Re: [PATCH wpan-next v2 11/11] net: mac802154: Add a warning in the slow path

[Alexander Aring <aahringo@redhat.com>]

Hi,

On Thu, May 12, 2022 at 10:34 AM Miquel Raynal
<miquel.raynal@bootlin.com> wrote:
>
> In order to be able to detect possible conflicts between the net
> interface core and the ieee802154 core, let's add a warning in the slow
> path: we want to be sure that whenever we start an asynchronous MLME
> transmission (which can be fully asynchronous) the net core somehow
> agrees that this transmission is possible, ie. the device was not
> stopped. Warning in this case would allow us to track down more easily
> possible issues with the MLME logic if we ever get reports.
>
> Unlike in the hot path, such a situation cannot be handled.
>
> Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
> ---
>  net/mac802154/tx.c | 25 +++++++++++++++++++++++++
>  1 file changed, 25 insertions(+)
>
> diff --git a/net/mac802154/tx.c b/net/mac802154/tx.c
> index a3c9f194c025..d61b076239c3 100644
> --- a/net/mac802154/tx.c
> +++ b/net/mac802154/tx.c
> @@ -132,6 +132,25 @@ int ieee802154_sync_and_hold_queue(struct ieee802154_local *local)
>         return ret;
>  }
>
> +static bool ieee802154_netif_is_down(struct ieee802154_local *local)
> +{
> +       struct ieee802154_sub_if_data *sdata;
> +       bool is_down = false;
> +
> +       rcu_read_lock();
> +       list_for_each_entry_rcu(sdata, &local->interfaces, list) {
> +               if (!sdata->dev)
> +                       continue;
> +
> +               is_down = !(sdata->dev->flags & IFF_UP);

Is there not a helper for this flag?

- Alex