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=-16.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=unavailable 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 EE381C4708F for ; Tue, 1 Jun 2021 19:07:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D77626135D for ; Tue, 1 Jun 2021 19:07:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234678AbhFATJQ (ORCPT ); Tue, 1 Jun 2021 15:09:16 -0400 Received: from mail.kernel.org ([198.145.29.99]:47252 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233397AbhFATJP (ORCPT ); Tue, 1 Jun 2021 15:09:15 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id DB266611CA; Tue, 1 Jun 2021 19:07:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1622574454; bh=L2UfCuZdh3bYpjGqac8bml/rp6oPqGoD9WBWvOT8i04=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=aTjaVSCwJy4p6ptS6WkSklhEawUZRo+zByYngAsGiozlZRrVUmSfiQh82Ve+sqXBT Tr+xAezHyQBGBocBuXCuGjEwep2NUK6wd+csd0b5+QUTPl/jEpQKKvv/LsbbPcgHIn 5L7wCXYQqykV2rM0PT3sTG/Y6tSde46agF3YWjcuDTNVsINwlhn9DDxpFxtWtuMI0+ xs3Z5oHGYsNkEg9xI3n1Lr8eG+dcjdKEsgLqwEppYCKCM71Fn99MbsmV2bav/MAXEy A+YpZXFDQg8eBRqG0J7mQjgZl4kxqmZC5BbUoKnXjAwx2qzL6y4btCk192v90I0o+t YBaqnqSOMzI/A== Received: by quaco.ghostprotocols.net (Postfix, from userid 1000) id AB9214011C; Tue, 1 Jun 2021 16:07:30 -0300 (-03) Date: Tue, 1 Jun 2021 16:07:30 -0300 From: Arnaldo Carvalho de Melo To: Jiri Olsa Cc: Arnaldo Carvalho de Melo , Andrii Nakryiko , Andrii Nakryiko , Jiri Olsa , Michal =?iso-8859-1?Q?Such=E1nek?= , dwarves@vger.kernel.org, bpf , Kernel Team , Michael Petlan Subject: Re: [RFT] Testing 1.22 Message-ID: References: <4615C288-2CFD-483E-AB98-B14A33631E2F@gmail.com> <4901AF88-0354-428B-9305-2EDC6F75C073@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Url: http://acmel.wordpress.com Precedence: bulk List-ID: X-Mailing-List: dwarves@vger.kernel.org Em Sun, May 30, 2021 at 11:45:15PM +0200, Jiri Olsa escreveu: > On Fri, May 28, 2021 at 04:45:31PM -0300, Arnaldo Carvalho de Melo wrote: > > Em Thu, May 27, 2021 at 01:41:13PM -0700, Andrii Nakryiko escreveu: > > > On Thu, May 27, 2021 at 12:57 PM Arnaldo wrote: > > > > On May 27, 2021 4:14:17 PM GMT-03:00, Andrii Nakryiko wrote: > > > > >If we make 1.22 mandatory there will be no good reason to make 1.23 > > > > >mandatory again. So I will have absolutely no inclination to work on > > > > >this, for example. So we are just wasting a chance to clean up the > > > > >Kbuild story w.r.t. pahole. And we are talking about just a few days > > > > >at most, while we do have a reasonable work around on the kernel side. > > > > > > So there were patches for stop using objcopy, which we thought could > > > > uncover some can of worms, were there patches for the detached BTF > > > > file? > > > > > No, there weren't, if I remember correctly. What's the concern, > > > though? That detached BTF file isn't even an ELF, so it's > > > btf__get_raw_data() and write it to the file. Done. > > > > See patch below, lightly tested, now working on making pahole accept raw > > BTF files out of /sys/kernel/btf/ > > > > Please test, and if works as expected, try to bolt this into the kbuild > > process, as intended. > > > > - Arnaldo > > > > commit b579a18a1ea0ee84b90b5302f597dda2edf2f61b > > Author: Arnaldo Carvalho de Melo > > Date: Fri May 28 16:41:30 2021 -0300 > > > > pahole: Allow encoding BTF into a detached file > > > > Previously the newly encoded BTF info was stored into a ELF section in > > the file where the DWARF info was obtained, but it is useful to just > > dump it into a separate file, do it. > > > > Requested-by: Andrii Nakryiko > > Signed-off-by: Arnaldo Carvalho de Melo > > > > diff --git a/btf_encoder.c b/btf_encoder.c > > index 033c927b537dad1e..bc3ac72968cea826 100644 > > --- a/btf_encoder.c > > +++ b/btf_encoder.c > > @@ -21,6 +21,14 @@ > > #include /* for qsort() and bsearch() */ > > #include > > > > +#include > > +#include > > +#include > > + > > +#include > > + > > +#include > > + > > /* > > * This corresponds to the same macro defined in > > * include/linux/kallsyms.h > > @@ -267,14 +275,62 @@ static struct btf_elf *btfe; > > static uint32_t array_index_id; > > static bool has_index_type; > > > > -int btf_encoder__encode() > > +static int btf_encoder__dump(struct btf *btf, const char *filename) > > +{ > > + uint32_t raw_btf_size; > > + const void *raw_btf_data; > > + int fd, err; > > + > > + /* Empty file, nothing to do, so... done! */ > > + if (btf__get_nr_types(btf) == 0) > > + return 0; > > + > > + if (btf__dedup(btf, NULL, NULL)) { > > + fprintf(stderr, "%s: btf__dedup failed!\n", __func__); > > + return -1; > > + } > > + > > + raw_btf_data = btf__get_raw_data(btf, &raw_btf_size); > > + if (raw_btf_data == NULL) { > > + fprintf(stderr, "%s: btf__get_raw_data failed!\n", __func__); > > + return -1; > > + } > > + > > + fd = open(filename, O_WRONLY | O_CREAT); > > I think you need to specify file mode as 3rd param: Right you are! I've read this comment from you and, left it for later and then when I used btf__parse_split("vmlinux.btf", NULL) as Andrii suggested, I got a EPERM, erm? tried btf__parse-split("/sys/kernel/btf/vmlinux", NULL), it worked, humm, yeah, Jiri mentioned something about weird modes... Fixed it using 'chmod 644' and it worked. Now fixing it by adding the 3rd param, thanks! - Arnaldo > $ ./pahole -j krava vmlinux > $ ~/linux/tools/bpf/bpftool/bpftool btf dump file ./krava > Error: failed to load BTF from ./krava: Permission denied > $ ll krava > --w-r-Sr-T. 1 jolsa jolsa 4525734 May 30 23:38 krava > > jirka > -- - Arnaldo