For now, we just trace plug for single queue device or drivers provide .commit_rqs, and have not trace plug for multiple queues device. But, unplug events will be recorded when call blk_mq_flush_plug_list(). Then, trace events will be asymmetrical, just have unplug and without plug.
This patch add trace plug and unplug for multiple queues device in blk_mq_make_request(). After that, we can accurately trace plug and unplug for multiple queues. Signed-off-by: Yufen Yu <[email protected]> --- block/blk-mq.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/block/blk-mq.c b/block/blk-mq.c index 5486c7d8b408..4aa673a6d285 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -1987,11 +1987,13 @@ static blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio) plug->rq_count--; } blk_add_rq_to_plug(plug, rq); + trace_block_plug(q); blk_mq_put_ctx(data.ctx); if (same_queue_rq) { data.hctx = same_queue_rq->mq_hctx; + trace_block_unplug(q, 1, true); blk_mq_try_issue_directly(data.hctx, same_queue_rq, &cookie, false, true); } -- 2.16.2.dirty
