On 23-01-17, 15:24, Philipp Miedl wrote:

I would say it only checks whether the elapsed time since the last governor
call. My question is whether the call to the governor can be delayed for
such a long time without the CPU going into idle? If it can be guaranteed
that the governor call cannot be delayed without the CPU going to idle than
it is true - otherwise not.

You are using a 4.4 kernel, which used the older delayed work stuff at sampling
rate. This has all changed a lot and we hooks paired with the scheduler now to
do this instead. Things have mostly changed since 4.7. Would it be possible for
you to use a later kernel and see if you still see something wrong?

Now coming back to 4.4, the timers (in the delayed works) can't get delayed but
the work can as it is just another process. But your setup has no almost load
and that seems unlikely as well. So, it looks to be a problem at some other
place. Tracers are your friend, only those can confirm something here.

-- 
viresh