[dm-devel] [PATCH 5/7] Fix set_no_path_retry() regression

[Martin Wilck]

Hi Ben,

On Wed, 2018-02-07 at 16:49 -0600, Benjamin Marzinski wrote:
> commit 0f850db7fceb6b2bf4968f3831efd250c17c6138 "multipathd: clean up
> set_no_path_retry" has a bug in it. It made set_no_path_retry
> never reset mpp->retry_ticks, even if the device was in recovery
> mode,
> and there were valid paths. This meant that adding new paths didn't
> remove a device from recovery mode, and queueing could get disabled,
> even while there were valid paths. This patch fixes that.
> 
> Signed-off-by: Benjamin Marzinski <bmarzins at redhat.com>
> ---
>  libmultipath/structs_vec.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/libmultipath/structs_vec.c b/libmultipath/structs_vec.c
> index fbab61f..0de2221 100644
> --- a/libmultipath/structs_vec.c
> +++ b/libmultipath/structs_vec.c
> @@ -343,9 +343,10 @@ static void set_no_path_retry(struct multipath
> *mpp)
>  			dm_queue_if_no_path(mpp->alias, 1);
>  		break;
>  	default:
> -		if (mpp->nr_active > 0)
> +		if (mpp->nr_active > 0) {
> +			mpp->retry_tick = 0;
>  			dm_queue_if_no_path(mpp->alias, 1);
> -		else if (is_queueing && mpp->retry_tick == 0)
> +		} else if (is_queueing && mpp->retry_tick == 0)
>  			enter_recovery_mode(mpp);
>  		break;
>  	}

Please explain why it's sufficient to do this in the "default" case
only. Before 0f850db7, set_no_path_retry() reset retry_tick for any
value of no_path_retry.

Martin

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