| /* |
| * Copyright (c) 2006, 2015, Oracle and/or its affiliates. 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| /* |
| * @test |
| * @bug 6475157 |
| * @summary Tests deadlock in simultaneous connection and connector-server close |
| * @author Eamonn McManus |
| */ |
| |
| /* This test is somewhat dependent on implementation details. If it suddenly |
| * starts failing after a rewrite of the RMIConnectorServer code, you should |
| * consider whether it is still relevant. |
| */ |
| |
| import java.io.IOException; |
| import java.lang.management.ManagementFactory; |
| import java.lang.management.ThreadInfo; |
| import java.lang.management.ThreadMXBean; |
| import java.util.concurrent.Exchanger; |
| import javax.management.MBeanServer; |
| import javax.management.remote.JMXServiceURL; |
| import javax.management.remote.rmi.RMIConnection; |
| import javax.management.remote.rmi.RMIConnectorServer; |
| import javax.management.remote.rmi.RMIJRMPServerImpl; |
| |
| public class ConnectorStopDeadlockTest { |
| private static String failure; |
| private static RMIConnectorServer connectorServer; |
| |
| public static void main(String[] args) throws Exception { |
| JMXServiceURL url = new JMXServiceURL("service:jmx:rmi://"); |
| MBeanServer mbs = ManagementFactory.getPlatformMBeanServer(); |
| RMIJRMPServerImplSub impl = new RMIJRMPServerImplSub(); |
| |
| System.out.println("Creating connectorServer"); |
| connectorServer = new RMIConnectorServer(url, null, impl, mbs); |
| System.out.println("Starting connectorServer"); |
| connectorServer.start(); |
| System.out.println("Making client"); |
| RMIConnection cc = impl.newClient(null); |
| System.out.println("Closing client"); |
| cc.close(); |
| if (connectorServer.isActive()) { |
| System.out.println("Stopping connectorServer"); |
| connectorServer.stop(); |
| } |
| if (failure == null) |
| System.out.println("TEST PASSED, no deadlock"); |
| else |
| System.out.println("TEST FAILED"); |
| } |
| |
| static void fail(Throwable e) { |
| System.out.println("FAILED WITH EXCEPTION: " + e); |
| e.printStackTrace(System.out); |
| failure = e.toString(); |
| } |
| |
| static void fail(String s) { |
| System.out.println("FAILED: " + s); |
| failure = s; |
| } |
| |
| // static MonitorInfo[] threadLocks(Thread t) { |
| // ThreadMXBean tm = ManagementFactory.getThreadMXBean(); |
| // ThreadInfo[] tis = tm.getThreadInfo(new long[] {t.getId()}, true, true); |
| // if (tis[0] == null) |
| // return null; |
| // else |
| // return tis[0].getLockedMonitors(); |
| // } |
| // |
| // static void showLocks(Thread t) { |
| // System.out.println("Locks for " + t.getName() + ":"); |
| // MonitorInfo[] mis = threadLocks(t); |
| // if (mis == null) |
| // System.out.println(" (no longer exists)"); |
| // else if (mis.length == 0) |
| // System.out.println(" (none)"); |
| // else { |
| // for (MonitorInfo mi : mis) |
| // System.out.println(" " + mi); |
| // } |
| // } |
| |
| // Wait until thread t blocks waiting for a lock held by the calling thread, |
| // or until it exits. |
| static void waitForBlock(Thread t) { |
| Thread currentThread = Thread.currentThread(); |
| System.out.println("waiting for thread " + t.getName() + " to block " + |
| "on a lock held by thread " + currentThread.getName()); |
| ThreadMXBean tm = ManagementFactory.getThreadMXBean(); |
| while (true) { |
| ThreadInfo ti = tm.getThreadInfo(t.getId()); |
| if (ti == null) { |
| System.out.println(" thread has exited"); |
| return; |
| } |
| if (ti.getLockOwnerId() == currentThread.getId()) { |
| System.out.println(" thread now blocked"); |
| return; |
| } |
| Thread.yield(); |
| } |
| } |
| |
| public static class RMIJRMPServerImplSub extends RMIJRMPServerImpl { |
| RMIJRMPServerImplSub() throws IOException { |
| super(0, null, null, null); |
| } |
| |
| public RMIConnection makeClient() throws IOException { |
| return super.makeClient("connection id", null); |
| } |
| |
| @Override |
| protected void clientClosed(RMIConnection conn) throws IOException { |
| System.out.println("clientClosed, will call connectorServer.stop"); |
| final Exchanger<Void> x = new Exchanger<Void>(); |
| Thread t = new Thread() { |
| public void run() { |
| try { |
| connectorServer.stop(); |
| } catch (Exception e) { |
| fail(e); |
| } |
| } |
| }; |
| t.setName("connectorServer.stop"); |
| t.start(); |
| waitForBlock(t); |
| /* If this thread is synchronized on RMIServerImpl, then |
| * the thread that does connectorServer.stop will acquire |
| * the clientList lock and then block waiting for the RMIServerImpl |
| * lock. Our call to super.clientClosed will then deadlock because |
| * it needs to acquire the clientList lock. |
| */ |
| System.out.println("calling super.clientClosed"); |
| System.out.flush(); |
| super.clientClosed(conn); |
| } |
| } |
| } |