On Tue, 2018-06-19 at 15:00 +0800, Jianchao Wang wrote: > blk_rq_timeout is needed to limit the max timeout value, otherwise, > a idle hctx cannot be deactivated timely in shared-tag case. > > Fixes: 12f5b931 (blk-mq: Remove generation seqeunce) > Signed-off-by: Jianchao Wang <jianchao.w.wang@xxxxxxxxxx> > --- > block/blk-mq.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/block/blk-mq.c b/block/blk-mq.c > index 70c65bb..ccebe7b 100644 > --- a/block/blk-mq.c > +++ b/block/blk-mq.c > @@ -868,7 +868,7 @@ static void blk_mq_timeout_work(struct work_struct *work) > blk_mq_queue_tag_busy_iter(q, blk_mq_check_expired, &next); > > if (next != 0) { > - mod_timer(&q->timeout, next); > + mod_timer(&q->timeout, blk_rq_timeout(round_jiffies_up(next))); > } else { > /* > * Request timeouts are handled as a forward rolling timer. If Hello Jianchao, What makes you think that it would be necessary to call blk_rq_timeout() from blk_mq_timeout_work()? Have you noticed that blk_add_timer() already calls that function? I think it is not necessary to call blk_rq_timeout() from blk_mq_timeout_work() because it is guaranteed in that function that the next timeout is less than BLK_MAX_TIMEOUT jiffies in the future. Bart.