1 /*
2 * Copyright (c) 2013, 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 8022595
27 * @summary JSR292: deadlock during class loading of MethodHandles, MethodHandleImpl & MethodHandleNatives
28 *
29 * @run main/othervm ConcurrentClassLoadingTest
30 */
31 import java.util.*;
32 import java.util.concurrent.BrokenBarrierException;
33 import java.util.concurrent.CyclicBarrier;
34
35 public class ConcurrentClassLoadingTest {
36 int numThreads = 0;
37 long seed = 0;
38 CyclicBarrier l;
39 Random rand;
40
41 public static void main(String[] args) throws Throwable {
42 ConcurrentClassLoadingTest test = new ConcurrentClassLoadingTest();
43 test.parseArgs(args);
44 test.run();
45 }
46
47 void parseArgs(String[] args) {
48 int i = 0;
49 while (i < args.length) {
50 String flag = args[i];
51 switch(flag) {
52 case "-seed":
53 seed = Long.parseLong(args[++i]);
54 break;
55 case "-numThreads":
56 numThreads = Integer.parseInt(args[++i]);
57 break;
58 default:
59 throw new Error("Unknown flag: " + flag);
60 }
61 ++i;
62 }
63 }
64
65 void init() {
66 if (numThreads == 0) {
67 numThreads = Runtime.getRuntime().availableProcessors();
68 }
69
70 if (seed == 0) {
71 seed = (new Random()).nextLong();
72 }
73 rand = new Random(seed);
74
75 l = new CyclicBarrier(numThreads + 1);
76
77 System.out.printf("Threads: %d\n", numThreads);
78 System.out.printf("Seed: %d\n", seed);
79 }
80
81 final List<Loader> loaders = new ArrayList<>();
82
83 void prepare() {
84 List<String> c = new ArrayList<>(Arrays.asList(classNames));
85
86 // Split classes between loading threads
87 int count = (classNames.length / numThreads) + 1;
88 for (int t = 0; t < numThreads; t++) {
89 List<String> sel = new ArrayList<>();
90
91 System.out.printf("Thread #%d:\n", t);
92 for (int i = 0; i < count; i++) {
93 if (c.size() == 0) break;
94
95 int k = rand.nextInt(c.size());
96 String elem = c.remove(k);
97 sel.add(elem);
98 System.out.printf("\t%s\n", elem);
99 }
100 loaders.add(new Loader(sel));
101 }
102
103 // Print diagnostic info when the test hangs
104 Runtime.getRuntime().addShutdownHook(new Thread() {
105 public void run() {
106 boolean alive = false;
107 for (Loader l : loaders) {
108 if (!l.isAlive()) continue;
109
110 if (!alive) {
111 System.out.println("Some threads are still alive:");
112 alive = true;
113 }
114
115 System.out.println(l.getName());
116 for (StackTraceElement elem : l.getStackTrace()) {
117 System.out.println("\t"+elem.toString());
118 }
119 }
120 }
121 });
122 }
123
124 public void run() throws Throwable {
125 init();
126 prepare();
127
128 for (Loader loader : loaders) {
129 loader.start();
130 }
131
132 l.await();
133
134 for (Loader loader : loaders) {
135 loader.join();
136 }
137 }
138
139 class Loader extends Thread {
140 List<String> classes;
141
142 public Loader(List<String> classes) {
143 this.classes = classes;
144 setDaemon(true);
145 }
146
147 @Override
148 public void run() {
149 try {
150 l.await();
151
152 for (String name : classes) {
153 Class.forName(name).getName();
154 }
155 } catch (ClassNotFoundException | BrokenBarrierException | InterruptedException e) {
156 throw new Error(e);
157 }
158 }
159 }
160
161 final static String[] classNames = {
162 "java.lang.invoke.CallSite",
163 "java.lang.invoke.ConstantCallSite",
164 "java.lang.invoke.LambdaConversionException",
165 "java.lang.invoke.LambdaMetafactory",
166 "java.lang.invoke.MethodHandle",
167 "java.lang.invoke.MethodHandleInfo",
168 "java.lang.invoke.MethodHandleProxies",
169 "java.lang.invoke.MethodHandles",
170 "java.lang.invoke.MethodType",
171 "java.lang.invoke.MutableCallSite",
172 "java.lang.invoke.SerializedLambda",
173 "java.lang.invoke.SwitchPoint",
174 "java.lang.invoke.VolatileCallSite",
175 "java.lang.invoke.WrongMethodTypeException"
176 };
177 }