Re: [RFC PATCH v3 05/10] sched/topology: Reference the Energy Model of CPUs when available

[Peter Zijlstra]

On Mon, May 21, 2018 at 03:25:00PM +0100, Quentin Perret wrote:
> In order to use EAS, the task scheduler has to know about the Energy
> Model (EM) of the platform. This commit extends the scheduler topology
> code to take references on the frequency domains objects of the EM
> framework for all online CPUs. Hence, the availability of the EM for
> those CPUs is guaranteed to the scheduler at runtime without further
> checks in latency sensitive code paths (i.e. task wake-up).

I'm confused by this patch,... what does it do? Why is em_cpu_get()
(after you fix it) not sufficient?