| /* |
| * Copyright (c) 2006, 2017, 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 6467152 6716076 6829503 8132550 |
| * @summary deadlock occurs in LogManager initialization and JVM termination |
| * @author Serguei Spitsyn / Hitachi / Martin Buchholz |
| * |
| * @build LoggingDeadlock2 |
| * @run main LoggingDeadlock2 |
| * @key randomness |
| */ |
| |
| /* |
| * |
| * There is a clear deadlock between LogManager.<clinit> and |
| * Cleaner.run() methods. |
| * T1 thread: |
| * The LogManager.<clinit> creates LogManager.manager object, |
| * sets shutdown hook with the Cleaner class and then waits |
| * to lock the LogManager.manager monitor. |
| * T2 thread: |
| * It is started by the System.exit() as shutdown hook thread. |
| * It locks the LogManager.manager monitor and then calls the |
| * static methods of the LogManager class (in this particular |
| * case it is a trick of the inner classes implementation). |
| * It is waits when the LogManager.<clinit> is completed. |
| * |
| * This is a regression test for this bug. |
| */ |
| |
| import java.util.Arrays; |
| import java.util.List; |
| import java.util.Random; |
| import java.util.concurrent.CyclicBarrier; |
| import java.util.concurrent.atomic.AtomicInteger; |
| import java.util.logging.LogManager; |
| import java.io.File; |
| import java.io.IOException; |
| import java.io.InputStream; |
| import java.io.InputStreamReader; |
| import java.io.Reader; |
| import java.util.concurrent.TimeUnit; |
| |
| public class LoggingDeadlock2 { |
| |
| // ask child process to dumpstack after 60secs |
| public static final long DUMP_STACK_FREQUENCY_MS = 60000; |
| |
| // A marker that allows to validate the subprocess output. |
| public static final String MARKER = "$"; |
| |
| public static void realMain(String arg[]) throws Throwable { |
| try { |
| System.out.println(javaChildArgs); |
| ProcessBuilder pb = new ProcessBuilder(javaChildArgs); |
| ProcessResults r = run(pb.start()); |
| equal(r.exitValue(), 99); |
| |
| // output of subprocess should end with "$" |
| final String out = r.out(); |
| final String trailingOutput = out.indexOf(MARKER) > -1 |
| ? out.substring(out.indexOf(MARKER)+MARKER.length()) |
| : out; |
| equal(trailingOutput, ""); |
| equal(r.err(), ""); |
| equal(out.startsWith("JavaChild started"), true); |
| equal(out.endsWith("$"), true); |
| } catch (Throwable t) { unexpected(t); } |
| } |
| |
| public static class JavaChild { |
| public static void main(String args[]) throws Throwable { |
| System.out.println("JavaChild started"); |
| |
| final CyclicBarrier startingGate = new CyclicBarrier(2); |
| final Throwable[] thrown = new Throwable[1]; |
| |
| // Some random variation, to help tickle races. |
| final Random rnd = new Random(); |
| final long seed = rnd.nextLong(); |
| rnd.setSeed(seed); |
| System.out.println("seed=" + seed); |
| final boolean dojoin = rnd.nextBoolean(); |
| final int JITTER = 1024; |
| final int iters1 = rnd.nextInt(JITTER); |
| final int iters2 = JITTER - iters1; |
| final AtomicInteger counter = new AtomicInteger(0); |
| System.out.println("dojoin=" + dojoin); |
| System.out.println("iters1=" + iters1); |
| System.out.println("iters2=" + iters2); |
| |
| Thread exiter = new Thread() { |
| public void run() { |
| try { |
| startingGate.await(); |
| for (int i = 0; i < iters1; i++) |
| counter.getAndIncrement(); |
| System.exit(99); |
| } catch (Throwable t) { |
| t.printStackTrace(); |
| System.exit(86); |
| } |
| }}; |
| exiter.start(); |
| |
| System.out.println("exiter started"); |
| |
| // signal end of verbose output |
| System.out.print(MARKER); |
| System.out.flush(); |
| |
| startingGate.await(); |
| for (int i = 0; i < iters2; i++) |
| counter.getAndIncrement(); |
| // This may or may not result in a first call to |
| // Runtime.addShutdownHook after shutdown has already |
| // commenced. |
| LogManager.getLogManager(); |
| |
| if (dojoin) { |
| exiter.join(); |
| if (thrown[0] != null) |
| throw new Error(thrown[0]); |
| check(counter.get() == JITTER); |
| } |
| } |
| } |
| |
| //---------------------------------------------------------------- |
| // The rest of this test is copied from ProcessBuilder/Basic.java |
| //---------------------------------------------------------------- |
| private static final String javaExe = |
| System.getProperty("java.home") + |
| File.separator + "bin" + File.separator + "java"; |
| private static final String jstackExe = |
| System.getProperty("java.home") + |
| File.separator + "bin" + File.separator + "jstack"; |
| |
| private static final String classpath = |
| System.getProperty("java.class.path"); |
| |
| private static final List<String> javaChildArgs = |
| Arrays.asList(new String[] |
| { javaExe, "-classpath", classpath, |
| "LoggingDeadlock2$JavaChild"}); |
| |
| private static class ProcessResults { |
| private final String out; |
| private final String err; |
| private final int exitValue; |
| private final Throwable throwable; |
| |
| public ProcessResults(String out, |
| String err, |
| int exitValue, |
| Throwable throwable) { |
| this.out = out; |
| this.err = err; |
| this.exitValue = exitValue; |
| this.throwable = throwable; |
| } |
| |
| public String out() { return out; } |
| public String err() { return err; } |
| public int exitValue() { return exitValue; } |
| |
| public String toString() { |
| StringBuilder sb = new StringBuilder(); |
| sb.append("<STDOUT>\n" + out() + "</STDOUT>\n") |
| .append("<STDERR>\n" + err() + "</STDERR>\n") |
| .append("exitValue = " + exitValue + "\n"); |
| if (throwable != null) |
| sb.append(throwable.getStackTrace()); |
| return sb.toString(); |
| } |
| } |
| |
| private static class StreamAccumulator extends Thread { |
| private final InputStream is; |
| private final StringBuilder sb = new StringBuilder(); |
| private Throwable throwable = null; |
| |
| public String result () throws Throwable { |
| if (throwable != null) |
| throw throwable; |
| return sb.toString(); |
| } |
| |
| StreamAccumulator (InputStream is) { |
| this.is = is; |
| } |
| |
| public void run() { |
| try { |
| Reader r = new InputStreamReader(is); |
| int n; |
| while ((n = r.read()) > 0) { |
| sb.append((char)n); |
| |
| // prints everything immediately to System.out so that we can |
| // see the traces even in the event of a test timeout |
| System.out.write((char)n); |
| System.out.flush(); |
| |
| } |
| } catch (Throwable t) { |
| throwable = t; |
| } finally { |
| try { is.close(); } |
| catch (Throwable t) { throwable = t; } |
| } |
| } |
| } |
| |
| /** |
| * If the child process deadlocks, then the parent may fail in timeout. |
| * In that case, we won't have any interesting traces, unless we manage |
| * to get a thread dump from the child. |
| * It is unsure whether obtaining a thread dump from a deadlocked child |
| * will work - but maybe we could see something if the timeout is a false |
| * positive (the child has not deadlocked but hasn't managed to fully start |
| * yet, for instance). |
| * The idea here is to periodically try to obtain a thread dump from the |
| * child, every 60sec - which should be always less than the jtreg timeout. |
| */ |
| private static class TimeoutThread extends Thread { |
| final long ms; |
| final Process process; |
| TimeoutThread(long ms, Process p) { |
| super("TimeoutThread"); |
| setDaemon(true); |
| this.ms = ms; |
| this.process = p; |
| } |
| |
| @Override |
| public void run() { |
| long start = System.nanoTime(); |
| try { |
| while (true) { |
| sleep(ms); |
| System.err.println("Timeout reached: " + ms); |
| if (process.isAlive()) { |
| long pid = process.pid(); |
| ProcessBuilder jstack = new ProcessBuilder(jstackExe, String.valueOf(pid)); |
| System.err.println("Dumping subprocess stack: " + pid); |
| Process p = jstack.inheritIO().start(); |
| p.waitFor(ms, TimeUnit.MILLISECONDS); |
| } else { |
| System.err.println("Process is not alive!"); |
| break; |
| } |
| } |
| } catch (InterruptedException ex) { |
| System.err.println("Interrupted: " + ex); |
| } catch (IOException io) { |
| System.err.println("Failed to get stack from subprocess"); |
| io.printStackTrace(); |
| } |
| } |
| |
| |
| } |
| |
| private static ProcessResults run(Process p) { |
| Throwable throwable = null; |
| int exitValue = -1; |
| String out = ""; |
| String err = ""; |
| |
| StreamAccumulator outAccumulator = |
| new StreamAccumulator(p.getInputStream()); |
| StreamAccumulator errAccumulator = |
| new StreamAccumulator(p.getErrorStream()); |
| |
| try { |
| System.out.println("Waiting for child process to exit"); |
| outAccumulator.start(); |
| errAccumulator.start(); |
| |
| // ask subprocess to dump stack every 60 secs. |
| new TimeoutThread(DUMP_STACK_FREQUENCY_MS, p).start(); |
| |
| exitValue = p.waitFor(); |
| System.out.println("\nChild exited with status: " + exitValue); |
| |
| outAccumulator.join(); |
| errAccumulator.join(); |
| |
| out = outAccumulator.result(); |
| err = errAccumulator.result(); |
| } catch (Throwable t) { |
| throwable = t; |
| } |
| |
| return new ProcessResults(out, err, exitValue, throwable); |
| } |
| |
| //--------------------- Infrastructure --------------------------- |
| static volatile int passed = 0, failed = 0; |
| static void pass() {passed++;} |
| static void fail() {failed++; Thread.dumpStack();} |
| static void fail(String msg) {System.out.println(msg); fail();} |
| static void unexpected(Throwable t) {failed++; t.printStackTrace();} |
| static void check(boolean cond) {if (cond) pass(); else fail();} |
| static void check(boolean cond, String m) {if (cond) pass(); else fail(m);} |
| static void equal(Object x, Object y) { |
| if (x == null ? y == null : x.equals(y)) pass(); |
| else fail(x + " not equal to " + y);} |
| public static void main(String[] args) throws Throwable { |
| try {realMain(args);} catch (Throwable t) {unexpected(t);} |
| System.out.printf("%nPassed = %d, failed = %d%n%n", passed, failed); |
| if (failed > 0) throw new AssertionError("Some tests failed");} |
| } |