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Date: Thu, 25 Mar 2010 09:35:05 -0500 (CDT)
From: Christoph Lameter <cl@linux-foundation.org>
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Subject: Re: [PATCH 02/11] mm,migration: Do not try to migrate unmapped
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On Thu, 25 Mar 2010, Mel Gorman wrote:

> Christoph is opposed to removing it because of cache-hotness issues more
> so than use-after-free concerns. The refcount is needed with or without
> SLAB_DESTROY_BY_RCU.

The issue is only performance. If we can preserve the cache hotness in a
different way (or do things in a completely different manner) then its
fine.