From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Ahern Subject: Re: [PATCH net] net/ipv6: Revert attempt to simplify route replace and append Date: Wed, 4 Jul 2018 21:01:52 -0600 Message-ID: <7dcb15ac-9089-a323-1beb-2c07a61df242@gmail.com> References: <20180703134302.GB15120@splinter.mtl.com> <20180704211041.GB24525@splinter> <20180705.112935.1655283984550635892.davem@davemloft.net> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Cc: dsahern@kernel.org, netdev@vger.kernel.org, sharpd@cumulusnetworks.com, Thomas.Winter@alliedtelesis.co.nz, petrm@mellanox.com To: David Miller , idosch@mellanox.com Return-path: Received: from mail-pl0-f66.google.com ([209.85.160.66]:36818 "EHLO mail-pl0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753002AbeGEDB4 (ORCPT ); Wed, 4 Jul 2018 23:01:56 -0400 Received: by mail-pl0-f66.google.com with SMTP id a7-v6so545486plp.3 for ; Wed, 04 Jul 2018 20:01:56 -0700 (PDT) In-Reply-To: <20180705.112935.1655283984550635892.davem@davemloft.net> Content-Language: en-US Sender: netdev-owner@vger.kernel.org List-ID: On 7/4/18 8:29 PM, David Miller wrote: > From: Ido Schimmel > Date: Thu, 5 Jul 2018 00:10:41 +0300 > >> We can have the IPv4/IPv6 code only generate a REPLACE / DELETE >> notification for routes that are actually used for forwarding and >> relieve listeners from the need to implement this logic themselves. I >> think this should work. > > Whilst this could reduce the duplication, I worry that in the long > term that this might end up being error prone. > Duplication of data and duplication of logic is not ideal. Especially in this case where the duplication of both is only to handle one case - duplicate routes where only the first is programmed. I suspect it will have to be dealt with at some point (e.g., scaling to a million routes), but right now there are more important factors to deal with - like the rtnl_lock. Something to keep in mind for the future.