linux内核notifier机制 linux通知链

标签：linux内核notifier机制   linux通知链   

struct notifier_block {
     int (*notifier_call)(struct notifier_block *, unsigned long, void *);
     struct notifier_block __rcu *next;
     int priority;
};

static int xxxx_notify(struct notifier_block *nb,
         unsigned long status, void *unused)
{
     int rc;

     if (!the_chip) {
         pr_err("not initialized\n");
         return -EINVAL;
     }

     switch (status) {
     case 0:
         pr_debug("0 received\n");
         break;
     case 1:
         pr_debug("1 received\n");

         break;
     case 2:

         break;
     default:
         pr_err("error received\n");
         break;
     }

     return 0;
};

2：定义alarm_notifier通知链，将上面定义的函数入口赋值给函数指针

notifier_call；

static struct notifier_block xxxx_notifier = {
     .notifier_call = xxxx_notify,
};

     {
     -----
     rc = xxxx_register_notifier(&alarm_notifier);
     if (rc) {
         pr_err("unable to register alarm notifier rc=%d\n", rc);
         return rc;
     ------
     }

int xxxx_register_notifier(struct notifier_block *nb)
{
     -------
     rc = srcu_notifier_chain_register(&chip->irq_notifier_list, nb);
     -------
     return rc;
}
EXPORT_SYMBOL(xxxx_register_notifier);

static void xxxx_isr_work(struct work_struct *work)
{
     struct xxxx_chip *chip
         = container_of(work, struct xxxx_chip, irq_work);
     int status;

     if (!chip)
         return;

     status = xxxx_status_read();

     srcu_notifier_call_chain(&chip->irq_notifier_list,
                         status, NULL);

}

linux内核notifier机制 linux通知链

标签：linux内核notifier机制   linux通知链   

原文地址：http://blog.csdn.net/linux_devices_driver/article/details/39504063