RE: [RFC v2 net-next 4/8] net: mscc: ocelot: add gate and police action offload to PSFP

[Xiaoliang Yang]

Hi Vladimir,

On Wed, Aug 18, 2021 at 23:01:23PM +0800, Vladimir Oltean wrote:
> > @@ -718,6 +734,15 @@ int ocelot_cls_flower_replace(struct ocelot *ocelot,
> int port,
> >  	if (filter->type == OCELOT_VCAP_FILTER_DUMMY)
> >  		return ocelot_vcap_dummy_filter_add(ocelot, filter);
> >
> > +	if (filter->type == OCELOT_PSFP_FILTER_OFFLOAD) {
> > +		kfree(filter);
> > +		if (ocelot->ops->psfp_filter_add)
> > +			return ocelot->ops->psfp_filter_add(ocelot, f);
> > +
> > +		NL_SET_ERR_MSG_MOD(extack, "PSFP chain is not supported in
> HW");
> > +		return -EOPNOTSUPP;
> > +	}
> > +
> >  	return ocelot_vcap_filter_add(ocelot, filter, f->common.extack);  }
> 
> Hmm, I don't really like the idea of allocating an ocelot_vcap_filter which we
> don't need for PSFP filters, just to kfree it later.
> 
> Is it that much more complicated to not allocate it at all in the first place, add
> a bunch of "if" conditions that allocate a VCAP filter only if we are offloading a
> VCAP chain?
> 
> And that means, don't create ocelot_vcap_filter::type ==
> OCELOT_PSFP_FILTER_OFFLOAD, because PSFP filters are not VCAP filters.
The "vcap filter" variable need to be created and use ocelot_flower_parse() to get the type. If the rule is checked as a OCELOT_VCAP_FILTER_DUMMY, the chain 30000 dummy rule will be added in vcap_dummy_filter. And not offload to PSFP filter function. So I created the "vcap filter" and free it before offload to PSFP filter function.

Thanks,
xiaoliang