커 널 타이머 timerlist 사용

       ：
a. data:            ，             ，     timer  。
b. expires:        ， linux jiffies   。
c. void (*function)(unsigned long):         。

a. init_timer(struct timer_list*):        ；
b. add_timer(struct timer_list*):        ；
c. mod_timer(struct timer_list *, unsigned long jiffier_timerout):           jiffies_timerout;
d. timer_pending(struct timer_list *):       ，               1，    0；
e. del_timer(struct timer_list*):     。

Linux    jiffies   Windows   TickCount,                ，              。   250 jiffies   ，              ：HZ。        jiffies       ：
unsigned int jiffies_to_msecs(unsigned long);
unsigned int jiffies_to_usecs(unsigned long);
unsigned long msecs_to_jiffies(unsigned int);
unsigned long usecs_to_jiffies(unsigned int);

  ：init_timer->[timer.expires=? & timer.function=?]->add_timer->[mod_timer]->del_timer.

#include 
#include 
#include 
struct timer_list timer;

void timer_handler(unsigned long data) {
    printk(KERN_INFO"timer pending:%d
", timer_pending(&timer));
    mod_timer(&timer, jiffies+msecs_to_jiffies(1000));
    printk(KERN_INFO"jiffies:%ld, data:%ld
", jiffies, data);
}
int timer_init(void) {
    printk(KERN_INFO"%s jiffies:%ld
", __func__, jiffies);
    printk(KERN_INFO"ji:%d,HZ:%d
", jiffies_to_msecs(250), HZ);
    init_timer(&timer);
    timer.data = 45;
    timer.function = timer_handler;
    timer.expires = jiffies + HZ;
    add_timer(&timer);
    printk(KERN_INFO"timer pending:%d
", timer_pending(&timer));
    return 0;
}

void timer_exit(void) {
    printk(KERN_INFO"%s jiffies:%ld
", __func__, jiffies);
    del_timer(&timer);
}

module_init(timer_init);
module_exit(timer_exit);
MODULE_LICENSE("GPL");