extern void destroy_workqueue(struct workqueue_struct *wq);
-struct workqueue_attrs *alloc_workqueue_attrs(gfp_t gfp_mask);
-void free_workqueue_attrs(struct workqueue_attrs *attrs);
-int apply_workqueue_attrs(struct workqueue_struct *wq,
- const struct workqueue_attrs *attrs);
int workqueue_set_unbound_cpumask(cpumask_var_t cpumask);
extern bool queue_work_on(int cpu, struct workqueue_struct *wq,