// our total assist time.
		return
	}
	if l.transitioning {
		throw("update during transition")
	}
	l.updateLocked(now)
	l.unlock()
}

// updateLocked is the implementation of update. l.lock must be held.
func (l *gcCPULimiterState) updateLocked(now int64) {
	lastUpdate := l.lastUpdate.Load()
	if now < lastUpdate {
		// Defensively avoid overflow. This isn't even the latest update anyway.