#!/usr/bin/env bpftrace
/**
 * Print durations and invocations
 * Call this script with the duration in seconds as argument
 * e.g. bpftrace func_benchmark.bt 30
 */

//tracepoint:sched:sched_wakeup
fentry:try_to_wake_up
{
  if(args->p->mm != 0) {
    @_mms[args->p->mm] = true;
    @_processes[args->p->tgid] = true;
    @_threads[args->p->pid] = true;
  }
}

fentry:task_mm_cid_work
{
  @start[tid] = nsecs;
  @preemptions[tid] = (uint64)0;
}

fexit:task_mm_cid_work
/@start[tid]/
{
  $curr_preemption = @preempted[tid] ? @preemptions[tid] : 0;
  $duration = (nsecs - @start[tid] - $curr_preemption)/1000;
  @durations = lhist($duration, 10, 100, 5);
  @duration_total = stats($duration);
  @duration_max = max($duration);
  delete(@start[tid]);
  delete(@preemptions[tid]);
  delete(@preempted[tid]);
}

/* Support only one preemption, should be fine for non-sleeping functions */
tracepoint:sched:sched_switch
// /@start[args.prev_pid] || @start[args.next_pid]/
{
  if (@start[args.prev_pid]) {
    @preempted[args.prev_pid] = true;
    @preemptions[args.prev_pid] = nsecs;
  }
  if (@start[args.next_pid] && @preempted[args.next_pid]) {
    @preemptions[args.next_pid] = nsecs - @preemptions[args.next_pid];
  }
}

//interval:s:30
interval:s:$1
{
  exit();
}

END
{
  @mms = len(@_mms);
  @processes = len(@_processes);
  @threads = len(@_threads);
  clear(@_mms);
  clear(@_processes);
  clear(@_threads);
  clear(@start);
  clear(@preemptions);
  clear(@preempted);
}