Function ratecheck

freebsd/kern/kern_time.c:1025–1046

* ratecheck(): simple time-based rate-limit checking. */

 * ratecheck(): simple time-based rate-limit checking.
 */
int
ratecheck(struct timeval *lasttime, const struct timeval *mininterval)
{
	struct timeval tv, delta;
	int rv = 0;

	getmicrouptime(&tv);		/* NB: 10ms precision */
	delta = tv;
	timevalsub(&delta, lasttime);

	/*
	 * check for 0,0 is so that the message will be seen at least once,
	 * even if interval is huge.
	 */
	if (timevalcmp(&delta, mininterval, >=) ||
	    (lasttime->tv_sec == 0 && lasttime->tv_usec == 0)) {
		*lasttime = tv;
		rv = 1;
	}

	return (rv);
}

/*
 * ppsratecheck(): packets (or events) per second limitation.