Re: [PATCH v3 3/8] sched/topology: Switch to assigning "sd->shared" from s_data

[K Prateek Nayak <kprateek.nayak@amd.com>]

Hello Chenyu,

On 1/21/2026 8:56 PM, Chen, Yu C wrote:
>> @@ -2655,8 +2655,19 @@ build_sched_domains(const struct cpumask *cpu_map, struct sched_domain_attr *att
>>           unsigned int imb_span = 1;
>>             for (sd = *per_cpu_ptr(d.sd, i); sd; sd = sd->parent) {
>> +            struct sched_domain *parent = sd->parent;
>>               struct sched_domain *child = sd->child;
>>   +            /* Attach sd->shared to the topmost SD_SHARE_LLC domain. */
>> +            if ((sd->flags & SD_SHARE_LLC) &&
>> +                (!parent || !(parent->flags & SD_SHARE_LLC))) {
>> +                int llc_id = cpumask_first(sched_domain_span(sd));
>> +
>> +                sd->shared = *per_cpu_ptr(d.sds, llc_id);
> 
> I agree that in the current implementation, we use the llc_id="first CPU" to
> index into d.sds, and this value actually represents the LLC ID. In the
> cache-aware scheduling, we plan to convert the llc_id to a logical ID that
> is no longer tied to the CPU number. Just 2 cents, to avoid confusion, maybe
> rename the  aforementioned llc_id to sd_id?

Ack! Will modify in the next version!

> 
> Anyway I will run some tests on the entire patch set and provide feedback
> afterward.

Thanks a ton for taking a look at the series! Much appreciated.

-- 
Thanks and Regards,
Prateek