Re: [PATCH v7 2/3] nvme-fc: avoid race between time out and tear down

Himanshu Madhani
2021-09-14T13:55:00Z

> On Sep 14, 2021, at 4:20 AM, Daniel Wagner <dwagner@suse.de> wrote:
>
> From: James Smart <jsmart2021@gmail.com>
>
> To avoid race between time out and tear down, in tear down process,
> first we quiesce the queue, and then delete the timer and cancel
> the time out work for the queue.
>
> This patch merges the admin and io sync ops into the queue teardown logic
> as shown in the RDMA patch 3017013dcc "nvme-rdma: avoid race between time
> out and tear down". There is no teardown_lock in nvme-fc.
>
> Signed-off-by: James Smart <jsmart2021@gmail.com>
> CC: Chao Leng <lengchao@huawei.com>
> Tested-by: Daniel Wagner <dwagner@suse.de>
> Reviewed-by: Daniel Wagner <dwagner@suse.de>
> Reviewed-by: Hannes Reinecke <hare@suse.de>
> ---
> drivers/nvme/host/fc.c | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/drivers/nvme/host/fc.c b/drivers/nvme/host/fc.c
> index b5d9a5507de5..6ebe68396712 100644
> --- a/drivers/nvme/host/fc.c
> +++ b/drivers/nvme/host/fc.c
> @@ -2487,6 +2487,7 @@ __nvme_fc_abort_outstanding_ios(struct nvme_fc_ctrl *ctrl, bool start_queues)
> */
> if (ctrl->ctrl.queue_count > 1) {
> nvme_stop_queues(&ctrl->ctrl);
> + nvme_sync_io_queues(&ctrl->ctrl);
> blk_mq_tagset_busy_iter(&ctrl->tag_set,
> nvme_fc_terminate_exchange, &ctrl->ctrl);
> blk_mq_tagset_wait_completed_request(&ctrl->tag_set);
> @@ -2510,6 +2511,7 @@ __nvme_fc_abort_outstanding_ios(struct nvme_fc_ctrl *ctrl, bool start_queues)
> * clean up the admin queue. Same thing as above.
> */
> blk_mq_quiesce_queue(ctrl->ctrl.admin_q);
> + blk_sync_queue(ctrl->ctrl.admin_q);
> blk_mq_tagset_busy_iter(&ctrl->admin_tag_set,
> nvme_fc_terminate_exchange, &ctrl->ctrl);
> blk_mq_tagset_wait_completed_request(&ctrl->admin_tag_set);
> --
> 2.29.2
>

Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>

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Himanshu Madhani Oracle Linux Engineering