#! /usr/bin/env stap

# General interval measurement / monitor.  Gives a report of event interval measurement on a
# per-process or systemwide basis.
# 
# Invoke with a list of probe point patterns as script command-line arguments:
# stap measureinterval.stp 'measurement' 'match' 'accumulation' 'start_event(s)' 'end_event(s)'
#

global interval%, acc%

probe $4
{
  measure = $1
  if ($2 in interval) {
    acc[%($# >= 6 %? $6 %: 0 %)] <<< measure - interval[$2]
  }
  interval[$2] = measure;
}

# optional end of pipeline probe
probe %($# >= 5 %? $5 %: never %)
{
  measure = $1
  if ($2 in interval) {
    acc[%($# >= 6 %? $6 %: 0 %)] <<< measure - interval[$2]
    delete interval[$2]
  }
}

function report()
{
  print("\n");
  foreach(i+ in acc){
     printdln("=", "id", i)
     println($3(acc[i]))
  }
}

probe end {report()}