From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH] inet: further fixes of possible seqlock deadlocks
Date: Thu, 28 Nov 2013 18:15:54 -0500 (EST)
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From: Hannes Frederic Sowa <hannes@stressinduktion.org>
Date: Thu, 28 Nov 2013 23:19:26 +0100

> I don't really understand why we distinguish between _BH and plain ICMP stat
> calls then.
> 
> The non-_BH versions deactivate interrupts when updating the per-cpu counter.

This level of distinction exists back in the day where we did per-cpu counters
by hand.  We used to have a BH counter and a non-BH counter for each statistic
and it really helped performance wise.

These days most of that may not be so relevant any more.