From mboxrd@z Thu Jan  1 00:00:00 1970
From: Cyrill Gorcunov <gorcunov@gmail.com>
Subject: Re: [RFC] fs, proc: Introduce the /proc/<pid>/map_files/ directory v2
Date: Fri, 26 Aug 2011 10:58:57 +0400
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Cc: Vasiliy Kulikov <segoon@openwall.com>,
	Nathan Lynch <ntl@pobox.com>,
	Oren Laadan <orenl@cs.columbia.edu>,
	Daniel Lezcano <dlezcano@fr.ibm.com>,
	Andrew Morton <akpm@linux-foundation.org>,
	Pavel Emelyanov <xemul@parallels.com>,
	linux-kernel@vger.kernel.org,
	James Bottomley <jbottomley@parallels.com>,
	LINUXFS-ML <linux-fsdevel@vger.kernel.org>,
	containers@lists.osdl.org, Zan Lynx <zlynx@acm.org>,
	Andi Kleen <andi@firstfloor.org>
To: Tejun Heo <tj@kernel.org>
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On Thu, Aug 25, 2011 at 11:39:31PM +0200, Tejun Heo wrote:
> Hello,
> 
> On Fri, Aug 26, 2011 at 01:34:59AM +0400, Cyrill Gorcunov wrote:
> > > Unfortunately, not quite as easy as I expected.  The information still
> > > seems redundant but it seems we'll need to change
> > > proc_inode->get_link() to take dentry instead of inode before doing
> > > away with proc_inode->fd, but, at any rate, I don't think this is a
> > > big deal one way or the other.
> > 
> > Hohum... picking up an additional reference to dentry might be dangerous
> > I think. How exactly you imagine we would do that? (without this problem
> > I guess we indeed may drop or rather not change proc-inode).
> 
> Why would you need an extra reference?  All these data structures are
> created dynamically on access and dentry is always available while any
> operation on the inode is in progress so it's guaranteed to be
> available and there's no reason to diddle with reference count.
> Anyways, we can deal with this optimization later, I think.
> 

Hi Tejun, yeah, I somehow missed that you propose to lift up
proc_get_link a bit. Letme try such approach indeed. Thanks!

	Cyrill