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=-5.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 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 ED7D5C4363D for ; Wed, 23 Sep 2020 02:06:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B4D29238A1 for ; Wed, 23 Sep 2020 02:06:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726990AbgIWCGC (ORCPT ); Tue, 22 Sep 2020 22:06:02 -0400 Received: from mga07.intel.com ([134.134.136.100]:49987 "EHLO mga07.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726743AbgIWCGC (ORCPT ); Tue, 22 Sep 2020 22:06:02 -0400 IronPort-SDR: WNdGJq55YN8QU6aywQvoqRZ5rV621POHolcXwdXIOOHeYtZe4917hm1A4cQh4ji7k3Oh6xEN9X TlP0zgfWHpeA== X-IronPort-AV: E=McAfee;i="6000,8403,9752"; a="224911042" X-IronPort-AV: E=Sophos;i="5.77,292,1596524400"; d="scan'208";a="224911042" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga005.jf.intel.com ([10.7.209.41]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 22 Sep 2020 19:06:01 -0700 IronPort-SDR: AxWHI+bf0w/s56LN2ioeMS3GOXSoy9kr4iqCHYaYYsu9dRKswVDiNEY9m9E9sukd3LfLHoTMYT xze0h+g/4uYA== X-IronPort-AV: E=Sophos;i="5.77,292,1596524400"; d="scan'208";a="486227068" Received: from yjin15-mobl1.ccr.corp.intel.com (HELO [10.238.5.239]) ([10.238.5.239]) by orsmga005-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 22 Sep 2020 19:05:59 -0700 Subject: Re: [PATCH] perf stat: Skip duration_time in setup_system_wide To: Arnaldo Carvalho de Melo Cc: jolsa@kernel.org, peterz@infradead.org, mingo@redhat.com, alexander.shishkin@linux.intel.com, Linux-kernel@vger.kernel.org, ak@linux.intel.com, kan.liang@intel.com, yao.jin@intel.com References: <20200922015004.30114-1-yao.jin@linux.intel.com> <20200922175630.GB2248446@kernel.org> <20200922180218.GC2248446@kernel.org> From: "Jin, Yao" Message-ID: <8b4e9938-2d15-8320-85e9-e14ddd51c743@linux.intel.com> Date: Wed, 23 Sep 2020 10:05:56 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.12.0 MIME-Version: 1.0 In-Reply-To: <20200922180218.GC2248446@kernel.org> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Arnaldo, On 9/23/2020 2:02 AM, Arnaldo Carvalho de Melo wrote: > Em Tue, Sep 22, 2020 at 02:56:30PM -0300, Arnaldo Carvalho de Melo escreveu: >> Em Tue, Sep 22, 2020 at 09:50:04AM +0800, Jin Yao escreveu: >>> Some metrics (such as DRAM_BW_Use) consists of uncore events and >>> duration_time. For uncore events, counter->core.system_wide is >>> true. But for duration_time, counter->core.system_wide is false >>> so target.system_wide is set to false. >>> >>> Then 'enable_on_exec' is set in perf_event_attr of uncore event. >>> Kernel will return error when trying to open the uncore event. >>> >>> This patch skips the duration_time in setup_system_wide then >>> target.system_wide will be set to true for the evlist of uncore >>> events + duration_time. >>> >>> Before (tested on skylake desktop): >>> >>> # perf stat -M DRAM_BW_Use -- sleep 1 >>> Error: >>> The sys_perf_event_open() syscall returned with 22 (Invalid argument) for event (arb/event=0x84,umask=0x1/). >>> /bin/dmesg | grep -i perf may provide additional information. >>> >>> After: >>> >>> # perf stat -M DRAM_BW_Use -- sleep 1 >>> >>> Performance counter stats for 'system wide': >>> >>> 169 arb/event=0x84,umask=0x1/ # 0.00 DRAM_BW_Use >>> 40,427 arb/event=0x81,umask=0x1/ >>> 1,000,902,197 ns duration_time >>> >>> 1.000902197 seconds time elapsed >>> >>> Fixes: 648b5af3f3ae ("libperf: Move 'system_wide' from 'struct evsel' to 'struct perf_evsel'") >> >> Humm, what makes you think that this cset was the one introducing this >> problem? It just moves evsel->system_wide to evsel->core.system_wide. > > Apart from that I reproduced the problem and after applying your patch > it seems cured: > > [acme@quaco perf]$ grep 'model name' -m1 /proc/cpuinfo > model name : Intel(R) Core(TM) i7-8650U CPU @ 1.90GHz > > Before (with -v to see details): > > [root@quaco ~]# perf stat -v -M DRAM_BW_Use -- sleep 1 > Using CPUID GenuineIntel-6-8E-A > metric expr 64 * ( arb@event\=0x81\,umask\=0x1@ + arb@event\=0x84\,umask\=0x1@ ) / 1000000 / duration_time / 1000 for DRAM_BW_Use > found event duration_time > found event arb/event=0x84,umask=0x1/ > found event arb/event=0x81,umask=0x1/ > adding {arb/event=0x84,umask=0x1/,arb/event=0x81,umask=0x1/}:W,duration_time > Control descriptor is not initialized > Warning: > arb/event=0x84,umask=0x1/ event is not supported by the kernel. > Error: > The sys_perf_event_open() syscall returned with 22 (Invalid argument) for event (arb/event=0x84,umask=0x1/). > /bin/dmesg | grep -i perf may provide additional information. > > [root@quaco ~]# > > After: > > [root@quaco ~]# perf stat -M DRAM_BW_Use -- sleep 1 > > Performance counter stats for 'system wide': > > 2,806 arb/event=0x84,umask=0x1/ # 0.63 DRAM_BW_Use > 10,001,820 arb/event=0x81,umask=0x1/ > 1,016,875,686 ns duration_time > > 1.016875686 seconds time elapsed > > [root@quaco ~]# > > So I'm removing that fixes and adding this one, that I think is where > "duration_time" was being considered... > > Fixes: e3ba76deef23064f ("perf tools: Force uncore events to system wide monitoring") > Yes, this fixes is much better, thanks. > Also, wouldn't it be better to have the duration_time event with its > evsel->core.system_wide set to true? > That looks to be another solution, should be OK too I think. :) But anyway we need a test. Thanks Jin Yao > - Arnaldo >