Re: [PATCH v3 1/6] cpufreq: schedutil: reset sg_cpus's flags at IDLE enter

[Dietmar Eggemann]

On 12/07/2017 01:45 PM, Patrick Bellasi wrote:
> Hi Viresh,
>
> On 07-Dec 10:31, Viresh Kumar wrote:
> > On 30-11-17, 11:47, Patrick Bellasi wrote:

[...]

> > We posted some comments on V2 for this particular patch suggesting
> > some improvements. The patch hasn't changed at all and you haven't
> > replied to few of those suggestions as well. Any particular reason for
> > that?
>
> You right, since the previous posting has been a long time ago, with
> this one I mainly wanted to refresh the discussion. Thanks for
> highlighting hereafter which one was the main discussion points.
>
>
> > For example:
> > - I suggested to get rid of the conditional expression in
> >    cpufreq_schedutil.c file that you have added.
>
> We can probably set flags to SCHED_CPUFREQ_IDLE (instead of resetting
> them), however I think we still need an if condition somewhere.
>
> Indeed, when SCHED_CPUFREQ_IDLE is asserted we don't want to trigger
> an OPP change (reasons described in the changelog).
>
> If that's still a goal, then we will need to check this flag and bail
> out from sugov_update_shared straight away. That's why I've added a
> check at the beginning and also defined it as unlikely to have not
> impact on all cases where we call a schedutil update with runnable
> tasks.
>
> Does this makes sense?

IIRC, there was also this question of doing this not only in the shared 
but also in the single case ...

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