From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH net-next] net: avoid RCU for NOCACHE dst
Date: Wed, 20 Oct 2010 03:03:08 -0700 (PDT)
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From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Fri, 15 Oct 2010 17:44:11 +0200

> There is no point using RCU for dst we allocate for a very short time
> (used once).
> 
> Change dst_release() to take DST_NOCACHE into account, but also change
> skb_dst_set_noref() to force a refcount increment for such dst.
> 
> This is a _huge_ gain, because we dont waste memory to store xx thousand
> of dsts. Instead of queueing them to RCU, we can free them instantly. 
 ...
> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>

Wonderful, we are now faster without the routing cache. :-)

Applied.