From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH] NET : UDP can use sk_hash to speedup lookups
Date: Fri, 09 Feb 2007 15:45:11 -0800 (PST)
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From: Eric Dumazet <dada1@cosmosbay.com>
Date: Fri, 9 Feb 2007 18:44:16 +0100

> In a prior patch, I introduced a sk_hash field (__sk_common.skc_hash)  to let 
> tcp lookups use one cache line per unmatched entry instead of two.
> 
> We can also use sk_hash to speedup UDP part as well. We store in sk_hash the 
> hnum value, and use sk->sk_hash (same cache line than 'next' pointer), 
> instead of inet->num (different cache line)
> 
> Note : We still have a false sharing problem for SMP machines, because 
> sock_hold(sock) dirties the cache line containing the 'next' pointer. Not 
> counting the udp_hash_lock rwlock. (did someone mentioned RCU ? :) )
> 
> Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>

Applied, thanks Eric.