static void check_stack_usage(void)
{
	static DEFINE_SPINLOCK(low_water_lock);
	static int lowest_to_date = THREAD_SIZE;
	unsigned long free;

	free = stack_not_used(current);

	if (free >= lowest_to_date)
		return;

	spin_lock(&low_water_lock);
	if (free < lowest_to_date) {
		pr_info("%s (%d) used greatest stack depth: %lu bytes left\n",
			current->comm, task_pid_nr(current), free);
		lowest_to_date = free;
	}
	spin_unlock(&low_water_lock);
}
static void check_stack_usage(void)
{
	static DEFINE_SPINLOCK(low_water_lock);
	static int lowest_to_date = THREAD_SIZE;
	unsigned long free;

	free = stack_not_used(current);

	if (free >= lowest_to_date)
		return;

	spin_lock(&low_water_lock);
	if (free < lowest_to_date) {
		pr_info("%s (%d) used greatest stack depth: %lu bytes left\n",
			current->comm, task_pid_nr(current), free);
		lowest_to_date = free;
	}
	spin_unlock(&low_water_lock);
}