Re: [PATCH] sched/fair: simplify task_numa_find_cpu()

From: Phil Auld

Date: Thu Sep 11 2025 - 17:21:05 EST


On Thu, Sep 11, 2025 at 04:31:35PM -0400 Yury Norov wrote:
> From: Yury Norov (NVIDIA) <yury.norov@xxxxxxxxx>
>
> Use for_each_cpu_and() and drop some housekeeping code.
>
> Signed-off-by: Yury Norov (NVIDIA) <yury.norov@xxxxxxxxx>

The "housekeeping" part threw me off for a second. I was looking for
isolation related code being dropped :)


Reviewed-by: Phil Auld <pauld@xxxxxxxxxx>


> ---
> kernel/sched/fair.c | 7 ++-----
> 1 file changed, 2 insertions(+), 5 deletions(-)
>
> diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
> index 0990ed90c14e..c48c0975fe7a 100644
> --- a/kernel/sched/fair.c
> +++ b/kernel/sched/fair.c
> @@ -2474,11 +2474,8 @@ static void task_numa_find_cpu(struct task_numa_env *env,
> maymove = !load_too_imbalanced(src_load, dst_load, env);
> }
>
> - for_each_cpu(cpu, cpumask_of_node(env->dst_nid)) {
> - /* Skip this CPU if the source task cannot migrate */
> - if (!cpumask_test_cpu(cpu, env->p->cpus_ptr))
> - continue;
> -
> + /* Skip CPUs if the source task cannot migrate */
> + for_each_cpu_and(cpu, cpumask_of_node(env->dst_nid), env->p->cpus_ptr) {
> env->dst_cpu = cpu;
> if (task_numa_compare(env, taskimp, groupimp, maymove))
> break;
> --
> 2.43.0
>
>

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