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Subject: Re: [PATCH 5/6] net: __this_cpu_inc in route.c
From: Eric Dumazet <eric.dumazet@gmail.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Christoph Lameter <cl@linux.com>, Tejun Heo <tj@kernel.org>,
        akpm@linuxfoundation.org, rostedt@goodmis.org,
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        Eric Dumazet <edumazet@google.com>
Date: Wed, 16 Oct 2013 02:22:49 -0700
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On Wed, 2013-10-16 at 10:46 +0200, Peter Zijlstra wrote:

> Are we sure all !x86 implementations will DTRT in that it will increment
> some CPU and not get horribly confused? I suppose it would; but is
> that a guarantee given someplace?

I think we should be fine, these are only stats exposed
on /proc/net/stat/rt_cache

Those 32bit counters were useful when we still had IP route cache.

Most of the fields are no longer incremented.

We eventually could remove them.