On Tue, Nov 17, 2020 at 06:19:52PM -0500, Joel Fernandes (Google) wrote:
> +/* Per-task interface */
> +static unsigned long sched_core_alloc_task_cookie(void)
> +{
> + struct sched_core_cookie *ptr =
> + kmalloc(sizeof(struct sched_core_cookie), GFP_KERNEL);
> +
> + if (!ptr)
> + return 0;
> + refcount_set(&ptr->refcnt, 1);
> +
> + /*
> + * NOTE: sched_core_put() is not done by put_task_cookie(). Instead, it
> + * is done after the stopper runs.
> + */
> + sched_core_get();
> + return (unsigned long)ptr;
> +}
> +
> +static bool sched_core_get_task_cookie(unsigned long cookie)
> +{
> + struct sched_core_cookie *ptr = (struct sched_core_cookie *)cookie;
> +
> + /*
> + * NOTE: sched_core_put() is not done by put_task_cookie(). Instead, it
> + * is done after the stopper runs.
> + */
> + sched_core_get();
> + return refcount_inc_not_zero(&ptr->refcnt);
> +}
> +
> +static void sched_core_put_task_cookie(unsigned long cookie)
> +{
> + struct sched_core_cookie *ptr = (struct sched_core_cookie *)cookie;
> +
> + if (refcount_dec_and_test(&ptr->refcnt))
> + kfree(ptr);
> +}
> + /*
> + * NOTE: sched_core_get() is done by sched_core_alloc_task_cookie() or
> + * sched_core_put_task_cookie(). However, sched_core_put() is done
> + * by this function *after* the stopper removes the tasks from the
> + * core queue, and not before. This is just to play it safe.
> + */
So for no reason what so ever you've made the code more difficult?
