From mboxrd@z Thu Jan 1 00:00:00 1970 From: Simon Horman Subject: Re: [rfc] Merging the Open vSwitch datapath Date: Tue, 31 Aug 2010 10:38:47 +0900 Message-ID: <20100831013847.GA30077@verge.net.au> References: <20100830062755.GA22396@verge.net.au> <87k4n8ow1r.fsf@benpfaff.org> <43F901BD926A4E43B106BF17856F0755F63A08EE@orsmsx508.amr.corp.intel.com> <20100830183328.GI7629@nicira.com> <43F901BD926A4E43B106BF17856F0755F63A092B@orsmsx508.amr.corp.intel.com> <20100830205907.GM30129@sequoia.sous-sol.org> <20100831004827.GE11594@verge.net.au> <20100831005410.GB30129@sequoia.sous-sol.org> <20100831010103.GH11594@verge.net.au> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: Chris Wright , "Rose, Gregory V" , Ben Pfaff , "netdev@vger.kernel.org" , Stephen Hemminger , Herbert Xu , Arnd Bergmann , David Miller To: Jesse Gross Return-path: Received: from kirsty.vergenet.net ([202.4.237.240]:57043 "EHLO kirsty.vergenet.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756468Ab0HaBix (ORCPT ); Mon, 30 Aug 2010 21:38:53 -0400 Content-Disposition: inline In-Reply-To: Sender: netdev-owner@vger.kernel.org List-ID: On Mon, Aug 30, 2010 at 06:11:30PM -0700, Jesse Gross wrote: > On Mon, Aug 30, 2010 at 6:01 PM, Simon Horman wr= ote: > > On Mon, Aug 30, 2010 at 05:54:10PM -0700, Chris Wright wrote: > >> * Simon Horman (horms@verge.net.au) wrote: > >> > On Mon, Aug 30, 2010 at 01:59:07PM -0700, Chris Wright wrote: > >> > > * Rose, Gregory V (gregory.v.rose@intel.com) wrote: > >> > > > >From: Ben Pfaff [mailto:blp@nicira.com] > >> > > > >On Mon, Aug 30, 2010 at 11:26:17AM -0700, Rose, Gregory V w= rote: > >> > > > >> I just want to put in a plug for the netlink interface. =C2= =A0For NICs with > >> > > > >> EVB we'll need it. > >> > > > > > >> > > > >Off-hand, the main reasons to use Netlink, instead of the e= xisting > >> > > > >character device interface, are that Netlink is easier to e= xtend and > >> > > > >that it should reduce or eliminate the 32-to-64 bit compat = layer > >> > > > >currently in the Open vSwitch tree. > >> > > > >> > > That, plus it's a typical way to do network configuration. =C2= =A0Esp. with > >> > > bi-directional communication. =C2=A0So the userspace bit both = listens to > >> > > netlink messages, like any of the routing daemons or lldpad or= similar > >> > > do, and sends netlink messasges to update driver's flow table. > >> > > > >> > > BTW, this kind of discussion was why Herbert felt strongly aga= inst > >> > > drivers/staging/. =C2=A0He wanted to be sure the interfaces we= re well-defined > >> > > first. > >> > > >> > Is the implication that there is a preference for finalising > >> > the interface (as much as that is possible) before merging? > >> > >> I'll let Herbert chime in, just reminder that was his thought earl= ier > >> this month at LinuxCon. > > > > Thanks, I must confess that had slipped my mind. >=20 > I think it might be worth delaying the merge until we at least have a > starting point. As the userspace interface is such an important > aspect of the code, I don't want to ask people to review code that is > expected to undergo a large change soon (obviously comments are alway= s > welcome at any time). It's probably also more productive to have a > discussion about minor improvements to a proposed interface than a > free-for-all. >=20 > As Ben mentioned, he's working on designing a Netlink-based interface > now. It shouldn't take too long to get a first cut out the door so > we'll have something concrete to discuss. I'll certainly be the firs= t > one to promote the different uses that are possible with Open vSwitch > but I don't want too get bogged down in the details of future feature= s > now. As long as the interface doesn't have serious problems > precluding future work, we can merge the existing code and then move > onto new things. That sounds entirely reasonable.