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Date: Wed, 21 Jan 2015 23:06:39 +1100
From: Anton Blanchard <anton@samba.org>
To: Arnd Bergmann <arnd@arndb.de>
Subject: Re: [PATCH 1/2] powerpc: Add 64bit optimised memcmp
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Hi Arnd,

> Would it help to also add a way for an architecture to override
> memcmp_pages() with its own implementation? That way you could
> skip the unaligned part, hardcode the loop counter and avoid the
> preempt_disable() in kmap_atomic().

Good idea. We could also have a generic implementation that did long
comparisons, so everyone would get a decent speed up.

Anton