Linux 内核时钟之oneshot编程

/**  * tick_program_event  */ int tick_program_event(ktime_t expires, int force) {  struct clock_event_device *dev = __this_cpu_read(tick_cpu_device.evtdev);

 if (unlikely(expires.tv64 == KTIME_MAX)) {   /*    * We don't need the clock event device any more, stop it.    */   clockevents_switch_state(dev, CLOCK_EVT_STATE_ONESHOT_STOPPED);   return 0;  }

 if (unlikely(clockevent_state_oneshot_stopped(dev))) {   /*    * We need the clock event again, configure it in ONESHOT mode    * before using it.    */   clockevents_switch_state(dev, CLOCK_EVT_STATE_ONESHOT);  }

 return clockevents_program_event(dev, expires, force); }

下面这些函数会对timer重新编程：

hrtimer_force_reprogram

hrtimer_interrupt

__tick_broadcast_oneshot_control

tick_nohz_restart

tick_nohz_stop_sched_tick

tick_nohz_handler