1 /* 2 * Copyright (c) 2005, 2008, 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 6207928 6328220 6378321 6625723 27 * @summary Recursive lock invariant sanity checks 28 * @library /test/lib 29 * @author Martin Buchholz 30 */ 31 32 import static java.util.concurrent.TimeUnit.MILLISECONDS; 33 34 import java.io.ByteArrayInputStream; 35 import java.io.ByteArrayOutputStream; 36 import java.io.IOException; 37 import java.io.InputStream; 38 import java.io.ObjectInputStream; 39 import java.io.ObjectOutputStream; 40 import java.util.Random; 41 import java.util.concurrent.CyclicBarrier; 42 import java.util.concurrent.ExecutorService; 43 import java.util.concurrent.Executors; 44 import java.util.concurrent.TimeUnit; 45 import java.util.concurrent.locks.Lock; 46 import java.util.concurrent.locks.ReentrantLock; 47 import java.util.concurrent.locks.ReentrantReadWriteLock; 48 import jdk.test.lib.Utils; 49 50 // I am the Cownt, and I lahve to cownt. 51 public class Count { 52 static final long LONG_DELAY_MS = Utils.adjustTimeout(10_000); 53 final Random rnd = new Random(); 54 55 void lock(Lock lock) { 56 try { 57 switch (rnd.nextInt(4)) { 58 case 0: lock.lock(); break; 59 case 1: lock.lockInterruptibly(); break; 60 case 2: check(lock.tryLock()); break; 61 case 3: check(lock.tryLock(45, TimeUnit.MINUTES)); break; 62 } 63 } catch (Throwable t) { unexpected(t); } 64 } 65 66 void test(String[] args) throws Throwable { 67 for (boolean fair : new boolean[] { true, false }) 68 for (boolean serialClone : new boolean[] { true, false }) { 69 testReentrantLocks(fair, serialClone); 70 testConcurrentReadLocks(fair, serialClone); 71 } 72 } 73 74 void testConcurrentReadLocks(final boolean fair, 75 final boolean serialClone) throws Throwable { 76 final int nThreads = 10; 77 final CyclicBarrier barrier = new CyclicBarrier(nThreads); 78 final ExecutorService es = Executors.newFixedThreadPool(nThreads); 79 final ReentrantReadWriteLock rwl = serialClone ? 80 serialClone(new ReentrantReadWriteLock(fair)) : 81 new ReentrantReadWriteLock(fair); 82 for (int i = 0; i < nThreads; i++) { 83 es.submit(new Runnable() { public void run() { 84 try { 85 int n = 5; 86 for (int i = 0; i < n; i++) { 87 barrier.await(); 88 equal(rwl.getReadHoldCount(), i); 89 equal(rwl.getWriteHoldCount(), 0); 90 check(! rwl.isWriteLocked()); 91 equal(rwl.getReadLockCount(), nThreads * i); 92 barrier.await(); 93 lock(rwl.readLock()); 94 } 95 for (int i = 0; i < n; i++) { 96 rwl.readLock().unlock(); 97 barrier.await(); 98 equal(rwl.getReadHoldCount(), n-i-1); 99 equal(rwl.getReadLockCount(), nThreads*(n-i-1)); 100 equal(rwl.getWriteHoldCount(), 0); 101 check(! rwl.isWriteLocked()); 102 barrier.await(); 103 } 104 THROWS(IllegalMonitorStateException.class, 105 new F(){void f(){rwl.readLock().unlock();}}, 106 new F(){void f(){rwl.writeLock().unlock();}}); 107 barrier.await(); 108 } catch (Throwable t) { unexpected(t); }}});} 109 es.shutdown(); 110 check(es.awaitTermination(LONG_DELAY_MS, MILLISECONDS)); 111 } 112 113 void testReentrantLocks(final boolean fair, 114 final boolean serialClone) throws Throwable { 115 final ReentrantLock rl = serialClone ? 116 serialClone(new ReentrantLock(fair)) : 117 new ReentrantLock(fair); 118 final ReentrantReadWriteLock rwl = serialClone ? 119 serialClone(new ReentrantReadWriteLock(fair)) : 120 new ReentrantReadWriteLock(fair); 121 final int depth = 10; 122 equal(rl.isFair(), fair); 123 equal(rwl.isFair(), fair); 124 check(! rl.isLocked()); 125 check(! rwl.isWriteLocked()); 126 check(! rl.isHeldByCurrentThread()); 127 check(! rwl.isWriteLockedByCurrentThread()); 128 check(! rwl.writeLock().isHeldByCurrentThread()); 129 130 for (int i = 0; i < depth; i++) { 131 equal(rl.getHoldCount(), i); 132 equal(rwl.getReadLockCount(), i); 133 equal(rwl.getReadHoldCount(), i); 134 equal(rwl.getWriteHoldCount(), i); 135 equal(rwl.writeLock().getHoldCount(), i); 136 equal(rl.isLocked(), i > 0); 137 equal(rwl.isWriteLocked(), i > 0); 138 lock(rl); 139 lock(rwl.writeLock()); 140 lock(rwl.readLock()); 141 } 142 143 for (int i = depth; i > 0; i--) { 144 check(! rl.hasQueuedThreads()); 145 check(! rwl.hasQueuedThreads()); 146 check(! rl.hasQueuedThread(Thread.currentThread())); 147 check(! rwl.hasQueuedThread(Thread.currentThread())); 148 check(rl.isLocked()); 149 check(rwl.isWriteLocked()); 150 check(rl.isHeldByCurrentThread()); 151 check(rwl.isWriteLockedByCurrentThread()); 152 check(rwl.writeLock().isHeldByCurrentThread()); 153 equal(rl.getQueueLength(), 0); 154 equal(rwl.getQueueLength(), 0); 155 equal(rwl.getReadLockCount(), i); 156 equal(rl.getHoldCount(), i); 157 equal(rwl.getReadHoldCount(), i); 158 equal(rwl.getWriteHoldCount(), i); 159 equal(rwl.writeLock().getHoldCount(), i); 160 rwl.readLock().unlock(); 161 rwl.writeLock().unlock(); 162 rl.unlock(); 163 } 164 THROWS(IllegalMonitorStateException.class, 165 new F(){void f(){rl.unlock();}}, 166 new F(){void f(){rwl.readLock().unlock();}}, 167 new F(){void f(){rwl.writeLock().unlock();}}); 168 } 169 170 //--------------------- Infrastructure --------------------------- 171 volatile int passed = 0, failed = 0; 172 void pass() {passed++;} 173 void fail() {failed++; Thread.dumpStack();} 174 void fail(String msg) {System.err.println(msg); fail();} 175 void unexpected(Throwable t) {failed++; t.printStackTrace();} 176 void check(boolean cond) {if (cond) pass(); else fail();} 177 void equal(Object x, Object y) { 178 if (x == null ? y == null : x.equals(y)) pass(); 179 else fail(x + " not equal to " + y);} 180 public static void main(String[] args) throws Throwable { 181 new Count().instanceMain(args);} 182 void instanceMain(String[] args) throws Throwable { 183 try {test(args);} catch (Throwable t) {unexpected(t);} 184 System.out.printf("%nPassed = %d, failed = %d%n%n", passed, failed); 185 if (failed > 0) throw new AssertionError("Some tests failed");} 186 abstract class F {abstract void f() throws Throwable;} 187 void THROWS(Class<? extends Throwable> k, F... fs) { 188 for (F f : fs) 189 try {f.f(); fail("Expected " + k.getName() + " not thrown");} 190 catch (Throwable t) { 191 if (k.isAssignableFrom(t.getClass())) pass(); 192 else unexpected(t);}} 193 194 static byte[] serializedForm(Object obj) { 195 try { 196 ByteArrayOutputStream baos = new ByteArrayOutputStream(); 197 new ObjectOutputStream(baos).writeObject(obj); 198 return baos.toByteArray(); 199 } catch (IOException e) { throw new RuntimeException(e); }} 200 static Object readObject(byte[] bytes) 201 throws IOException, ClassNotFoundException { 202 InputStream is = new ByteArrayInputStream(bytes); 203 return new ObjectInputStream(is).readObject();} 204 @SuppressWarnings("unchecked") 205 static <T> T serialClone(T obj) { 206 try { return (T) readObject(serializedForm(obj)); } 207 catch (Exception e) { throw new RuntimeException(e); }} 208 }