On Wed, May 23, 2018 at 02:19:30PM +0200, Christoph Hellwig wrote:
> NVMe always completes the request before returning from ->timeout, either
> by polling for it, or by disabling the controller. Return BLK_EH_DONE so
> that the block layer doesn't even try to complete it again.
>
> Signed-off-by: Christoph Hellwig <hch@xxxxxx>
> ---
> drivers/nvme/host/pci.c | 14 +++++---------
> drivers/nvme/host/rdma.c | 2 +-
> drivers/nvme/target/loop.c | 2 +-
> 3 files changed, 7 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
> index 917e1714f7d9..31525324b79f 100644
> --- a/drivers/nvme/host/pci.c
> +++ b/drivers/nvme/host/pci.c
> @@ -1205,7 +1205,7 @@ static enum blk_eh_timer_return nvme_timeout(struct request *req, bool reserved)
> nvme_warn_reset(dev, csts);
> nvme_dev_disable(dev, false);
> nvme_reset_ctrl(&dev->ctrl);
> - return BLK_EH_HANDLED;
> + return BLK_EH_DONE;
> }
>
> /*
> @@ -1215,14 +1215,14 @@ static enum blk_eh_timer_return nvme_timeout(struct request *req, bool reserved)
> dev_warn(dev->ctrl.device,
> "I/O %d QID %d timeout, completion polled\n",
> req->tag, nvmeq->qid);
> - return BLK_EH_HANDLED;
> + return BLK_EH_DONE;
> }
>
> /*
> * Shutdown immediately if controller times out while starting. The
> * reset work will see the pci device disabled when it gets the forced
> * cancellation error. All outstanding requests are completed on
> - * shutdown, so we return BLK_EH_HANDLED.
> + * shutdown, so we return BLK_EH_DONE.
> */
> switch (dev->ctrl.state) {
> case NVME_CTRL_CONNECTING:
> @@ -1232,7 +1232,7 @@ static enum blk_eh_timer_return nvme_timeout(struct request *req, bool reserved)
> req->tag, nvmeq->qid);
> nvme_dev_disable(dev, false);
> nvme_req(req)->flags |= NVME_REQ_CANCELLED;
> - return BLK_EH_HANDLED;
> + return BLK_EH_DONE;
> default:
> break;
> }
> @@ -1249,12 +1249,8 @@ static enum blk_eh_timer_return nvme_timeout(struct request *req, bool reserved)
> nvme_dev_disable(dev, false);
> nvme_reset_ctrl(&dev->ctrl);
>
> - /*
> - * Mark the request as handled, since the inline shutdown
> - * forces all outstanding requests to complete.
> - */
> nvme_req(req)->flags |= NVME_REQ_CANCELLED;
> - return BLK_EH_HANDLED;
> + return BLK_EH_DONE;
> }
>
> if (atomic_dec_return(&dev->ctrl.abort_limit) < 0) {
> diff --git a/drivers/nvme/host/rdma.c b/drivers/nvme/host/rdma.c
> index 1eb4438a8763..ac7462cd7f0f 100644
> --- a/drivers/nvme/host/rdma.c
> +++ b/drivers/nvme/host/rdma.c
> @@ -1598,7 +1598,7 @@ nvme_rdma_timeout(struct request *rq, bool reserved)
> /* fail with DNR on cmd timeout */
> nvme_req(rq)->status = NVME_SC_ABORT_REQ | NVME_SC_DNR;
>
> - return BLK_EH_HANDLED;
> + return BLK_EH_DONE;
> }
>
> static blk_status_t nvme_rdma_queue_rq(struct blk_mq_hw_ctx *hctx,
> diff --git a/drivers/nvme/target/loop.c b/drivers/nvme/target/loop.c
> index 27a8561c0cb9..22e3627bf16b 100644
> --- a/drivers/nvme/target/loop.c
> +++ b/drivers/nvme/target/loop.c
> @@ -146,7 +146,7 @@ nvme_loop_timeout(struct request *rq, bool reserved)
> /* fail with DNR on admin cmd timeout */
> nvme_req(rq)->status = NVME_SC_ABORT_REQ | NVME_SC_DNR;
>
> - return BLK_EH_HANDLED;
> + return BLK_EH_DONE;
> }
>
> static blk_status_t nvme_loop_queue_rq(struct blk_mq_hw_ctx *hctx,
> --
> 2.17.0
>
This change should have been done after '[PATCH 13/14] blk-mq: Remove
generation seqeunce', otherwise the timed-out request won't be completed
by nvme_cancel_request() at all because we always marked this request as
'COMPLETE' before calling .timeout().
Thanks,
Ming
