From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem-fT/PcQaiUtIeIZ0/mPfg9Q@public.gmane.org>
Subject: Re: [PATCH net-next] udp: intoduce udp_encap_needed
	static_key
Date: Fri, 13 Apr 2012 13:41:08 -0400 (EDT)
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From: Eric Dumazet <eric.dumazet-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
Date: Thu, 12 Apr 2012 11:05:28 +0200

> Most machines dont use UDP encapsulation (L2TP)
> 
> Adds a static_key so that udp_queue_rcv_skb() doesnt have to perform a
> test if L2TP never setup the encap_rcv on a socket.
> 
> Idea of this patch came after Simon Horman proposal to add a hook on TCP
> as well.
> 
> If static_key is not yet enabled, the fast path does a single JMP .
> 
> When static_key is enabled, JMP destination is patched to reach the real
> encap_type/encap_rcv logic, possibly adding cache misses.
> 
> Signed-off-by: Eric Dumazet <eric.dumazet-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>

Applied to net-next, thanks Eric.

Ban, please incorporate this scheme when you respin your
fixed ipv6 encap/l2tp patches.

Thanks.