1 /*
2 * Copyright (c) 2017, 2018, 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. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package jdk.jfr.internal;
27
28 import java.io.IOException;
29 import java.util.List;
30
31 import jdk.jfr.Event;
32
33 /**
34 * Interface against the JVM.
35 *
36 */
37 public final class JVM {
38 private static final JVM jvm = new JVM();
39
40 // JVM signals file changes by doing Object#notifu on this object
41 static final Object FILE_DELTA_CHANGE = new Object();
42
43 static final long RESERVED_CLASS_ID_LIMIT = 400;
44
45 private volatile boolean recording;
46 private volatile boolean nativeOK;
47
48 private static native void registerNatives();
49
50 static {
51 registerNatives();
52 // XXX
53 // for (LogTag tag : LogTag.values()) {
54 // subscribeLogLevel(tag, tag.id);
55 // }
56 Options.ensureInitialized();
57 EventHandlerProxyCreator.ensureInitialized();
58 }
59
60 /**
61 * Get the one and only JVM.
62 *
63 * @return the JVM
64 */
65 public static JVM getJVM() {
66 return jvm;
67 }
68
69 private JVM() {
70 }
71
72 /**
73 * Begin recording events
74 *
75 * Requires that JFR has been started with {@link #createNativeJFR()}
76 */
77 public native void beginRecording();
78
79 /**
80 * Return ticks
81 *
82 * @return the time, in ticks
83 *
84 */
85 // @HotSpotIntrinsicCandidate
86 public static native long counterTime();
87
88
89 /**
90 * Emits native periodic event.
91 *
92 * @param eventTypeId type id
93 *
94 * @param timestamp commit time for event
95 * @param when when it is being done {@link Periodic.When}
96 *
97 * @return true if the event was committed
98 */
99 public native boolean emitEvent(long eventTypeId, long timestamp, long when);
100
101 /**
102 * End recording events, which includes flushing data in thread buffers
103 *
104 * Requires that JFR has been started with {@link #createNativeJFR()}
105 *
106 */
107 public native void endRecording();
108
109 /**
110 * Return a list of all classes deriving from {@link Event}
111 *
112 * @return list of event classes.
113 */
114 public native List<Class<? extends Event>> getAllEventClasses();
115
116 /**
117 * Return a count of the number of unloaded classes deriving from {@link Event}
118 *
119 * @return number of unloaded event classes.
120 */
121 public native long getUnloadedEventClassCount();
122
123 /**
124 * Return a unique identifier for a class. The class is marked as being
125 * "in use" in JFR.
126 *
127 * @param clazz clazz
128 *
129 * @return a unique class identifier
130 */
131 // @HotSpotIntrinsicCandidate
132 public static native long getClassId(Class<?> clazz);
133
134 // temporary workaround until we solve intrinsics supporting epoch shift tagging
135 public static native long getClassIdNonIntrinsic(Class<?> clazz);
136
137 /**
138 * Return process identifier.
139 *
140 * @return process identifier
141 */
142 public native String getPid();
143
144 /**
145 * Return unique identifier for stack trace.
146 *
147 * Requires that JFR has been started with {@link #createNativeJFR()}
148 *
149 * @param skipCount number of frames to skip
150 * @return a unique stack trace identifier
151 */
152 public native long getStackTraceId(int skipCount);
153
154 /**
155 * Return identifier for thread
156 *
157 * @param t thread
158 * @return a unique thread identifier
159 */
160 public native long getThreadId(Thread t);
161
162 /**
163 * Frequency, ticks per second
164 *
165 * @return frequency
166 */
167 public native long getTicksFrequency();
168
169 /**
170 * Write message to log. Should swallow null or empty message, and be able
171 * to handle any Java character and not crash with very large message
172 *
173 * @param tagSetId the tagset id
174 * @param level on level
175 * @param message log message
176 *
177 */
178 public static native void log(int tagSetId, int level, String message);
179
180 /**
181 * Subscribe to LogLevel updates for LogTag
182 *
183 * @param lt the log tag to subscribe
184 * @param tagSetId the tagset id
185 */
186 public static native void subscribeLogLevel(LogTag lt, int tagSetId);
187
188 /**
189 * Call to invoke event tagging and retransformation of the passed classes
190 *
191 * @param classes
192 */
193 public native synchronized void retransformClasses(Class<?>[] classes);
194
195 /**
196 * Enable event
197 *
198 * @param eventTypeId event type id
199 *
200 * @param enabled enable event
201 */
202 public native void setEnabled(long eventTypeId, boolean enabled);
203
204 /**
205 * Interval at which the JVM should notify on {@link #FILE_DELTA_CHANGE}
206 *
207 * @param delta number of bytes, reset after file rotation
208 */
209 public native void setFileNotification(long delta);
210
211 /**
212 * Set the number of global buffers to use
213 *
214 * @param count
215 *
216 * @throws IllegalArgumentException if count is not within a valid range
217 * @throws IllegalStateException if value can't be changed
218 */
219 public native void setGlobalBufferCount(long count) throws IllegalArgumentException, IllegalStateException;
220
221 /**
222 * Set size of a global buffer
223 *
224 * @param size
225 *
226 * @throws IllegalArgumentException if buffer size is not within a valid
227 * range
228 */
229 public native void setGlobalBufferSize(long size) throws IllegalArgumentException;
230
231 /**
232 * Set overall memory size
233 *
234 * @param size
235 *
236 * @throws IllegalArgumentException if memory size is not within a valid
237 * range
238 */
239 public native void setMemorySize(long size) throws IllegalArgumentException;
240
241 /**
242
243 /**
244 * Set interval for method samples, in milliseconds.
245 *
246 * Setting interval to 0 turns off the method sampler.
247 *
248 * @param intervalMillis the sampling interval
249 */
250 public native void setMethodSamplingInterval(long type, long intervalMillis);
251
252 /**
253 * Sets the file where data should be written.
254 *
255 * Requires that JFR has been started with {@link #createNativeJFR()}
256 *
257 * <pre>
258 * Recording Previous Current Action
259 * ==============================================
260 * true null null Ignore, keep recording in-memory
261 * true null file1 Start disk recording
262 * true file null Copy out metadata to disk and continue in-memory recording
263 * true file1 file2 Copy out metadata and start with new File (file2)
264 * false * null Ignore, but start recording to memory with {@link #beginRecording()}
265 * false * file Ignore, but start recording to disk with {@link #beginRecording()}
266 *
267 * </pre>
268 *
269 * recording can be set to true/false with {@link #beginRecording()}
270 * {@link #endRecording()}
271 *
272 * @param file the file where data should be written, or null if it should
273 * not be copied out (in memory).
274 *
275 * @throws IOException
276 */
277 public native void setOutput(String file);
278
279 /**
280 * Controls if a class deriving from jdk.jfr.Event should
281 * always be instrumented on class load.
282 *
283 * @param force, true to force initialization, false otherwise
284 */
285 public native void setForceInstrumentation(boolean force);
286
287 /**
288 * Turn on/off thread sampling.
289 *
290 * @param sampleThreads true if threads should be sampled, false otherwise.
291 *
292 * @throws IllegalStateException if state can't be changed.
293 */
294 public native void setSampleThreads(boolean sampleThreads) throws IllegalStateException;
295
296 /**
297 * Turn on/off compressed integers.
298 *
299 * @param compressed true if compressed integers should be used, false
300 * otherwise.
301 *
302 * @throws IllegalStateException if state can't be changed.
303 */
304 public native void setCompressedIntegers(boolean compressed) throws IllegalStateException;
305
306 /**
307 * Set stack depth.
308 *
309 * @param depth
310 *
311 * @throws IllegalArgumentException if not within a valid range
312 * @throws IllegalStateException if depth can't be changed
313 */
314 public native void setStackDepth(int depth) throws IllegalArgumentException, IllegalStateException;
315
316 /**
317 * Turn on stack trace for an event
318 *
319 * @param eventTypeId the event id
320 *
321 * @param enabled if stack traces should be enabled
322 */
323 public native void setStackTraceEnabled(long eventTypeId, boolean enabled);
324
325 /**
326 * Set thread buffer size.
327 *
328 * @param size
329 *
330 * @throws IllegalArgumentException if size is not within a valid range
331 * @throws IllegalStateException if size can't be changed
332 */
333 public native void setThreadBufferSize(long size) throws IllegalArgumentException, IllegalStateException;
334
335 /**
336 * Set threshold for event,
337 *
338 * Long.MAXIMUM_VALUE = no limit
339 *
340 * @param eventTypeId the id of the event type
341 * @param ticks threshold in ticks,
342 * @return true, if it could be set
343 */
344 public native boolean setThreshold(long eventTypeId, long ticks);
345
346 /**
347 * Store the metadata descriptor that is to be written at the end of a
348 * chunk, data should be written after GMT offset and size of metadata event
349 * should be adjusted
350 *
351 * Requires that JFR has been started with {@link #createNativeJFR()}
352 *
353 * @param bytes binary representation of metadata descriptor
354 *
355 * @param binary representation of descriptor
356 */
357 public native void storeMetadataDescriptor(byte[] bytes);
358
359 public void endRecording_() {
360 endRecording();
361 recording = false;
362 }
363
364 public void beginRecording_() {
365 beginRecording();
366 recording = true;
367 }
368
369 public boolean isRecording() {
370 return recording;
371 }
372
373 /**
374 * If the JVM supports JVM TI and retransformation has not been disabled this
375 * method will return true. This flag can not change during the lifetime of
376 * the JVM.
377 *
378 * @return if transform is allowed
379 */
380 public native boolean getAllowedToDoEventRetransforms();
381
382 /**
383 * Set up native resources, data structures, threads etc. for JFR
384 *
385 * @param simulateFailure simulate a initialization failure and rollback in
386 * native, used for testing purposes
387 *
388 * @throws IllegalStateException if native part of JFR could not be created.
389 *
390 */
391 private native boolean createJFR(boolean simulateFailure) throws IllegalStateException;
392
393 /**
394 * Destroys native part of JFR. If already destroy, call is ignored.
395 *
396 * Requires that JFR has been started with {@link #createNativeJFR()}
397 *
398 * @return if an instance was actually destroyed.
399 *
400 */
401 private native boolean destroyJFR();
402
403 public boolean createFailedNativeJFR() throws IllegalStateException {
404 return createJFR(true);
405 }
406
407 public void createNativeJFR() {
408 nativeOK = createJFR(false);
409 }
410
411 public boolean destroyNativeJFR() {
412 boolean result = destroyJFR();
413 nativeOK = !result;
414 return result;
415 }
416
417 public boolean hasNativeJFR() {
418 return nativeOK;
419 }
420
421 /**
422 * Cheap test to check if JFR functionality is available.
423 *
424 * @return
425 */
426 public native boolean isAvailable();
427
428 /**
429 * To convert ticks to wall clock time.
430 */
431 public native double getTimeConversionFactor();
432
433 /**
434 * Return a unique identifier for a class. Compared to {@link #getClassId()}
435 * , this method does not tag the class as being "in-use".
436 *
437 * @param clazz class
438 *
439 * @return a unique class identifier
440 */
441 public native long getTypeId(Class<?> clazz);
442
443 /**
444 * Fast path fetching the EventWriter using VM intrinsics
445 *
446 * @return thread local EventWriter
447 */
448 // @HotSpotIntrinsicCandidate
449 public static native Object getEventWriter();
450
451 /**
452 * Create a new EventWriter
453 *
454 * @return thread local EventWriter
455 */
456 public static native EventWriter newEventWriter();
457
458 /**
459 * Flushes the EventWriter for this thread.
460 */
461 public static native boolean flush(EventWriter writer, int uncommittedSize, int requestedSize);
462
463 /**
464 * Sets the location of the disk repository, to be used at an emergency
465 * dump.
466 *
467 * @param dirText
468 */
469 public native void setRepositoryLocation(String dirText);
470
471 /**
472 * Access to VM termination support.
473 *
474 *@param errorMsg descriptive message to be include in VM termination sequence
475 */
476 public native void abort(String errorMsg);
477
478 /**
479 * Adds a string to the string constant pool.
480 *
481 * If the same string is added twice, two entries will be created.
482 *
483 * @param id identifier associated with the string, not negative
484 *
485 * @param s string constant to be added, not null
486 *
487 * @return the current epoch of this insertion attempt
488 */
489 public static native boolean addStringConstant(boolean epoch, long id, String s);
490 /**
491 * Gets the address of the jboolean epoch.
492 *
493 * The epoch alternates every checkpoint.
494 *
495 * @return The address of the jboolean.
496 */
497 public native long getEpochAddress();
498
499 public native void uncaughtException(Thread thread, Throwable t);
500 /**
501 * Sets cutoff for event.
502 *
503 * Determines how long the event should be allowed to run.
504 *
505 * Long.MAXIMUM_VALUE = no limit
506 *
507 * @param eventTypeId the id of the event type
508 * @param cutoffTicks cutoff in ticks,
509 * @return true, if it could be set
510 */
511 public native boolean setCutoff(long eventTypeId, long cutoffTicks);
512
513 /**
514 * Emit old object sample events.
515 *
516 * @param cutoff the cutoff in ticks
517 * @param emitAll emit all samples in old object queue
518 */
519 public native void emitOldObjectSamples(long cutoff, boolean emitAll);
520
521 /**
522 * Test if a chunk rotation is warranted.
523 *
524 * @return if it is time to perform a chunk rotation
525 */
526 public native boolean shouldRotateDisk();
527 }