高手进阶 Linux系统中内核定时器的应用

[CODE]

#include<linux/init.h>

#include<linux/sched.h>

#include<linux/module.h>

#include<linux/jiffies.h>

#include<asm/io.h>

#include<linux/timer.h>

#include<linux/wait.h>



MODULE_LICENSE("GPL");



static DECLARE_WAIT_QUEUE_HEAD(wq);

static int flag = 0;

struct timer_list my_timer;



void timer_test(unsigned long data)

{

        printk("this is a test\n");

        flag = 1;

        wake_up_interruptible(&wq);

}



static int __init hello_init(void)

{

        init_timer(&my_timer);

        my_timer.expires = jiffies + 5000;

        my_timer.data = 0;

        my_timer.function = timer_test;

        add_timer(&my_timer);

        wait_event_interruptible(wq, flag != 0);

        flag = 0;

        return 0;

}



static void __exit hello_exit(void)

{

        del_timer(&my_timer);

        printk(KERN_ALERT "Goodbye\n");

}



module_init(hello_init);

module_exit(hello_exit);



[/CODE]