From mboxrd@z Thu Jan  1 00:00:00 1970
From: Nick Piggin <npiggin@kernel.dk>
Subject: Re: [PATCH] dcache: faster dentry_cmp()
Date: Fri, 20 Apr 2012 22:06:54 +1000
Message-ID: <20120420120654.GA26894@amd.local0.net>
References: <20120214224526.GA3478@p183.telecom.by>
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Cc: viro@zeniv.linux.org.uk, linux-fsdevel@vger.kernel.org,
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To: Alexey Dobriyan <adobriyan@gmail.com>
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On Wed, Feb 15, 2012 at 01:45:27AM +0300, Alexey Dobriyan wrote:
> 1) consistently use "unsigned int" for dentry name length,
> 2) reuse subtraction result for return value, exact value doesn't matter
>    because function is only used in boolean context,
> 3) use *p++ idiom for even better code.
> 
> All of this results in performance speedup of "git diff"
> which is way out of statistical error (0.4% vs 0.15% of 3 sigma):

Would you have any interest to port this patch on top of
Linus' latest changes there? 0.4% increase is nothing to
sneeze at. There may be some improvements with the
DCACHE_WORD_ACCESS code too.