[SRU][G][H][I][UNSTABLE][PATCH 0/1] selftests/ftrace: fix event-no-pid on 1-core machine

[Krzysztof Kozlowski]

On 06/07/2021 10:37, Stefan Bader wrote:
> On 05.07.21 17:47, Krzysztof Kozlowski wrote:
>> BugLink: https://bugs.launchpad.net/bugs/1927749
>>
>> SRU Justification:
>>
>> [Impact]
>>
>> * Kernel selftests ftrace test fails on small machines which makes it
>>    difficult/impossible to spot real ftrace failure.
>> * Only 1-core CPUs are affected.
>> * When running event-no-pid test on small machines (e.g. cloud 1-core
>>    instance), other events might not happen.
>>
>> [Fix]
>>
>> * Schedule a simple sleep task to be sure that some other process events
>>    get recorded.
>> * Fix accepted in mainline (v5.14-rc1 merge window).
>>
>> [Test Plan]
>>
>> * Run ftrace test from kernel selftests.
>>
>> [Where problems could occur]
>>
>> * Only kernel selftests should be affected.
>> * ftrace test can have false positives or negatives.
>>
>> Best regards,
>> Krzysztof
>>
>>
>> Krzysztof Kozlowski (1):
>>    selftests/ftrace: fix event-no-pid on 1-core machine
>>
>>   .../testing/selftests/ftrace/test.d/event/event-no-pid.tc  | 7 +++++++
>>   1 file changed, 7 insertions(+)
>>
> I just noticed that in the submission you say nothing about Focal, but the bug 
> report is having a task for it. Could you clarify please?

Yes, it's not accurate in the bug. It should go to Focal v5.8+ kernels,
so all of these will get it via Groovy. The Focal's v5.4 does not have
this test thus does not need the fix.

Best regards,
Krzysztof