1 /*
2 * Copyright (c) 2007, 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 /*
25 * @test
26 * @bug 6460501 6236036 6500694 6490770
27 * @summary Repeated failed timed waits shouldn't leak memory
28 * @library /test/lib
29 * @author Martin Buchholz
30 */
31
32 import static java.util.concurrent.TimeUnit.MILLISECONDS;
33 import static java.util.concurrent.TimeUnit.NANOSECONDS;
34
35 import java.io.File;
36 import java.io.FileOutputStream;
37 import java.io.IOException;
38 import java.io.InputStream;
39 import java.io.InputStreamReader;
40 import java.io.OutputStream;
41 import java.io.PrintStream;
42 import java.io.Reader;
43 import java.lang.ref.ReferenceQueue;
44 import java.lang.ref.WeakReference;
45 import java.util.concurrent.BlockingQueue;
46 import java.util.concurrent.Callable;
47 import java.util.concurrent.CountDownLatch;
48 import java.util.concurrent.CyclicBarrier;
49 import java.util.concurrent.ExecutorService;
50 import java.util.concurrent.Executors;
51 import java.util.concurrent.Future;
52 import java.util.concurrent.LinkedBlockingQueue;
53 import java.util.concurrent.Semaphore;
54 import java.util.concurrent.ThreadLocalRandom;
55 import java.util.concurrent.locks.ReentrantLock;
56 import java.util.concurrent.locks.ReentrantReadWriteLock;
57 import java.util.regex.Matcher;
58 import java.util.regex.Pattern;
59 import jdk.test.lib.Utils;
60
61 public class TimedAcquireLeak {
62 static final long LONG_DELAY_MS = Utils.adjustTimeout(10_000);
63
64 static String javahome() {
65 String jh = System.getProperty("java.home");
66 return (jh.endsWith("jre")) ? jh.substring(0, jh.length() - 4) : jh;
67 }
68
69 static final File bin = new File(javahome(), "bin");
70
71 static String javaProgramPath(String programName) {
72 return new File(bin, programName).getPath();
73 }
74
75 static final String java = javaProgramPath("java");
76 static final String jmap = javaProgramPath("jmap");
77 static final String jps = javaProgramPath("jps");
78
79 static String outputOf(Reader r) throws IOException {
80 final StringBuilder sb = new StringBuilder();
81 final char[] buf = new char[1024];
82 int n;
83 while ((n = r.read(buf)) > 0)
84 sb.append(buf, 0, n);
85 return sb.toString();
86 }
87
88 static String outputOf(InputStream is) throws IOException {
89 return outputOf(new InputStreamReader(is, "UTF-8"));
90 }
91
92 static final ExecutorService drainers = Executors.newFixedThreadPool(12);
93 static Future<String> futureOutputOf(final InputStream is) {
94 return drainers.submit(
95 new Callable<String>() { public String call() throws IOException {
96 return outputOf(is); }});}
97
98 static String outputOf(final Process p) {
99 try {
100 Future<String> outputFuture = futureOutputOf(p.getInputStream());
101 Future<String> errorFuture = futureOutputOf(p.getErrorStream());
102 final String output = outputFuture.get();
103 final String error = errorFuture.get();
104 // Check for successful process completion
105 equal(error, "");
106 equal(p.waitFor(), 0);
107 equal(p.exitValue(), 0);
108 return output;
109 } catch (Throwable t) { unexpected(t); throw new Error(t); }
110 }
111
112 static String commandOutputOf(String... cmd) {
113 try { return outputOf(new ProcessBuilder(cmd).start()); }
114 catch (Throwable t) { unexpected(t); throw new Error(t); }
115 }
116
117 // To be called exactly twice by the parent process
118 static <T> T rendezvousParent(Process p,
119 Callable<T> callable) throws Throwable {
120 p.getInputStream().read();
121 T result = callable.call();
122 sendByte(p.getOutputStream());
123 return result;
124 }
125
126 /** No guarantees, but effective in practice. */
127 private static void forceFullGc() {
128 long timeoutMillis = 1000L;
129 CountDownLatch finalized = new CountDownLatch(1);
130 ReferenceQueue<Object> queue = new ReferenceQueue<>();
131 WeakReference<Object> ref = new WeakReference<>(
132 new Object() { protected void finalize() { finalized.countDown(); }},
133 queue);
134 try {
135 for (int tries = 3; tries--> 0; ) {
136 System.gc();
137 if (finalized.await(timeoutMillis, MILLISECONDS)
138 && queue.remove(timeoutMillis) != null
139 && ref.get() == null) {
140 System.runFinalization(); // try to pick up stragglers
141 return;
142 }
143 timeoutMillis *= 4;
144 }
145 } catch (InterruptedException unexpected) {
146 throw new AssertionError("unexpected InterruptedException");
147 }
148 throw new AssertionError("failed to do a \"full\" gc");
149 }
150
151 // To be called exactly twice by the child process
152 public static void rendezvousChild() {
153 try {
154 forceFullGc();
155 sendByte(System.out);
156 System.in.read();
157 } catch (Throwable t) { throw new Error(t); }
158 }
159
160 static String match(String s, String regex, int group) {
161 Matcher matcher = Pattern.compile(regex).matcher(s);
162 matcher.find();
163 return matcher.group(group);
164 }
165
166 /** It's all about sending a message! */
167 static void sendByte(OutputStream s) throws IOException {
168 s.write('!');
169 s.flush();
170 }
171
172 static int objectsInUse(final Process child,
173 final String childPid,
174 final String className) {
175 final String regex =
176 "(?m)^ *[0-9]+: +([0-9]+) +[0-9]+ +\\Q"+className+"\\E(?:$| )";
177 final Callable<Integer> objectsInUse =
178 new Callable<Integer>() { public Integer call() {
179 Integer i = Integer.parseInt(
180 match(commandOutputOf(jmap, "-histo:live", childPid),
181 regex, 1));
182 if (i > 100)
183 System.out.print(
184 commandOutputOf(jmap,
185 "-dump:file=dump,format=b",
186 childPid));
187 return i;
188 }};
189 try { return rendezvousParent(child, objectsInUse); }
190 catch (Throwable t) { unexpected(t); return -1; }
191 }
192
193 static void realMain(String[] args) throws Throwable {
194 // jmap doesn't work on Windows
195 if (System.getProperty("os.name").startsWith("Windows"))
196 return;
197
198 final String childClassName = Job.class.getName();
199 final String classToCheckForLeaks = Job.classToCheckForLeaks();
200 final String uniqueID =
201 String.valueOf(ThreadLocalRandom.current().nextInt(Integer.MAX_VALUE));
202
203 final String[] jobCmd = {
204 java, "-Xmx8m", "-XX:+UsePerfData",
205 "-classpath", System.getProperty("test.class.path"),
206 childClassName, uniqueID
207 };
208 final Process p = new ProcessBuilder(jobCmd).start();
209 // Ensure subprocess jvm has started, so that jps can find it
210 p.getInputStream().read();
211 sendByte(p.getOutputStream());
212
213 final String childPid =
214 match(commandOutputOf(jps, "-m"),
215 "(?m)^ *([0-9]+) +\\Q"+childClassName+"\\E *"+uniqueID+"$", 1);
216
217 final int n0 = objectsInUse(p, childPid, classToCheckForLeaks);
218 final int n1 = objectsInUse(p, childPid, classToCheckForLeaks);
219 equal(p.waitFor(), 0);
220 equal(p.exitValue(), 0);
221 failed += p.exitValue();
222
223 // Check that no objects were leaked.
224 //
225 // TODO: This test is very brittle, depending on current JDK
226 // implementation, and needing occasional adjustment.
227 System.out.printf("%d -> %d%n", n0, n1);
228 // Almost always n0 == n1
229 // Maximum jitter observed in practice is 10 -> 17
230 check(Math.abs(n1 - n0) < 10);
231 check(n1 < 25);
232 drainers.shutdown();
233 if (!drainers.awaitTermination(LONG_DELAY_MS, MILLISECONDS)) {
234 drainers.shutdownNow(); // last resort
235 throw new AssertionError("thread pool did not terminate");
236 }
237 }
238
239 //----------------------------------------------------------------
240 // The main class of the child process.
241 // Job's job is to:
242 // - provide the name of a class to check for leaks.
243 // - call rendezvousChild exactly twice, while quiescent.
244 // - in between calls to rendezvousChild, run code that may leak.
245 //----------------------------------------------------------------
246 public static class Job {
247 static String classToCheckForLeaks() {
248 return
249 "java.util.concurrent.locks.AbstractQueuedSynchronizer$Node";
250 }
251
252 public static void main(String[] args) throws Throwable {
253 // Synchronize with parent process, so that jps can find us
254 sendByte(System.out);
255 System.in.read();
256
257 final ReentrantLock lock = new ReentrantLock();
258 lock.lock();
259
260 final ReentrantReadWriteLock rwlock
261 = new ReentrantReadWriteLock();
262 final ReentrantReadWriteLock.ReadLock readLock
263 = rwlock.readLock();
264 final ReentrantReadWriteLock.WriteLock writeLock
265 = rwlock.writeLock();
266 rwlock.writeLock().lock();
267
268 final BlockingQueue<Object> q = new LinkedBlockingQueue<>();
269 final Semaphore fairSem = new Semaphore(0, true);
270 final Semaphore unfairSem = new Semaphore(0, false);
271 //final int threads =
272 //rnd.nextInt(Runtime.getRuntime().availableProcessors() + 1) + 1;
273 final int threads = 3;
274 // On Linux, this test runs very slowly for some reason,
275 // so use a smaller number of iterations.
276 // Solaris can handle 1 << 18.
277 // On the other hand, jmap is much slower on Solaris...
278 final int iterations = 1 << 8;
279 final CyclicBarrier cb = new CyclicBarrier(threads+1);
280
281 for (int i = 0; i < threads; i++)
282 new Thread() { public void run() {
283 try {
284 final ThreadLocalRandom rnd = ThreadLocalRandom.current();
285 for (int j = 0; j < iterations; j++) {
286 if (j == iterations/10 || j == iterations - 1) {
287 cb.await(); // Quiesce
288 cb.await(); // Resume
289 }
290 //int t = rnd.nextInt(2000);
291 int t = rnd.nextInt(900);
292 check(! lock.tryLock(t, NANOSECONDS));
293 check(! readLock.tryLock(t, NANOSECONDS));
294 check(! writeLock.tryLock(t, NANOSECONDS));
295 equal(null, q.poll(t, NANOSECONDS));
296 check(! fairSem.tryAcquire(t, NANOSECONDS));
297 check(! unfairSem.tryAcquire(t, NANOSECONDS));
298 }
299 } catch (Throwable t) { unexpected(t); }
300 }}.start();
301
302 cb.await(); // Quiesce
303 rendezvousChild(); // Measure
304 cb.await(); // Resume
305
306 cb.await(); // Quiesce
307 rendezvousChild(); // Measure
308 cb.await(); // Resume
309
310 System.exit(failed);
311 }
312
313 // If something goes wrong, we might never see it, since IO
314 // streams are connected to the parent. So we need a special
315 // purpose print method to debug Jobs.
316 static void debugPrintf(String format, Object... args) {
317 try {
318 new PrintStream(new FileOutputStream("/dev/tty"))
319 .printf(format, args);
320 } catch (Throwable t) { throw new Error(t); }
321 }
322 }
323
324 //--------------------- Infrastructure ---------------------------
325 static volatile int passed = 0, failed = 0;
326 static void pass() {passed++;}
327 static void fail() {failed++; Thread.dumpStack();}
328 static void fail(String msg) {System.out.println(msg); fail();}
329 static void unexpected(Throwable t) {failed++; t.printStackTrace();}
330 static void check(boolean cond) {if (cond) pass(); else fail();}
331 static void check(boolean cond, String m) {if (cond) pass(); else fail(m);}
332 static void equal(Object x, Object y) {
333 if (x == null ? y == null : x.equals(y)) pass();
334 else fail(x + " not equal to " + y);}
335 public static void main(String[] args) throws Throwable {
336 try {realMain(args);} catch (Throwable t) {unexpected(t);}
337 System.out.printf("%nPassed = %d, failed = %d%n%n", passed, failed);
338 if (failed > 0) throw new AssertionError("Some tests failed");}
339 }