Subject: Re: [PATCH v3 net-next-2.6] netfilter: x_tables: dont block BH while reading counters

From: Stephen Hemminger <[email-masked]>
Date: Thu, 16 Dec 2010 09:57:40 -0800

On Thu, 16 Dec 2010 18:53:06 +0100
Eric Dumazet <[email-masked]> 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 <[email-masked]>
> Signed-off-by: Eric Dumazet <[email-masked]>

Acked-by: Stephen Hemminger <[email-masked]>

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