From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.9 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_NEOMUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id AE353C43381 for ; Mon, 25 Mar 2019 03:26:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6F23C20811 for ; Mon, 25 Mar 2019 03:26:48 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="Xh6ENJJq" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729451AbfCYD0q (ORCPT ); Sun, 24 Mar 2019 23:26:46 -0400 Received: from mail-pf1-f195.google.com ([209.85.210.195]:42317 "EHLO mail-pf1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729298AbfCYD0q (ORCPT ); Sun, 24 Mar 2019 23:26:46 -0400 Received: by mail-pf1-f195.google.com with SMTP id r15so5335879pfn.9 for ; Sun, 24 Mar 2019 20:26:46 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=dMTC8UAjFlRxFXDTYe5mVaBTYP+0NrBSsteC5rizSAA=; b=Xh6ENJJqlyFHU3HavcDpBpIT4bOfEqvcty+pmOZjgeoGAl3Q/EOyTVcNcg1j/95os5 evmN5/Yg8OJx0t228hKQqwVzXHzkpFM38pEEFgykK4O50pw8DrUMNwLV3Mh0s8IyytHn hPAmrbUZsS+BCPx6fL5ILdN2Dnlemzk/esXO0kmPL2kuPxc5bDs1BEDjm/QpN/kjUpZO +M2FPEyMwZzhjevhdkzaOUPi0LDXL4pcYsYDSXNU0rOXiHw+Jmy5evdwu9hw+Qg49DrS +sVtpenn1iCJAhXlDka7ekB/5ixvDPhYS9IzpoE9hVGRmHNvVWB0VF4Hvd5BVTq0vTrF CeXg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=dMTC8UAjFlRxFXDTYe5mVaBTYP+0NrBSsteC5rizSAA=; b=NU7d6pvKzrdywcJSiknTk7y8/CsupIDb4oEIeYr9U+fOF+zzmZxW3lMMYr+bH6zkpp 7d1UGTZVZdBEWZdoEiFUV9uKvZhYhqPbK9xSIlmxBHvoqBB9fS1SrjPwF8nT6xRr/a2L mUkVmPUMMUhC8ywCt8EcxsanPiWPjXVTonpUaxLPauoTs0Jh8WFqzviIChzAx9HNaBJH Qj+fzVwvKyS0DNhL6S5bkFwI58p8P2VvkSZABFjReTnjmi5gqr1/N+vTwvZUvDzYHQ4O sThBPOqChBEZ7UpRwLSvihqtUYKT6BMEwa/Jjwt975f7A5z9MXbuUp2tR0i7Q6W/hmlp e5/w== X-Gm-Message-State: APjAAAUjGQuu4dXIEyLsByNofDNS9FH/zcnkIXX8aLHbvQliIz4DrofV I6mMpVeSNiQcc0t1VdlBPM0= X-Google-Smtp-Source: APXvYqyBXsmS69NlRQBnGLR4ndQ9YHCqAE7ww1Y9Zu0wCCYWztP81vliN69aV5m0fs8jZqPZHIfGpg== X-Received: by 2002:a62:6c43:: with SMTP id h64mr21946917pfc.123.1553484405750; Sun, 24 Mar 2019 20:26:45 -0700 (PDT) Received: from ast-mbp ([2620:10d:c090:180::df31]) by smtp.gmail.com with ESMTPSA id 6sm17181964pfi.53.2019.03.24.20.26.44 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sun, 24 Mar 2019 20:26:45 -0700 (PDT) Date: Sun, 24 Mar 2019 20:26:43 -0700 From: Alexei Starovoitov To: David Ahern Cc: David Miller , netdev@vger.kernel.org, edumazet@google.com Subject: Re: [PATCH net-next] ipv6: Move ipv6 stubs to a separate header file Message-ID: <20190325032641.5xyav65phoeadgye@ast-mbp> References: <20190322130609.11655-1-dsahern@kernel.org> <20190323.214023.610983922857554034.davem@davemloft.net> <20190324035550.b4qjyl5ccfvc3tzi@ast-mbp> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: NeoMutt/20180223 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Sun, Mar 24, 2019 at 06:56:42AM -0600, David Ahern wrote: > > This change also enables many other key features: > 1. IPv4 multipath routes are not evicted just because 1 hop goes down. > 2. IPv6 multipath routes with device only nexthops (e.g., tunnels). > 3. IPv6 nexthop with IPv4 route (aka, RFC 5549) which enables a more > natural BGP unnumbered. > 4. Lower memory consumption for IPv6 FIB entries which has no sharing at > all like IPv4 does. > 5. Allows atomic update of nexthop definitions with a single replace > command as opposed to replacing the N-routes using it. Does kernel work as data plane or control plane in any of the above features ? Sadly the patches allow it to do both, but cumulus doesn't use it for data path. The kernel on control plane cpu is merely a database. And today it doesn't scale when used as a database. The kernel has to be fast as a dataplane but these extra features will slow down the routing by making kernel-as-database scale a bit better. Hence my suggestion in the previous email: use proper database to store routes, nexthops and whatever else necessary to program the asic. The kernel doesn't need to hold this information.