Re: [PATCH v4 08/20] sched/fair: load balance only among preferred CPUs

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

Hello Shrikanth,

On 6/17/2026 11:11 PM, Shrikanth Hegde wrote:
> diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
> index d78467ec6ee1..3f3c7f0ca489 100644
> --- a/kernel/sched/fair.c
> +++ b/kernel/sched/fair.c
> @@ -13291,6 +13291,9 @@ static int sched_balance_rq(int this_cpu, struct rq *this_rq,
>  
>  	cpumask_and(cpus, sched_domain_span(sd), cpu_active_mask);
>  
> +	/* Spread load among preferred CPUs */
> +	cpumask_and(cpus, cpus, cpu_preferred_mask);

Since "cpu_preferred_mask" is a subset of "cpu_active_mask", just:

    cpumask_and(cpus, sched_domain_span(sd), cpu_preferred_mask);

is sufficient. We don't need that redundant cpumask_and() with
cpu_active_mask before.

> +
>  	schedstat_inc(sd->lb_count[idle]);
>  
>  redo:

-- 
Thanks and Regards,
Prateek