Re: [PATCH] cros_ec_spi: Even though we're RT priority, don't bump cpu freq

From: Qais Yousef
Date: Fri Jun 12 2020 - 10:00:38 EST


On 06/12/20 14:47, Quentin Perret wrote:

[...]

> > > > somehow measure whether or not the task is making its deadlines and
> > > > boost the CPU frequency up if deadlines are not being met. I'm sure
> > > > there are fancier ways.
> >
> > You need to use SCHED_DEADLINE then :)
>
> Well, not quite :-)
>
> The frequency selection for DL is purely based on the userspace-provided
> parameters, from which we derive the bandwidth request. But we don't do
> things like 'raise the frequency if the actual runtime gets close to the
> WCET', or anything of the sort. All of that would have to be implemented
> in userspace ATM.

Hmm okay. I am not a deadline expert so sorry if I was misleading. But it's the
only scheduling class that has the concept of deadline.

Cheers

--
Qais Yousef