Re: [PATCH] vlan: enable GRO if real_dev supports it

[Brandon Philips <bphilips@suse.de>]

On 19:08 Wed 15 Sep 2010, Eric Dumazet wrote:
> Le mercredi 15 septembre 2010 à 09:37 -0700, Brandon Philips a écrit :
> > Currently vlan devices don't have GRO by default as none of the Ethernet
> > drivers add NETIF_F_GRO to their vlan_features.
> > 
> > As GRO is a software feature just propogate GRO from the real_dev in the
> > vlan core. There is no need to have the drivers each add NETIF_F_GRO to
> > their vlan_features.
> > 
> > Signed-off-by: Brandon Philips <bphilips@suse.de>
> > ---
> >  net/8021q/vlan_dev.c |    1 +
> >  1 files changed, 1 insertions(+), 0 deletions(-)
> > 
> > diff --git a/net/8021q/vlan_dev.c b/net/8021q/vlan_dev.c
> > index 3bccdd1..6fbc445 100644
> > --- a/net/8021q/vlan_dev.c
> > +++ b/net/8021q/vlan_dev.c
> > @@ -735,6 +735,7 @@ static int vlan_dev_init(struct net_device *dev)
> >  					  (1<<__LINK_STATE_DORMANT))) |
> >  		      (1<<__LINK_STATE_PRESENT);
> >  
> > +	dev->features |= real_dev->features & NETIF_F_GRO;
> >  	dev->features |= real_dev->features & real_dev->vlan_features;
> >  	dev->gso_max_size = real_dev->gso_max_size;
> >  
> 
> Hmm, this is only part of a generic solution.
> 
> If I enable gro with "ethtool -K eth0 gro on", should we propagate GRO
> on vlan eth0.555 ?

That works fine as far as I can see. I don't think it should go the
other way though. 

Cheers, Brandon