Author: huhai &lt;huhai@kylinos.cn&gt;<br>Date: &nbsp; Wed May 16 10:34:22 2018 +0800<br><br>&nbsp; &nbsp; blk-mq: for sync case, whether it is mq or sq make_request instances, we should send the request directly<br>&nbsp; &nbsp; <br>&nbsp; &nbsp; For sq make_request instances, we should issue sync request directly too, <br>&nbsp; &nbsp; otherwise it will break down the semantics of sync request, <br>&nbsp; &nbsp; the current code logic is to send synchronous requests asynchronously.<br>&nbsp; &nbsp; <br>&nbsp; &nbsp; Signed-off-by: huhai &lt;huhai@kylinos.cn&gt;<br><br>diff --git a/block/blk-mq.c b/block/blk-mq.c<br>index 5629f18..fcf2f16 100644<br>--- a/block/blk-mq.c<br>+++ b/block/blk-mq.c<br>@@ -1771,7 +1771,7 @@ static blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio)<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &nbsp; blk_mq_try_issue_directly(data.hctx, same_queue_rq,<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &nbsp; &amp;cookie);<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &nbsp; }<br>-&nbsp;&nbsp;&nbsp;&nbsp; &nbsp; } else if (q-&gt;nr_hw_queues &gt; 1 &amp;&amp; is_sync) {<br>+&nbsp;&nbsp;&nbsp;&nbsp; &nbsp; } else if (is_sync) {<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &nbsp; blk_mq_put_ctx(data.ctx);<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &nbsp; blk_mq_bio_to_request(rq, bio);<br><div>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &nbsp; blk_mq_try_issue_directly(data.hctx, rq, &amp;cookie);</div><div><br></div><div><br></div><!--<![endif]-->