Re: [PATCH 2/2] x86, sched: Fix the undefined reference building error of init_freq_invariance_cppc

[Rafael J. Wysocki]

On Thu, Jan 6, 2022 at 4:55 PM Borislav Petkov <bp@xxxxxxxxx> wrote:
>
> On Thu, Jan 06, 2022 at 10:55:20PM +0800, Huang Rui wrote:
> > I just thought the CPPC function should be able to work on single core even
> > SMP is disabled.
>
> Why, because SMP=n is a real use case?!

And why can't it be a real use case?

> FWIW, we were even speculating on removing SMP=n so how practical is
> using CPPC on SMP=n at all?

The honest answer is that we don't know.

Moreover, AFAICS the requisite #ifdeffery is there already and  the
problem is that the init_freq_invariance_cppc() defined in smpboot.c
is not exported to modules and the CPPC code is modular in this build.