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

[Subhra Mazumdar <subhra.mazumdar@oracle.com>]

On 6/26/19 11:54 PM, Thomas Gleixner wrote:
> 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.
OK. I will also add the extra optimization for other architectures.

Thanks,
Subhra
>
> Thanks,
>
> 	tglx