Re: [PATCH v2] x86,sched: allow topologies where NUMA nodes share an LLC

From: Luck, Tony
Date: Mon Mar 26 2018 - 18:45:56 EST


On Mon, Mar 26, 2018 at 03:19:48PM -0700, Alison Schofield wrote:
> On Thu, Mar 22, 2018 at 04:30:29PM -0700, Luck, Tony wrote:
> > On Thu, Mar 22, 2018 at 01:49:22PM -0700, Alison Schofield wrote:
> > > + if (!topology_same_node(c, o) &&
> > > + (c->x86_vendor == X86_VENDOR_INTEL &&
> > > + c->x86_model == INTEL_FAM6_SKYLAKE_X)) {
> >
> > Maybe make life easier in the future to add more models
> > to the list by using x86_match_cpu() here?
> >
> > -Tony
>
> Tony -
> Am I on the right track below?
>
> Define like this:
> static const __initconst struct x86_cpu_id snc_cpu[] = {
> { X86_VENDOR_INTEL, 6, INTEL_FAM6_SKYLAKE_X },
> {}
> };
>
> Use like this:
> if (!topology_same_node(c, o) && x86_match_cpu(snc_cpu)) {

Alison,

Exactly right. You can decide how much of the comment
that was before the "if (!topology_same_node(c, o) ..."
can be moved to before the definition of snc_cpu[]. I'm
too lazy to go back to the original patch to read it, but
I suspect most/all of it would be better descibing the
data structure than cluttering up the code that uses it.

-Tony