Re: [PATCH 1/2] nvme-fc: Update hardware queues before using them

[Ming Lei]

On Fri, Jun 25, 2021 at 12:16:48PM +0200, Daniel Wagner wrote:
> In case the number of hardware queues changes, do the update the
> tagset and ctx to hctx first before using the mapping to recreate and
> connnect the IO queues.
> 
> Signed-off-by: Daniel Wagner <dwagner@xxxxxxx>
> ---
>  drivers/nvme/host/fc.c | 16 ++++++++--------
>  1 file changed, 8 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/nvme/host/fc.c b/drivers/nvme/host/fc.c
> index 8a3c4814d21b..a9645cd89eca 100644
> --- a/drivers/nvme/host/fc.c
> +++ b/drivers/nvme/host/fc.c
> @@ -2951,14 +2951,6 @@ nvme_fc_recreate_io_queues(struct nvme_fc_ctrl *ctrl)
>  	if (ctrl->ctrl.queue_count == 1)
>  		return 0;
>  
> -	ret = nvme_fc_create_hw_io_queues(ctrl, ctrl->ctrl.sqsize + 1);
> -	if (ret)
> -		goto out_free_io_queues;
> -
> -	ret = nvme_fc_connect_io_queues(ctrl, ctrl->ctrl.sqsize + 1);
> -	if (ret)
> -		goto out_delete_hw_queues;
> -
>  	if (prior_ioq_cnt != nr_io_queues) {
>  		dev_info(ctrl->ctrl.device,
>  			"reconnect: revising io queue count from %d to %d\n",
> @@ -2968,6 +2960,14 @@ nvme_fc_recreate_io_queues(struct nvme_fc_ctrl *ctrl)
>  		nvme_unfreeze(&ctrl->ctrl);
>  	}
>  
> +	ret = nvme_fc_create_hw_io_queues(ctrl, ctrl->ctrl.sqsize + 1);
> +	if (ret)
> +		goto out_free_io_queues;
> +
> +	ret = nvme_fc_connect_io_queues(ctrl, ctrl->ctrl.sqsize + 1);
> +	if (ret)
> +		goto out_delete_hw_queues;
> +
>  	return 0;
>  
>  out_delete_hw_queues:
> -- 
> 2.29.2
> 

This way may cause correct hctx_idx to be passed to blk_mq_alloc_request_hctx(), so:

Reviewed-by: Ming Lei <ming.lei@xxxxxxxxxx>


Thanks,
Ming