Re: [PATCH] s390: Add support for z13

On Wed, Oct 12 2016, Michael Petlan wrote:

> On Wed, 5 Oct 2016, Andreas Arnez wrote:
>> On Tue, Oct 04 2016, Michael Petlan wrote:
>>
>>> Hi Andreas,
>>>
>>> have you or anyone tested this patch and/or s390 oprofile support
>>> in general? I'd love to know more about the results or at least,
>>> if there any, what has been tested and what not + whether there
>>> are any known issues regarding to HW sampling on s390.
>>
>> IIRC, I just performed a quick smoke test before submitting this patch;
>> and oprofile didn't crash.  Other than that, I don't really know what
>> works and what doesn't.
>>
>
> Could you please try it with setting /proc/sys/kernel/kptr_restrict to '0'
> and /proc/sys/kernel/perf_event_paranoid to '-1', being logged as root user?

Sure, I'll probably try this tomorrow.

[...]

>> * The --help/--usage options of operf and ocount behave strangely.
>>  E.g., they attempt perf_open and just emit a cryptic error message if
>>  that fails.  And upon success they still yield exit code 1.
>
> Maybe if /proc/sys/kernel/perf_event_paranoid is '2' and the user is not
> root, this might happen.

Right.  The complaint is about the cryptic error message and the fact
that not even --help/--usage works in this case.

--
Andreas


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