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 AD89BC433EF for ; Fri, 25 Mar 2022 21:46:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233557AbiCYVsK (ORCPT ); Fri, 25 Mar 2022 17:48:10 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46610 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233526AbiCYVru (ORCPT ); Fri, 25 Mar 2022 17:47:50 -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 AE78E26D128 for ; Fri, 25 Mar 2022 14:46:13 -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 5618E6104B for ; Fri, 25 Mar 2022 21:46:13 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7CF7EC2BBE4; Fri, 25 Mar 2022 21:46:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1648244772; bh=h1ODuaZR6lqIhjCO5G+BxG/QKwpoe+nyYQtSLeprXKg=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=CeAe1c7j0tvw5ZNCuZqo237aQsUfB6h7HJHcTbXSDMiU4a7aT7W0LT4WYby3MRfyT 1NXVaLO0q2I4Vg6Mi5gBj2OXm6LLGW5w/Qx3XPIZbKRw6aEMS584UWrTom6pd9zp6G qVSaVHSvLy9TN5fAiMBYUB5oriXqongqICE9gKd9pqJDxskHTjk1em2yl3qhApeeT5 CEvLCB7wv8mSxwzZWX05N4orwV1J7jTidLBlK0woQcPTmiv/spLGie8y01ZRbmSsa3 QWODpDoImyHP2BNH3To9O67DW1aruiNDxbAVZc6OjBefuTP6mS5Db0a+0j9GjAJeje m6S54nidF31rw== Received: by quaco.ghostprotocols.net (Postfix, from userid 1000) id 80B2C40407; Fri, 25 Mar 2022 18:46:08 -0300 (-03) Date: Fri, 25 Mar 2022 18:46:08 -0300 From: Arnaldo Carvalho de Melo To: Stephane Eranian Cc: linux-kernel@vger.kernel.org, peterz@infradead.org, kim.phillips@amd.com, acme@redhat.com, jolsa@redhat.com, songliubraving@fb.com, rafael@kernel.org, ravi.bangoria@amd.com, sandipan.das@amd.com Subject: Re: [PATCH v7 11/13] perf tools: Improve IBS error handling Message-ID: References: <20220322221517.2510440-1-eranian@google.com> <20220322221517.2510440-12-eranian@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220322221517.2510440-12-eranian@google.com> X-Url: http://acmel.wordpress.com Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Em Tue, Mar 22, 2022 at 03:15:15PM -0700, Stephane Eranian escreveu: > From: Kim Phillips > > improve the error message returned on failed perf_event_open() on AMD when > using IBS. > > Output of executing 'perf record -e ibs_op// true' BEFORE this patch: > > The sys_perf_event_open() syscall returned with 22 (Invalid argument)for event (ibs_op//u). > /bin/dmesg | grep -i perf may provide additional information. > > Output after: > > AMD IBS cannot exclude kernel events. Try running at a higher privilege level. So the error message don't match up the BEFORE part, that didn't have a "u" at the end, and with this patch in: $ git log --oneline -1 ca585f91ce13df4c (HEAD -> perf/core) perf evsel: Improve AMD IBS (Instruction-Based Sampling) error handling messages # perf -v perf version 5.17.gca585f91ce13 # On a: # grep -m1 "model name" /proc/cpuinfo model name : AMD Ryzen 9 5950X 16-Core Processor # If I try: # perf record -e ibs_op//u true Error: Invalid event (ibs_op//u) in per-thread mode, enable system wide with '-a'. # So now if I try: # perf record -a -e ibs_op//u true Error: AMD IBS can't exclude kernel events. Try running at a higher privilege level. # So the problem is with the patch description, I'm fixing it. > Output of executing 'sudo perf record -e ibs_op// true' BEFORE this patch: > > Error: > The sys_perf_event_open() syscall returned with 22 (Invalid argument) for event (ibs_op//). > /bin/dmesg | grep -i perf may provide additional information. > > Output after: > > Error: > AMD IBS may only be available in system-wide/per-cpu mode. Try using -a, or -C and workload affinity But this one is never reached: [root@five ~]# perf record -e ibs_op// true Error: Invalid event (ibs_op//) in per-thread mode, enable system wide with '-a' > + if (!evsel->core.system_wide) > + return scnprintf(msg, size, > + "AMD IBS may only be available in system-wide/per-cpu mode. Try using -a, or -C and workload affinity"); I'm applying this to make progress, the message now provides more clues. - Arnaldo > Signed-off-by: Kim Phillips > Cc: Arnaldo Carvalho de Melo > Cc: Alexander Shishkin > Cc: Boris Ostrovsky > Cc: Ian Rogers > Cc: Ingo Molnar > Cc: Jiri Olsa > Cc: Joao Martins > Cc: Konrad Rzeszutek Wilk > Cc: Mark Rutland > Cc: Michael Petlan > Cc: Namhyung Kim > Cc: Peter Zijlstra > Cc: Robert Richter > Cc: Stephane Eranian > --- > tools/perf/util/evsel.c | 25 +++++++++++++++++++++++++ > 1 file changed, 25 insertions(+) > > diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c > index 14b0e7ffa2c7..e8ff7a4bd490 100644 > --- a/tools/perf/util/evsel.c > +++ b/tools/perf/util/evsel.c > @@ -2847,9 +2847,23 @@ static bool find_process(const char *name) > return ret ? false : true; > } > > +static bool is_amd(const char *arch, const char *cpuid) > +{ > + return arch && !strcmp("x86", arch) && cpuid && strstarts(cpuid, "AuthenticAMD"); > +} > + > +static bool is_amd_ibs(struct evsel *evsel) > +{ > + return evsel->core.attr.precise_ip > + || (evsel->pmu_name && !strncmp(evsel->pmu_name, "ibs", 3)); > +} > + > int evsel__open_strerror(struct evsel *evsel, struct target *target, > int err, char *msg, size_t size) > { > + struct perf_env *env = evsel__env(evsel); > + const char *arch = perf_env__arch(env); > + const char *cpuid = perf_env__cpuid(env); > char sbuf[STRERR_BUFSIZE]; > int printed = 0, enforced = 0; > > @@ -2949,6 +2963,17 @@ int evsel__open_strerror(struct evsel *evsel, struct target *target, > return scnprintf(msg, size, > "Invalid event (%s) in per-thread mode, enable system wide with '-a'.", > evsel__name(evsel)); > + if (is_amd(arch, cpuid)) { > + if (is_amd_ibs(evsel)) { > + if (evsel->core.attr.exclude_kernel) > + return scnprintf(msg, size, > + "AMD IBS can't exclude kernel events. Try running at a higher privilege level."); > + if (!evsel->core.system_wide) > + return scnprintf(msg, size, > + "AMD IBS may only be available in system-wide/per-cpu mode. Try using -a, or -C and workload affinity"); > + } > + } > + > break; > case ENODATA: > return scnprintf(msg, size, "Cannot collect data source with the load latency event alone. " > -- > 2.35.1.894.gb6a874cedc-goog -- - Arnaldo