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From: Andi Kleen <ak@suse.de>
To: Nick Piggin <nickpiggin@yahoo.com.au>
Subject: Re: [PATCH 00/05] robust per_cpu allocation for modules
Date: Mon, 17 Apr 2006 19:10:46 +0200
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On Sunday 16 April 2006 09:06, Nick Piggin wrote:

> I still don't understand what the justification is for slowing down
> this critical bit of infrastructure for something that is only a
> problem in the -rt patchset, and even then only a problem when tracing
> is enabled.

There are actually problems outside -rt. e.g. the Xen kernel was running
into a near overflow and as more and more code is using per cpu variables
others might too.

I'm confident the problem can be solved without adding more variables
though - e.g. in the way rusty proposed.

-Andi