Re: [PATCH v2] PM: EM: Add inotify support when the energy model is updated.

From: Changwoo Min
Date: Sat May 10 2025 - 01:08:11 EST


Thank you, Rafael, for the pointer.

On 5/10/25 01:41, Rafael J. Wysocki wrote:

I have discussed that with Rafael and we have similar view.
The EM debugfs is not the right interface for this purpose.

A better design and mechanism for your purpose would be the netlink
notification. It is present in the kernel in thermal framework
and e.g. is used by Intel HFI
- drivers/thermal/intel/intel_hfi.c
- drivers/thermal/thermal_netlink.c
It's able to send to the user space the information from FW about
the CPUs' efficiency changes, which is similar to this EM modification.

In addition, after this patch

https://lore.kernel.org/linux-pm/3637203.iIbC2pHGDl@xxxxxxxxxxxxx/

which is about to get into linux-next, em_dev_update_perf_domain()
will not be the only place where the Energy Model can be updated.

I am curious about whether the energy mode is likely to be updated more
often with this change. How often the energy model is likely to be
updated is the factor to be considered for the interface and the model
to post-processing the eneergy model (in the BPF schedulers).

Regards,
Changwoo Min


Thanks!
_______________________________________________
Kernel-dev mailing list -- kernel-dev@xxxxxxxxxx
To unsubscribe send an email to kernel-dev-leave@xxxxxxxxxx