xlog_get_cycle
if (xlog_get_cycle(offset) == 0) {
first_cycle = xlog_get_cycle(offset);
last_cycle = xlog_get_cycle(offset);
mid_cycle = xlog_get_cycle(offset);
cycle = xlog_get_cycle(buf);
first_half_cycle = xlog_get_cycle(offset);
last_half_cycle = xlog_get_cycle(offset);