From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ben Hutchings Subject: RE: [RFC PATCH 1/4] net: Add support to netdev ops for changing hardware queue MAC and VLAN filters Date: Mon, 23 Nov 2009 13:22:50 +0000 Message-ID: <1258982570.2845.8.camel@achroite.uk.solarflarecom.com> References: <20091117214923.15119.98918.stgit@localhost.localdomain> <1258573987.2780.20.camel@achroite.uk.solarflarecom.com> <1258586065.2780.31.camel@achroite.uk.solarflarecom.com> <1258642493.2837.8.camel@achroite.uk.solarflarecom.com> <1258657155.2837.10.camel@achroite.uk.solarflarecom.com> Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Cc: "Kirsher, Jeffrey T" , "davem@davemloft.net" , "shemminger@vyatta.com" , "netdev@vger.kernel.org" , "gospo@redhat.com" To: "Williams, Mitch A" Return-path: Received: from mail.solarflare.com ([216.237.3.220]:55930 "EHLO exchange.solarflare.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751992AbZKWNWv (ORCPT ); Mon, 23 Nov 2009 08:22:51 -0500 In-Reply-To: Sender: netdev-owner@vger.kernel.org List-ID: On Thu, 2009-11-19 at 12:34 -0700, Williams, Mitch A wrote: > >From: Ben Hutchings [mailto:bhutchings@solarflare.com] > >Sent: Thursday, November 19, 2009 10:59 AM > > >> Please explain specifically what you perceive to be the difference > >between: > >> > >> $ ip link set eth1 queue 1 mac > >> $ ip link set eth1 queue 1 vlan > >> > >> and > >> > >> $ ip link set eth1 queue 1 mac vlan > >> > >> The two filter types are, in my mind, completely orthogonal. You can > >> have one, or the other, or both, or neither. What do we gain by > >> glomming both options on one command line? And is this worth the > >> tradeoff of more complex code? > > > >I think you need to state clearly what semantics you are now proposing > >before I can make any judgement on them. > > > > OK, now I'm really confused, Ben. It seems that we are both asking > each other the same question. > > What I'm proposing is really the same as we have now for single-queue > devices: > > - A MAC filter is enabled by default. If you want to change the MAC > address, you use a tool (ip or ifconfig) to change it. > > - A VLAN filter is not enabled by default. If you want to filter on > VLANs, then you load the 8021q module, and enable a filter. This doesn't seem quite the same to me, but I'll not argue this. > The MAC filter is configured completely separately from the VLAN > filter. Either one can be changed without affecting the other one and, > in fact, you use two different tools to do these operations. > > For SR-IOV VF devices, my proposed changes implement exactly the same > thing. You use one command to change the MAC address. You use > another command to change the VLAN filter. Changing one does not > affect the other. > > In this case, we use the same tool for both operations, but they're > still separate operations. This makes some sense, and I accept that it's rather different from filtering for delivery to the host. > N.B. > The major difference in VLAN filtering is that this implementation > allows the VF to participate in only one VLAN, and the filter is > applied independently of the VF driver. So you can put a specific VM > on a VLAN without its knowledge. If you want the VM to have more > intelligent VLAN filtering, you don't use this filter, and you load > 8021q in the VM and set your filters there. How does this interact with use of multiple queues within a single function? Are the specified queue numbers really interpreted as RX queue indices or as function numbers? Ben. -- Ben Hutchings, Senior Software Engineer, Solarflare Communications Not speaking for my employer; that's the marketing department's job. They asked us to note that Solarflare product names are trademarked.