Re: [RFC PATCH net-next 2/3] flow_offload: restore ability to collect separate stats per action

[Edward Cree <ecree@solarflare.com>]

On 08/05/2019 15:02, Jamal Hadi Salim wrote:
> The lazy thing most people have done is essentially assume that
> there is a stat per filter rule...
> I wouldnt call it the 'the right thing'
Yup, that's why I'm trying to not do that ;-)

> Yes, the index at tc semantics level is per-action type.
> So "mirred index 1" and "drop index 1" are not the same stats counter.
Ok, then that kills the design I used here that relied entirely on the
 index to specify counters.
I guess instead I'll have to go with the approach Pablo suggested,
 passing an array of struct flow_stats in the callback, thus using
 the index into that array (which corresponds to the index in
 f->exts->actions) to identify different counters.
Which means I will have to change all the existing drivers, which will
 largely revert (from the drivers' perspective) the change when Pablo
 took f->exts away from them — they will go back to calling something
 that looks a lot like tcf_exts_stats_update().
However, that'll mean the API has in-tree users, so it might be
 considered mergeable(?)

-Ed