From mboxrd@z Thu Jan  1 00:00:00 1970
From: Stephen Hemminger <shemminger@vyatta.com>
Subject: Re: [PATCH net-next-2.6] ipv4: speedup inet_dump_ifaddr()
Date: Thu, 12 Nov 2009 09:12:21 -0800
Message-ID: <20091112091221.3d523253@nehalam>
References: <4AFC1798.1060501@gmail.com>
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Cc: "David S. Miller" <davem@davemloft.net>,
	Linux Netdev List <netdev@vger.kernel.org>
To: Eric Dumazet <eric.dumazet@gmail.com>
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On Thu, 12 Nov 2009 15:11:36 +0100
Eric Dumazet <eric.dumazet@gmail.com> wrote:

> When handling large number of netdevices, inet_dump_ifaddr()
> is very slow because it has O(N^2) complexity.
> 
> Instead of scanning one single list, we can use the NETDEV_HASHENTRIES
> sub lists of the dev_index hash table, and RCU lookups.
> 
> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>

You might be able to make RCU critical section smaller by moving
it into loop.

Acked-by: Stephen Hemminger <shemminger@vyatta.com>