[PATCH 2/2] blk-mq: immediately dispatch big size request
From: Shaohua Li <hidden>
Date: 2016-10-28 22:52:42
Also in:
lkml
Subsystem:
block layer, the rest · Maintainers:
Jens Axboe, Linus Torvalds
This is corresponding part for blk-mq. Disk with multiple hardware queues doesn't need this as we only hold 1 request at most. Signed-off-by: Shaohua Li <redacted> --- block/blk-mq.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/block/blk-mq.c b/block/blk-mq.c
index f3d27a6..9612306 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c@@ -1401,13 +1401,18 @@ static blk_qc_t blk_sq_make_request(struct request_queue *q, struct bio *bio) */ plug = current->plug; if (plug) { + struct request *first = NULL; + blk_mq_bio_to_request(rq, bio); if (!request_count) trace_block_plug(q); + else + first = list_entry_rq(plug->mq_list.next); blk_mq_put_ctx(data.ctx); - if (request_count >= BLK_MAX_REQUEST_COUNT) { + if (request_count >= BLK_MAX_REQUEST_COUNT || (first && + blk_rq_bytes(first) >= BLK_PLUG_FLUSH_SIZE)) { blk_flush_plug_list(plug, false); trace_block_plug(q); }
--
2.9.3