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=-6.6 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,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 BDA3DC56201 for ; Wed, 11 Nov 2020 18:29:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6089B2076E for ; Wed, 11 Nov 2020 18:29:46 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="mRJhSKoD" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726361AbgKKS3p (ORCPT ); Wed, 11 Nov 2020 13:29:45 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43532 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725966AbgKKS3p (ORCPT ); Wed, 11 Nov 2020 13:29:45 -0500 Received: from mail-yb1-xb43.google.com (mail-yb1-xb43.google.com [IPv6:2607:f8b0:4864:20::b43]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A99CFC0613D1; Wed, 11 Nov 2020 10:29:43 -0800 (PST) Received: by mail-yb1-xb43.google.com with SMTP id 10so2781344ybx.9; Wed, 11 Nov 2020 10:29:43 -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; bh=QAV7PrwQ2zPY3WXg+djmUbZuDNM+6xgvTGf3s+IjCwQ=; b=mRJhSKoDF5AXhMhWNian1jZhReGbQWqnMrIIJvm19xCJ3cVYGn19xvTOC93IRFInSH LUDlJpcAkIOzew8jlX94JYYp3Uakp6DL5qEEeYniZH+Mzga4QRFoOpKLappEcd1OwWjz N5ThM/dOs8h3gXYsHSaqNzomSSdO9rYKZOtpYOf1ZN5FFhbp/d4YDO1LngkRPcOaW3s3 fKQdgqVyevP1Ydz9tzVehmO4q04EtrhC6tD1ILLZ09Rr0DZ5pcwB3rVJx4D9n15YaL05 2XuoKx4XWB9VjCSlxjnm/K4bmyJNwiQNA/yYDXvU3Hm34TlRwhX5KJ+1KLWjcxqreCnY q86w== 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; bh=QAV7PrwQ2zPY3WXg+djmUbZuDNM+6xgvTGf3s+IjCwQ=; b=L/kYzJfGuroa75uxPwIMufJzG6w7N0pssbNis1ZqmH/mRhiNWHARbWaBFfKgioVz0X hRqkciusgjRL25uhXNiI4FZeUacikNyquNk8Cd8c8sR3MbNWFWLzX/VZ2iJeD6xEbhv/ El3OUzsVlFDag/lNbFswrxHsZWRyBmJP6g3Al9kmdP0FjO8L253JTN5LB4Pj8Y+4mPNV t6Sluy460mZHBt/4ttl4TH7hdSVo91VFgjPvqqlZNYFFaUaBi/wdSpUrRWRVT2gnntXO 6TPwV4LgJCMAGVDrO67zD5oE+Jbki0MoNBBD/TlQF7JvsATkKedWpPVLdBhudIBWRXGT pqew== X-Gm-Message-State: AOAM530jXwxA+TYLTO4I+teok8gxZoCOivw2AleVi6rlfNymhfhX8DGS kYhz4tHNLUfTVbmim050jq1en07ATgKuAbKrKwo= X-Google-Smtp-Source: ABdhPJxTy8SEkZNOHCIA8wwrCI+hbxusQ6mgSzBWahJ+EURieg6YcSQqmccwZztAQNq/htXwhcYk0VfhW8lN5gfOkv8= X-Received: by 2002:a25:7717:: with SMTP id s23mr22662260ybc.459.1605119382963; Wed, 11 Nov 2020 10:29:42 -0800 (PST) MIME-Version: 1.0 References: <20201106052549.3782099-1-andrii@kernel.org> <20201106052549.3782099-5-andrii@kernel.org> <20201111115627.GB355344@kernel.org> <20201111121946.GD355344@kernel.org> In-Reply-To: <20201111121946.GD355344@kernel.org> From: Andrii Nakryiko Date: Wed, 11 Nov 2020 10:29:32 -0800 Message-ID: Subject: Re: [PATCH dwarves 4/4] btf: add support for split BTF loading and encoding To: Arnaldo Carvalho de Melo Cc: Andrii Nakryiko , dwarves@vger.kernel.org, bpf , Kernel Team , Jiri Olsa , Namhyung Kim Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org On Wed, Nov 11, 2020 at 4:19 AM Arnaldo Carvalho de Melo wrote: > > Em Wed, Nov 11, 2020 at 08:56:27AM -0300, Arnaldo Carvalho de Melo escreveu: > > > > The entry for btf_encode/-J is missing, I'll add in a followup patch. > > > > Also I had to fixup ARGP_btf_base to 321 as I added this, to simplify > > the kernel scripts and Makefiles: > > > > $ pahole --numeric_version > > 118 > > $ > > Added this: > > [acme@five pahole]$ git diff > diff --git a/man-pages/pahole.1 b/man-pages/pahole.1 > index 20ee91fc911d4b39..f44c649924383a32 100644 > --- a/man-pages/pahole.1 > +++ b/man-pages/pahole.1 > @@ -181,6 +181,14 @@ the debugging information. > .B \-\-skip_encoding_btf_vars > Do not encode VARs in BTF. > > +.TP > +.B \-J, \-\-btf_encode > +Encode BTF information from DWARF, used in the Linux kernel build process when > +CONFIG_DEBUG_INFO_BTF=y is present, introduced in Linux v5.2. Used to implement > +features such as BPF CO-RE (Compile Once - Run Everywhere). > + > +See \fIhttp://vger.kernel.org/bpfconf2019_talks/bpf-core.pdf\fR. Can you please point to [0] instead? That linked presentation is already a bit out of date and will bitrot much faster. Blog post has at least a chance at being updated with relevant important stuff. Plus it has links both to the bpfconf2019 presentation, as well as some other resources (including your presentation). [0] https://nakryiko.com/posts/bpf-portability-and-co-re/ > + > .TP > .B \-\-btf_encode_force > Ignore those symbols found invalid when encoding BTF. > [acme@five pahole]$