Re: [PATCH 1/3] sched/fair: Prepare variables for increased precision of EAS estimated energy

From: Lukasz Luba
Date: Wed Jun 30 2021 - 13:29:07 EST




On 6/30/21 6:01 PM, Rafael J. Wysocki wrote:
On Fri, Jun 25, 2021 at 5:26 PM Lukasz Luba <lukasz.luba@xxxxxxx> wrote:

The Energy Aware Scheduler (EAS) tries to find best CPU for a waking up
task. It probes many possibilities and compares the estimated energy values
for different scenarios. For calculating those energy values it relies on
Energy Model (EM) data and em_cpu_energy(). The precision which is used in
EM data is in milli-Watts (or abstract scale), which sometimes is not
sufficient. In some cases it might happen that two CPUs from different
Performance Domains (PDs) get the same calculated value for a given task
placement, but in more precised scale, they might differ. This rounding
error has to be addressed. This patch prepares EAS code for better
precision in the coming EM improvements.

Signed-off-by: Lukasz Luba <lukasz.luba@xxxxxxx>

If you want me to pick up this series, this patch requires an ACK from
the scheduler maintainers.


It would be great, if you could take it after e.g. Peter ACK it.

Peter could you have a look at it, please?
In this patch 1/3 we have only variables upgrade.

Regards,
Lukasz