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=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=ham 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 04294C433E0 for ; Tue, 7 Jul 2020 13:07:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D716120771 for ; Tue, 7 Jul 2020 13:07:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728165AbgGGNH4 (ORCPT ); Tue, 7 Jul 2020 09:07:56 -0400 Received: from mga01.intel.com ([192.55.52.88]:26262 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725944AbgGGNHy (ORCPT ); Tue, 7 Jul 2020 09:07:54 -0400 IronPort-SDR: lmQk0uXFw2UQkF39E19XjIQs01MG1OtrWe7hiKKOuZJpeVTGlbaccItHxMH6RRcJpoIs91Q0Rz HlF/TM3SWrvQ== X-IronPort-AV: E=McAfee;i="6000,8403,9674"; a="165662873" X-IronPort-AV: E=Sophos;i="5.75,323,1589266800"; d="scan'208";a="165662873" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga004.jf.intel.com ([10.7.209.38]) by fmsmga101.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 07 Jul 2020 06:07:46 -0700 IronPort-SDR: ww/4rtd2LrlsJUXXXeFFGmglA/U8HTWP9/QTxfeZ2fv+zEcThHcwoabRnCfYMsqMrHfgLZkFJW UwV8Z69MyEIw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.75,323,1589266800"; d="scan'208";a="427467528" Received: from linux.intel.com ([10.54.29.200]) by orsmga004.jf.intel.com with ESMTP; 07 Jul 2020 06:07:46 -0700 Received: from [10.249.228.33] (abudanko-mobl.ccr.corp.intel.com [10.249.228.33]) by linux.intel.com (Postfix) with ESMTP id 1FC9C5807C8; Tue, 7 Jul 2020 06:07:43 -0700 (PDT) Subject: Re: [PATCH v9 11/15] perf stat: implement control commands handling To: Jiri Olsa Cc: Arnaldo Carvalho de Melo , Namhyung Kim , Alexander Shishkin , Peter Zijlstra , Ingo Molnar , Andi Kleen , linux-kernel References: <21669f5a-6220-df0a-09f1-b73b32487f23@linux.intel.com> <20200706123436.GD3401866@krava> <6cf91811-ea6a-3c7c-8bbf-7f96bfa1fc82@linux.intel.com> <20200706193418.GB3424581@krava> From: Alexey Budankov Organization: Intel Corp. Message-ID: Date: Tue, 7 Jul 2020 16:07:42 +0300 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <20200706193418.GB3424581@krava> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 06.07.2020 22:34, Jiri Olsa wrote: > On Mon, Jul 06, 2020 at 05:47:54PM +0300, Alexey Budankov wrote: >> >> On 06.07.2020 15:34, Jiri Olsa wrote: >>> On Fri, Jul 03, 2020 at 10:47:22AM +0300, Alexey Budankov wrote: >>>> >>>> Implement handling of 'enable' and 'disable' control commands >>>> coming from control file descriptor. process_evlist() function >>>> checks for events on control fds and makes required operations. >>>> If poll event splits initiated timeout interval then the reminder >>>> is calculated and still waited in the following poll() syscall. >>>> >>>> Signed-off-by: Alexey Budankov >>>> --- >>>> tools/perf/builtin-stat.c | 75 ++++++++++++++++++++++++++++----------- >>>> 1 file changed, 55 insertions(+), 20 deletions(-) >>>> >>>> diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c >>>> index 9e4288ecf2b8..5021f7286422 100644 >>>> --- a/tools/perf/builtin-stat.c >>>> +++ b/tools/perf/builtin-stat.c >>>> @@ -485,6 +485,31 @@ static bool handle_interval(unsigned int interval, int *times) >>>> return false; >>>> } >>>> >>>> +static bool process_evlist(struct evlist *evlist, unsigned int interval, int *times) >>>> +{ >>>> + bool stop = false; >>>> + enum evlist_ctl_cmd cmd = EVLIST_CTL_CMD_UNSUPPORTED; >>>> + >>>> + if (evlist__ctlfd_process(evlist, &cmd) > 0) { >>>> + switch (cmd) { >>>> + case EVLIST_CTL_CMD_ENABLE: >>>> + pr_info(EVLIST_ENABLED_MSG); >>>> + stop = handle_interval(interval, times); >>>> + break; >>>> + case EVLIST_CTL_CMD_DISABLE: >>>> + stop = handle_interval(interval, times); >>> >>> I still don't understand why you call handle_interval in here >>> >>> I don't see it being necessary.. you enable events and handle_interval, >>> wil be called in the next iteration of dispatch_events, why complicate >>> this function with that? >> >> Printing event counts at the moment of command processing lets scripts >> built on top of stat output to provide more plain and accurate metrics. >> Otherwise it may get spikes in the beginning of the next time interval >> because not all counts lay inside [Events enabled, Events disable] >> If -I interval is large tail event count can be also large. Compare the >> output below with the output in the cover letter. Either way is possible >> but the latter one likely complicates the scripts I mentioned above. >> >> perf=tools/perf/perf >> ${perf} stat -D -1 -e cpu-cycles -a -I 1000 \ >> --control fd:${ctl_fd},${ctl_fd_ack} \ >> -- sleep 40 & >> >> Events disabled >> # time counts unit events >> 1.001100723 cpu-cycles >> 2.003146566 cpu-cycles >> 3.005073317 cpu-cycles >> 4.006337062 cpu-cycles >> Events enabled >> enable acked(ack) >> 5.011182000 54,128,692 cpu-cycles <=== >> 6.012300167 3,648,804,827 cpu-cycles >> 7.013631689 590,438,536 cpu-cycles >> 8.015558583 406,935,663 cpu-cycles >> 9.017455505 407,806,862 cpu-cycles >> 10.019300780 399,351,824 cpu-cycles >> 11.021180025 404,584,417 cpu-cycles >> 12.023033661 537,787,981 cpu-cycles >> 13.024422354 699,395,364 cpu-cycles >> 14.026325749 397,871,324 cpu-cycles >> disable acked() >> Events disabled >> 15.027857981 396,956,159 cpu-cycles <=== >> 16.029279264 cpu-cycles >> 17.031131311 cpu-cycles >> 18.033010580 cpu-cycles >> 19.034918883 cpu-cycles >> enable acked(ack) >> Events enabled >> 20.036758793 183,544,975 cpu-cycles <=== >> 21.038163289 419,054,544 cpu-cycles >> 22.040108245 413,993,309 cpu-cycles >> 23.042042365 403,584,493 cpu-cycles >> 24.043985381 416,512,094 cpu-cycles >> 25.045925682 401,513,429 cpu-cycles >> # time counts unit events >> 26.047822238 461,205,096 cpu-cycles >> 27.049784263 414,319,162 cpu-cycles >> 28.051745360 403,706,915 cpu-cycles >> 29.053674600 416,502,883 cpu-cycles >> disable acked() >> Events disabled >> 30.054750685 414,184,409 cpu-cycles <=== > > ok, but we could still take handle_interval out of process_evlist > and the interval process will be more clear for me (with some > additional comments in the code) ... perhaps something like below? > > thanks, > jirka > > > --- > diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c > index 5021f7286422..af83bf6b2db0 100644 > --- a/tools/perf/builtin-stat.c > +++ b/tools/perf/builtin-stat.c > @@ -485,19 +485,18 @@ static bool handle_interval(unsigned int interval, int *times) > return false; > } > > -static bool process_evlist(struct evlist *evlist, unsigned int interval, int *times) > +static bool process_evlist(struct evlist *evlist) > { > - bool stop = false; > enum evlist_ctl_cmd cmd = EVLIST_CTL_CMD_UNSUPPORTED; > + bool enabled = false; > > if (evlist__ctlfd_process(evlist, &cmd) > 0) { > switch (cmd) { > case EVLIST_CTL_CMD_ENABLE: > pr_info(EVLIST_ENABLED_MSG); > - stop = handle_interval(interval, times); > + enabled = true; > break; > case EVLIST_CTL_CMD_DISABLE: > - stop = handle_interval(interval, times); > pr_info(EVLIST_DISABLED_MSG); > break; > case EVLIST_CTL_CMD_ACK: > @@ -507,7 +506,7 @@ static bool process_evlist(struct evlist *evlist, unsigned int interval, int *ti > } > } > > - return stop; > + return enabled; > } > > static void enable_counters(void) > @@ -618,7 +617,8 @@ static int dispatch_events(bool forks, int timeout, int interval, int *times) > stop = handle_interval(interval, times); > time_to_sleep = sleep_time; > } else { /* fd revent */ > - stop = process_evlist(evsel_list, interval, times); > + if (process_evlist(evsel_list)) > + stop = handle_interval(interval, times); It will call only on enable command and lead to artificial spikes in the beginning of interval. May be just take handle_interval() out of process_evlist() and have it similar to record case? Alexey