Re: Adding your java test to The Mauve Java test suite?

[Petter Reinholdtsen <pere at hungry dot com>]

[Bill Pugh]
> Actually, we have a set of three test cases for volatiles, all of
> which should be added to mauve. I'll ask Jeremy (a grad student
> working with me on the Java Memory Model) to get involved in helping
> you with this and preparing versions of all three that work in the
> mauve test harness.

Thanks.  He should get active on the mauve mailinglist, and start
sending patches and new test-cases.

> All three are available at:
> 	http://www.cs.umd.edu/~pugh/java/memoryModel/Volatiles.tar
> 
> It looks like the one below is a valid port of the AtomicLong test.

That is correct.

>> Is it OK
>> with you that I submit this patch for inclusion into Mauve, licensed
>> using the GPL?
> 
> yes, of course, although we should do it right and get all three tests
> in mauve.

Just to make sure the Mauve developers are aware of this test, I copy
this message to the mailing list.  (I hope they accept non-subscriber
postings. :-)


This is a test for the CVS version of Mauve.  I stored it in
'gnu/testlet/java/lang/Long/AtomicLong.java' in my tree.  Please
include it in the Mauve distribution.

//// Test if access to volatile long (64 bit) valuies is atomic.
//
// From an example in Dr. Dobb's Journal june 2002, page 93.

// Copyright (c) 2002  Peter Haggar and Petter Reinholdtsen
// Written by Peter Haggar, and addapted for mauve by Petter
// Reinholdtsen <pere@td.org.uit.no>

// This file is part of Mauve.

// Mauve 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, or (at your option)
// any later version.

// Mauve 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.

// You should have received a copy of the GNU General Public License
// along with Mauve; see the file COPYING.  If not, write to
// the Free Software Foundation, 59 Temple Place - Suite 330,
// Boston, MA 02111-1307, USA.

// Tags: JDK1.0

package gnu.testlet.java.lang.Long;

import gnu.testlet.Testlet;
import gnu.testlet.TestHarness;

public class AtomicLong implements Testlet
{
    static volatile long val;
    static int count = 10000000;
    static volatile boolean failed = false;

    class Runner extends Thread
    {
	long key;
	TestHarness harness;
	
	Runner(int k, TestHarness h)
	{
	    harness = h;

	    long temp = k;
	    // key = 00000001 00000001 for thread 1
	    // key = 00000002 00000002 for thread 2
	    key = (temp << 32) | temp;
	}
	public void run()
	{
	    for (int i = 0; !failed && i < count; i++)
	    {
		// This 64 bit assignment is supposed to be atomic since
		// val is declared atomic
		long temp = val; // temp = 00000001 00000001
		long temp1 = temp >>> 32; // temp1 = 00000000 00000001
		long temp2 = temp << 32; // temp2 = 00000001 00000000
		temp2 = temp2 >>> 32; // temp2 = 00000000 00000001

		if (temp1 != temp2)
		    failed = true;

		// This 64-bit assigment is supposed to be atomic
		// since val is declared volatile.  temp1 should
		// always equal temp2.
		val = key;// val should always = 00000001 00000001 for thread 1
	    }
	}
    }   

  public void test (TestHarness harness)
  {
      final int threadcount = 10;
      try {
	  Thread[] threads = new Thread[threadcount];
	  for (int t = 0; t < threadcount; t++)
	  {
	      threads[t] = new Runner(t + 1, harness);
	      threads[t].start();
	  }
	  for (int t = 0; t < threadcount; t++)
	  {
	      try {
		  threads[t].join();
	      } catch (InterruptedException e) {
		  harness.fail("Error: Unexpected exception " + e);
	      }
	  }
	  harness.check(!failed, "Error: access to 'volatile long' is "+
			"not atomic.");
      } catch (Exception e) {
	  harness.fail("Error: Unexpected exception " + e);
      }
  }
}