Re: [PATCH v6 16/30] x86,fs/resctrl: Add and initialize rdt_resource for package scope core monitor

From: Reinette Chatre
Date: Tue Jul 08 2025 - 18:05:51 EST


Hi Tony,

On 6/26/25 9:49 AM, Tony Luck wrote:
> Counts for each Intel telemetry event are periodically sent to one or
> more aggregators on each package where accumulated totals are made
> available in MMIO registers.
>
> Add a new resource for monitoring these events so that CPU hotplug
> notifiers will build domains at the package granularity.

Patch does a bit more than this. This can be expanded to:

Add a new PERF_PKG resource and introduce package level scope for monitoring
these events so that CPU hotplug notifiers can build domains at the package
granularity.

Use the physical package ID available via topology_physical_package_id()
to identify the monitoring domains with package level scope. This enables
user space to use /sys/devices/system/cpu/cpuX/topology/physical_package_id
to identify the monitoring domain a CPU is associated with.

(Please always feel free to improve.)

>
> Signed-off-by: Tony Luck <tony.luck@xxxxxxxxx>
> ---

Patch looks good to me.

Reinette