Re: [PATCH 5/6] cgroup/cpuset: optimize cpuset_mems_allowed_intersects()

[Waiman Long <longman@redhat.com>]

On 5/13/24 18:01, Yury Norov wrote:
> If the function is called with tsk1 == tsk2, we know for sure that their
> mems_allowed nodes do intersect, and so we can return immediately instead
> of checking the nodes content.
>
> Signed-off-by: Yury Norov <yury.norov@gmail.com>
> ---
>   kernel/cgroup/cpuset.c | 3 +++
>   1 file changed, 3 insertions(+)
>
> diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c
> index 4237c8748715..47ed206d4890 100644
> --- a/kernel/cgroup/cpuset.c
> +++ b/kernel/cgroup/cpuset.c
> @@ -5010,6 +5010,9 @@ EXPORT_SYMBOL_GPL(cpuset_mem_spread_node);
>   int cpuset_mems_allowed_intersects(const struct task_struct *tsk1,
>   				   const struct task_struct *tsk2)
>   {
> +	if (tsk1 == tsk2)
> +		return 1;
> +
>   	return nodes_intersects(tsk1->mems_allowed, tsk2->mems_allowed);
>   }
>   
Reviewed-by: Waiman Long <longman@redhat.com>