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Date: Thu, 22 Jan 2015 10:14:48 -0600 (CST)
From: Christoph Lameter <cl@linux.com>
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To: Michal Hocko <mhocko@suse.cz>
cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>,
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        Andrew Morton <akpm@linux-foundation.org>, linux-mm@kvack.org,
        LKML <linux-kernel@vger.kernel.org>
Subject: Re: mmotm: mm-slub-optimize-alloc-free-fastpath-by-removing-preemption-on-off.patch
 is causing preemptible splats
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> I am not sure how to fix this but it sounds like this_cpu_ptr should
> offer the same preempt expectations as other this_cpu_* functions.

One returns a pointer that may not be useful if the context is switched
and the other completes a operationo on an opject.