From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andi Kleen <andi@firstfloor.org>
Subject: Re: [PATCH V2 1/3] lib: introduce some memory copy macros and     
 functions
Date: Wed, 8 Sep 2010 15:05:19 +0200
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References: <46238.91.60.152.217.1283948365.squirrel@www.firstfloor.org>
	<4C878823.60709@cn.fujitsu.com>
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Cc: Peter Zijlstra <peterz@infradead.org>,
	Ingo Molnar <mingo@redhat.com>,
	Andrew Morton <akpm@linux-foundation.org>,
	"Theodore Ts'o" <tytso@mit.edu>,
	Linux Kernel <linux-kernel@vger.kernel.org>,
	Linux Ext4 <linux-ext4@vger.kernel.org>,
	Linux Btrfs <linux-btrfs@vger.kernel.org>
To: miaox@cn.fujitsu.com
Return-path: <linux-ext4-owner@vger.kernel.org>
In-Reply-To: <4C878823.60709@cn.fujitsu.com>
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On Wed, 08 Sep 2010 20:57:07 +0800
Miao Xie <miaox@cn.fujitsu.com> wrote:

> On Wed, 8 Sep 2010 14:19:25 +0200 (cest), Andi Kleen wrote:
> >
> >> According to the data, the length of the most copies is>=128.
> >
> > Thanks for the data. Large is easier to optimize than small, that's
> > good.
> >
> > Could you also measure how many memsets need the backwards copy?
> > (should be easy to add)
> 
> I think memset doesn't need the backwards copy.

I meant for memmove of course. Obviously memset doesn't need a backwards
copy. That was just the only thing the script didn't measure because
the original version didn't have memmove support.

Your whole thread was about making memmove faster, right?

-Andi
-- 
ak@linux.intel.com -- Speaking for myself only.