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=-0.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=no 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 78524C33CB3 for ; Sat, 1 Feb 2020 16:24:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4A9C3206D3 for ; Sat, 1 Feb 2020 16:24:52 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="DnTQc1mm" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727014AbgBAQYv (ORCPT ); Sat, 1 Feb 2020 11:24:51 -0500 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:57552 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726622AbgBAQYv (ORCPT ); Sat, 1 Feb 2020 11:24:51 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1580574288; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=rVA1xvyvgyakVVp4hFUV7KOikNj3zE1qxsDSM6eeL9k=; b=DnTQc1mm+CHY5CnKWDa0L8T9hWfaoEMaXmsrC7LKebAwLlOTSpv1hmApA8sGrdq58YByRG zjXjeKacU61N+Jk2WQpMnGZO1hLYUiUogMHU1BsFiGsmvAZcG2w5aOOpwi2fZk1hIk8Wg+ AM8XKta5tBE8EQ9qdaUVy5Tg6wEJx+8= Received: from mail-lf1-f70.google.com (mail-lf1-f70.google.com [209.85.167.70]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-209-zEQZsF3qNKSQkAwNPHmcJw-1; Sat, 01 Feb 2020 11:24:46 -0500 X-MC-Unique: zEQZsF3qNKSQkAwNPHmcJw-1 Received: by mail-lf1-f70.google.com with SMTP id j193so1724582lfj.9 for ; Sat, 01 Feb 2020 08:24:46 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:in-reply-to:references:date :message-id:mime-version; bh=rVA1xvyvgyakVVp4hFUV7KOikNj3zE1qxsDSM6eeL9k=; b=GTMv2SzxoC9nEwRkDouunyAe22D4kPVPdBoSz81DbbzyraROaJOnPhJvJQRaAJVffs 4bOP8O4pa4nx/sefwXE0DwwoTN6PgaY45ZwjJkK3fnZc2/wuPbBqLAwqgScvI4QZodWB M3wINU9i+MZFIMaywv0APxw6qUB1wvna3YOQPgOe4rMtDvQn0EiAnzpd/sICF1vgOgX1 tsP0/vHnoYNyYtgAWo1zZujXq6gUlD+upw2fwt/HNH27XJBj30UsqD8/r84sSgXZB2Qf 3K1uBWc+gIOuo1ZPjXryswiAPIPHzIKLnHzEMwjZN8clL2jhOMNGCoWjL3eqmjwtV7Id wUnw== X-Gm-Message-State: APjAAAXU+BMyLI95TEnU4L5mHL/x17HxyJkbJlFroEy7euLbFvCDlxd6 SRNEXUID4A5gK330AJEAvSiiHmlgg7FablbfjdJiexP5wKnx1gp2sbQ466Ne688KL8gvm90/jm6 u1EbdEmLhiYqucH6H X-Received: by 2002:a2e:7e11:: with SMTP id z17mr9177512ljc.279.1580574284877; Sat, 01 Feb 2020 08:24:44 -0800 (PST) X-Google-Smtp-Source: APXvYqx6ldcko3EJxW/8Z861I0HUJBXFWmXKYV3DZFPoz5EmjPIifk68Mi/kkLdXta9lqupvd1orbA== X-Received: by 2002:a2e:7e11:: with SMTP id z17mr9177490ljc.279.1580574284605; Sat, 01 Feb 2020 08:24:44 -0800 (PST) Received: from alrua-x1.borgediget.toke.dk ([85.204.121.218]) by smtp.gmail.com with ESMTPSA id 14sm6221745lfz.47.2020.02.01.08.24.43 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 01 Feb 2020 08:24:43 -0800 (PST) Received: by alrua-x1.borgediget.toke.dk (Postfix, from userid 1000) id 57A311800A2; Sat, 1 Feb 2020 17:24:39 +0100 (CET) From: Toke =?utf-8?Q?H=C3=B8iland-J=C3=B8rgensen?= To: Jakub Kicinski , David Ahern Cc: David Ahern , netdev@vger.kernel.org, prashantbhole.linux@gmail.com, jasowang@redhat.com, davem@davemloft.net, jbrouer@redhat.com, mst@redhat.com, toshiaki.makita1@gmail.com, daniel@iogearbox.net, john.fastabend@gmail.com, ast@kernel.org, kafai@fb.com, songliubraving@fb.com, yhs@fb.com, andriin@fb.com, David Ahern Subject: Re: [PATCH bpf-next 03/12] net: Add IFLA_XDP_EGRESS for XDP programs in the egress path In-Reply-To: <20200128055752.617aebc7@cakuba> References: <20200123014210.38412-1-dsahern@kernel.org> <20200123014210.38412-4-dsahern@kernel.org> <87tv4m9zio.fsf@toke.dk> <335b624a-655a-c0c6-ca27-102e6dac790b@gmail.com> <20200124072128.4fcb4bd1@cakuba> <87o8usg92d.fsf@toke.dk> <1d84d8be-6812-d63a-97ca-ebc68cc266b9@gmail.com> <20200126141141.0b773aba@cakuba> <33f233a9-88b4-a75a-d1e5-fbbda21f9546@gmail.com> <20200127061623.1cf42cd0@cakuba> <252acf50-91ff-fdc5-3ce1-491a02de07c6@gmail.com> <20200128055752.617aebc7@cakuba> X-Clacks-Overhead: GNU Terry Pratchett Date: Sat, 01 Feb 2020 17:24:39 +0100 Message-ID: <87ftfue0mw.fsf@toke.dk> MIME-Version: 1.0 Content-Type: text/plain Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org [ skipping the first part to just comment on the below: ] > I'm weary of partially implemented XDP features, EGRESS prog does us > no good when most drivers didn't yet catch up with the REDIRECTs. I kinda agree with this; but on the other hand, if we have to wait for all drivers to catch up, that would mean we couldn't add *anything* new that requires driver changes, which is not ideal either :/ > And we're adding this before we considered the queuing problem. > > But if I'm alone in thinking this, and I'm not convincing anyone we > can move on :) I do share your concern that this will end up being incompatible with whatever solution we end up with for queueing. However, I don't necessarily think it will: I view the XDP egress hook as something that in any case will run *after* packets are dequeued from whichever intermediate queueing it has been through (if any). I think such a hook is missing in any case; for instance, it's currently impossible to implement something like CoDel (which needs to know how long a packet spent in the queue) in eBPF. -Toke