diff options
| author | Ming Lei <ming.lei@redhat.com> | 2019-09-27 15:24:31 +0800 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2019-09-27 11:40:21 -0600 |
| commit | 3154df262db52f1d27e01020e871f4345ec2f9a8 (patch) | |
| tree | c8cc0d818b1786463213c4a62d885ffaa47a1874 | |
| parent | a12de1d42d74ef3c80e9fb9a2da94daaef747869 (diff) | |
| download | linux-3154df262db52f1d27e01020e871f4345ec2f9a8.tar.bz2 | |
blk-mq: apply normal plugging for HDD
Some HDD drive may expose multiple hardware queues, such as MegraRaid.
Let's apply the normal plugging for such devices because sequential IO
may benefit a lot from plug merging.
Cc: Bart Van Assche <bvanassche@acm.org>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
| -rw-r--r-- | block/blk-mq.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/block/blk-mq.c b/block/blk-mq.c index 5d4bef3c378d..ec791156e9cc 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -1992,10 +1992,14 @@ static blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio) /* bypass scheduler for flush rq */ blk_insert_flush(rq); blk_mq_run_hw_queue(data.hctx, true); - } else if (plug && (q->nr_hw_queues == 1 || q->mq_ops->commit_rqs)) { + } else if (plug && (q->nr_hw_queues == 1 || q->mq_ops->commit_rqs || + !blk_queue_nonrot(q))) { /* * Use plugging if we have a ->commit_rqs() hook as well, as * we know the driver uses bd->last in a smart fashion. + * + * Use normal plugging if this disk is slow HDD, as sequential + * IO may benefit a lot from plug merging. */ unsigned int request_count = plug->rq_count; struct request *last = NULL; |