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From: Tejun Heo <tj@kernel.org>
To: "André Goddard Rosa" <andre.goddard@gmail.com>
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
Subject: Re: [PATCH] sysfs/file: move NULL checks to where they make sense and can occur
Date: Tue, 09 Mar 2010 16:38:46 +0900	[thread overview]
Message-ID: <4B95FB06.6070906@kernel.org> (raw)
In-Reply-To: <2fcd155e7b67ba2d41de0a5a0751b3091bf849d8.1267785770.git.andre.goddard@gmail.com>

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.

Thanks.

-- 
tejun

  reply	other threads:[~2010-03-09  7:39 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-03-05 10:46 [PATCH] sysfs/file: move NULL checks to where they make sense and can occur André Goddard Rosa
2010-03-09  7:38 ` Tejun Heo [this message]
2010-03-09 11:58   ` André Goddard Rosa

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