list_add(&p->list, &old_p->list);
list_add_rcu(&p->list, &old_p->list);
static int __kprobes add_new_kprobe(struct kprobe *old_p, struct kprobe *p){        struct kprobe *kp;	if (p->break_handler) {		list_for_each_entry(kp, &old_p->list, list) {			if (kp->break_handler)				return -EEXIST;		}		list_add_tail(&p->list, &old_p->list);	} else		list_add(&p->list, &old_p->list);	return 0;}