Re: [PATCH net-next V2] tuntap: hardware vlan tx support

From: David Miller
Date: Sat Jul 27 2013 - 23:09:49 EST

From: Jason Wang <jasowang@xxxxxxxxxx>
Date: Thu, 25 Jul 2013 13:00:33 +0800

> Inspired by commit f09e2249c4f5c7c13261ec73f5a7807076af0c8e (macvtap: restore
> vlan header on user read). This patch adds hardware vlan tx support for
> tuntap. This is done by copying vlan header directly into userspace in
> tun_put_user() instead of doing it through __vlan_put_tag() in
> dev_hard_start_xmit(). This eliminates one unnecessary memmove() in
> vlan_insert_tag() for 802.1ad and 802.1q traffic.
> pktgen test shows about 20% improvement for 802.1q traffic:
> Before:
> 662149pps 317Mb/sec (317831520bps) errors: 0
> After:
> 801033pps 384Mb/sec (384495840bps) errors: 0
> Cc: Basil Gor <basil.gor@xxxxxxxxx>
> Cc: Michael S. Tsirkin <mst@xxxxxxxxxx>
> Signed-off-by: Jason Wang <jasowang@xxxxxxxxxx>

Applied, thanks Jason.
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