From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262354AbVGLEdk (ORCPT ); Tue, 12 Jul 2005 00:33:40 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262341AbVGLEbo (ORCPT ); Tue, 12 Jul 2005 00:31:44 -0400 Received: from mail.kroah.org ([69.55.234.183]:43997 "EHLO perch.kroah.org") by vger.kernel.org with ESMTP id S262340AbVGLEbM (ORCPT ); Tue, 12 Jul 2005 00:31:12 -0400 Date: Mon, 11 Jul 2005 21:27:17 -0700 From: Greg KH To: Tom Zanussi Cc: Karim Yaghmour , akpm@osdl.org, linux-kernel@vger.kernel.org, varap@us.ibm.com, richardj_moore@uk.ibm.com Subject: Re: Merging relayfs? Message-ID: <20050712042717.GB2363@kroah.com> References: <17107.6290.734560.231978@tut.ibm.com> <20050712030555.GA1487@kroah.com> <42D3331F.8020705@opersys.com> <20050712032424.GA1742@kroah.com> <17107.16181.300398.8599@tut.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <17107.16181.300398.8599@tut.ibm.com> User-Agent: Mutt/1.5.8i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jul 11, 2005 at 10:55:33PM -0500, Tom Zanussi wrote: > Greg KH writes: > > On Mon, Jul 11, 2005 at 11:03:59PM -0400, Karim Yaghmour wrote: > > > > > > Greg KH wrote: > > > > What ever happened to exporting the relayfs file ops, and just using > > > > debugfs as your controlling fs instead? As all of the possible users > > > > fall under the "debug" type of kernel feature, it makes more sense to > > > > confine users to that fs, right? > > > > > > Actually, like we discussed the last time this surfaced, there are far > > > more users for relayfs than just debugging. > > > > Based on the proposed users of this fs, I don't see any. What ones are > > you saying are not "debug" type operations? And yes, I consider LTT a > > "debug" type operation :) > > > > The best part of this, is it gives distros and users a consistant place > > to mount the fs, and to know where this kind of thing shows up in the fs > > namespace. > > Makes sense, and I don't see a problem with getting rid of the fs part > of relayfs and letting debugfs take over that role, if debugfs were > there for all potential users. It doesn't sound like it would satisfy > users like LTT and systemtap though, who expect to be available at all > times even on production systems, which wouldn't be the case unless > the distros always shipped with debugfs enabled. They will, the overhead of adding debugfs support is _very_ tiny, only: $ size fs/debugfs/built-in.o text data bss dec hex filename 2257 788 8 3053 bed fs/debugfs/built-in.o So I do not see why you should not just drop your fs part. > > > What we settled on was having relayfs export its file ops so that > > > indeed debugfs users could use it to log things in conjunction with > > > debugfs. > > > > Last I looked, this was not possible. Has this changed in the latest > > version? > > The file operations are all exported, but I haven't actually tried to > use relayfs files in debugfs. Is there something more needed? Shouldn't be. Try it to make sure though :) thanks, greg k-h