#! /usr/bin/env stap

/*
 * Copyright (C) 2006-2007 Red Hat Inc.
 * 
 * This copyrighted material is made available to anyone wishing to use,
 * modify, copy, or redistribute it subject to the terms and conditions
 * of the GNU General Public License v.2.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 * Print out the amount of time spent in the nanosleep and compat_nanosleep
 * systemcalls. This can help find which processes are waking based on time
 * rather than some real event than needs to be handled.
 *
 * Format is:
 * 12799538 3389 (xchat) nanosleep: 9547
 * 12846944 2805 (NetworkManager) nanosleep: 100964
 * 12947924 2805 (NetworkManager) nanosleep: 100946
 * 13002925 4757 (sleep) nanosleep: 13000717
 */

global start
global entry_nanosleep

function timestamp:long() {
  return gettimeofday_us() - start
}

function proc:string() {
  return sprintf("%d (%s)", pid(), execname())
}

probe begin {
 start = gettimeofday_us()
}

probe syscall.nanosleep,
  syscall.clock_nanosleep ?,
  syscall.compat_nanosleep ?
{
  t = gettimeofday_us(); p = pid()
  entry_nanosleep[p] = t
}

probe syscall.nanosleep.return,
  syscall.clock_nanosleep.return ?,
  syscall.compat_nanosleep.return ?
{
  if (pid() in entry_nanosleep) {
    elapsed_time = gettimeofday_us() - entry_nanosleep[pid()]
    printf("%d %s %s: %d\n",  timestamp(), proc(), name, elapsed_time)
  }
}