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To: "Bryan O'Sullivan" <bos@serpentine.com>
Cc: davem@davemloft.net, arjan@infradead.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] Add memcpy_cachebypass, a copy routine that tries to keep cache pressure down
References: <da0cd816c4cb37c4376b.1152651055@localhost.localdomain>
From: Andi Kleen <ak@suse.de>
Date: 12 Jul 2006 18:15:45 +0200
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Bryan O'Sullivan <bos@serpentine.com> writes:
> + * memcpy_cachebypass - memcpy-compatible copy routine, using streaming loads
> + * @dest: destination address
> + * @src: source address (will not be cached)
> + * @count: number of bytes to copy
> + *
> + * Use streaming loads and normal stores for a special-case copy where
> + * we know we won't be reading the source again, but will be reading the
> + * destination again soon.
> + */

For what CPU did you optimize that function?   Comment missing for that.
Also the comment should state that you're caching the target.
Also I trust you ran it through a comprehensive memcpy-all-cases tester?

-Andi