Re: [PATCH v2 net-next] net: introduce gro_frag_list_enable sysctl

Ben Hutchings
2013-10-30T19:39:21Z

On Wed, 2013-10-30 at 10:05 +0800, Herbert Xu wrote:
> On Tue, Oct 29, 2013 at 10:02:53PM -0400, David Miller wrote:
> > From: Eric Dumazet <eric.dumazet@gmail.com>
> > Date: Tue, 29 Oct 2013 17:53:48 -0700
> >
> > > So should we apply the first fix to avoid the BUG_ON() ?
> >
> > Please be more specific, are you talking about splitting up
> > this patch in some way?
>
> I think Eric is referring to the patch that removes the BUG_ON
> in skb_segment and deals with the new mega-GRO packets.
>
> I think that's fine for stable, but for the long term we should
> fix it properly as these new meag-GRO packets still retain the
> existing packet boundaries and are trivially segmentable.
>
> If we are indeed able to do that, I doubt we would even need
> the sysctl patch since the GRO performance should be vastly
> superior to the non-GRO case, even for a router/bridge.

I think the change to enable mega-GRO packets should be reverted and
that change should go to stable so that the performance regression for
forwarding is also fixed.

Then it can be re-enabled, with the additional check that there are no
forwarders, in net-next.

Ben.

--
Ben Hutchings, Staff Engineer, Solarflare
Not speaking for my employer; that's the marketing department's job.
They asked us to note that Solarflare product names are trademarked.