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=-0.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, 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 F41A1C04E30 for ; Mon, 9 Dec 2019 17:42:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CB11020836 for ; Mon, 9 Dec 2019 17:42:35 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="fWcAr3pP" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726614AbfLIRmf (ORCPT ); Mon, 9 Dec 2019 12:42:35 -0500 Received: from mail-qk1-f194.google.com ([209.85.222.194]:38192 "EHLO mail-qk1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725904AbfLIRmf (ORCPT ); Mon, 9 Dec 2019 12:42:35 -0500 Received: by mail-qk1-f194.google.com with SMTP id k6so13827501qki.5; Mon, 09 Dec 2019 09:42:34 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc:content-transfer-encoding; bh=DlAlEZc0H305aiJasyWlE8NinnS6GUDEys3Ccy9M+LM=; b=fWcAr3pPEW/3oxGvUT095JEisSFGMdW1LQD29GFpCt1+P6vUItuK8jw/R3dWd5pY7p JkzP3ihVlHwpTQGR2+zJdA3camyuootBTJNlawefR6HQ771GRYqc/huJs1XpF501z7rN jvQ5vcA6eraem4EVeL9CV3fRuTh0lwVn/bUerTJ7QtN0Mxq7owtjywFSXAkpkaPod135 TrAMhITXBpRTzSO8nTYjF3uNVFLA2Qwrr/B5R2jvAAFoAhOlVwn+8ZCbzMU2PaYX2k+9 feLNx29mbC0hOOZQY7U0FCvcAeu/Qsbni6i10vZS/scASGVfy46Boc2xpT6X/K/dgJwN CK5w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc:content-transfer-encoding; bh=DlAlEZc0H305aiJasyWlE8NinnS6GUDEys3Ccy9M+LM=; b=n7MweM3Vc3+kQFbjjVqSP+KIqlyFH7jck5Hozy0NkKzRMmhcOfDzWyY8WInbZwLQsB H/+MeYz5VfPIQgfCmoyXrOggdgbeuS5lHNcUxdNLo8QwFJLSnFOu8b05LME44jgK+dPa orpWhqzmDFJ5l7Bzi47GS3NcJ54RAWPmTDDu1YKN8A4/MuTDm3+XDay1Qk35RKRku1oq HQWlxWFzqaBniRBY0q1X9nBbgxK0VKp/tfz/sLg4GyU9bcThO0JnP3L/rtLbRvMkZ+68 6epFZhZHqQAok4GIhwVliyCAxSYzVKNqM1D+xCYne9xfzXVQucttRXdnZqx8QUW9MCR0 vvTg== X-Gm-Message-State: APjAAAWjfYLupvr2K3sr17lrzC3HWnQqeTDCFWIBxmDbubJwUVrXH7QQ /nHhGVQmiUEys2PBz0+ZbgCm3SrEwqSVm5IGTfg= X-Google-Smtp-Source: APXvYqwYwiTtpVKXund9GsVQS6rtyIblmhcL5g15p9UVk9itaQ7tmMGaz4BhvUiDEV/xWjYh/b6oSM9HjrBSKq/lY6I= X-Received: by 2002:a37:9c0f:: with SMTP id f15mr28796296qke.297.1575913353977; Mon, 09 Dec 2019 09:42:33 -0800 (PST) MIME-Version: 1.0 References: <20191209135522.16576-1-bjorn.topel@gmail.com> <87h829ilwr.fsf@toke.dk> In-Reply-To: <87h829ilwr.fsf@toke.dk> From: =?UTF-8?B?QmrDtnJuIFTDtnBlbA==?= Date: Mon, 9 Dec 2019 18:42:22 +0100 Message-ID: Subject: Re: [PATCH bpf-next v3 0/6] Introduce the BPF dispatcher To: =?UTF-8?B?VG9rZSBIw7hpbGFuZC1Kw7hyZ2Vuc2Vu?= Cc: Netdev , Alexei Starovoitov , Daniel Borkmann , bpf , Magnus Karlsson , "Karlsson, Magnus" , Jonathan Lemon , Edward Cree , =?UTF-8?B?VG9rZSBIw7hpbGFuZC1Kw7hyZ2Vuc2Vu?= , Andrii Nakryiko Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Mon, 9 Dec 2019 at 16:00, Toke H=C3=B8iland-J=C3=B8rgensen wrote: > > Bj=C3=B6rn T=C3=B6pel writes: > [...] > > I like the new version where it's integrated into bpf_prog_run_xdp(); > nice! :) > Yes, me too! Nice suggestion! > > The XDP dispatcher is always enabled, if available, because it helps > > even when retpolines are disabled. Please refer to the "Performance" > > section below. > > Looking at those numbers, I think I would moderate "helps" to "doesn't > hurt" - a difference of less than 1ns is basically in the noise. > > You mentioned in the earlier version that this would impact the time it > takes to attach an XDP program. Got any numbers for this? > Ah, no, I forgot to measure that. I'll get back with that. So, when a new program is entered or removed from dispatcher, it needs to be re-jited, but more importantly -- a text poke is needed. I don't know if this is a concern or not, but let's measure it. Bj=C3=B6rn > -Toke >