Re: [PATCH v2 1/5] smp: don't declare nr_cpu_ids if NR_CPUS == 1

[Yury Norov]

On Tue, Sep 06, 2022 at 10:53:53AM +0200, Peter Zijlstra wrote:
> On Mon, Sep 05, 2022 at 04:08:16PM -0700, Yury Norov wrote:
> > SMP and NR_CPUS are independent options, hence nr_cpu_ids may be
> > declared even if NR_CPUS == 1, which is useless.
> 
> I'm thikning you're fixing the wrong problem here.

I'm removing dead code. If NR_CPUS == 1, nr_cpu_ids does exist, exported
as an interface variable, but never normally reached, because in some
other piece of code (not even in smp.h) it's declared conditionally. 

> Also who the heck
> cares about SMP=y NR_CPUS=1 anyway?

Build bots.

> Why do we need extra source complexity for this?

To have effective code generation for UP builds.