfqq == bfqd->in_service_queue && bfq_bfqq_wait_request(bfqq)) {
Expand Down Expand Up @@ -5079,6 +5069,10 @@ static bool __bfq_insert_request(struct bfq_data *bfqd, struct request *rq)
bfqq = new_bfqq;
}

bfq_update_io_thinktime(bfqd, bfqq);
bfq_update_has_short_ttime(bfqd, bfqq, RQ_BIC(rq));
bfq_update_io_seektime(bfqd, bfqq, rq);

waiting = bfqq && bfq_bfqq_wait_request(bfqq);
bfq_add_request(rq);
idle_timer_disabled = waiting && !bfq_bfqq_wait_request(bfqq);
Expand Down

0 comments on commit a3f9bce

Please sign in to comment.