1 /*
2 * Copyright (c) 2021, 2023, 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 * @summary Basic test for JFR jdk.VirtualThreadXXX events
27 * @requires vm.continuations
28 * @modules jdk.jfr java.base/java.lang:+open
29 * @library /test/lib
30 * @run junit/othervm --enable-native-access=ALL-UNNAMED JfrEvents
31 */
32
33 import java.io.IOException;
34 import java.nio.file.Path;
35 import java.util.List;
36 import java.util.Map;
37 import java.util.concurrent.Executor;
38 import java.util.concurrent.ExecutorService;
39 import java.util.concurrent.Executors;
40 import java.util.concurrent.RejectedExecutionException;
41 import java.util.concurrent.ThreadFactory;
42 import java.util.concurrent.atomic.AtomicBoolean;
43 import java.util.concurrent.atomic.AtomicReference;
44 import java.util.concurrent.locks.LockSupport;
45 import java.util.function.Consumer;
46 import java.util.stream.Collectors;
47 import java.util.stream.Stream;
48
49 import jdk.jfr.EventType;
50 import jdk.jfr.Recording;
51 import jdk.jfr.consumer.RecordedEvent;
52 import jdk.jfr.consumer.RecordingFile;
53
54 import jdk.test.lib.thread.VThreadPinner;
55 import jdk.test.lib.thread.VThreadRunner.ThrowingRunnable;
56 import org.junit.jupiter.api.Test;
57 import org.junit.jupiter.params.ParameterizedTest;
58 import org.junit.jupiter.params.provider.Arguments;
59 import org.junit.jupiter.params.provider.MethodSource;
60 import static org.junit.jupiter.api.Assertions.*;
61
62 class JfrEvents {
63
64 /**
65 * Test jdk.VirtualThreadStart and jdk.VirtualThreadEnd events.
66 */
67 @Test
68 void testVirtualThreadStartAndEnd() throws Exception {
69 try (Recording recording = new Recording()) {
70 recording.enable("jdk.VirtualThreadStart");
71 recording.enable("jdk.VirtualThreadEnd");
72
73 // execute 100 tasks, each in their own virtual thread
74 recording.start();
75 ThreadFactory factory = Thread.ofVirtual().factory();
76 try (var executor = Executors.newThreadPerTaskExecutor(factory)) {
77 for (int i = 0; i < 100; i++) {
78 executor.submit(() -> { });
79 }
80 Thread.sleep(1000); // give time for thread end events to be recorded
81 } finally {
82 recording.stop();
83 }
84
85 Map<String, Integer> events = sumEvents(recording);
86 System.err.println(events);
87
88 int startCount = events.getOrDefault("jdk.VirtualThreadStart", 0);
89 int endCount = events.getOrDefault("jdk.VirtualThreadEnd", 0);
90 assertEquals(100, startCount);
91 assertEquals(100, endCount);
92 }
93 }
94
95 /**
96 * Arguments for testVirtualThreadPinned to test jdk.VirtualThreadPinned event.
97 * [0] label/description
98 * [1] the operation to park/wait
99 * [2] the Thread.State when parked/waiting
100 * [3] the action to unpark/notify the thread
101 */
102 static Stream<Arguments> pinnedCases() {
103 Object lock = new Object();
104
105 // park with native frame on stack
106 var finish1 = new AtomicBoolean();
107 var parkWhenPinned = Arguments.of(
108 "LockSupport.park when pinned",
109 (ThrowingRunnable<Exception>) () -> {
110 VThreadPinner.runPinned(() -> {
111 while (!finish1.get()) {
112 LockSupport.park();
113 }
114 });
115 },
116 Thread.State.WAITING,
117 (Consumer<Thread>) t -> {
118 finish1.set(true);
119 LockSupport.unpark(t);
120 }
121 );
122
123 // timed park with native frame on stack
124 var finish2 = new AtomicBoolean();
125 var timedParkWhenPinned = Arguments.of(
126 "LockSupport.parkNanos when pinned",
127 (ThrowingRunnable<Exception>) () -> {
128 VThreadPinner.runPinned(() -> {
129 while (!finish2.get()) {
130 LockSupport.parkNanos(Long.MAX_VALUE);
131 }
132 });
133 },
134 Thread.State.TIMED_WAITING,
135 (Consumer<Thread>) t -> {
136 finish2.set(true);
137 LockSupport.unpark(t);
138 }
139 );
140
141 // block on monitorenter with native frame on stack
142 var blockWhenPinned = Arguments.of(
143 "Contended monitorenter when pinned",
144 (ThrowingRunnable<Exception>) () -> {
145 var readyToEnter = new AtomicBoolean();
146 var thread = Thread.ofVirtual().unstarted(() -> {
147 VThreadPinner.runPinned(() -> {
148 readyToEnter.set(true);
149 synchronized (lock) { }
150 });
151 });
152 try {
153 synchronized (lock) {
154 thread.start();
155 while (!readyToEnter.get()) {
156 Thread.sleep(10);
157 }
158 await(thread, Thread.State.BLOCKED);
159 }
160 } finally {
161 thread.join();
162 }
163 },
164 Thread.State.TERMINATED,
165 (Consumer<Thread>) t -> { }
166 );
167
168 // untimed Object.wait
169 var waitWhenPinned = Arguments.of(
170 "Object.wait",
171 (ThrowingRunnable<Exception>) () -> {
172 synchronized (lock) {
173 lock.wait();
174 }
175 },
176 Thread.State.WAITING,
177 (Consumer<Thread>) t -> {
178 synchronized (lock) {
179 lock.notifyAll();
180 }
181 }
182 );
183
184 // timed Object.wait
185 var timedWaitWhenPinned = Arguments.of(
186 "Object.wait(millis)",
187 (ThrowingRunnable<Exception>) () -> {
188 synchronized (lock) {
189 lock.wait(Long.MAX_VALUE);
190 }
191 },
192 Thread.State.TIMED_WAITING,
193 (Consumer<Thread>) t -> {
194 synchronized (lock) {
195 lock.notifyAll();
196 }
197 }
198 );
199
200 return Stream.of(parkWhenPinned,
201 timedParkWhenPinned,
202 blockWhenPinned,
203 waitWhenPinned,
204 timedWaitWhenPinned);
205 }
206
207 /**
208 * Test jdk.VirtualThreadPinned event.
209 */
210 @ParameterizedTest
211 @MethodSource("pinnedCases")
212 void testVirtualThreadPinned(String label,
213 ThrowingRunnable<Exception> parker,
214 Thread.State expectedState,
215 Consumer<Thread> unparker) throws Exception {
216
217 try (Recording recording = new Recording()) {
218 recording.enable("jdk.VirtualThreadPinned");
219
220 recording.start();
221 try {
222 var exception = new AtomicReference<Throwable>();
223 var thread = Thread.ofVirtual().start(() -> {
224 try {
225 parker.run();
226 } catch (Throwable e) {
227 exception.set(e);
228 }
229 });
230 try {
231 // wait for thread to park/wait
232 await(thread, expectedState);
233 } finally {
234 unparker.accept(thread);
235 thread.join();
236 assertNull(exception.get());
237 }
238 } finally {
239 recording.stop();
240 }
241
242 Map<String, Integer> events = sumEvents(recording);
243 System.err.println(events);
244
245 // should have at least one pinned event
246 int pinnedCount = events.getOrDefault("jdk.VirtualThreadPinned", 0);
247 assertTrue(pinnedCount >= 1, "Expected one or more events");
248 }
249 }
250
251 /**
252 * Test jdk.VirtualThreadSubmitFailed event.
253 */
254 @Test
255 void testVirtualThreadSubmitFailed() throws Exception {
256 try (Recording recording = new Recording()) {
257 recording.enable("jdk.VirtualThreadSubmitFailed");
258
259 recording.start();
260 try (ExecutorService pool = Executors.newCachedThreadPool()) {
261 Executor scheduler = task -> pool.execute(task);
262
263 // create virtual thread that uses custom scheduler
264 ThreadFactory factory = ThreadBuilders.virtualThreadBuilder(scheduler).factory();
265
266 // start a thread
267 Thread thread = factory.newThread(LockSupport::park);
268 thread.start();
269
270 // wait for thread to park
271 await(thread, Thread.State.WAITING);
272
273 // shutdown scheduler
274 pool.shutdown();
275
276 // unpark, the submit should fail
277 try {
278 LockSupport.unpark(thread);
279 fail();
280 } catch (RejectedExecutionException expected) { }
281
282 // start another thread, it should fail and an event should be recorded
283 try {
284 factory.newThread(LockSupport::park).start();
285 throw new RuntimeException("RejectedExecutionException expected");
286 } catch (RejectedExecutionException expected) { }
287 } finally {
288 recording.stop();
289 }
290
291 Map<String, Integer> events = sumEvents(recording);
292 System.err.println(events);
293
294 int count = events.getOrDefault("jdk.VirtualThreadSubmitFailed", 0);
295 assertEquals(2, count);
296 }
297 }
298
299 /**
300 * Read the events from the recording and return a map of event name to count.
301 */
302 private static Map<String, Integer> sumEvents(Recording recording) throws IOException {
303 Path recordingFile = recordingFile(recording);
304 List<RecordedEvent> events = RecordingFile.readAllEvents(recordingFile);
305 return events.stream()
306 .map(RecordedEvent::getEventType)
307 .collect(Collectors.groupingBy(EventType::getName,
308 Collectors.summingInt(x -> 1)));
309 }
310
311 /**
312 * Return the file path to the recording file.
313 */
314 private static Path recordingFile(Recording recording) throws IOException {
315 Path recordingFile = recording.getDestination();
316 if (recordingFile == null) {
317 ProcessHandle h = ProcessHandle.current();
318 recordingFile = Path.of("recording-" + recording.getId() + "-pid" + h.pid() + ".jfr");
319 recording.dump(recordingFile);
320 }
321 return recordingFile;
322 }
323
324 /**
325 * Waits for the given thread to reach a given state.
326 */
327 private static void await(Thread thread, Thread.State expectedState) throws InterruptedException {
328 Thread.State state = thread.getState();
329 while (state != expectedState) {
330 Thread.sleep(10);
331 state = thread.getState();
332 }
333 }
334 }