1 /* 2 * Copyright (c) 2013, 2016, 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 /* @test 25 * @bug 8024833 26 * @key intermittent 27 * @summary Tests interruption of threads mapping sections of a file channel in 28 * an attempt to deadlock due to nesting of begin calls. 29 */ 30 import java.io.IOException; 31 import java.nio.ByteBuffer; 32 import java.nio.channels.*; 33 import java.nio.channels.FileChannel.MapMode; 34 import java.nio.file.*; 35 import java.util.concurrent.Semaphore; 36 import static java.nio.file.StandardOpenOption.*; 37 38 public class InterruptMapDeadlock { 39 40 static class Mapper extends Thread { 41 final FileChannel fc; 42 final Semaphore gate; 43 volatile Exception exception; 44 Mapper(FileChannel fc, Semaphore gate)45 Mapper(FileChannel fc, Semaphore gate) { 46 this.fc = fc; 47 this.gate = gate; 48 } 49 50 @Override run()51 public void run() { 52 try { 53 gate.acquireUninterruptibly(); 54 fc.map(MapMode.READ_ONLY, 0, 1); 55 throw new Exception("Map succeeded"); 56 } catch (IOException x) { 57 System.out.println(x.getClass() + " (expected)"); 58 } catch (Exception unexpected) { 59 this.exception = unexpected; 60 } 61 } 62 exception()63 Exception exception() { 64 return exception; 65 } 66 startMapper(FileChannel fc, Semaphore gate)67 static Mapper startMapper(FileChannel fc, Semaphore gate) { 68 Mapper r = new Mapper(fc, gate); 69 r.setDaemon(true); 70 r.start(); 71 return r; 72 } 73 } 74 75 static class Interruptor extends Thread { 76 77 final Mapper[] mappers; 78 final Semaphore gate; 79 Interruptor(Mapper[] mappers, Semaphore gate)80 Interruptor(Mapper[] mappers, Semaphore gate) { 81 this.mappers = mappers; 82 this.gate = gate; 83 } 84 run()85 public void run() { 86 gate.release(mappers.length); 87 for (Mapper m : mappers) { 88 m.interrupt(); 89 } 90 } 91 } 92 // the number of mapper threads to start 93 private static final int MAPPER_COUNT = 4; 94 main(String[] args)95 public static void main(String[] args) throws Exception { 96 Path file = Paths.get("data.txt"); 97 FileChannel.open(file, CREATE, TRUNCATE_EXISTING, WRITE).close(); 98 99 Mapper[] mappers = new Mapper[MAPPER_COUNT]; 100 101 for (int i=1; i<=20; i++) { 102 System.out.format("Iteration: %s%n", i); 103 104 FileChannel fc = FileChannel.open(file); 105 boolean failed = false; 106 107 Semaphore gate = new Semaphore(0); 108 // start mapper threads 109 for (int j=0; j<MAPPER_COUNT; j++) { 110 mappers[j] = Mapper.startMapper(fc, gate); 111 } 112 113 // interrupt and wait for the mappers to terminate 114 Interruptor interruptor = new Interruptor(mappers, gate); 115 interruptor.start(); 116 try { 117 interruptor.join(10000); 118 if (interruptor.isAlive()) { 119 System.err.println("Interruptor thread did not terminate:"); 120 Throwable t = new Exception("Stack trace"); 121 t.setStackTrace(interruptor.getStackTrace()); 122 t.printStackTrace(); 123 failed = true; 124 } 125 } catch (InterruptedException x) { 126 System.err.println("Main thread was interrupted"); 127 failed = true; 128 } 129 130 for (Mapper m: mappers) { 131 try { 132 m.join(10000); 133 Exception e = m.exception(); 134 if (e != null) { 135 System.err.println("Mapper thread failed with: " + e); 136 failed = true; 137 } else if (m.isAlive()) { 138 System.err.println("Mapper thread did not terminate:"); 139 Throwable t = new Exception("Stack trace"); 140 t.setStackTrace(m.getStackTrace()); 141 t.printStackTrace(); 142 failed = true; 143 } 144 } catch (InterruptedException x) { 145 System.err.println("Main thread was interrupted"); 146 failed = true; 147 } 148 } 149 150 if (failed) 151 throw new RuntimeException("Test failed - see log for details"); 152 else 153 fc.close(); 154 } 155 } 156 } 157