Messages in this thread Patch in this message | | | From | Daniel Wagner <> | Subject | [PATCH v4 6/8] nvme-fc: fix controller reset hang during traffic | Date | Mon, 2 Aug 2021 11:14:17 +0200 |
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From: James Smart <jsmart2021@gmail.com>
commit fe35ec58f0d3 ("block: update hctx map when use multiple maps") exposed an issue where we may hang trying to wait for queue freeze during I/O. We call blk_mq_update_nr_hw_queues which may attempt to freeze the queue. However we never started queue freeze when starting the reset, which means that we have inflight pending requests that entered the queue that we will not complete once the queue is quiesced.
So start a freeze before we quiesce the queue, and unfreeze the queue after we successfully connected the I/O queues (the unfreeze is already present in the code). blk_mq_update_nr_hw_queues will be called only after we are sure that the queue was already frozen.
This follows to how the pci driver handles resets.
This patch added logic introduced in commit 9f98772ba307 "nvme-rdma: fix controller reset hang during traffic".
Signed-off-by: James Smart <jsmart2021@gmail.com> CC: Sagi Grimberg <sagi@grimberg.me> [dwagner: call nvme_unfreeze() unconditionally in nvme_fc_recreate_io_queues() to match the nvme_start_freeze()] Tested-by: Daniel Wagner <dwagner@suse.de> Reviewed-by: Daniel Wagner <dwagner@suse.de> --- drivers/nvme/host/fc.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/nvme/host/fc.c b/drivers/nvme/host/fc.c index 133b87db4f1d..b292af0fd655 100644 --- a/drivers/nvme/host/fc.c +++ b/drivers/nvme/host/fc.c @@ -2486,6 +2486,7 @@ __nvme_fc_abort_outstanding_ios(struct nvme_fc_ctrl *ctrl, bool start_queues) * (but with error status). */ if (ctrl->ctrl.queue_count > 1) { + nvme_start_freeze(&ctrl->ctrl); nvme_stop_queues(&ctrl->ctrl); nvme_sync_io_queues(&ctrl->ctrl); blk_mq_tagset_busy_iter(&ctrl->tag_set, @@ -2966,8 +2967,8 @@ nvme_fc_recreate_io_queues(struct nvme_fc_ctrl *ctrl) return -ENODEV; } blk_mq_update_nr_hw_queues(&ctrl->tag_set, nr_io_queues); - nvme_unfreeze(&ctrl->ctrl); } + nvme_unfreeze(&ctrl->ctrl); ret = nvme_fc_create_hw_io_queues(ctrl, ctrl->ctrl.sqsize + 1); if (ret) -- 2.29.2
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