Re: [dpdk-dev] Does I210 NIC support Flow director filters?

[Bruce Richardson <bruce.richardson@intel.com>]

On Fri, Jan 16, 2015 at 11:42:42AM -0500, Kamraan Nasim wrote:
> Hi Bruce,
> Perhaps this can be worked around by setting  rx_drop_en in the
> rte_eth_rxconf <http://dpdk.org/doc/api/structrte__eth__rxconf.html> and
> using small values for number of rx descripters so that the NIC drops when
> it is out of RX descriptors for that queue?
> 
> As long as NIC can still provide q_ipackets/q_errors then this might be
> faster than doing a RX in software and drop.
> 
> --Kam

Yes, so long as packets dropped for that queue are counted against that queue,
then yes.

/Bruce

> 
> On Fri, Jan 16, 2015 at 5:56 AM, Bruce Richardson <
> bruce.richardson@intel.com> wrote:
> 
> > On Thu, Jan 15, 2015 at 08:06:52PM -0500, Kamraan Nasim wrote:
> > > >>> update the RSS RETA table so that traffic doesn't get sent
> > > >> to that queue via RSS. Is that what you are asking?
> > >
> > > Thanks Bruce, that's exactly it.  Basically each filter will forward
> > > traffic to a unique RSS queue which can allow me to calculate filter
> > match
> > > statistics for that queue(or filter). At that point I would like to drop
> > > the filtered packet. Is there any way to drop the filtered packet in the
> > > RSS queue without doing a rte_eth_rx_burst() and dropping it then?
> > >
> > > --Kam
> > >
> > I don't believe there is any other way to drop them from the queue other
> > than
> > RX and drop. It's not the most efficient way to do so (since you have to
> > allocate,
> > fill and free an mbuf), but it's the only way that an app can do so without
> > adding new functions to the driver(s).
> >
> > /Bruce
> >