Re: [RFC PATCH 12/20] kthread: Implement preferred affinity

[Frederic Weisbecker <frederic@kernel.org>]

Le Fri, Jul 26, 2024 at 11:56:48PM +0200, Frederic Weisbecker a écrit :
> +int kthread_affine_preferred(struct task_struct *p, const struct cpumask *mask)
> +{
> +	struct kthread *kthread = to_kthread(p);
> +	cpumask_var_t affinity;
> +	unsigned long flags;
> +	int ret;
> +
> +	if (!wait_task_inactive(p, TASK_UNINTERRUPTIBLE) || kthread->started) {
> +		WARN_ON(1);
> +		return -EINVAL;
> +	}
> +
> +	if (!zalloc_cpumask_var(&affinity, GFP_KERNEL))
> +		return -ENOMEM;
> +
> +	kthread->preferred_affinity = kzalloc(sizeof(struct cpumask), GFP_KERNEL);
> +	if (!kthread->preferred_affinity) {
> +		ret = -ENOMEM;
> +		goto out;
> +	}
> +
> +	mutex_lock(&kthreads_hotplug_lock);
> +	cpumask_copy(kthread->preferred_affinity, mask);
> +	list_add_tail(&kthread->hotplug_node, &kthreads_hotplug);
> +	kthread_fetch_affinity(kthread, affinity);
> +
> +	/* It's safe because the task is inactive. */
> +	raw_spin_lock_irqsave(&p->pi_lock, flags);
> +	do_set_cpus_allowed(p, mask);

s/mask/affinity