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Date: Tue, 26 Aug 2014 09:24:20 -0700
From: Stephen Hemminger <stephen@networkplumber.org>
To: "Ouyang, Changchun" <changchun.ouyang@intel.com>
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Cc: "dev@dpdk.org" <dev@dpdk.org>
Subject: Re: [dpdk-dev] [RFC 06/10] virtio: use software vlan stripping
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On Tue, 26 Aug 2014 08:37:11 +0000
"Ouyang, Changchun" <changchun.ouyang@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.