When direct issue is done on request picked up from plug list, the hctx need to be updated with the actual hw queue, otherwise wrong hctx is used and may hurt performance, especially when wrong SRCU readlock is acquired/released
Reported-by: Bart Van Assche <[email protected]> Signed-off-by: Ming Lei <[email protected]> --- block/blk-mq.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/block/blk-mq.c b/block/blk-mq.c index 58688205c8f4..c13888922e18 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -1558,9 +1558,12 @@ static blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio) blk_mq_put_ctx(data.ctx); - if (same_queue_rq) + if (same_queue_rq) { + data.hctx = blk_mq_map_queue(q, + same_queue_rq->mq_ctx->cpu); blk_mq_try_issue_directly(data.hctx, same_queue_rq, &cookie); + } } else if (q->nr_hw_queues > 1 && is_sync) { blk_mq_put_ctx(data.ctx); blk_mq_bio_to_request(rq, bio); -- 2.9.4
