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blk-mq: add timer in blk_mq_start_request 

This way will become consistent with non-mq case, also
avoid to update rq->deadline twice for mq.

The comment said: "We do this early, to ensure we are on
the right CPU.", but no percpu stuff is used in blk_add_timer(),
so it isn't necessary. Even when inserting from plug list, there
is no such guarantee at all.

Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
hifive-unleashed-5.1
Ming Lei 2014-06-10 00:16:41 +08:00 committed by Jens Axboe
parent 3ee3237239
commit 2b8393b43e
1 changed files with 1 additions and 16 deletions
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17
block/blk-mq.c
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@ -411,16 +411,7 @@ static void blk_mq_start_request(struct request *rq, bool last)
if (unlikely(blk_bidi_rq(rq)))
rq->next_rq->resid_len = blk_rq_bytes(rq->next_rq);
/*
* Just mark start time and set the started bit. Due to memory
* ordering, we know we'll see the correct deadline as long as
* REQ_ATOMIC_STARTED is seen. Use the default queue timeout,
* unless one has been set in the request.
*/
if (!rq->timeout)
rq->deadline = jiffies + q->rq_timeout;
else
rq->deadline = jiffies + rq->timeout;
blk_add_timer(rq);
/*
* Mark us as started and clear complete. Complete might have been
@ -972,11 +963,6 @@ static void __blk_mq_insert_request(struct blk_mq_hw_ctx *hctx,
list_add_tail(&rq->queuelist, &ctx->rq_list);
blk_mq_hctx_mark_pending(hctx, ctx);
/*
* We do this early, to ensure we are on the right CPU.
*/
blk_add_timer(rq);
}
void blk_mq_insert_request(struct request *rq, bool at_head, bool run_queue,
@ -1219,7 +1205,6 @@ static void blk_mq_make_request(struct request_queue *q, struct bio *bio)
blk_mq_bio_to_request(rq, bio);
blk_mq_start_request(rq, true);
blk_add_timer(rq);
/*
* For OK queue, we are done. For error, kill it. Any other