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Date: Sat, 7 Sep 2013 19:53:51 +0100
From: Al Viro <viro@ZenIV.linux.org.uk>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Waiman Long <Waiman.Long@hp.com>,
        linux-fsdevel <linux-fsdevel@vger.kernel.org>,
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Subject: Re: [PATCH v3 1/1] dcache: Translating dentry into pathname without
 taking rename_lock
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On Sat, Sep 07, 2013 at 07:07:24PM +0100, Al Viro wrote:

> with these loops turning into
> 	seq = read_seqlock(&rename_lock);
again:
> 	...
> 	if (!seqretry_and_lock(&rename_lock, &seq))
> 		goto again;
> 	...
> 	seqretry_done(&rename_lock);

Forgot the label, sorry.

And I agree that d_lookup() ought to stay as is - this is just about
the ones that try readlock once and then fall back to writer.