Re: [PATCH v6 1/5] xen/device-tree: Parse 'cpu-map' node for CPU topology exploration

On 14.07.2026 12:44, Hirokazu Takahashi wrote:
> --- /dev/null
> +++ b/xen/include/xen/cpu-topology.h
> @@ -0,0 +1,34 @@
> +/* SPDX-License-Identifier: GPL-2.0-only */
> +
> +#ifndef XEN_CPU_TOPOLOGY_H
> +#define XEN_CPU_TOPOLOGY_H
> +
> +#include <xen/cpumask.h>
> +
> +#ifdef CONFIG_GENERIC_CPU_TOPOLOGY
> +
> +struct cpu_topology {
> +    cpumask_var_t thread_sibling;

Btw, as this aspect becomes more apparent when looking at patch 2: What is the
relationship of this (i.e. cpu_topology[cpu].thread_sibling) to
per_cpu(cpu_sibling_mask, cpu)? The two ought to be identical, but I can't see
this being guaranteed. And if they were identical, why would both be needed?

> +    cpumask_var_t core_sibling;

Same for this vs the per-CPU cpu_core_mask.

Jan