From da661267398869a553b7f67d739d360aaa1361b6 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Thu, 14 Jun 2018 13:58:45 +0200 Subject: blk-mq: don't time out requests again that are in the timeout handler We can currently call the timeout handler again on a request that has already been handed over to the timeout handler. Prevent that with a new flag. Fixes: 12f5b931 ("blk-mq: Remove generation seqeunce") Reported-by: Andrew Randrianasulu Tested-by: Andrew Randrianasulu Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe --- block/blk-mq.c | 5 +++++ include/linux/blkdev.h | 2 ++ 2 files changed, 7 insertions(+) diff --git a/block/blk-mq.c b/block/blk-mq.c index 2be78cc30ec5..8e57b84e50e9 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -671,6 +671,7 @@ static void __blk_mq_requeue_request(struct request *rq) if (blk_mq_request_started(rq)) { WRITE_ONCE(rq->state, MQ_RQ_IDLE); + rq->rq_flags &= ~RQF_TIMED_OUT; if (q->dma_drain_size && blk_rq_bytes(rq)) rq->nr_phys_segments--; } @@ -770,6 +771,7 @@ EXPORT_SYMBOL(blk_mq_tag_to_rq); static void blk_mq_rq_timed_out(struct request *req, bool reserved) { + req->rq_flags |= RQF_TIMED_OUT; if (req->q->mq_ops->timeout) { enum blk_eh_timer_return ret; @@ -779,6 +781,7 @@ static void blk_mq_rq_timed_out(struct request *req, bool reserved) WARN_ON_ONCE(ret != BLK_EH_RESET_TIMER); } + req->rq_flags &= ~RQF_TIMED_OUT; blk_add_timer(req); } @@ -788,6 +791,8 @@ static bool blk_mq_req_expired(struct request *rq, unsigned long *next) if (blk_mq_rq_state(rq) != MQ_RQ_IN_FLIGHT) return false; + if (rq->rq_flags & RQF_TIMED_OUT) + return false; deadline = blk_rq_deadline(rq); if (time_after_eq(jiffies, deadline)) diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index bca3a92eb55f..fa6f11751430 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -127,6 +127,8 @@ typedef __u32 __bitwise req_flags_t; #define RQF_ZONE_WRITE_LOCKED ((__force req_flags_t)(1 << 19)) /* already slept for hybrid poll */ #define RQF_MQ_POLL_SLEPT ((__force req_flags_t)(1 << 20)) +/* ->timeout has been called, don't expire again */ +#define RQF_TIMED_OUT ((__force req_flags_t)(1 << 21)) /* flags that prevent us from merging requests: */ #define RQF_NOMERGE_FLAGS \ -- cgit