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最新rtlinux内核源码

/*
 * POSIX.4 Timers
 *
 * Written by J. Vidal
 * Copyright (C) Dec, 2002 OCERA Consortium.
 *
 * 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 version 2.
 *
 * Programs to test POSIX.4 timers implementation.
 *
 */

 * Name: accuracity.c
 * Description: Measures timer accuracity for both relative 
 * and absolute timer specifications.
 *
 * Procedure: 1.- Create a thread.
 *            2.- Program a periodic timer with some period (relative spec) or 
 *            a one-shot timer for absolute specification. 
 *            3.- Let expire the timer n times. If it is absolute, reprogram each time
 *            the timer by adding the period to the absolute time specification.
 *            4.- After n expirations, calculate the teoric time transcurred (n*period)
 *            and the real (end_time -start_time).
 *            5.- Print the error (difference between the teoric time transcurred 
 *            and the real one)
 *
 * Name: signals_bandwidth.c
 * Description: Measures POSIX.1 Signals bandwidth.
 *                                                  
 * Procedure: 1.- Create two threads, a parent and a child.
 *            2.- During an interval of time send signals between them.
 *            3.- Measure signals send/received per miliseconds.
 *
 *
 * Name: simple_test.c
 * Description: Simple program to test timers API. 
 *
 * Procedure: 1.- Create a user-defined number of tasks.
 *            2.- Make periodic them, with a period of 2 minutes.
 *            3.- Arm timers for each task. The firs tasks arms a
 *            one-shot timer and the others repeating timers with 
 *            an interval of 1 second.
 *            4.- Install a handler for each timer that wakes up each
 *            task every timer expiration.
 *            5.- Check that task period changes (for all tasks but the first)
 *            from 2 minutes to 1 second due to timers expirations and handlers executions.
 * 
 * Name: simple_test.c
 * Description: Simple program to test timers API. 
 *
 * Procedure: 1.- Create a user-defined number of tasks.
 *            2.- Make periodic them, with a period of 2 minutes.
 *            3.- Arm timers for each task. The firs tasks arms a
 *            one-shot timer and the others repeating timers with 
 *            a interval of 1 second.
 *            4.- Install a handler for each timer that wakes up each
 *            task every timer expiration.
 *            5.- Check that task period changes from 2 minutes to 1 second
 *            due to timers expirations and handlers executions.
 * 
 * Name: test.c 
 * Description: This program test RTLinux POSIX.4 timers real-time constraints.
 *              Provides support for testing both CLOCK_REALTIME & CLOCK_MONOTONIC.
 *              Also for system clock on mode ONESHOT or PERIODIC deppending on the 
 *              defines.
 *
 * Procedure: 1.- Create a user-defined number of tasks. 
 *            2.- Set the system clock on mode ONESHOT or PERIODIC.
 *            3.- Schedule them, using RTLinux API or timers & signals.
 *            4.- Analyse test chronograms. 
 *
 *            5.- NOTE: You will observe that the scheduler result using the RTLinux API
 *                and timers + signals, is basically the same.
 *                Also you will observe that test chronogram for timers based on 
 *                CLOCK_MONOTONIC and system clock on mode periodic is not synchronous.
 *                This is OK, since in RTLinux CLOCK_MONOTONIC with system clock on mode 
 *                periodic is different from CLOCK_REALTIME (the one used by the scheduler
 *                and test chronogram)
 *
 *		The monitor directory comes with a patched version of the scheduler that 
 *		informs about tasks activations and executions times. Also provides a 
 *              program (reader) to  get kernel information. You need to place the 
 *              program crono in that directory in order to see the chronograms (available 
 *              from http://bernia.disca.upv.es/rtportal).
 *
 * Name: timers.c
 * Description: Check that a timer can be programed by different threads
 *
 * Procedure: 1.- Create two tasks.
 *            2.- The first time both arm a timer. Only the last is the owner
 *            and therefore the one that will receive notification of timer expiraition.
 *            3.- The handler for that timer wakes up the other task, allowing it to
 *            program an action for the signal of the timer and set the timer.
 *            4.- The proces is repeated printing the time passed since last timer expiration.
 *            5.- Each time the timer is being programmed by a different thread. 
 * 
 * Name: timers.c
 * Description: Check that a timer can be programed by different threads
 *
 * Procedure: 1.- Create two tasks.
 *            2.- The first time boht arm a timer. Only the last is the owner
 *            and therefore the one that will receive notification of timer expiraition.
 *            3.- The handler for that timer wakes up the other task, allowing it to
 *            program an action for the signal of the timer and set the timer.
 *            4.- The proces is repeated printing the time passed since last timer expiration.
 *            5.- Each time the timer is being programmed by a different thread. 
 *