From mboxrd@z Thu Jan  1 00:00:00 1970
From: Al Viro <viro@ZenIV.linux.org.uk>
Subject: Re: [PATCH] dcache: Translating dentry into pathname without taking
 rename_lock
Date: Thu, 5 Sep 2013 05:20:00 +0100
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Cc: Waiman Long <waiman.long@hp.com>,
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On Wed, Sep 04, 2013 at 07:48:14PM -0700, Linus Torvalds wrote:
>  - use the name length as a maximum
> 
>  - do a byte-at-a-time copy, stopping at a zero (it's going to be
> faster than memchr anyway)
> 
> Then, later on, we can do one that does a word-at-a-time using the
> CONFIG_DCACHE_WORD_ACCESS magic: we know dentry names are always
> word-aligned, and we have an efficient "has_zero()" function for
> finding zero bytes in a word.

Umm...  Dentry names are word-aligned, but the place where we copy them
doesn't have to be.  OTOH, DCACHE_WORD_ACCESS is for architectures where
unaligned stores are fine, so...