//******************************************************************************
//
// File: TestSchedule.java
// Package: edu.rit.pj.test
// Unit: Class edu.rit.pj.test.TestSchedule
//
// This Java source file is copyright (C) 2009 by Alan Kaminsky. All rights
// reserved. For further information, contact the author, Alan Kaminsky, at
// ark@cs.rit.edu.
//
// This Java source file is part of the Parallel Java Library ("PJ"). PJ 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 3 of the License, or (at your option) any later version.
//
// PJ 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.
//
// A copy of the GNU General Public License is provided in the file gpl.txt. You
// may also obtain a copy of the GNU General Public License on the World Wide
// Web at http://www.gnu.org/licenses/gpl.html.
//
//******************************************************************************
package edu.rit.pj.test;
import edu.rit.pj.IntegerSchedule;
import edu.rit.util.Range;
import java.util.concurrent.atomic.AtomicLong;
/**
* Class TestSchedule provides a schedule object for testing class {@linkplain
* edu.rit.pj.IntegerSchedule}.
*
* @author Alan Kaminsky
* @version 17-Nov-2009
*/
public class TestSchedule
extends IntegerSchedule
{
// Hidden data members.
// Loop iteration range.
private Range myLoopRange;
// Number of iterations already handed out, N1 (upper 32 bits) plus chunk
// size, N2 (lower 32 bits).
private AtomicLong N1N2 = new AtomicLong();
// Initial chunk size.
private int initN2;
// Chunk size increment.
private int INCR;
// Exported constructors.
/**
* Construct a new test schedule object with an initial chunk size of 1 and
* a chunk size increment of 0.
*/
public TestSchedule()
{
this (1, 0);
}
/**
* Construct a new test schedule object with the given initial chunk size
* and chunk size increment.
*
* @param theInitialChunkSize Initial chunk size.
* @param theChunkSizeIncrement Chunk size increment.
*
* @exception IllegalArgumentException
* (unchecked exception) Thrown if theInitialChunkSize is less
* than 1. Thrown if theChunkSizeIncrement is less than 0.
*/
public TestSchedule
(int theInitialChunkSize,
int theChunkSizeIncrement)
{
super();
if (theInitialChunkSize < 1)
{
throw new IllegalArgumentException
("TestSchedule(): Initial chunk size = " +
theInitialChunkSize + " illegal");
}
if (theChunkSizeIncrement < 0)
{
throw new IllegalArgumentException
("TestSchedule(): Chunk size increment = " +
theChunkSizeIncrement + " illegal");
}
initN2 = theInitialChunkSize;
INCR = theChunkSizeIncrement;
}
/**
* Construct a new test schedule object. This constructor is for use by the
* IntegerSchedule.parse() method. args must be an array
* of two strings, namely the initial chunk size, an integer >= 1, and
* the chunk size increment, an integer >= 0.
*
* @param args Array of argument strings.
*
* @exception IllegalArgumentException
* (unchecked exception) Thrown if args is not an array of two
* strings. Thrown if the initial chunk size is less than 1. Thrown if
* the chunk size increment is less than 0.
*/
public TestSchedule
(String[] args)
{
this (getInitialChunkSize (args), getChunkSizeIncrement (args));
}
private static int getInitialChunkSize
(String[] args)
{
if (args.length != 2)
{
throw new IllegalArgumentException
("TestSchedule(): Usage: -Dpj.schedule=edu.rit.pj.test.TestSchedule or -Dpj.schedule=\"edu.rit.pj.test.TestSchedule(,)\"");
}
int theInitialChunkSize;
try
{
theInitialChunkSize = Integer.parseInt (args[0]);
}
catch (NumberFormatException exc)
{
throw new IllegalArgumentException
("TestSchedule(): Initial chunk size = " + args[0] +
" illegal");
}
return theInitialChunkSize;
}
private static int getChunkSizeIncrement
(String[] args)
{
if (args.length != 2)
{
throw new IllegalArgumentException
("TestSchedule(): Usage: -Dpj.schedule=edu.rit.pj.test.TestSchedule or -Dpj.schedule=\"edu.rit.pj.test.TestSchedule(,)\"");
}
int theChunkSizeIncrement;
try
{
theChunkSizeIncrement = Integer.parseInt (args[1]);
}
catch (NumberFormatException exc)
{
throw new IllegalArgumentException
("TestSchedule(): Chunk size increment = " + args[0] +
" illegal");
}
return theChunkSizeIncrement;
}
// Exported operations.
/**
* Determine if this schedule is a fixed schedule. For a parallel team with
* K threads, a fixed schedule partitions the loop index range into
* exactly K chunks, one chunk for each thread, each chunk with
* predetermined upper and lower bounds.
*
* @return True if this is a fixed schedule, false otherwise.
*/
public boolean isFixedSchedule()
{
return false;
}
// Hidden operations.
/**
* Start a parallel for loop using this schedule.
*
* The start() method is only called by a single thread in the
* Parallel Java middleware.
*
* @param K Number of threads in the parallel team.
* @param theLoopRange Range of iterations for the entire parallel for
* loop. The stride may be 1 or greater.
*/
public void start
(int K,
Range theLoopRange)
{
myLoopRange = theLoopRange;
N1N2.set (initN2 & 0x00000000FFFFFFFFL);
}
/**
* Obtain the next chunk of iterations for the given thread index. If there
* are more iterations, a range object is returned whose lower bound, upper
* bound, and stride specify the chunk of iterations to perform. The
* returned range object's stride is the same as that given to the
* start() method. The returned range object's lower bound and
* upper bound are contained within the range given to the start()
* method. If there are no more iterations, null is returned.
*
* The next() method is called by multiple parallel team threads in
* the Parallel Java middleware. The next() method must be multiple
* thread safe.
*
* @param theThreadIndex Thread index in the range 0 .. K-1.
*
* @return Chunk of iterations, or null if no more iterations.
*/
public Range next
(int theThreadIndex)
{
for (;;)
{
long oldN1N2 = N1N2.get();
int oldN1 = (int) (oldN1N2 >>> 32);
int oldN2 = (int) oldN1N2;
Range result = myLoopRange.chunk (oldN1, oldN2);
int N = result.length();
if (N == 0) return null;
int newN1 = oldN1 + N;
int newN2 = oldN2 + INCR;
long newN1N2 =
((newN1 & 0x00000000FFFFFFFFL) << 32) |
(newN2 & 0x00000000FFFFFFFFL);
if (N1N2.compareAndSet (oldN1N2, newN1N2)) return result;
}
}
}
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