Re: [PATCH net-next 1/3] flow_offload: allow user to offload tc action to net device

[Simon Horman <simon.horman@corigine.com>]

On Tue, Aug 03, 2021 at 09:01:45AM -0400, Jamal Hadi Salim wrote:
> On 2021-08-03 8:31 a.m., Simon Horman wrote:
> > On Tue, Aug 03, 2021 at 07:45:13AM -0400, Jamal Hadi Salim wrote:
> 
> 
> > Thanks, I will look into this. But it would make my life slightly easier if
> > 
> > a) You could be more specific about what portion of cls_api you are
> >     referring to.
> > b) Constrained comments to a topic to a single sub-thread.
> > 
> 
> Context, this was on the comment i made on 2/3 here:
> 
> -----
> -        ret = tcf_del_notify(net, n, actions, portid, attr_size, extack);
> +        tcf_action_offload_cmd_pre(actions, FLOW_ACT_DESTROY, extack,
> &fl_act);
> +        ret = tcf_del_notify(net, n, actions, portid, attr_size, extack,
> &fallback_num);
> +        tcf_action_offload_del_post(fl_act, actions, extack, fallback_num);
>           if (ret)
>               goto err;
> ----
> 
> where a notification goes to user space to say "success" but hardware
> update fails.
> 
> If you look at fl_change() which does the offload you'll see that it
> returns err on any of sw or hw failure (depending on request).
> Notification of success is done in cls_api.c - example for
> creating/replacing with this snippet:
> 
> ---
>         err = tp->ops->change(net, skb, tp, cl, t->tcm_handle, tca, &fh,
>                               flags, extack);
>         if (err == 0) {
>                 tfilter_notify(net, skb, n, tp, block, q, parent, fh,
>                                RTM_NEWTFILTER, false, rtnl_held);
>                 tfilter_put(tp, fh);
>                 /* q pointer is NULL for shared blocks */
>                 if (q)
>                         q->flags &= ~TCQ_F_CAN_BYPASS;
>         }
> ---

Thanks for the context Jamal, much appreciated.