From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Ahern Subject: Re: [PATCH net-next v3] net: ipv4: add support for ECMP hash policy choice Date: Tue, 14 Mar 2017 17:45:06 -0600 Message-ID: <0c0473f7-beab-ea87-6dde-77aa345258ff@cumulusnetworks.com> References: <1489505775-2913-1-git-send-email-nikolay@cumulusnetworks.com> <20170314085502.47d48a4e@xeon-e3> <8088fe5f-0c0b-bdba-4fba-e9e28bbed02e@cumulusnetworks.com> <20170314.114837.619141079617104809.davem@davemloft.net> <20170314132506.6233b1e7@xeon-e3> <20170314144204.20d5c3a5@xeon-e3> <20170314162715.141f1d4b@xeon-e3> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Cc: David Miller , Nikolay Aleksandrov , "netdev@vger.kernel.org" , jkbs@redhat.com, Eric Dumazet , Peter Christensen To: Stephen Hemminger , Roopa Prabhu Return-path: Received: from mail-pf0-f175.google.com ([209.85.192.175]:32966 "EHLO mail-pf0-f175.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750832AbdCNXpJ (ORCPT ); Tue, 14 Mar 2017 19:45:09 -0400 Received: by mail-pf0-f175.google.com with SMTP id w189so726879pfb.0 for ; Tue, 14 Mar 2017 16:45:09 -0700 (PDT) In-Reply-To: <20170314162715.141f1d4b@xeon-e3> Sender: netdev-owner@vger.kernel.org List-ID: On 3/14/17 5:27 PM, Stephen Hemminger wrote: > On Tue, 14 Mar 2017 15:38:40 -0700 > Roopa Prabhu wrote: > >>>>>>> That's what my initial version did, but this was discussed during NetConf in Seville >>>>>>> and it was decided that it's best to make a global sysctl, thus the change. >>>>>> >>>>>> Correct, we discussed this, and we all agreed to only have a sysctl for now. >>>>> >>>>> Why? If you are going to have private discussions please post the rationale >>>>> in public. >>>> >>>> Stephen, is there any reason to have a per ecmp route multipath algo >>>> selection ?. >>>> All platforms have a global multipath selection algo. I also don't see >>>> routing daemons ready or willing to specify a per ecmp route multipath >>>> selection algo attribute. >>> >>> There is no compelling reason to make the attribute per route. But the >>> issue is more that configuration through sysctl's is problematic. It doesn't >>> fit into the standard API paradigm. Sysctl's are like routing patches not >>> part of the real CLI. Trying to trap sysctl's for things like switchedev >>> offload is particularly problematic. I can see the case for either way, >>> and don't have a fixed opinion. >> >> ok. understand the switchdev offload part. It was that way in the past...but >> today you can listen to sysctl updates on the netconf netlink channel. >> it works pretty well. > > Is there another patch to add the NETCONFA_ECMP support? > does userspace care? switchdev uses notifiers for in kernel notification of FIB changes (routes and rules).