102 lines
3.2 KiB
Java
102 lines
3.2 KiB
Java
/*
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* Copyright (c) 2006, 2020, Oracle and/or its affiliates. All rights reserved.
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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*
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* This code is free software; you can redistribute it and/or modify it
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* under the terms of the GNU General Public License version 2 only, as
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* published by the Free Software Foundation.
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*
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* This code is distributed in the hope that it will be useful, but WITHOUT
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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* version 2 for more details (a copy is included in the LICENSE file that
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* accompanied this code).
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*
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* You should have received a copy of the GNU General Public License version
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* 2 along with this work; if not, write to the Free Software Foundation,
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* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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*
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* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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* or visit www.oracle.com if you need additional information or have any
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* questions.
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*/
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/*
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* @test
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* @bug 4994705
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*
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* @summary deadlock in LogManager
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* @author Serguei Spitsyn / SAP
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*
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* @library /test/lib
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* @build LoggingDeadlock
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* @run main/timeout=15 LoggingDeadlock
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* @key randomness
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*/
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/*
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*
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* There can be a deadlock between two class initializations.
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* It happens if the LogManager.<clinit> and the Logger.<clinit>
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* are invoked concurrently on two different threads.
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* There is a cyclic dependence between the two static initializers:
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* 1. LogManager.<clinit> instantiate the class RootLogger which
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* is a subclass of the Logger class.
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* It requires the Logger class initialization to complete.
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* 2. Logger.<clinit> initializes the field "global", so it
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* it makes a call: Logger.getLogger("global").
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* Subsequently the LogManager static method getLogManager()
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* is called which requires the LogManager class
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* initialization to complete.
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* This cyclic dependence causes a deadlock, so two class
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* initializations are waiting for each other.
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* This is a regression test for this bug.
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*/
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import java.util.Random;
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import java.util.logging.LogManager;
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import java.util.logging.Logger;
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import jdk.test.lib.RandomFactory;
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public class LoggingDeadlock {
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private static int preventLoopElision;
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private static final Random random = RandomFactory.getRandom();
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public static void randomDelay() {
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int runs = random.nextInt(1000000);
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int c = 0;
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for (int i = 0; i < runs; ++i) {
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c = c + i;
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}
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preventLoopElision = c;
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}
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public static void main(String[] args) throws InterruptedException{
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Thread t1 = new Thread(new Runnable() {
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public void run() {
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randomDelay();
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// Trigger Logger.<clinit>
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Logger.getAnonymousLogger();
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}
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});
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Thread t2 = new Thread(new Runnable() {
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public void run() {
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randomDelay();
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// Trigger LogManager.<clinit>
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LogManager.getLogManager();
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}
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});
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t1.start();
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t2.start();
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t1.join();
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t2.join();
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System.out.println("\nTest passed");
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}
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}
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