chng_cpu.stp

#! /usr/bin/env stap
/*    Filename: chng_cpu.stp
 *      Author: Ankita Garg <ankita@in.ibm.com>
 * Description: Captures information on the number of times an executable
 * switches cpu
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * Copyright (C) IBM Corp. 2009.  All Rights Reserved.
 *
 */

global threads

probe scheduler.cpu_on
{
  if ((threads[tid()] != cpu() && (execname() == @1))) {
    printf("\nthread %d (%s) context switched on cpu%d state: %d\n",
           tid(), execname(), cpu(), task_state(task_current()));
    print_syms(backtrace());
    threads[tid()] = cpu();
  }
}