From: Eric Sandeen Subject: Re: [PATCH v2] xfstests: add support for ext4dev FSTYP Date: Fri, 03 Jun 2011 00:06:09 -0500 Message-ID: <4DE86BC1.4080008@redhat.com> References: <1306933012-8666-1-git-send-email-amir73il@users.sourceforge.net> <20110601232804.GL32466@dastard> <4DE7A557.9040608@redhat.com> <7D3F86FA-5AA9-49B0-9AFE-F597E83C07B4@dilger.ca> <20110603003610.GD16306@thunk.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: "Ted Ts'o" , Andreas Dilger , Dave Chinner , xfs@oss.sgi.com, linux-ext4@vger.kernel.org, linux-fsdevel@vger.kernel.org, sergey57@gmail.com, Amir Goldstein To: "Amir G." Return-path: Received: from mx1.redhat.com ([209.132.183.28]:53969 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750890Ab1FCFG1 (ORCPT ); Fri, 3 Jun 2011 01:06:27 -0400 In-Reply-To: Sender: linux-ext4-owner@vger.kernel.org List-ID: On 6/2/11 11:59 PM, Amir G. wrote: > On Fri, Jun 3, 2011 at 3:36 AM, Ted Ts'o wrote: >> On Thu, Jun 02, 2011 at 11:22:53AM -0600, Andreas Dilger wrote: >>> On 2011-06-02, at 8:59 AM, Eric Sandeen wrote: >>>> I don't really mind adding ext4dev to FSTYP case statements, it >>>> -is- something which blkid could, in theory, still return, and >>>> making xfstests cope with that and try to invoke fsck -t ext4dev >>>> doesn't bother me too much. It is sadly an fs type embedded into >>>> a few tools. >>> >>> I'm perfectly OK with using ext4dev as a filesystem type that allows testing >>> changes to ext4 on a system that is already running ext4 as the root fs. >> >> My take on this is that way too much time has been spent this subject. > > No doubt. > >> Being able to use ext4dev is useful, and given that we have all of >> this support in our existing system tools, why not use it to make ext4 >> development more efficient/easy? As a bonus you can build the ext4dev >> as a module, and that means you the compile/edit/debug cycle can be >> much faster since you can avoid doing a reboot, for those >> circumstances where using KVM is not possible/convenient. Personally, >> I normally use KVM these days, but I can imagine situations where >> using ext4dev would be a better way to go. For example, I'd probably >> use KVM on my laptop, but for testing on production servers in a data >> center, I'd probably use ext4dev, for a variety of local deployment >> considerations that's not worth going into here. >> >> That being said, whether or not we modify xfstests seems to be a moot >> point. In order for me to do my bigalloc development, I've been >> patching common.rc so that "/sbin/mkfs.$FSTYP" --> "mkfs.$FSTYP" and >> "/sbin/fsck -t $FSTYP" --> "fsck.$FSTYP". It's a 3 line change. Not >> a big deal. I've been making this change using /bin/ed after >> installing xfstests. So if the XFS folks want to veto this change --- >> who cares? It's not hard to make the change locally in order to make >> xfstests. >> >> On the other hand, given that xfstests is using "mkfs.$FSTYP", I don't >> see why it's so important that it clings to "fsck -t $FSTYP" instead >> of using "fsck.$FSTYP". There's no real benefit to calling the fsck >> driver; it's just an extra fork and exec, and xfstests is being >> inconsistent by insisting on the use of the fsck driver, but not using >> the mkfs driver. >> >> But that being said, hacking xfstests is not hard, and if Dave and/or >> Eric feels strongly about resisting this change, it's not worth a lot >> of time, one way or another.... >> >> - Ted >> > > I blame only myself for not presenting the case correctly. > I made it sound like I am trying to push my own private hack upstream. > Actually, all 10 people involved in snapshot development clone my xfstests > tree from github, so we have no real need for the upstream change. > The reason I was pushing upstream is because I found this feature > so useful, I thought other developers may enjoy it as well. > > Anyone on on this thread not having used ext4dev by next LSF > can come to me to claim his beer ;-) mmm I like beer, I'll see you then! ;) -Eric (tucking this email away for future reference... ;) > Amir.