Linux Clocks and interrupts

Transferred from: http://www.ibm.com/developerworks/cn/linux/1307_liuming_linuxtime1/

No matter how complex these hardware is, the Linux kernel requires only two functions:

• One is the function of timing triggering interrupt;
• The other is the ability to maintain and read the current time.

To meet the needs of the application and the kernel itself, the kernel time system must provide the following three basic functions:

• Provide system tick interrupt (drive Scheduler, implement ticks)
• Maintain system time
• Maintenance Software Timers

Linux Clocks and interrupts