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References: <2fcd155e7b67ba2d41de0a5a0751b3091bf849d8.1267785770.git.andre.goddard@gmail.com> 
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From: =?ISO-8859-1?Q?Andr=E9_Goddard_Rosa?= <andre.goddard@gmail.com>
Date: Tue, 9 Mar 2010 08:58:08 -0300
Message-ID: <b8bf37781003090358y9e28db4v15497543ad14c5fc@mail.gmail.com>
Subject: Re: [PATCH] sysfs/file: move NULL checks to where they make sense and 
	can occur
To: Tejun Heo <tj@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@suse.de>, Alex Chiang <achiang@hp.com>,
       Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>,
       Serge Hallyn <serue@us.ibm.com>, linux-kernel@vger.kernel.org
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Hello,

> On 03/05/2010 07:46 PM, André Goddard Rosa wrote:
>> ... avoiding checking for NULL 2 times in a row when we already have a page.
>>
>> It decreases code size:
>> text    data     bss     dec     hex filename
>> 4246      48    4136    8430    20ee fs/sysfs/file-BEFORE.o
>> 4214      48    4136    8398    20ce fs/sysfs/file-AFTER.o
>>
>> Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com>
>
> Nacked-by: Tejun Heo <tj@kernel.org>
>
> For this level of micro optimization to be meaningful, the code path
> should be *really* *really* hot, which none of sysfs code pats are.
> Whatever is easier to the eyes wins.
>

    Ok Tejun, I understood your point of view.

Thanks,
André