1 /*
   2  * Copyright (c) 2012, 2018, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  */
  23 
  24 /*
  25  * @test
  26  * @bug     7194254
  27  * @summary Creates several threads with different java priorities and checks
  28  *      whether jstack reports correct priorities for them.
  29  *
  30  * @library /test/lib
  31  * @modules java.base/jdk.internal.misc
  32  *          java.management
  33  * @comment Use othervm mode so that we don't capture unrelated threads created by other tests
  34  * @run main/othervm ThreadPriorities
  35  */
  36 
  37 import java.util.ArrayList;
  38 import java.util.concurrent.CyclicBarrier;
  39 import java.util.regex.Matcher;
  40 import java.util.regex.Pattern;
  41 
  42 import jdk.test.lib.process.ProcessTools;
  43 import jdk.test.lib.process.OutputAnalyzer;
  44 import jdk.test.lib.JDKToolFinder;
  45 import static jdk.test.lib.Asserts.*;
  46 
  47 public class ThreadPriorities {
  48 
  49     public static void main(String[] args) throws Throwable {
  50         final int NUMBER_OF_JAVA_PRIORITIES =
  51                 Thread.MAX_PRIORITY - Thread.MIN_PRIORITY + 1;
  52         final CyclicBarrier barrier =
  53                 new CyclicBarrier(NUMBER_OF_JAVA_PRIORITIES + 1);
  54 
  55         for (int p = Thread.MIN_PRIORITY; p <= Thread.MAX_PRIORITY; ++p) {
  56             final int priority = p;
  57             new Thread("Priority=" + p) {
  58                 {
  59                     setPriority(priority);
  60                 }
  61                 public void run() {
  62                     try {
  63                         barrier.await(); // 1st
  64                         barrier.await(); // 2nd
  65                     } catch (Exception exc) {
  66                         // ignore
  67                     }
  68                 }
  69             }.start();
  70         }
  71         barrier.await(); // 1st
  72 
  73         int matches = 0;
  74         ArrayList<String> failed = new ArrayList<>();
  75         ProcessBuilder pb = new ProcessBuilder(
  76                 JDKToolFinder.getJDKTool("jstack"),
  77                 String.valueOf(ProcessTools.getProcessId()));
  78 
  79         String[] output = new OutputAnalyzer(pb.start()).getOutput().split("\\R");
  80 
  81         Pattern pattern = Pattern.compile(
  82                 "\\\"Priority=(\\d+)\\\".* prio=(\\d+).*");
  83         for (String line : output) {
  84             Matcher matcher = pattern.matcher(line);
  85             if (matcher.matches()) {
  86                 matches += 1;
  87                 String expected = matcher.group(1);
  88                 String actual = matcher.group(2);
  89                 if (!expected.equals(actual)) {
  90                     failed.add(line);
  91                 }
  92             }
  93         }
  94         barrier.await(); // 2nd
  95         barrier.reset();
  96 
  97         boolean success = false;
  98         try {
  99             assertEquals(matches, NUMBER_OF_JAVA_PRIORITIES);
 100             assertTrue(failed.isEmpty(), failed.size() + ":" + failed);
 101             success = true;
 102         }
 103         finally {
 104             if (!success) {
 105                 System.out.println("Failure detected - dumping jstack output:");
 106                 for (String line : output) {
 107                     System.out.println(line);
 108                 }
 109             }
 110         } 
 111     }
 112 }
 113