Linux内核中的定时器实现及编程

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在Linux内核中,定时器是一种重要的机制,用于在特定的时间间隔内执行某些操作。定时器的实现涉及到管理和触发定时事件的机制,本文将详细介绍Linux内核中定时器的实现和编程方法。

一、定时器的基本概念
定时器是一种用于在指定时间间隔内执行某些任务的机制。在Linux内核中,定时器的实现主要依赖于定时器数据结构和相关的函数。

  1. 定时器数据结构
    在Linux内核中,定时器被定义为struct timer_list结构体。该结构体包含了定时器的相关信息,如超时时间、定时器处理函数等。以下是struct timer_list的定义:
struct timer_list {
   
   
    unsigned long expires;  // 定时器超时时间
    void (*funct
Linux内核编程(九)Linux内核定时器 Linux内核中有一个宏HZ,这个宏用来表示一秒钟对应的节拍的数量。利用Linux内核中的这个宏,我们就可以把时间转换成节拍数。比如,定时一秒钟换成节拍数就是expires=jiffies+1*HZ,其中宏定义jiffies为系统当前时间对应的节拍数。宏HZ的值我们是可以设置的,也就是说一秒钟对应多少个节拍数我们是可以设置的。打开make menuconfig图形化配置界面进行设置,具体设置路径查看其它博客。 阅读详情

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