| /* |
| * Copyright (c) 2005, 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 6303187 |
| * @summary Test that no locks are held when a monitor attribute is sampled |
| * or notif delivered. |
| * @author Eamonn McManus |
| * |
| * @run clean CounterMonitorDeadlockTest |
| * @run build CounterMonitorDeadlockTest |
| * @run main CounterMonitorDeadlockTest 1 |
| * @run main CounterMonitorDeadlockTest 2 |
| * @run main CounterMonitorDeadlockTest 3 |
| * @run main CounterMonitorDeadlockTest 4 |
| */ |
| |
| import java.lang.management.ManagementFactory; |
| import java.util.concurrent.atomic.AtomicInteger; |
| import javax.management.JMX; |
| import javax.management.MBeanServer; |
| import javax.management.Notification; |
| import javax.management.NotificationListener; |
| import javax.management.ObjectName; |
| import javax.management.monitor.CounterMonitor; |
| import javax.management.monitor.CounterMonitorMBean; |
| |
| public class CounterMonitorDeadlockTest { |
| |
| public static void main(String[] args) throws Exception { |
| if (args.length != 1) |
| throw new Exception("Arg should be test number"); |
| int testNo = Integer.parseInt(args[0]) - 1; |
| TestCase test = testCases[testNo]; |
| System.out.println("Test: " + test.getDescription()); |
| test.run(); |
| System.out.println("Test passed"); |
| } |
| |
| private static enum When {IN_GET_ATTRIBUTE, IN_NOTIFY}; |
| |
| private static abstract class TestCase { |
| TestCase(String description, When when) { |
| this.description = description; |
| this.when = when; |
| } |
| |
| void run() throws Exception { |
| final MBeanServer mbs = ManagementFactory.getPlatformMBeanServer(); |
| final ObjectName observedName = new ObjectName("a:b=c"); |
| final ObjectName monitorName = new ObjectName("a:type=Monitor"); |
| mbs.registerMBean(new CounterMonitor(), monitorName); |
| final CounterMonitorMBean monitorProxy = |
| JMX.newMBeanProxy(mbs, monitorName, CounterMonitorMBean.class); |
| final TestMBean observedProxy = |
| JMX.newMBeanProxy(mbs, observedName, TestMBean.class); |
| |
| final Runnable sensitiveThing = new Runnable() { |
| public void run() { |
| doSensitiveThing(monitorProxy, observedName); |
| } |
| }; |
| |
| final Runnable nothing = new Runnable() { |
| public void run() {} |
| }; |
| |
| final Runnable withinGetAttribute = |
| (when == When.IN_GET_ATTRIBUTE) ? sensitiveThing : nothing; |
| |
| mbs.registerMBean(new Test(withinGetAttribute), observedName); |
| monitorProxy.addObservedObject(observedName); |
| monitorProxy.setObservedAttribute("Thing"); |
| monitorProxy.setInitThreshold(100); |
| monitorProxy.setGranularityPeriod(10L); // 10 ms |
| monitorProxy.setNotify(true); |
| |
| final int initGetCount = observedProxy.getGetCount(); |
| monitorProxy.start(); |
| |
| System.out.println("Checking GetCount, possible deadlock if timeout."); |
| do { // 8038322. Until timeout of testing harness |
| Thread.sleep(200); |
| } while ((observedProxy.getGetCount()) == initGetCount); |
| System.out.println("Done!"); |
| |
| // This won't show up as a deadlock in CTRL-\ or in |
| // ThreadMXBean.findDeadlockedThreads(), because they don't |
| // see that thread A is waiting for thread B (B.join()), and |
| // thread B is waiting for a lock held by thread A |
| |
| // Now we know the monitor has observed the initial value, |
| // so if we want to test notify behaviour we can trigger by |
| // exceeding the threshold. |
| if (when == When.IN_NOTIFY) { |
| final AtomicInteger notifCount = new AtomicInteger(); |
| final NotificationListener listener = new NotificationListener() { |
| public void handleNotification(Notification n, Object h) { |
| Thread t = new Thread(sensitiveThing); |
| t.start(); |
| try { |
| t.join(); |
| } catch (InterruptedException e) { |
| throw new RuntimeException(e); |
| } |
| notifCount.incrementAndGet(); |
| } |
| }; |
| mbs.addNotificationListener(monitorName, listener, null, null); |
| observedProxy.setThing(1000); |
| System.out.println("Waiting notifCount.get() != 0, possible deadlock if timeout."); |
| do { |
| Thread.sleep(200); |
| } while(notifCount.get() == 0); // 8038322. Until timeout of testing harness |
| System.out.println("Done"); |
| } |
| |
| } |
| |
| abstract void doSensitiveThing(CounterMonitorMBean monitorProxy, |
| ObjectName observedName); |
| |
| String getDescription() { |
| return description; |
| } |
| |
| private final String description; |
| private final When when; |
| } |
| |
| private static final TestCase[] testCases = { |
| new TestCase("Remove monitored MBean within monitored getAttribute", |
| When.IN_GET_ATTRIBUTE) { |
| @Override |
| void doSensitiveThing(CounterMonitorMBean monitorProxy, |
| ObjectName observedName) { |
| monitorProxy.removeObservedObject(observedName); |
| } |
| }, |
| new TestCase("Stop monitor within monitored getAttribute", |
| When.IN_GET_ATTRIBUTE) { |
| @Override |
| void doSensitiveThing(CounterMonitorMBean monitorProxy, |
| ObjectName observedName) { |
| monitorProxy.stop(); |
| } |
| }, |
| new TestCase("Remove monitored MBean within threshold listener", |
| When.IN_NOTIFY) { |
| @Override |
| void doSensitiveThing(CounterMonitorMBean monitorProxy, |
| ObjectName observedName) { |
| monitorProxy.removeObservedObject(observedName); |
| } |
| }, |
| new TestCase("Stop monitor within threshold listener", |
| When.IN_NOTIFY) { |
| @Override |
| void doSensitiveThing(CounterMonitorMBean monitorProxy, |
| ObjectName observedName) { |
| monitorProxy.stop(); |
| } |
| }, |
| }; |
| |
| public static interface TestMBean { |
| public int getThing(); |
| public void setThing(int thing); |
| public int getGetCount(); |
| } |
| |
| public static class Test implements TestMBean { |
| public Test(Runnable runWithinGetAttribute) { |
| this.runWithinGetAttribute = runWithinGetAttribute; |
| } |
| |
| public int getThing() { |
| Thread t = new Thread(runWithinGetAttribute); |
| t.start(); |
| try { |
| t.join(); |
| } catch (InterruptedException e) { |
| throw new RuntimeException(e); |
| } |
| getCount++; |
| return thing; |
| } |
| |
| public void setThing(int thing) { |
| this.thing = thing; |
| } |
| |
| public int getGetCount() { |
| return getCount; |
| } |
| |
| private final Runnable runWithinGetAttribute; |
| private volatile int getCount; |
| private volatile int thing; |
| } |
| } |