Re: [net-next RFC PATCH 5/5] virtio-net: flow director support

[Ben Hutchings <bhutchings@solarflare.com>]

On Tue, 2011-12-06 at 15:25 +0800, Jason Wang wrote:
> On 12/06/2011 04:42 AM, Ben Hutchings wrote:
[...]
> > This is not a proper implementation of ndo_rx_flow_steer.  If you steer
> > a flow by changing the RSS table this can easily cause packet reordering
> > in other flows.  The filtering should be more precise, ideally matching
> > exactly a single flow by e.g. VID and IP 5-tuple.
> >
> > I think you need to add a second hash table which records exactly which
> > flow is supposed to be steered.  Also, you must call
> > rps_may_expire_flow() to check whether an entry in this table may be
> > replaced; otherwise you can cause packet reordering in the flow that was
> > previously being steered.
> >
> > Finally, this function must return the table index it assigned, so that
> > rps_may_expire_flow() works.
> 
> Thanks for the explanation, how about document this briefly in scaling.txt?
[...]

I believe scaling.txt is intended for users/administrators, not
developers.

The documentation for implementers of accelerated RFS is in the comment
for struct net_device_ops and the commit message adding it.  But I
really should improve that comment.

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.