From mboxrd@z Thu Jan  1 00:00:00 1970
From: ebiederm@xmission.com (Eric W. Biederman)
Subject: Re: [PATCH 02/11] vfs: More precise tests in d_invalidate
Date: Sat, 15 Feb 2014 15:39:19 -0800
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Cc: Al Viro <viro@zeniv.linux.org.uk>,
	"Serge E. Hallyn" <serge@hallyn.com>,
	Linux-Fsdevel <linux-fsdevel@vger.kernel.org>,
	Kernel Mailing List <linux-kernel@vger.kernel.org>,
	Andy Lutomirski <luto@amacapital.net>,
	Rob Landley <rob@landley.net>,
	Miklos Szeredi <miklos@szeredi.hu>,
	Christoph Hellwig <hch@infradead.org>,
	Karel Zak <kzak@redhat.com>,
	"J. Bruce Fields" <bfields@fieldses.org>
To: Linus Torvalds <torvalds@linux-foundation.org>
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In-Reply-To: <87a9ds55av.fsf@xmission.com> (Eric W. Biederman's message of
	"Sat, 15 Feb 2014 15:23:20 -0800")
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List-Id: linux-fsdevel.vger.kernel.org

ebiederm@xmission.com (Eric W. Biederman) writes:

> But when shrink_dcache_parent and check_submounts_and_drop are
> effectiely the same function I can't possibly see how you can argue how
> the locking has changed or that I am trying to hide things.

And in particular the only locking change that I can see at all is that
d_walk takes read_seqbegin_or_lock before checking the if the d_subdirs
list is empty, which is just an extra cache line read.

Which in practical terms appears like I have removed unnecessary special
cases in favor less code.  Which I think if anything should perform
better just because there is less code to run, and what is happening is
less obfuscated.

Eric