ktime_add_safe
timer->node.expires = ktime_add_safe(time, delta);
timer->node.expires = ktime_add_safe(time, ns_to_ktime(delta));
timer->node.expires = ktime_add_safe(timer->node.expires, time);
timer->_softexpires = ktime_add_safe(timer->_softexpires, time);
extern ktime_t ktime_add_safe(const ktime_t lhs, const ktime_t rhs);
expires = ktime_add_safe(ktime_get(),
*t = ktime_add_safe(ktime_get(), *t);
start = ktime_add_safe(start, base->get_ktime());
alarm->node.expires = ktime_add_safe(alarm->node.expires, interval);
expires = ktime_add_safe(expires, base->get_ktime());
exp = ktime_add_safe(now, exp);
tim = ktime_add_safe(tim, hrtimer_resolution);
tim = ktime_add_safe(tim, __hrtimer_cb_get_time(base->clockid));
EXPORT_SYMBOL_GPL(ktime_add_safe);
expires = ktime_add_safe(expires, hrtimer_cb_get_time(timer));