最近在折腾一块老板子,修改其bsp使其支持clock event & clock src, 但是在timekeeping卡住了, 时钟中断会在update_wall_time里面, 更新墙上时间,其中 /** 752 * update_wall_time - Uses the current clocksource to increment the wall time 753 * 754 * Called from the timer interrupt, must hold a write on xtime_lock. 755 */ 756 void update_wall_time(void) 757 { 758 struct clocksource *clo...
by duanius - 内核源码 - 2012-08-10 15:37:04 阅读(1482) 回复(3)
kernel-2.6.22中的arm arch加入了对dynticks, clocksource/event支持. imx31的BSP在clock这里有一些改动. 找了些kernel clock及timer子系统近来的变化, 总结一下. 一般来说Soft-Timer (timer wheel / hrtimer) 都是由Hardware-Timer(时钟中断之类)以及相关的clock source(e.g GPT in Soc)驱动, 所以我打算先从clock这层开始介绍, 接着是soft-timer, kernel timekeeping, 最后来看一些应用. Clock Sourceclock source定义...
http://www.vmware.com/pdf/vmware_timekeeping.pdf This document includes the following topics: “timekeeping Basics” on page 1 “Time and Frequency Units” on page 4 “PC Timer Hardware” on page 4 “VMware Timer Virtualization” on page 6 “timekeeping in Specific Operating Systems” on page 10 “Synchronizing Virtual Machines and Hosts with Real Time” on page 14 “Time and Performance Measu...