Re: [PATCH v3] selftests/ftrace: Do not trace do_softirq because of PREEMPT_RT

From: Shuah Khan
Date: Mon Feb 14 2022 - 13:33:25 EST


On 2/14/22 4:19 AM, Sebastian Andrzej Siewior wrote:
On 2022-02-14 09:36:57 [+0100], Krzysztof Kozlowski wrote:
The PREEMPT_RT patchset does not use do_softirq() function thus trying
to filter for do_softirq fails for such kernel:

echo do_softirq
ftracetest: 81: echo: echo: I/O error

Choose some other visible function for the test. The function does not
have to be actually executed during the test, because it is only testing
filter API interface.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxxxxx>
Reviewed-by: Shuah Khan <skhan@xxxxxxxxxxxxxxxxxxx>
Reviewed-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>

Acked-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>

Notes:
I understand that the failure does not exist on mainline kernel (only
with PREEMPT_RT patchset) but the change does not harm it.


Steve,

Would you like me to take this through linux-kselftest next for 5.18-rc1

I am guessing there is no urgency on this - of not I can take this in for
rc5.

thanks,
-- Shuah