To: "Liuweni" <qingshenlwy@gmail.com>
Cc: "linux-kernel" <linux-kernel@vger.kernel.org>,
       "strongzgy" <strongzgy@gmail.com>, "xgr178" <xgr178@163.com>,
       "Liu Hui" <onlyflyer@gmail.com>, "viro" <viro@zeniv.linux.org.uk>,
       "akpm" <akpm@linux-foundation.org>, "jack" <jack@suse.cz>,
       "npiggin" <npiggin@suse.de>,
       "linux-fsdevel" <linux-fsdevel@vger.kernel.org>
Subject: Re: [PATCH 1/3]fs/inode: iunique() Optimize Performance
From: Andi Kleen <andi@firstfloor.org>
References: <200911252209432039291@gmail.com>
Date: Wed, 25 Nov 2009 16:06:22 +0100
In-Reply-To: <200911252209432039291@gmail.com> (Liuweni's message of "Wed, 25 Nov 2009 22:09:45 +0800")
Message-ID: <87pr76ve35.fsf@basil.nowhere.org>
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"Liuweni" <qingshenlwy@gmail.com> writes:

> ---
> move the if condition out the while{}.
> While the function executing, the if 
> condition won't check again and again.
> And this code won't change the function
> of iunique().

Normally compiler automatically move loop invariant code out of loop
bodies. Have you verified that's not the case here?

-Andi

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