Function run_timer_process_jif

timer.c:619–698

}

static void run_timer_process_jif(void)
{
	unsigned int multiple;
	unsigned int umultiple;
	unsigned int cnt;
	unsigned int ucnt;
	struct timeval o_tv;
	struct timeval tv;
	struct timeval sync_ts, last_ts;
	stime_t interval, drift;
	utime_t last_ticks, last_sync = 0;

	o_tv.tv_sec = 0;
	o_tv.tv_usec = ITIMER_TICK; /* internal timer */
	multiple  = ((TIMER_TICK*1000000)) / (UTIMER_TICK);
	umultiple = (UTIMER_TICK) / (ITIMER_TICK);

	LM_DBG("tv = %ld,  %ld, m=%d, mu=%d\n",
		(long)o_tv.tv_sec,(long)o_tv.tv_usec,multiple,umultiple);

	gettimeofday(&last_ts, 0);
	last_ticks = *ijiffies;

	for( cnt=1,ucnt=1 ; ; ucnt++ ) {
		tv = o_tv;
		select( 0, 0, 0, 0, &tv);

		/* update internal timer */
		*(ijiffies)+=ITIMER_TICK;

		/* update public utimer */
		if (ucnt==umultiple) {
			*(ujiffies)+=UTIMER_TICK;
			/* no overflow test as even if we go for 1 microsecond tick,
			 * this will happen in 14038618 years :P */
			ucnt = 0;

			cnt++;
			/* update public timer */
			if (cnt==multiple) {
				*(jiffies)+=TIMER_TICK;
				/* test for overflow (if tick= 1s =>overflow in 136 years)*/
				cnt = 0;
			}
		}

		/* synchronize with system time if needed */
		if (*ijiffies - last_sync >= TIMER_SYNC_TICKS) {
			last_sync = *ijiffies;

			gettimeofday(&sync_ts, 0);
			interval = (utime_t)sync_ts.tv_sec*1000000 + sync_ts.tv_usec
						- (utime_t)last_ts.tv_sec*1000000 - last_ts.tv_usec;

			drift = interval - (*ijiffies - last_ticks);

			/* protect against sudden time changes */
			if (interval < 0 || drift < 0 || drift > TIMER_SYNC_TICKS) {