From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [RFC] net: release dst entry in dev_queue_xmit()
Date: Tue, 24 Mar 2009 23:43:54 -0700 (PDT)
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From: Eric Dumazet <dada1@cosmosbay.com>
Date: Fri, 20 Mar 2009 12:40:22 +0100

> I believe we can release dst in dev_queue_xmit(), while cpu cache is
> hot, since caller of dev_queue_xmit() had to hold a reference on dst
> right before. This reduce work to be done by softirq handler, and
> decrease cache misses.
> 

This will break various packet schedulers and classifiers.

Heck sch_sfq.c even uses skb->dst as part of it's flow hash
function :-)