Re: [RFCv7 PATCH 03/10] sched: scheduler-driven cpu frequency selection

From: Rafael J. Wysocki
Date: Thu Feb 25 2016 - 16:03:00 EST


On Thursday, February 25, 2016 10:21:50 AM Peter Zijlstra wrote:
> On Thu, Feb 25, 2016 at 04:55:57AM +0100, Rafael J. Wysocki wrote:
> > Well, I'm not familiar with static keys and how they work, so you'll need to
> > explain this part to me.
>
> See include/linux/jump_label.h, it has lots of text on them. There is
> also Documentation/static-keys.txt

Thanks for the pointers!

It looks like the author of the $subject patch hasn't looked at the latter
document lately.

In any case, IMO this might be used to hide the cpufreq_update_util() call
sites from the scheduler code in case no one has set anything via
cpufreq_set_update_util_data() for any CPUs.

That essentially is when things like the performance governor are in use,
so may be worth doing, but that's your judgement call mostly. :-)

Thanks,
Rafael