kref_init(&obj->ref);// do something here
// ...kref_get(&obj->ref);
call_something(obj);
kref_put(&obj->ref);// do something here
// ...kref_put(&obj->ref);

struct my_data
{..struct kref refcount;..
};void data_release(struct kref *ref)
{struct my_data *data = container_of(ref, struct my_data, refcount);kfree(data);
}void more_data_handling(void *cb_data)
{struct my_data *data = cb_data;.. do stuff with data here.kref_put(&data->refcount, data_release);
}int my_data_handler(void)
{int rv = 0;struct my_data *data;struct task_struct *task;data = kmalloc(sizeof(*data), GFP_KERNEL);if (!data)return -ENOMEM;kref_init(&data->refcount);kref_get(&data->refcount);task = kthread_run(more_data_handling, data, "more_data_handling");if (task == ERR_PTR(-ENOMEM)) {rv = -ENOMEM;goto out;}.. do stuff with data here.out:kref_put(&data->refcount, data_release);return rv;
}

static DEFINE_MUTEX(mutex);
static LIST_HEAD(q);
struct my_data
{struct kref  refcount;struct list_head link;
};static struct my_data *get_entry()
{struct my_data *entry = NULL;mutex_lock(&mutex);if (!list_empty(&q)) {entry = container_of(q.next, struct my_q_entry, link);kref_get(&entry->refcount);}mutex_unlock(&mutex);return entry;
}static void release_entry(struct kref *ref)
{struct my_data *entry = container_of(ref, struct my_data, refcount);list_del(&entry->link);kfree(entry);
}static void put_entry(struct my_data *entry)
{mutex_lock(&mutex);kref_put(&entry->refcount, release_entry);mutex_unlock(&mutex);
}