From mboxrd@z Thu Jan 1 00:00:00 1970 From: John Fastabend Subject: Re: [PATCH net-next] net: Add phys_port identifier to struct net_device and export it to sysfs Date: Fri, 28 Jun 2013 09:33:45 -0700 Message-ID: <51CDBAE9.1020807@gmail.com> References: <20130617181004.GA1364@fedora-17-guest.dell.com> <51BF59D8.10806@gmail.com> <1371656194.1956.25.camel@bwh-desktop.uk.level5networks.com> <1371670481.1956.105.camel@bwh-desktop.uk.level5networks.com> <51C4892B.8000806@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Cc: bhutchings@solarflare.com, netdev@vger.kernel.org, john.r.fastabend@intel.com To: Narendra_K@Dell.com Return-path: Received: from mail-gh0-f170.google.com ([209.85.160.170]:59421 "EHLO mail-gh0-f170.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751845Ab3F1QeD (ORCPT ); Fri, 28 Jun 2013 12:34:03 -0400 Received: by mail-gh0-f170.google.com with SMTP id z10so908214ghb.29 for ; Fri, 28 Jun 2013 09:34:02 -0700 (PDT) In-Reply-To: Sender: netdev-owner@vger.kernel.org List-ID: [...] >> >> Also, do you think this will be primarily useful for partitioning devices that >> expose multiple physical functions? Or do you see a use case for SR-IOV with >> virtual functions as well. The pyhs_port attribute provides a common >> interface for both cases which is good I suppose in the VF case however the >> host can already learn this. I gather from your original post here that you are >> aware of all this. >> > > John, I think it will be useful in the SRIOV scenario also when more than one VF from two NICs are assigned to the guest. phys_port would be helpful in choosing the correct slave interfaces when host details are not available. OK. But I'm not sure why you would assign two VFs from the same NIC to a guest? This doesn't seem like a good configuration for failover because if one VF fails it seems likely both will fail. Maybe there are some benefits for load balancing? Or my assumption both VFs will fail is wrong. Anyways it does seem useful in the partitioning case with multiple physical functions. .John -- John Fastabend Intel Corporation