Re: [PATCH] intel_idle: introduce 'use_acpi_cst' module parameter

Artem Bityutskiy
2025-02-04T12:23:30Z

Hi David,

On Tue, 2025-01-28 at 09:11 -0500, David Arcari wrote:

> +The ``use_acpi_cst`` module parameter (recognized by ``intel_idle`` if the
> +kernel has been configured with ACPI support) can be set to make the driver
> +ignore the per cpu idle states in lieu of ACPI idle states. ``use_acpi_cst``
> +has no effect if ``no_acpi`` is set).

With this change, there will be three parameters:

* no_acpi
* use_acpi
* use_acpi_cst

I would like to make the naming as intuitive as possible. We do not rename the
first 2, but for the 3rd one, I think "force_acpi" would be a better name. Or
perhaps "no_native"?

* no_acpi - Do not use ACPI at all. Only native mode is available, no ACPI mode.
* use_acpi - No-op in ACPI mode, consult ACPI tables for C-states on/off
status in native mode.
* force_acpi (or no_native?) - Work only in ACPI mode, no native mode available
(ignore all custom tables).

Additionally, I think we should enhance the documentation for 'no_acpi' and
'use_acpi' while we're at it. Otherwise, it is hard to distinguish between these
three options. Would you consider another patch that improves the documentation
for 'no_acpi' and 'use_acpi', and then adds the third parameter?

Thanks, Artem!