Re: [PATCH 1/4] sched/topology: Store root domain CPU capacity sum

[Quentin Perret]

On Wednesday 08 Apr 2020 at 19:03:57 (+0200), Vincent Guittot wrote:
> Or we can do the opposite and only use capacity_orig_of()/rq->cpu_capacity_orig.
> 
> Is there a case where the max cpu capacity changes over time ? So I
> would prefer to use cpu_capacity_orig which is a field of scheduler
> instead of always calling an external arch specific function

Note however that using arch_scale_cpu_capacity() would be more
efficient, especially on non-arm/arm64 systems where it is a
compile-time constant.

It's probably a matter of personal taste, but I find rq->cpu_capacity_orig
superfluous. It wastes space without actually giving you anything no?
Anybody remembers why it was introduced in the first place?

Thanks,
Quentin