From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Bart Van Assche To: Jens Axboe CC: , , "Bart Van Assche" , Mike Snitzer , Subject: [PATCH v4 6/6] dm rq: Avoid that request processing stalls sporadically Date: Fri, 7 Apr 2017 11:16:54 -0700 Message-ID: <20170407181654.27836-7-bart.vanassche@sandisk.com> In-Reply-To: <20170407181654.27836-1-bart.vanassche@sandisk.com> References: <20170407181654.27836-1-bart.vanassche@sandisk.com> MIME-Version: 1.0 Content-Type: text/plain Return-Path: Bart.VanAssche@sandisk.com List-ID: While running the srp-test software I noticed that request processing stalls sporadically at the beginning of a test, namely when mkfs is run against a dm-mpath device. Every time when that happened the following command was sufficient to resume request processing: echo run >/sys/kernel/debug/block/dm-0/state This patch avoids that such request processing stalls occur. The test I ran is as follows: while srp-test/run_tests -d -r 30 -t 02-mq; do :; done Signed-off-by: Bart Van Assche Cc: Mike Snitzer Cc: dm-devel@redhat.com --- drivers/md/dm-rq.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/md/dm-rq.c b/drivers/md/dm-rq.c index 6886bf160fb2..d19af1d21f4c 100644 --- a/drivers/md/dm-rq.c +++ b/drivers/md/dm-rq.c @@ -755,6 +755,7 @@ static int dm_mq_queue_rq(struct blk_mq_hw_ctx *hctx, /* Undo dm_start_request() before requeuing */ rq_end_stats(md, rq); rq_completed(md, rq_data_dir(rq), false); + blk_mq_delay_run_hw_queue(hctx, 100/*ms*/); return BLK_MQ_RQ_QUEUE_BUSY; } -- 2.12.0