From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH net-next] netns: reorder fields in struct net
Date: Sun, 17 Oct 2010 13:49:31 -0700 (PDT)
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From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Thu, 14 Oct 2010 17:56:18 +0200

> In a network bench, I noticed an unfortunate false sharing between
> 'loopback_dev' and 'count' fields in "struct net".
> 
> 'count' is written each time a socket is created or destroyed, while
> loopback_dev might be often read in routing code.
> 
> Move loopback_dev in a read mostly section of "struct net"
> 
> Note: struct netns_xfrm is cache line aligned on SMP.
> (It contains a "struct dst_ops")
> Move it at the end to avoid holes, and reduce sizeof(struct net) by 128
> bytes on ia32.
> 
> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>

Applied, thanks Eric.