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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8D28DC6FA89 for ; Thu, 8 Sep 2022 18:31:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229898AbiIHSbb (ORCPT ); Thu, 8 Sep 2022 14:31:31 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51058 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229583AbiIHSb1 (ORCPT ); Thu, 8 Sep 2022 14:31:27 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E77FA74BAE; Thu, 8 Sep 2022 11:31:26 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 701F161DE1; Thu, 8 Sep 2022 18:31:26 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A9EFBC433D6; Thu, 8 Sep 2022 18:31:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1662661885; bh=pwiS6dxc4KyhjhtcsKVTP/Sq/be3I4Y28Qt1YVLE2zA=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=ZZKPXlPt65enO3t/+8wobhXq8Rebtsjiw0UxB9PA+OwPCW9zOPne9ygTXi+6IBlFx nU6CQEeZW3c7lyl2UQ7YJB2e7F13d6HRrhH3V9AxxLUVy1yWKWTQyBFKo+8/Sve31x 9DWPJqNX5wAmPcnTdxfuwTwtb/bQlGZ8F8bU2q/mNE5ChQGuVYwo1nRCvoIsmw7YnX F5my9C8bkkgiKhmAY7K8K2siA0FJJUnIo9lft8XS6qtTNYCxk+Bx+xceREcoPS1TXm V6bnF4iuWW6ALw5FRqiTcgNbbL1+xMrcihvsna+jcLUpjn2Ir9w/q+/aLtjDLPur3a 3etG12xvDLP2g== Received: by quaco.ghostprotocols.net (Postfix, from userid 1000) id 0D6BB404A1; Thu, 8 Sep 2022 15:31:23 -0300 (-03) Date: Thu, 8 Sep 2022 15:31:23 -0300 From: Arnaldo Carvalho de Melo To: Namhyung Kim Cc: Jiri Olsa , Ingo Molnar , Peter Zijlstra , LKML , Ian Rogers , linux-perf-users@vger.kernel.org, bpf@vger.kernel.org, Marco Elver , Song Liu Subject: Re: [PATCH v2] perf test: Skip sigtrap test on old kernels Message-ID: References: <20220907050407.2711513-1-namhyung@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220907050407.2711513-1-namhyung@kernel.org> X-Url: http://acmel.wordpress.com Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Em Tue, Sep 06, 2022 at 10:04:07PM -0700, Namhyung Kim escreveu: > If it runs on an old kernel, perf_event_open would fail because of the > new fields sigtrap and sig_data. Just skipping the test could miss an > actual bug in the kernel. > > Let's check BTF if it has the perf_event_attr.sigtrap field. > > Cc: Marco Elver > Cc: Song Liu > Signed-off-by: Namhyung Kim > --- > tools/perf/tests/sigtrap.c | 46 +++++++++++++++++++++++++++++++++++++- > 1 file changed, 45 insertions(+), 1 deletion(-) > > diff --git a/tools/perf/tests/sigtrap.c b/tools/perf/tests/sigtrap.c > index e32ece90e164..32f08ce0f2b0 100644 > --- a/tools/perf/tests/sigtrap.c > +++ b/tools/perf/tests/sigtrap.c > @@ -16,6 +16,8 @@ > #include > #include > > +#include > + > #include "cloexec.h" > #include "debug.h" > #include "event.h" > @@ -54,6 +56,42 @@ static struct perf_event_attr make_event_attr(void) > return attr; > } > > +static bool attr_has_sigtrap(void) > +{ > + bool ret = false; > + > +#ifdef HAVE_BPF_SKEL > + > + struct btf *btf; > + const struct btf_type *t; > + const struct btf_member *m; > + const char *name; > + int i, id; > + > + /* just assume it doesn't have the field */ > + btf = btf__load_vmlinux_btf(); Cool, at some point we'll probably move this to some other global place, doing the lazy loading and keeping it in place as probably we'll use it more often :-) Waiting for v2. Thanks for working on this. - Arnaldo > + if (btf == NULL) > + return false; > + > + id = btf__find_by_name_kind(btf, "perf_event_attr", BTF_KIND_STRUCT); > + if (id < 0) > + goto out; > + > + t = btf__type_by_id(btf, id); > + for (i = 0, m = btf_members(t); i < btf_vlen(t); i++, m++) { > + name = btf__name_by_offset(btf, m->name_off); > + if (!strcmp(name, "sigtrap")) { > + ret = true; > + break; > + } > + } > +out: > + btf__free(btf); > +#endif > + > + return ret; > +} > + > static void > sigtrap_handler(int signum __maybe_unused, siginfo_t *info, void *ucontext __maybe_unused) > { > @@ -139,7 +177,13 @@ static int test__sigtrap(struct test_suite *test __maybe_unused, int subtest __m > > fd = sys_perf_event_open(&attr, 0, -1, -1, perf_event_open_cloexec_flag()); > if (fd < 0) { > - pr_debug("FAILED sys_perf_event_open(): %s\n", str_error_r(errno, sbuf, sizeof(sbuf))); > + if (attr_has_sigtrap()) { > + pr_debug("FAILED sys_perf_event_open(): %s\n", > + str_error_r(errno, sbuf, sizeof(sbuf))); > + } else { > + pr_debug("perf_event_attr doesn't have sigtrap\n"); > + ret = TEST_SKIP; > + } > goto out_restore_sigaction; > } > > -- > 2.37.2.789.g6183377224-goog -- - Arnaldo