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=-6.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 64A7EC433E2 for ; Tue, 15 Sep 2020 08:47:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 00F7A21D7D for ; Tue, 15 Sep 2020 08:47:57 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="ijHgiMEa" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726208AbgIOIry (ORCPT ); Tue, 15 Sep 2020 04:47:54 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:59402 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726130AbgIOIrs (ORCPT ); Tue, 15 Sep 2020 04:47:48 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1600159667; 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=gHqMMhcef71Vz4nIIhCc753F8Sj6cnpzNuOswe+NHDE=; b=ijHgiMEaxio/304CLIQhvh2Jf5vOeQS4Ld6QHsH+1Uq4JGaH+AHrlQrUo+KXwKV4RxYJgg fhPBThaKH/4cFMWYU0xbYmVAY3cJdCYT3IrrUcmh8iCImvlebpogkACqQljK8CbdugqWH5 5sRZAiSjHukeA7Nb13dBuwjlCOE5CE4= Received: from mail-wm1-f70.google.com (mail-wm1-f70.google.com [209.85.128.70]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-141-bXR2-nRbOGeFjejPhJE9TQ-1; Tue, 15 Sep 2020 04:47:39 -0400 X-MC-Unique: bXR2-nRbOGeFjejPhJE9TQ-1 Received: by mail-wm1-f70.google.com with SMTP id y18so916910wma.4 for ; Tue, 15 Sep 2020 01:47:38 -0700 (PDT) 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=gHqMMhcef71Vz4nIIhCc753F8Sj6cnpzNuOswe+NHDE=; b=Yb9duxS0aeiWWZQD+wArQDpwOklcWFPK9DWA4DnBR92SCQGmCoWDLtoLZI/1i331iR ESGPw5GBY0qVyxewaHkJc/Xxy8uClzHVGabTQUrFTulbVz/7Uk8g4GlP0blqdk+V1dmt +flFG+/tcIhUvrMUrhasXeaA7oGK8rf6gtdiyfyJ3mb+n3ogafkbgpYzTtOqTyj7f4et uJfvTcHq8pVLBKJZDlo5oo0dxfD+Pwc4QTQoyi+rJfbhgFjemLx2CNCTIpmtWYohmq6E vrd2hZ2zV0zlIu22IqLT9/3HHGdVodT7SIOJdTfhOBx8Z7vU/sfpoK+om4zZ0So0De5J Ndww== X-Gm-Message-State: AOAM5313pcLrgwAEl8w/uHzkabSpGZBmA03HHYSFWCKy89KgpEPOLS77 1UL6TW0en/eCoHwOPE9NEb0ydtDKLvrcF4LGKMJ7T3Vcuvcx1Qq+qpe+ktnoKPbpN3AUCnRZxHO AxG8JdrQDD1x3 X-Received: by 2002:adf:e407:: with SMTP id g7mr20040882wrm.349.1600159657884; Tue, 15 Sep 2020 01:47:37 -0700 (PDT) X-Google-Smtp-Source: ABdhPJxbWanePA3VlARamVJW+Nyg1rmLNkw3TQwnaiY4YIqTex+hDI5pSlEWKYWWhGWrf9aw3oq7Gg== X-Received: by 2002:adf:e407:: with SMTP id g7mr20040856wrm.349.1600159657574; Tue, 15 Sep 2020 01:47:37 -0700 (PDT) Received: from alrua-x1.borgediget.toke.dk ([2a0c:4d80:42:443::2]) by smtp.gmail.com with ESMTPSA id u66sm23666792wmg.44.2020.09.15.01.47.36 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 15 Sep 2020 01:47:36 -0700 (PDT) Received: by alrua-x1.borgediget.toke.dk (Postfix, from userid 1000) id 68E401829CB; Tue, 15 Sep 2020 10:47:36 +0200 (CEST) From: Toke =?utf-8?Q?H=C3=B8iland-J=C3=B8rgensen?= To: Maciej =?utf-8?Q?=C5=BBenczykowski?= , Jesper Dangaard Brouer Cc: Jakub Kicinski , bpf , Linux NetDev , Daniel Borkmann , Alexei Starovoitov , John Fastabend Subject: Re: [PATCH bpf-next] bpf: don't check against device MTU in __bpf_skb_max_len In-Reply-To: References: <159921182827.1260200.9699352760916903781.stgit@firesoul> <20200904163947.20839d7e@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com> <20200907160757.1f249256@carbon> <20200914160538.2bd51893@carbon> X-Clacks-Overhead: GNU Terry Pratchett Date: Tue, 15 Sep 2020 10:47:36 +0200 Message-ID: <87ft7jzas7.fsf@toke.dk> MIME-Version: 1.0 Content-Type: text/plain Sender: bpf-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org [ just jumping in to answer this bit: ] > Would you happen to know what ebpf startup overhead is? > How big a problem is having two (or more) back to back tc programs > instead of one? With a jit'ed BPF program and the in-kernel dispatcher code (which avoids indirect calls), it's quite close to a native function call. > We're running into both verifier performance scaling problems and code > ownership issues with large programs... > > [btw. I understand for XDP we could only use 1 program anyway...] Working on that! See my talk at LPC: https://linuxplumbersconf.org/event/7/contributions/671/ Will post a follow-up to the list once the freplace multi-attach series lands. -Toke