From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [RFC] vxlan: use ether header as fallback hash
Date: Thu, 04 Oct 2012 19:07:56 +0200
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Cc: Jesse Gross <jesse@nicira.com>, davem@davemloft.net,
	netdev@vger.kernel.org
To: Stephen Hemminger <shemminger@vyatta.com>
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On Thu, 2012-10-04 at 09:43 -0700, Stephen Hemminger wrote:
> On Thu, 4 Oct 2012 09:27:14 -0700
> Jesse Gross <jesse@nicira.com> wrote:

> > > +static u16 vxlan_flow_hash(struct sk_buff *skb)
> > > +{
> > > +       u16 hash = skb_get_rxhash(skb);
> > > +
> > > +       if (!hash)
> > > +               hash = jhash(skb->data, 3, skb->protocol);
> > 
> > Shouldn't this be jhash2 for words?
> 
> No. for a couple of reasons. First, the ethernet header may not be aligned.
> Second we want to get source/destination and type.  The source/destination
> is 12 bytes (3 words) and the ether type is already in skb->protocol.

jhash(skb->data, 12, initval)