jdk/test/java/rmi/transport/dgcDeadLock/DGCDeadLock.java

/* 
 * Copyright 1998-1999 Sun Microsystems, Inc.  All Rights Reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code 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
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
 * CA 95054 USA or visit www.sun.com if you need additional information or
 * have any questions.
 */

/* @test
 * @bug 4118056
 *
 * @summary synopsis: Distributed Garbage Collection Deadlock
 * @author Laird Dornin
 *
 * @library ../../testlibrary
 * @build DGCDeadLock
 * @build Test
 * @build TestImpl
 * @build TestImpl_Stub
 * @run main/othervm/policy=security.policy/timeout=360 DGCDeadLock
 */

/* This test attempts to cause a deadlock between the rmi leaseChecker
 * thread and a thread that is servicing a dgc clean call. Before the
 * fix for this bug was implemented, deadlock could occur when the
 * leaseChecker held the lock on the lease table and the clean thread
 * held the lock on a target x. The clean thread would attempt to get
 * the lock on the leaseTable to do DGCImpl.unregisterTarget and the
 * leaseChecker would attempt to get the lock on x to do
 * Target.vmidDead.  Each thread held a resource that the other thread
 * was attempting to lock.
 *
 * This test causes the above conditions to occur and waits to see if
 * a given set of remote calls finishes "quickly enough."  
 */

import java.rmi.*;
import java.io.*;

public class DGCDeadLock implements Runnable {

    final static public int HOLD_TARGET_TIME = 25000;
    public static int TEST_FAIL_TIME = HOLD_TARGET_TIME + 30000;
    public static boolean finished = false;
    static DGCDeadLock test = new DGCDeadLock();

    static {
	System.setProperty("sun.rmi.transport.cleanInterval", "50");
    }

    static public void main(String[] args) {

	JavaVM testImplVM = null;
    
	System.err.println("\nregression test for 4118056\n");
	TestLibrary.suggestSecurityManager("java.rmi.RMISecurityManager");

        try {
	    String options = " -Djava.security.policy=" + 
		TestParams.defaultPolicy +
		" -Djava.rmi.dgc.leaseValue=500000" + 
		"  -Dsun.rmi.dgc.checkInterval=" + 
		(HOLD_TARGET_TIME - 5000) + "";

	    testImplVM = new JavaVM("TestImpl", options, "");
	    testImplVM.start();

	    synchronized (test) {
		Thread t = new Thread(test);
		t.setDaemon(true);
		t.start();

		// wait for the remote calls to take place
		test.wait(TEST_FAIL_TIME);
	    }

	    if (!finished) {
		TestLibrary.bomb("Test failed, had exception or exercise" + 
					   " routines took too long to " + 
					   "execute");
	    }
	    System.err.println("Test passed, exercises " + 
			       "finished in time.");

        } catch (Exception e) {
	    testImplVM = null;
	    TestLibrary.bomb("test failed", e);
        }
    }

    public void run() {
	try {
	    String echo = null;

	    // give the test remote object time to initialize.
	    Thread.currentThread().sleep(8000);

	    // create a test client
	    Test foo = (Test) Naming.lookup("rmi://:" + 
					    TestLibrary.REGISTRY_PORT + 
					    "/Foo");
	    echo = foo.echo("Hello world");
	    System.err.println("Test object created.");

	    /* give TestImpl time to lock the target in the 
	     * object table and any dirtys finish.
	     */
	    Thread.currentThread().sleep(5000);

	    //unreference "Foo"
	    foo = null;

	    //garbage collect and finalize foo
	    Runtime.getRuntime().gc();  
	    Runtime.getRuntime().runFinalization();  
	    
	    //import "Bar"
	    Test bar = (Test) Naming.lookup("rmi://:" + 
					    TestLibrary.REGISTRY_PORT + 
					    "/Bar");
	    
	    /* infinite loop to show the liveness of Client,
	     * if we have deadlock remote call will not return
	     */
	    try {
		for (int i = 0; i < 500; i++) {  
		    echo = bar.echo("Remote call" + i);
		    Thread.sleep(10);
		}

		// flag exercises finished
		finished = true;

	    } catch (RemoteException e) {
	    }
	    
	} catch (Exception e) {
	    TestLibrary.bomb("test failed", e);
	} finally {
	}
    }
}