RE: [PATCH v3 3/8] x86/resctrl: Add a new node-scoped resource to rdt_resources_all[]

[Luck, Tony]

> To deal with these complexities I would like to consider if it may
> make things simpler to always (irrespective of allocation and
> monitoring scope) maintain allocation and monitoring domain lists.
> Each list need only carry data appropriate to its use ... the allocation
> list only has data relevant to allocation, the monitoring list only
> has data relevant to monitoring. This is the struct rdt_domain related
> split I mentioned previously.
>
> Code could become something like:

resctrl_online_cpu()
{
	...
	for_each_alloc_capable_rdt_resource(r)
		alloc_domain_add_cpu(...)
	for_each_mon_capable_rdt_resource(r)
		mon_domain_add_cpu(...)
	...
}

> This would reduce complication in domain_add_cpu() since each domain list
> only need to concern itself with monitoring or allocation.

This does seem a worthy target.

I started on a patch to so this ... but I'm not sure I have the stamina or the time
to see it through. 

I split struct rdt_domain into rdt_ctrl_domain and rdt_mon_domain. But that
led to also splitting the rdt_hw_domain structure into two, and then splitting
the resctrl_to_arch_dom() function, and then another and another.

That process will eventually converge (there are a finite number of lines
of code) .... but it will be a big patch. I don't see how to stage it a piece
at a time.

-Tony