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 0EDF4C4332F for ; Thu, 9 Nov 2023 16:46:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344200AbjKIQq1 (ORCPT ); Thu, 9 Nov 2023 11:46:27 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53916 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1344364AbjKIQqA (ORCPT ); Thu, 9 Nov 2023 11:46:00 -0500 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A6D3A35BF for ; Thu, 9 Nov 2023 08:45:52 -0800 (PST) Received: by smtp.kernel.org (Postfix) with ESMTPSA id E6098C433C7; Thu, 9 Nov 2023 16:45:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1699548352; bh=/TMgD2FsXKux1Lc8LfTtqxrYiMDimiXal92g6Us2e7k=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=O5od+4b0BoLWRpWe5K2bofV7PU0++ewP+Lk5sHrYGW/3sHGGoh08eqkXxd/zr/Adp sXPHoZL8ip/OiVDawjtRDzaUxbqwCBwEtsT180Z575z1YvvtutPX7/0oo7vSq3UDjc AF4F1U6/fJ9VETvTePWvapY3BDXvK+vMxmCwc+kWKUPd0GhY0MSI+5k1fr915CGOas 1n5zb6O37n7idWOFcT/8wEPyd0RKU9A6NBAuYVkYB65xzk4T3cRi3dp5o1fYSHdNTh Oj3/oK+wQWBbN16dkpjPiCtBe+yoF+n/WssdD6Pd25MXEnhni7lxWpdthaoI2gsdll /cR5WN194fxcg== Received: by quaco.ghostprotocols.net (Postfix, from userid 1000) id 67CE840094; Thu, 9 Nov 2023 13:45:49 -0300 (-03) Date: Thu, 9 Nov 2023 13:45:49 -0300 From: Arnaldo Carvalho de Melo To: "Liang, Kan" Cc: peterz@infradead.org, mingo@redhat.com, linux-kernel@vger.kernel.org, mark.rutland@arm.com, alexander.shishkin@linux.intel.com, jolsa@kernel.org, namhyung@kernel.org, irogers@google.com, adrian.hunter@intel.com, ak@linux.intel.com, eranian@google.com, alexey.v.bayduraev@linux.intel.com, tinghao.zhang@intel.com Subject: Re: [PATCH V5 2/8] perf/x86: Add PERF_X86_EVENT_NEEDS_BRANCH_STACK flag Message-ID: References: <20231025201626.3000228-1-kan.liang@linux.intel.com> <20231025201626.3000228-2-kan.liang@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable In-Reply-To: X-Url: http://acmel.wordpress.com Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Em Thu, Nov 09, 2023 at 11:14:31AM -0500, Liang, Kan escreveu: >=20 >=20 > On 2023-11-08 4:31 p.m., Arnaldo Carvalho de Melo wrote: > > Em Tue, Nov 07, 2023 at 12:11:50PM -0300, Arnaldo Carvalho de Melo escr= eveu: > >> Em Mon, Nov 06, 2023 at 04:19:13PM -0500, Liang, Kan escreveu: > >>> On 2023-11-06 4:12 p.m., Arnaldo Carvalho de Melo wrote: > >>>> Em Wed, Oct 25, 2023 at 01:16:20PM -0700, kan.liang@linux.intel.com = escreveu: > >>> Ian has already reviewed the tool parts. > >=20 > >>> But I still owe a test case for the feature. I will post a patch late= r. > >>> https://lore.kernel.org/lkml/acbb895a-475e-4679-98fc-6b90c05a00af@lin= ux.intel.com/ > >=20 > >> I saw Ian's suggestion, and agree with it, we need to pair new features > >> with regression tests in 'perf test', thanks for working on it! > >=20 > > Kan, > >=20 > > I still have to bisect, but can you check if this works for you? >=20 > The branch counters feature requires all the events to belong to a > group. There is no problem for the normal perf usage which usually > initializes an evlist even for a single evsel. > But perf test is special, which may not initialize an evlist. The Sample > parsing test case is one of the examples. It crashes with the > !evsel->evlist. >=20 > The below change should fix it. I will post a complete patch shortly. Thanks for the quick response, if all that is needed are the checks below, I'll fold it into your original patch: 2ae01908298426e4 perf tools: Add branch counter knob So that we don't regress, ok? I'll add a note and the Link tag points to this discussion in case people want to do historical digs in the future :-) - Arnaldo =20 > diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c > index 58a9b8c82790..7a6a2d1f96db 100644 > --- a/tools/perf/util/evsel.c > +++ b/tools/perf/util/evsel.c > @@ -2355,6 +2355,10 @@ static inline bool > evsel__has_branch_counters(const struct evsel *evsel) > { > struct evsel *cur, *leader =3D evsel__leader(evsel); >=20 > + /* The branch counters feature only supports group */ > + if (!leader || !evsel->evlist) > + return false; > + > evlist__for_each_entry(evsel->evlist, cur) { > if ((leader =3D=3D evsel__leader(cur)) && > (cur->core.attr.branch_sample_type & > PERF_SAMPLE_BRANCH_COUNTERS)) >=20 > Thanks, > Kan >=20 > >=20 > >=20 > > (gdb) run test -F -v 27 > > Starting program: /root/bin/perf test -F -v 27 > >=20 > > 27: Sample parsing : > > --- start --- > >=20 > > Program received signal SIGSEGV, Segmentation fault. > > 0x00000000004e4aa6 in evsel.parse_sample () > > Missing separate debuginfos, use: dnf debuginfo-install bzip2-libs-1.0.= 8-13.fc38.x86_64 cyrus-sasl-lib-2.1.28-9.fc38.x86_64 elfutils-debuginfod-cl= ient-0.189-3.fc38.x86_64 elfutils-libelf-0.189-3.fc38.x86_64 elfutils-libs-= 0.189-3.fc38.x86_64 glib2-2.76.5-2.fc38.x86_64 glibc-2.37-13.fc38.x86_64 ke= yutils-libs-1.6.1-6.fc38.x86_64 krb5-libs-1.21-3.fc38.x86_64 libbabeltrace-= 1.5.11-2.fc38.x86_64 libbrotli-1.0.9-11.fc38.x86_64 libcap-2.48-6.fc38.x86_= 64 libcom_err-1.46.5-4.fc38.x86_64 libcurl-8.0.1-5.fc38.x86_64 libevent-2.1= =2E12-8.fc38.x86_64 libgcc-13.2.1-4.fc38.x86_64 libidn2-2.3.4-2.fc38.x86_64= libnghttp2-1.52.0-2.fc38.x86_64 libpfm-4.11.0-11.fc38.x86_64 libpsl-0.21.2= -2.fc38.x86_64 libselinux-3.5-1.fc38.x86_64 libssh-0.10.5-1.fc38.x86_64 lib= stdc++-13.2.1-4.fc38.x86_64 libtraceevent-1.7.2-1.fc38.x86_64 libunistring1= =2E0-1.0-1.fc38.x86_64 libunwind-1.6.2-7.fc38.x86_64 libuuid-2.38.1-4.fc38.= x86_64 libxcrypt-4.4.36-1.fc38.x86_64 libzstd-1.5.5-1.fc38.x86_64 opencsd-1= =2E3.3-1.fc38.x86_64 openldap-2.6.6-1.fc38.x86_64 openssl-libs-3.0.9-2.fc38= =2Ex86_64 perl-libs-5.36.1-497.fc38.x86_64 popt-1.19-2.fc38.x86_64 python3-= libs-3.11.6-1.fc38.x86_64 slang-2.3.3-3.fc38.x86_64 zlib-1.2.13-3.fc38.x86_= 64 > > (gdb) bt > > #0 0x00000000004e4aa6 in evsel.parse_sample () > > #1 0x00000000004b28dc in do_test () > > #2 0x00000000004b2acd in test.sample_parsing () > > #3 0x0000000000495348 in test_and_print.isra () > > #4 0x0000000000495f5d in cmd_test () > > #5 0x00000000004c2a29 in run_builtin () > > #6 0x000000000041053f in main () > > (gdb) > >=20 --=20 - Arnaldo