From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755203AbeDTNxr (ORCPT ); Fri, 20 Apr 2018 09:53:47 -0400 Received: from szxga07-in.huawei.com ([45.249.212.35]:60754 "EHLO huawei.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1754872AbeDTNxo (ORCPT ); Fri, 20 Apr 2018 09:53:44 -0400 Subject: Re: s390 perf events JSONs query To: Thomas-Mich Richter , , References: <68e84967-ca29-0b86-027a-76307e003a55@huawei.com> CC: Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Alexander Shishkin , Jiri Olsa , "Namhyung Kim" , Linuxarm , , Will Deacon From: John Garry Message-ID: Date: Fri, 20 Apr 2018 14:53:27 +0100 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.3.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset="utf-8"; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: [10.202.227.238] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 20/04/2018 14:25, Thomas-Mich Richter wrote: > On 04/20/2018 12:51 PM, John Garry wrote: >> Hi Hendrik, Thomas, >> >> I noticed that in 4.17-rc1 support was included for s390 perf pmu-events. I also notice that the JSONs contain many common (identical actually) events between different chips for this arch. >> >> Support was added for factoring out common arch events in https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/tools/perf/pmu-events?h=next-20180420&id=e9d32c1bf0cd7a98358ec4aa1625bf2b3459b9ac >> >> ARM64 chips use this feature. I am not familiar with the s390 arch, but do you think you could also use this feature? >> >> Thanks, >> John >> > > I have just played with this feature. I was caught off by this error message: > > [root@s35lp76 pmu-events]# ./jevents s390 arch /tmp/xxx 100000 > d 0 4096 s390 arch/s390 > d 1 4096 cf_z14 arch/s390/cf_z14 > f 2 1338 basic.json arch/s390/cf_z14/basic.json > .... > jevents: Ignoring file arch/s390/archevent.json <---- confusing error message Let me check if this can be silenced. > > jevents: Processing mapfile arch/s390/mapfile.csv > [root@s35lp76 pmu-events]# > > I started debugging, until I realized this file is still processed..... > (Just a side remark). > > Anyway the features is nice, but it does not save anything in the resulting > pmu-events.c file, correct? The events defined in the common archevent.json > files are just copied into the structures of a specific machine. > Yes, the resulting derived pmu-events.c should be the same. In fact, if there was naming inconsistencies in JSONs previously, they should now be gone. > The feature saves time and space when you create the machine specific json > files because it allows you to refer to a common event by name. Cool! > > On s390 we do not create the json files manually, but have some scripts to > create them based on s390 type/model hardware specific input files. Right, I would say that this is mostly useful when the JSONs are created manually, which was the case in the ARM world, but not x86. I didn't know about s390. > > @Hendirk, > we could rework our internal tool chain to emit the new "ArchStdEvent" > keyword for common events, but in the end we do not save anything in the > resulting pmu-events.c file. And it requires considerable rework to > support it. > Given that, I would put it very low priority on your todo list, comments? > Cheers, John