From mboxrd@z Thu Jan  1 00:00:00 1970
From: Stephen Hemminger <shemminger@vyatta.com>
Subject: Re: [PATCH v3 net-next-2.6] netfilter: x_tables: dont block BH
 while reading counters
Date: Thu, 16 Dec 2010 09:57:40 -0800
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Cc: Jesper Dangaard Brouer <hawk@comx.dk>,
	Patrick McHardy <kaber@trash.net>,
	Arnaldo Carvalho de Melo <acme@infradead.org>,
	Steven Rostedt <srostedt@redhat.com>,
	Alexander Duyck <alexander.h.duyck@intel.com>,
	netfilter-devel <netfilter-devel@vger.kernel.org>,
	netdev <netdev@vger.kernel.org>,
	Peter P Waskiewicz Jr <peter.p.waskiewicz.jr@intel.com>
To: Eric Dumazet <eric.dumazet@gmail.com>
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On Thu, 16 Dec 2010 18:53:06 +0100
Eric Dumazet <eric.dumazet@gmail.com> wrote:

> [PATCH v3 net-next-2.6] netfilter: x_tables: dont block BH while reading counters
> 
> Using "iptables -L" with a lot of rules might have a too big BH latency.
> Jesper mentioned ~6 ms and worried of frame drops.
> 
> Switch to a per_cpu seqcount scheme, so that taking a snapshot of
> counters doesnt need to block BH (for this cpu, but also other cpus).
> 
> Reported-by: Jesper Dangaard Brouer <hawk@comx.dk>
> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>

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

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