From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH net-next-2.6] inetpeer: various changes
Date: Mon, 14 Jun 2010 23:13:31 -0700 (PDT)
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From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Tue, 15 Jun 2010 07:35:21 +0200

> Try to reduce cache line contentions in peer management, to reduce IP
> defragmentation overhead.
> 
> - peer_fake_node is marked 'const' to make sure its not modified.
>   (tested with CONFIG_DEBUG_RODATA=y)
> 
> - Group variables in two structures to reduce number of dirtied cache
> lines. One named "peers" for avl tree root, its number of entries, and
> associated lock. (candidate for RCU conversion)
> 
> - A second one named "unused_peers" for unused list and its lock 
> 
> - Add a !list_empty() test in unlink_from_unused() to avoid taking lock
> when entry is not unused.
> 
> - Use atomic_dec_and_lock() in inet_putpeer() to avoid taking lock in
> some cases.
> 
> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>

Applied.