hist_time
struct perf_time_interval hist_time;
if (sched->hist_time.start == 0 && t >= ptime->start)
sched->hist_time.start = t;
sched->hist_time.end = t;
u64 hist_time = sched->hist_time.end - sched->hist_time.start;
printf(" msec (%6.2f%%)\n", 100.0 * r->total_run_time / hist_time);
print_sched_time(hist_time, 2);
.time = hist_time(sample->time),