Re: [PATCH v2 1/8] x86/CPU/AMD: Save NodeId on AMD-based systems

From: Borislav Petkov
Date: Wed Sep 09 2020 - 14:07:06 EST


On Thu, Sep 03, 2020 at 08:01:37PM +0000, Yazen Ghannam wrote:
> From: Yazen Ghannam <yazen.ghannam@xxxxxxx>
>
> AMD systems provide a "NodeId" value that represents a global ID
> indicating to which "Node" a logical CPU belongs. The "Node" is a
> physical structure equivalent to a Die, and it should not be confused
> with logical structures like NUMA node.

So we said in Documentation/x86/topology.rst that:

"The kernel does not care about the concept of physical sockets because
a socket has no relevance to software. It's an electromechanical
component."

Now, you're talking, AFAIU, about physical components. Why do you need
them?

What is then:

- cpuinfo_x86.phys_proc_id:

The physical ID of the package. This information is retrieved via CPUID
and deduced from the APIC IDs of the cores in the package.

supposed to mean?

Why isn't phys_proc_id != node_id?

And so on and so on.

Please get the nomenclature straight first and then we can talk changes.

Thx.

--
Regards/Gruss,
Boris.

https://people.kernel.org/tglx/notes-about-netiquette