Re: [Qemu-devel] [PATCH v2 05/18] xen: add xenstore watcher infrastructure

[Anthony PERARD]

On Thu, Dec 06, 2018 at 03:08:31PM +0000, Paul Durrant wrote:
> @@ -36,6 +54,12 @@ static void xen_block_unrealize(XenDevice *xendev, Error 
> **errp)
>  
>      trace_xen_block_unrealize(type, vdev->disk, vdev->partition);
>  
> +    /* Disconnect from the frontend in case this has not already happened */
> +    xen_block_disconnect(xendev, &local_err);
> +    if (local_err) {
> +        error_propagate(errp, local_err);

If xen_block_disconnect fails, local_err is going to be reuse below. If
it's fine to try unrealize, then `local_err=NULL` is probably enough.

> +    }
> +
>      if (blockdev_class->unrealize) {
>          blockdev_class->unrealize(blockdev, &local_err);
>          if (local_err) {

[...]

> +static void xen_bus_remove_watch(XenBus *xenbus, XenWatch *watch,
> +                                 Error **errp)
> +{
> +    Error *local_err = NULL;
> +
> +    trace_xen_bus_remove_watch(watch->node, watch->key, watch->token);
> +
> +    xs_node_unwatch(xenbus->xsh, watch->node, watch->key, watch->token,
> +                    &local_err);

You could simply pass `errp' directly instead of having `local_err'.

> +
> +    notifier_remove(&watch->notifier);
> +    free_watch(watch);
> +
> +    if (local_err) {
> +        error_propagate(errp, local_err);
> +    }
> +}
> +

-- 
Anthony PERARD