From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.0 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3C626C432C3 for ; Tue, 26 Nov 2019 12:15:16 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 08DF92075C for ; Tue, 26 Nov 2019 12:15:16 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="YepJIJT/" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 08DF92075C Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:54062 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iZZkR-0000og-5M for qemu-devel@archiver.kernel.org; Tue, 26 Nov 2019 07:15:15 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:50016) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iZZjm-0000OR-BR for qemu-devel@nongnu.org; Tue, 26 Nov 2019 07:14:35 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1iZZjj-0003SY-9D for qemu-devel@nongnu.org; Tue, 26 Nov 2019 07:14:32 -0500 Received: from us-smtp-2.mimecast.com ([205.139.110.61]:25290 helo=us-smtp-delivery-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1iZZjj-0003Rs-4w for qemu-devel@nongnu.org; Tue, 26 Nov 2019 07:14:31 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1574770470; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=ODQRmH4e73gCnb22Krm046OZAnrWsWskyeHmXfsBuJo=; b=YepJIJT/gF6VujYWV40kG7Nr3/KIU8oyyeP/wzWfOVBmGdWaOVqMH9mHhw/+eETB8fvvAi JSccOC3geiPhmDuR/MwSLBVLVY4etyC1P7jaUshhJcqCaDEEXnlap5bTRJInEaheFWY0NC Zyq/dJs5frcz0OuWkfPRBtrRGHAWQZI= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-240-P9HrIDpQPPSXzoP6-_u1-g-1; Tue, 26 Nov 2019 07:14:26 -0500 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id D642B1005516 for ; Tue, 26 Nov 2019 12:14:25 +0000 (UTC) Received: from work-vm (unknown [10.36.118.59]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 3932A60BEC; Tue, 26 Nov 2019 12:14:19 +0000 (UTC) Date: Tue, 26 Nov 2019 12:14:16 +0000 From: "Dr. David Alan Gilbert" To: Daniel =?iso-8859-1?Q?P=2E_Berrang=E9?= Subject: Re: virtiofsd: Where should it live? Message-ID: <20191126121416.GE2928@work-vm> References: <20191125185021.GB3767@work-vm> <20191126102600.GG556568@redhat.com> MIME-Version: 1.0 In-Reply-To: <20191126102600.GG556568@redhat.com> User-Agent: Mutt/1.12.1 (2019-06-15) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 X-MC-Unique: P9HrIDpQPPSXzoP6-_u1-g-1 X-Mimecast-Spam-Score: 0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable Content-Disposition: inline X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 205.139.110.61 X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: mszeredi@redhat.com, marcandre.lureau@redhat.com, qemu-devel@nongnu.org, stefanha@redhat.com, vgoyal@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" * Daniel P. Berrang=E9 (berrange@redhat.com) wrote: > On Mon, Nov 25, 2019 at 06:50:21PM +0000, Dr. David Alan Gilbert wrote: > > Hi, > > There's been quite a bit of discussion about where virtiofsd, our > > implemenation of a virtiofs daemon, should live. I'd like to get > > this settled now, because I'd like to tidy it up for the next > > qemu cycle. > >=20 > > For reference it's based on qemu's livhost-user+chunks of libfuse. > > It can't live in libfuse because we change enough of the library > > to break their ABI. It's C, and we've got ~100 patches - which > > we can split into about 3 chunks. > >=20 > > Some suggestions so far: > > a) In contrib > > This is my current working assumption; the main objection is it's > > a bit big and pulls in a chunk of libfuse. >=20 > My main objection to 'contrib/' is actually the perceived notions > about what the contrib directory is for. When I see 'contrib/' > code in either QEMU, or other open source projects, my general > impression is that this is largely unsupported code which is just > there as it might be interesting to someone, and doesn't typically > get much ongoing dev attention. >=20 > Parts that are fully supported & actively developed by projects > usually live elsewhere like a src/ or lib/ or tools/ directory. >=20 > This has kind of been the case with QEMU historically, with > the vhost-user-blk, vhost-user-scsi not being real production > quality implementations. Rather they are just technology demos > to show what you might do. vhost-user-gpu/input blurred this > boundary a bit as they're more supported tools, and so I'd > argue contrib/ probably wasn't the right place for them either > in hindsight. >=20 > virtiofsd is definitely different as it is intended to be a > fully production quality supported tool with active dev into > the future IIUC. >=20 > IOW, if we did decide we want it in QEMU, then instead of > '$GIT/contrib/virtiofsd', I'd prefer to see '$GIT/virtiofsd'. I'm not sure it deserves a new top level for such a specific tool. > > b) In a submodule > >=20 > > c) Just separate > >=20 > > Your suggestions/ideas please. My preference is (a). >=20 > What I'm wondering is just how much sharing / overlap of code and concept= s > and community operation there is going otbetween QEMU and virtiofsd. From > the tech POV, IIUC, the main blocker it would need to be in QEMU is becau= se > it links to libvhost-user and we've not declared that to be a stable API > for 3rd party linking. >=20 > Personally I'm always biased towards self-contained apps being in their > own repositories, rather than bundling too much stuff into one repo. You > can see that in the way we've created independant git repos for any libvi= rt > module that didn't need to be part of the main libvirt.git. >=20 > To me the key benefit this gives is flexibility in approach. ie the app > doesn't need to blindly follow every precedent that QEMU has set. It > can instead take the most appropriate path for its needs. For example... >=20 > It could use meson for its build system already. This would be good as > builds will be done in a matter of seconds. For contributors it would > be a much less daunting project to join as it wouldn't be lost in the > firehose of other non-virtiofsd contributions on qemu-devel. >=20 > It doesn't have to follow QEMU's 3-times a year release model, with 6 > week long freeze periods. It can be more agile releasing 6 times a year > with 1 week freezes if desired, I personally think tihs would be quite > desirable for a young project like virtiofsd which is evolving rapidly > as it would get new work available to users much more rapidly. Form virtiofsd's point of view I'm not that worried about the release cycle; Given that features have to go through virtio standardisation, the release ycle is unlikely to be a bottleneck. > It doesn't have to follow QEMU's API stability & deprecation policies. > It could be more flexible in taking non-compatible changes, which again > may be valuable for a young rapidly evolving app. >=20 >=20 >=20 > Anyway to be clear, I'm not a contributor to virtiofsd, nor likely to > be one in the future, so just consider this a personal POV. From QEMU's > POV I don't think it'll matter whether virtiofsd in or out of QEMU git. > It is more about the impact & burden QEMU's dev process & standards might > impose on virtiofsd itself. As a qemu contributor, your opinion is welcome! No need to sit on the fence. > I'm fine with whatever option above is chosen, with the only caveat > being that if its in qemu.git, I don't think it belongs under contrib/ > it should be a top level dir of its own. >=20 Dave > Regards, > Daniel > --=20 > |: https://berrange.com -o- https://www.flickr.com/photos/dberran= ge :| > |: https://libvirt.org -o- https://fstop138.berrange.c= om :| > |: https://entangle-photo.org -o- https://www.instagram.com/dberran= ge :| -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK