Re: [PATCH RFC nohz_full 0/7] v2 Provide infrastructure forfull-system idle

[Andi Kleen]

> I am guessing that you want CONFIG_NO_HZ_FULL to implicitly enable
> the sysidle code so that CONFIG_NO_HZ_FULL_SYSIDLE can be eliminated.
> I will be happy to take that step, but only after I gain full confidence
> in the correctness and performance of the sysidle code.

FWIW if you want useful testing you need to enable it by default
(as part of NO_IDLE_HZ) anyways. Users will most likely pick
whatever is "default" in Kconfig.

> > If you want a switch for testing I would advise a sysctl or sysfs knob
> 
> This would work well for the correctness part, but not for the performance
> part.

What performance part? 

Are you saying this adds so many checks to hot paths that normal runtime
if() with a flag is too expensive?

-Andi
-- 
ak@xxxxxxxxxxxxxxx -- Speaking for myself only.
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