About dynamic switch to offload/nocb on non-server Intel machines

[Joel Fernandes <joel@joelfernandes.org>]

Dear Paul and Frederic,

Len Brown on CC provided a good idea in a meeting on using intel_pstate to
detect if device is a server or a consumer device.

Can we perhaps use this to trigger the offload/nocb mechanisms on consumer
devices / distros? I was thinking the dynamic offload and the "one kernel"
work that Frederic did can be trigger from such detection.

It is true userspace can do the trigger, but maybe it is better to not leave
it to userspace so we'd save power on bad userspaces.

Come to think of it, this can even be done at boot time if we can read the
below state early enough:

> intel_pstate.c demonstrates how to detect a server when ACPI is present:
>
>
>
> #ifdef CONFIG_ACPI
>
>
>
> static bool intel_pstate_acpi_pm_profile_server(void)
>
> {
>
>         if (acpi_gbl_FADT.preferred_profile =3D=3D PM_ENTERPRISE_SERVER |=
|
>
>             acpi_gbl_FADT.preferred_profile =3D=3D PM_PERFORMANCE_SERVER)
>
>                 return true;
>
>
>
>         return false;
>
> }
>