Hi, On Wed, Aug 30, 2017 at 08:15:02AM +0200, oleksandr@xxxxxxxxxxxxxx wrote: > Hello. > > Addressing your questions below. > > > Can't reproduce even with putting dmcypt on raid10 after applying my > > patch. > > Just a side note, that dm-crypt is not necessary here — I am able to trigger > hang with RAID10 and LVM only. > > > BTW, could you share us which blk-mq scheduler you are using on sata? > > Okay, now it makes sense. Previously, without your patch I was able to > reproduce the issue with "mq-deadline", "bfq" and "none". Now, I cannot > trigger it with "none" set, but "mq-deadline" still hangs for me. Does this > mean each scheduler should be modified separately? No, it shouldn't. > > > Could you apply the following debug patch and provide the dmesg log > > after running the commands below? > > Is it still relevant since I confirm issue to be fixed with "none"? Please try the following patch and previous patch together and see if they make a difference: >From bc5626b4b65c7ff26567e75f42584c2c43ffe7c1 Mon Sep 17 00:00:00 2001 From: Ming Lei <ming.lei@xxxxxxxxxx> Date: Wed, 30 Aug 2017 15:53:01 +0800 Subject: [PATCH] blk-mq: add requests in the tail of hctx->dispatch So that we can allow to insert request at the head of hctx->dispatch. Signed-off-by: Ming Lei <ming.lei@xxxxxxxxxx> --- block/blk-mq-sched.c | 2 +- block/blk-mq.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/block/blk-mq-sched.c b/block/blk-mq-sched.c index eeeea026fb47..b40dd063d61f 100644 --- a/block/blk-mq-sched.c +++ b/block/blk-mq-sched.c @@ -272,7 +272,7 @@ static bool blk_mq_sched_bypass_insert(struct blk_mq_hw_ctx *hctx, * the dispatch list. */ spin_lock(&hctx->lock); - list_add(&rq->queuelist, &hctx->dispatch); + list_add_tail(&rq->queuelist, &hctx->dispatch); spin_unlock(&hctx->lock); return true; } diff --git a/block/blk-mq.c b/block/blk-mq.c index 4603b115e234..fed3d0c16266 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -1067,7 +1067,7 @@ bool blk_mq_dispatch_rq_list(struct request_queue *q, struct list_head *list) blk_mq_put_driver_tag(rq); spin_lock(&hctx->lock); - list_splice_init(list, &hctx->dispatch); + list_splice_tail_init(list, &hctx->dispatch); spin_unlock(&hctx->lock); /* -- 2.9.5 -- Ming
