Re: [RFC PATCH 0/3] CFS idle injection

Dietmar Eggemann
2015-11-06T18:30:08Z

On 05/11/15 10:12, Peter Zijlstra wrote:
>
> People, trim your emails!
>
> On Wed, Nov 04, 2015 at 08:58:30AM -0800, Jacob Pan wrote:
>
>>> I also like #2 too. Specially now that it is not limited to a specific
>>> platform. One question though, could you still keep the cooling device
>>> support of it? In some systems, it might make sense to enable /
>>> disable idle injections based on temperature.
>
>> One of the key difference between 1 and 2 is that #2 is open loop
>> control, since we don't have CPU c-states info baked into scheduler.
>
> _yet_, there's people working on that. The whole power aware scheduling
> stuff needs that.

Isn't the idle state information (rq->idle_state) already used in
find_idlest_cpu()?

What we use in energy aware scheduling is quite similar but since we're
interested in the index information of the c-state (to access the right
element of the idle_state vectors of the energy model, we added
rq->idle_state_idx. …