On Thu, Jan 6, 2022 at 5:23 PM Borislav Petkov <bp@xxxxxxxxx> wrote: > > On Thu, Jan 06, 2022 at 05:12:51PM +0100, Rafael J. Wysocki wrote: > > And why can't it be a real use case? > > You mean there's someone out there running SMP=n kernels on current > hardware which has CPPC too? Yeah, right. > > > 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. > > Yah, I saw that. And that's why I'm saying CPPC should depend on SMP - > because it needs that functionality which is defined there. In fact, the CPPC code itself doesn't need that functionality. The init_freq_invariance_cppc() call is in there, because amd_set_max_freq_ratio() depends on CPPC and it is pointless to run it when CPPC is not supported, not the other way around. > But if you really wanna support SMP=n, I don't care that much to debate > this more - I just think it is silly. Well, I just don't want to stop supporting SMP=n just because we can't possibly get our build dependencies right.