Re: [PATCH v3 6/7] x86/smpboot: introduce per-cpu variable for HT siblings

[Thomas Gleixner]

On Thu, 27 Jun 2019, Thomas Gleixner wrote:

> On Wed, 26 Jun 2019, subhra mazumdar wrote:
> 
> > Introduce a per-cpu variable to keep the number of HT siblings of a cpu.
> > This will be used for quick lookup in select_idle_cpu to determine the
> > limits of search.
> 
> Why? The number of siblings is constant at least today unless you play
> silly cpu hotplug games. A bit more justification for adding yet another
> random storage would be appreciated.
> 
> > This patch does it only for x86.
> 
> # grep 'This patch' Documentation/process/submitting-patches.rst
> 
> IOW, we all know already that this is a patch and from the subject prefix
> and the diffstat it's pretty obvious that this is x86 only.
> 
> So instead of documenting the obvious, please add proper context to justify
> the change.

Aside of that the right ordering is to introduce the default fallback in a
separate patch, which explains the reasoning and then in the next one add
the x86 optimized version.

Thanks,

	tglx