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

Rafael J. Wysocki
2025-02-04T15:22:04Z

On Tue, Feb 4, 2025 at 2:07 PM David Arcari <darcari@redhat.com> wrote:
>
>
> Hi Artem,
>
> On 2/4/25 7:23 AM, Artem Bityutskiy wrote:
> > 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"?
>
> The problem with force_acpi is it is very similar to force_use_acpi
> which is what intel_idle.c uses internally:
>
> drivers/idle/intel_idle.c:module_param_named(use_acpi, force_use_acpi,
> bool, 0444);
>
> That said, I am not attached to the 'use_acpi_cst' parameter name.

IMV this is rather about ignoring the built-in states table
altogether, IOW something like "pretend that you don't recognize the
processor".

But it could be something like "prefer_acpi" as far as I'm concerned.