Re: [Eas-dev] [PATCH V4 0/3] sched: cpufreq: Allow remote callbacks

From: Joel Fernandes (Google)
Date: Thu Jul 27 2017 - 23:44:14 EST


On Thu, Jul 27, 2017 at 12:21 AM, Juri Lelli <juri.lelli@xxxxxxx> wrote:
[..]
>> >
>> > But even without that, if you see the routine
>> > init_entity_runnable_average() in fair.c, the new tasks are
>> > initialized in a way that they are seen as heavy tasks. And so even
>> > for the first time they run, freq should normally increase on the
>> > target CPU (at least with above application).i
>>
>> Ok, but the "heavy" in init_entity_runnable_average means for load,
>> not the util_avg. The util_avg is what's used for frequency scaling
>> IIUC and is set to 0 in that function no?
>>
>
> True for init_entity_runnable_average(), but for new task post_init_
> entity_util_avg() is then also called (from wake_up_new_task()), which
> modifies the initial util_avg value (depending on current rq {util,
> load}_avg.

Got it. That makes sense, thank you!

-Joel