From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ben Hutchings Subject: Re: [patch net-next v2 00/15] net: introduce upper device lists and remove dev->master Date: Tue, 14 Aug 2012 21:32:53 +0100 Message-ID: <1344976373.2690.41.camel@bwh-desktop.uk.solarflarecom.com> References: <1344956748-2099-1-git-send-email-jiri@resnulli.us> <20120814201950.GA17781@quad.redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20120814201950.GA17781@quad.redhat.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: bridge-bounces@lists.linux-foundation.org Errors-To: bridge-bounces@lists.linux-foundation.org To: Andy Gospodarek Cc: bridge@lists.linux-foundation.org, ursula.braun@de.ibm.com, john.r.fastabend@intel.com, edumazet@google.com, shemminger@vyatta.com, sean.hefty@intel.com, therbert@google.com, roland@kernel.org, linux-s390@vger.kernel.org, linux-rdma@vger.kernel.org, fubar@us.ibm.com, fbl@redhat.com, hal.rosenstock@gmail.com, Jiri Pirko , faisal.latif@intel.com, blaschka@linux.vnet.ibm.com, sony.chacko@qlogic.com, linux-driver@qlogic.com, xiyou.wangcong@gmail.com, jitendra.kalsaria@qlogic.com, divy@chelsio.com, gregory.v.rose@intel.com, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, kaber@trash.net, joe@perches.com, linux390@de.ibm.com, davem@davemloft.net List-Id: linux-rdma@vger.kernel.org On Tue, 2012-08-14 at 16:19 -0400, Andy Gospodarek wrote: > On Tue, Aug 14, 2012 at 05:05:33PM +0200, Jiri Pirko wrote: > > Hi all. > > > > Recent discussion around > > "[net-next] bonding: don't allow the master to become its slave" > > forced me to think about upper<->lower device connections. > > > > This patchset adds a possibility to record upper device linkage. > > All upper<->lower devices are converted to use this mechanism right after. > > That leads to dev->master removal because this info becomes redundant since > > "unique links" have the same value. > > > > After all changes, there is no longer possible to do: > > "bond->someotherdevice->samebond" > > > > Also I think that drivers like cxgb3, qlcnic, qeth would benefit by this > > in future by being able to get more appropriate info about l3 addresses. > > > > v1->v2: > > - s/unique/master/ better naming + stays closer to the history > > - fixed vlan err goto > > - original patch 15 (WARN_ON change) is squashed into the first patch > > - fixed netdev_unique_upper_dev_get_rcu() case of upper==NULL > I just started to review v1 when v2 came out, but luckily the changes > were not too significant that I need to start all over. > > The first note is that I didn't like the use of the term 'upper' -- it > seems like 'stacked' might be a better alternative as these are stacked > devices. When linking any two devices in a stack, one will be upper and the other lower. The lower device might itself be stacked on top of a further device, so 'stacked' is not a useful distinguishing adjective in variable names. It might be a useful term in the commit messages and kernel-doc, though. > One thing to note is that I don't see any clear changelog that states > the current goals for this. You have stated in several places that it > will no longer be possible to create bonds of bonds, but there are > probably a few more things it might be wise to intentionally outlaw. > > What about teams of teams? Or teams of bonds? Or bonds of teams? > Bonds of vlans? [...] It doesn't disallow bonds of bonds (unless I'm missing something). It disallows loops that involve any or all of those types of stacked devices. Ben. -- Ben Hutchings, Staff Engineer, Solarflare Not speaking for my employer; that's the marketing department's job. They asked us to note that Solarflare product names are trademarked.