timestamp_now
ktime_t timestamp_now;
timestamp_now = *timestamp;
timestamp_now = ktime_get();
delta = ktime_divns(ktime_sub(timestamp_now, iclock_timestamp),
iclock_timestamp = timestamp_now;
ktime_t timestamp_now;
timestamp_now = ktime_get();
delta = ktime_divns(ktime_sub(timestamp_now, iclock_timestamp),
timestamp_now(&tstamp);
timestamp_now(&now);