Re: [PATCH v3 04/21] sched/cache: Make LLC id continuous

[K Prateek Nayak]

Hello Chenyu,

On 2/18/2026 8:52 PM, Chen, Yu C wrote:
>> On a separate note, if we add a dependency on SCHED_MC for SCHED_CACHE,
>> we can simply look at cpu_coregroup_mask() and either allocate a new
>> llc_id / borrow llc id  in sched_cpu_activate() when CPU is onlined or
>> reassign them in sched_cpu_deactivate() if an entire LLC is offlined.
>>
> 
> Prateek, may I know if you are thinking of updating every CPU's LLC id
> during its hotplug and not update all percpu LLC id in build_sched_domains()?

I was still thinking of build_sched_domains() (or somewhere in the
online and offline path) where we can first simply look at
cpu_coregroup_mask() and decide if we need to traverse all CPUs and
shuffle the IDs.

-- 
Thanks and Regards,
Prateek