[PATCH 2/4] nvme-fc: quiesce/unquiesce admin_q instead of start/stop its hw queues

[James Smart]

On 7/2/2017 10:45 AM, Sagi Grimberg wrote:
> unlike blk_mq_stop_hw_queues and blk_mq_start_stopped_hw_queues
> quiescing/unquiescing respects the submission path rcu grace.
> Also make sure to kick the requeue list when appropriate.
>
> Signed-off-by: Sagi Grimberg <sagi at grimberg.me>
> ---
>   drivers/nvme/host/fc.c | 8 +++++---
>   1 file changed, 5 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/nvme/host/fc.c b/drivers/nvme/host/fc.c
> index ffe0589969bd..c5621b833c66 100644
> --- a/drivers/nvme/host/fc.c
> +++ b/drivers/nvme/host/fc.c
> @@ -2319,8 +2319,10 @@ nvme_fc_create_association(struct nvme_fc_ctrl *ctrl)
>   	if (ret)
>   		goto out_delete_hw_queue;
>   
> -	if (ctrl->ctrl.state != NVME_CTRL_NEW)
> -		blk_mq_start_stopped_hw_queues(ctrl->ctrl.admin_q, true);
> +	if (ctrl->ctrl.state != NVME_CTRL_NEW) {
> +		blk_mq_unquiesce_queue(ctrl->ctrl.admin_q);
> +		blk_mq_kick_requeue_list(ctrl->ctrl.admin_q);
> +	}
>   
>   	ret = nvmf_connect_admin_queue(&ctrl->ctrl);
>   	if (ret)
> @@ -2474,7 +2476,7 @@ nvme_fc_delete_association(struct nvme_fc_ctrl *ctrl)
>   	 * use blk_mq_tagset_busy_itr() and the transport routine to
>   	 * terminate the exchanges.
>   	 */
> -	blk_mq_stop_hw_queues(ctrl->ctrl.admin_q);
> +	blk_mq_quiesce_queue(ctrl->ctrl.admin_q);
>   	blk_mq_tagset_busy_iter(&ctrl->admin_tag_set,
>   				nvme_fc_terminate_exchange, &ctrl->ctrl);
>   

Reviewed-By: James Smart <james.smart at broadcom.com>