LKML Archive on
help / color / mirror / Atom feed
From: John Garry <>
To: Thomas-Mich Richter <>,
	<>, <>
Cc: Peter Zijlstra <>,
	Ingo Molnar <>,
	Arnaldo Carvalho de Melo <>,
	Alexander Shishkin <>,
	Jiri Olsa <>,
	"Namhyung Kim" <>,
	Linuxarm <>, <>,
	Will Deacon <>
Subject: Re: s390 perf events JSONs query
Date: Fri, 20 Apr 2018 14:53:27 +0100	[thread overview]
Message-ID: <> (raw)
In-Reply-To: <>

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
>> 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 

> 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?


  reply	other threads:[~2018-04-20 13:53 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-04-20 10:51 John Garry
2018-04-20 11:44 ` Thomas-Mich Richter
2018-04-20 12:34   ` John Garry
2018-04-20 13:25 ` Thomas-Mich Richter
2018-04-20 13:53   ` John Garry [this message]
2018-04-20 14:13     ` Hendrik Brueckner

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \ \ \ \ \ \ \ \ \ \ \ \ \ \ \
    --subject='Re: s390 perf events JSONs query' \

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).