On Wed, 27 Aug 2014 05:42:09 +0000 "Ouyang, Changchun" <changchun.ouyang at intel.com> wrote:
> > > -----Original Message----- > > From: Stephen Hemminger [mailto:stephen at networkplumber.org] > > Sent: Wednesday, August 27, 2014 12:24 AM > > To: Ouyang, Changchun > > Cc: dev at dpdk.org > > Subject: Re: [RFC 06/10] virtio: use software vlan stripping > > > > On Tue, 26 Aug 2014 08:37:11 +0000 > > "Ouyang, Changchun" <changchun.ouyang at intel.com> wrote: > > > > > Hi Stephen, > > > > > > Would you please describe the use scenario for the front end rx vlan strip > > and tx vlan insertion? > > > In our current implementation, backend will strip vlan tag for RX, and > > > insert > > vlan tag for TX. > > > > > > Thanks > > > Changchun > > > > First, we don't have to do software VLAN strip on our backend if we do this. > > And this way we can always use VLAN insert on transmit. Otherwise you > > have to introduce special case because there is no DPDK API to determine if > > device does or does not do VLAN handling. > > > > How the virtio frontend tell backend whether it has software VLAN strip > feature or not? > It seems no feature bit to negotiate it. > > Thanks > Changchun > All other drivers have VLAN stripping as option under rte_eth_rxmode / hw_vlan_strip. There is negotiation in DPDK, it is strictly ask for feature and either get it or an error. Therefore we went ahead and emulated the feature in software.
