From mboxrd@z Thu Jan 1 00:00:00 1970 From: =?utf-8?B?SsO2cm4=?= Engel Subject: Re: + embed-a-struct-path-into-struct-nameidata-instead-of-nd-dentrymnt.pa tch added to -mm tree Date: Tue, 6 Nov 2007 12:30:38 +0100 Message-ID: <20071106113038.GA25953@lazybastard.org> References: <200711052101.lA5L1Q1p019531@imap1.linux-foundation.org> <20071105221021.GC21533@lazybastard.org> <20071106091149.GJ5619@hasse.suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: =?utf-8?B?SsO2cm4=?= Engel , akpm@linux-foundation.org, mm-commits@vger.kernel.org, agruen@suse.de, hch@lst.de, linux-fsdevel@vger.kernel.org, viro@zeniv.linux.org.uk To: Jan Blunck Return-path: Received: from lazybastard.de ([212.112.238.170]:57771 "EHLO longford.lazybastard.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751112AbXKFLfb (ORCPT ); Tue, 6 Nov 2007 06:35:31 -0500 Content-Disposition: inline In-Reply-To: <20071106091149.GJ5619@hasse.suse.de> Sender: linux-fsdevel-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org On Tue, 6 November 2007 10:11:49 +0100, Jan Blunck wrote: > On Mon, Nov 05, J=C3=B6rn Engel wrote: >=20 > > This patch changes some 400 lines, most if not all of which get lon= ger > > and more complicated to read. 23 get sufficiently longer to requir= e an > > additional linebreak. I can't remember complexity being invited in= to > > the kernel without good reasoning, yet the patch description is > > surprisingly low on reasoning: > > > Switch from nd->{dentry,mnt} to nd->path.{dentry,mnt} everywhere. >=20 > I don't measure complexity by lines of code or length of lines. Maybe= I was > not verbose enough in the description, fair. If you have a better metric, please share it. In the paragraph you deleted I explicitly asked for _any_ metric that shows favorable numbers. Lacking numbers, we could only argue about our respective personal taste. > This is a cleanup series. In mostly no case there is a reason why som= eone > would want to use a dentry for itself. This series reflects that fact= in > nameidata where there is absolutly no reason at all. 400+ lines changed in this patch, some 10 in a followup patch that combines dentry/vfsmount assignments into a single path assignment. If your argument above was valid, I would expect more simplifications and fewer complications. Call me a sceptic until further patches show up t= o support your point. > It enforced the correct > order of getting/releasing refcount on pairs. This argument I buy. > It enables us > to do some more cleanups wrt lookup (which are coming later). Please send those patches. I invite cleanups that do clean things up and won't argue against then. ;) > For stacking > support in VFS it is essential to have the pair in = every > place where you want to traverse the stack. True, but unrelated to this patch. > > If churn is the only effect of this, please considere it NAKed agai= n. >=20 > I wonder why you didn't speak up when this series was posted to LKML.= It was > at least posted three times before. I did speak up. Once. If you missed that thread, please forgive me missing those in which the same patch I disapproved of were resent without me on Cc. I'm not categorically against this struct path business. It does have some advantages at first glance. But the patch we're arguing about clearly makes code more complicated and harder to read. We should have more than superficial benefits if we decide to pay such a cost. > Did I break your COW link patches? ;) Nope. No bovine maladies involved. J=C3=B6rn --=20 The competent programmer is fully aware of the strictly limited size of his own skull; therefore he approaches the programming task in full humility, and among other things he avoids clever tricks like the plagu= e. -- Edsger W. Dijkstra - To unsubscribe from this list: send the line "unsubscribe linux-fsdevel= " in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html