Re: [GIT pull] x86/urgent for v5.9-rc2

From: Thomas Gleixner
Date: Mon Aug 31 2020 - 03:13:45 EST


On Sun, Aug 30 2020 at 12:13, Linus Torvalds wrote:
> On Sun, Aug 30, 2020 at 11:04 AM Thomas Gleixner <tglx@xxxxxxxxxxxxx> wrote:
>>
>> The historical inconsistent for_each_cpu() behaviour of
>> ignoring the cpumask and unconditionally claiming that CPU0 is in the
>> mask struck again. Sigh.
>
> I guess we could remove the UP optimizations these days. It's not like
> they matter like they used to.

Indeed.

> Or leave the optimizations in the sense that they wouldn't do the
> crazy bit searching, but they could look at bit 0 of the mask they're
> passed..

Yes, that's trivial enough and the compiler should turn the whole thing
into a simple conditional checking bit 0 and remove the rest of the loop
gunk.

Thanks,

tglx