1 /*
2 * Copyright (c) 2014, 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.
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 #include "precompiled.hpp"
26 //#include "classfile/stringTable.hpp"
27 //#include "gc_interface/strongRootsScope.hpp"
28 #include "jfr/leakprofiler/utilities/unifiedOop.hpp"
29 #include "jfr/leakprofiler/checkpoint/rootResolver.hpp"
30 #include "memory/iterator.hpp"
31 #include "oops/klass.hpp"
32 #include "oops/markOop.hpp"
33 #include "oops/oop.hpp"
34 #include "prims/jvmtiThreadState.hpp"
35 #include "prims/privilegedStack.hpp"
36 #include "runtime/frame.inline.hpp"
37 #include "runtime/mutexLocker.hpp"
38 #include "runtime/vframe_hp.hpp"
39 #include "services/management.hpp"
40 #include "utilities/growableArray.hpp"
41
42 class ReferenceLocateClosure : public OopClosure {
43 protected:
44 RootCallback& _callback;
45 RootCallbackInfo _info;
46 bool _complete;
47
48 void do_oop_shared(const void* ref);
49
50 public:
51 ReferenceLocateClosure(RootCallback& callback,
52 OldObjectRoot::System system,
53 OldObjectRoot::Type type,
54 const void* context) : _callback(callback),
55 _info(),
56 _complete(false) {
57 _info._high = NULL;
58 _info._low = NULL;
59 _info._system = system;
60 _info._type = type;
61 _info._context = context;
62 }
63
64 virtual void do_oop(oop* ref);
65 virtual void do_oop(narrowOop* ref);
66
67 bool complete() const {
68 return _complete;
69 }
70 };
71
72 void ReferenceLocateClosure::do_oop_shared(const void* ref) {
73 assert(ref != NULL, "invariant");
74 if (!_complete) {
75 _info._high = ref;
76 _complete = _callback.process(_info);
77 }
78 }
79
80 void ReferenceLocateClosure::do_oop(oop* ref) {
81 do_oop_shared(ref);
82 }
83
84 void ReferenceLocateClosure::do_oop(narrowOop* ref) {
85 do_oop_shared(ref);
86 }
87
88 class ReferenceToRootClosure : public StackObj {
89 private:
90 RootCallback& _callback;
91 RootCallbackInfo _info;
92 bool _complete;
93
94 bool do_cldg_roots();
95 bool do_object_synchronizer_roots();
96 bool do_universe_roots();
97 bool do_jni_handle_roots();
98 bool do_jvmti_roots();
99 bool do_system_dictionary_roots();
100 bool do_management_roots();
101 bool do_string_table_roots();
102 // bool do_aot_loader_roots();
103
104 bool do_roots();
105
106 public:
107 ReferenceToRootClosure(RootCallback& callback) : _callback(callback),
108 _info(),
109 _complete(false) {
110 _info._high = NULL;
111 _info._low = NULL;
112 _info._context = NULL;
113 _info._system = OldObjectRoot::_system_undetermined;
114 _info._type = OldObjectRoot::_type_undetermined;
115
116 assert_locked_or_safepoint(Threads_lock);
117 do_roots();
118 }
119
120 bool complete() const {
121 return _complete;
122 }
123 };
124
125 bool ReferenceToRootClosure::do_cldg_roots() {
126 assert(!complete(), "invariant");
127 ReferenceLocateClosure rlc(_callback, OldObjectRoot::_class_loader_data, OldObjectRoot::_type_undetermined, NULL);
128 CLDToOopClosure cldt_closure(&rlc);
129 ClassLoaderDataGraph::always_strong_cld_do(&cldt_closure);
130 return rlc.complete();
131 }
132
133 bool ReferenceToRootClosure::do_object_synchronizer_roots() {
134 assert(!complete(), "invariant");
135 ReferenceLocateClosure rlc(_callback, OldObjectRoot::_object_synchronizer, OldObjectRoot::_type_undetermined, NULL);
136 ObjectSynchronizer::oops_do(&rlc);
137 return rlc.complete();
138 }
139
140 bool ReferenceToRootClosure::do_universe_roots() {
141 assert(!complete(), "invariant");
142 ReferenceLocateClosure rlc(_callback, OldObjectRoot::_universe, OldObjectRoot::_type_undetermined, NULL);
143 Universe::oops_do(&rlc);
144 return rlc.complete();
145 }
146
147 bool ReferenceToRootClosure::do_jni_handle_roots() {
148 assert(!complete(), "invariant");
149 ReferenceLocateClosure rlc(_callback, OldObjectRoot::_global_jni_handles, OldObjectRoot::_global_jni_handle, NULL);
150 JNIHandles::oops_do(&rlc);
151 return rlc.complete();
152 }
153
154 bool ReferenceToRootClosure::do_jvmti_roots() {
155 assert(!complete(), "invariant");
156 ReferenceLocateClosure rlc(_callback, OldObjectRoot::_jvmti, OldObjectRoot::_global_jni_handle, NULL);
157 JvmtiExport::oops_do(&rlc);
158 return rlc.complete();
159 }
160
161 bool ReferenceToRootClosure::do_system_dictionary_roots() {
162 assert(!complete(), "invariant");
163 ReferenceLocateClosure rlc(_callback, OldObjectRoot::_system_dictionary, OldObjectRoot::_type_undetermined, NULL);
164 SystemDictionary::oops_do(&rlc);
165 return rlc.complete();
166 }
167
168 bool ReferenceToRootClosure::do_management_roots() {
169 assert(!complete(), "invariant");
170 ReferenceLocateClosure rlc(_callback, OldObjectRoot::_management, OldObjectRoot::_type_undetermined, NULL);
171 Management::oops_do(&rlc);
172 return rlc.complete();
173 }
174
175 bool ReferenceToRootClosure::do_string_table_roots() {
176 assert(!complete(), "invariant");
177 ReferenceLocateClosure rlc(_callback, OldObjectRoot::_string_table, OldObjectRoot::_type_undetermined, NULL);
178 StringTable::oops_do(&rlc);
179 return rlc.complete();
180 }
181
182 //bool ReferenceToRootClosure::do_aot_loader_roots() {
183 // assert(!complete(), "invariant");
184 // ReferenceLocateClosure rcl(_callback, OldObjectRoot::_aot, OldObjectRoot::_type_undetermined, NULL);
185 // AOTLoader::oops_do(&rcl);
186 // return rcl.complete();
187 //}
188
189 bool ReferenceToRootClosure::do_roots() {
190 assert(!complete(), "invariant");
191 assert(OldObjectRoot::_system_undetermined == _info._system, "invariant");
192 assert(OldObjectRoot::_type_undetermined == _info._type, "invariant");
193
194 if (do_cldg_roots()) {
195 _complete = true;
196 return true;
197 }
198
199 if (do_object_synchronizer_roots()) {
200 _complete = true;
201 return true;
202 }
203
204 if (do_universe_roots()) {
205 _complete = true;
206 return true;
207 }
208
209 if (do_jni_handle_roots()) {
210 _complete = true;
211 return true;
212 }
213
214 if (do_jvmti_roots()) {
215 _complete = true;
216 return true;
217 }
218
219 if (do_system_dictionary_roots()) {
220 _complete = true;
221 return true;
222 }
223
224 if (do_management_roots()) {
225 _complete = true;
226 return true;
227 }
228
229 if (do_string_table_roots()) {
230 _complete = true;
231 return true;
232 }
233
234 // if (do_aot_loader_roots()) {
235 // _complete = true;
236 // return true;
237 // }
238
239 return false;
240 }
241
242 class ReferenceToThreadRootClosure : public StackObj {
243 private:
244 RootCallback& _callback;
245 bool _complete;
246
247 bool do_java_threads_oops(JavaThread* jt);
248 bool do_thread_roots(JavaThread* jt);
249 bool do_thread_stack_fast(JavaThread* jt);
250 bool do_thread_stack_detailed(JavaThread* jt);
251 bool do_thread_jni_handles(JavaThread* jt);
252 bool do_thread_handle_area(JavaThread* jt);
253
254 public:
255 ReferenceToThreadRootClosure(RootCallback& callback) :_callback(callback), _complete(false) {
256 assert_locked_or_safepoint(Threads_lock);
257 for (JavaThread *thread = Threads::first(); thread != NULL; thread = thread->next()) {
258 if (do_thread_roots(thread)) {
259 return;
260 }
261 }
262 }
263
264 bool complete() const {
265 return _complete;
266 }
267 };
268
269 bool ReferenceToThreadRootClosure::do_thread_handle_area(JavaThread* jt) {
270 assert(jt != NULL, "invariant");
271 assert(!complete(), "invariant");
272 ReferenceLocateClosure rcl(_callback, OldObjectRoot::_threads, OldObjectRoot::_handle_area, jt);
273 jt->handle_area()->oops_do(&rcl);
274 return rcl.complete();
275 }
276
277 bool ReferenceToThreadRootClosure::do_thread_jni_handles(JavaThread* jt) {
278 assert(jt != NULL, "invariant");
279 assert(!complete(), "invariant");
280
281 ReferenceLocateClosure rcl(_callback, OldObjectRoot::_threads, OldObjectRoot::_local_jni_handle, jt);
282 jt->active_handles()->oops_do(&rcl);
283 return rcl.complete();
284 }
285
286 bool ReferenceToThreadRootClosure::do_thread_stack_fast(JavaThread* jt) {
287 assert(jt != NULL, "invariant");
288 assert(!complete(), "invariant");
289
290 if (_callback.entries() == 0) {
291 _complete = true;
292 return true;
293 }
294
295 RootCallbackInfo info;
296 info._high = NULL;
297 info._low = NULL;
298 info._context = jt;
299 info._system = OldObjectRoot::_threads;
300 info._type = OldObjectRoot::_stack_variable;
301
302 for (int i = 0; i < _callback.entries(); ++i) {
303 const address adr = (address)_callback.at(i);
304 if (jt->is_in_usable_stack(adr)) {
305 info._high = adr;
306 _complete = _callback.process(info);
307 if (_complete) {
308 return true;
309 }
310 }
311 }
312 assert(!complete(), "invariant");
313 return false;
314 }
315
316 bool ReferenceToThreadRootClosure::do_thread_stack_detailed(JavaThread* jt) {
317 assert(jt != NULL, "invariant");
318 assert(!complete(), "invariant");
319
320 ReferenceLocateClosure rcl(_callback, OldObjectRoot::_threads, OldObjectRoot::_stack_variable, jt);
321
322 if (jt->has_last_Java_frame()) {
323 PrivilegedElement* const pelem = jt->privileged_stack_top();
324 if (pelem != NULL) {
325 pelem->oops_do(&rcl);
326 if (rcl.complete()) {
327 return true;
328 }
329 }
330
331 // traverse the registered growable array gc_array
332 // can't do this as it is not reachable from outside
333
334 // Traverse the monitor chunks
335 MonitorChunk* chunk = jt->monitor_chunks();
336 for (; chunk != NULL; chunk = chunk->next()) {
337 chunk->oops_do(&rcl);
338 }
339
340 if (rcl.complete()) {
341 return true;
342 }
343
344 // Traverse the execution stack
345 for (StackFrameStream fst(jt); !fst.is_done(); fst.next()) {
346 // XXX set CLDClosure to NULL
347 fst.current()->oops_do(&rcl, NULL, NULL, fst.register_map());
348 }
349
350 } // last java frame
351
352 if (rcl.complete()) {
353 return true;
354 }
355
356 GrowableArray<jvmtiDeferredLocalVariableSet*>* const list = jt->deferred_locals();
357 if (list != NULL) {
358 for (int i = 0; i < list->length(); i++) {
359 list->at(i)->oops_do(&rcl);
360 }
361 }
362
363 if (rcl.complete()) {
364 return true;
365 }
366
367 // Traverse instance variables at the end since the GC may be moving things
368 // around using this function
369 /*
370 * // can't reach these oop* from the outside
371 f->do_oop((oop*) &_threadObj);
372 f->do_oop((oop*) &_vm_result);
373 f->do_oop((oop*) &_exception_oop);
374 f->do_oop((oop*) &_pending_async_exception);
375 */
376
377 JvmtiThreadState* const jvmti_thread_state = jt->jvmti_thread_state();
378 if (jvmti_thread_state != NULL) {
379 jvmti_thread_state->oops_do(&rcl);
380 }
381
382 return rcl.complete();
383 }
384
385 bool ReferenceToThreadRootClosure::do_java_threads_oops(JavaThread* jt) {
386 assert(jt != NULL, "invariant");
387 assert(!complete(), "invariant");
388
389 ReferenceLocateClosure rcl(_callback, OldObjectRoot::_threads, OldObjectRoot::_global_jni_handle, jt);
390 jt->oops_do(&rcl, NULL, NULL);
391 return rcl.complete();
392 }
393
394 bool ReferenceToThreadRootClosure::do_thread_roots(JavaThread* jt) {
395 assert(jt != NULL, "invariant");
396
397 if (do_thread_stack_fast(jt)) {
398 _complete = true;
399 return true;
400 }
401
402 if (do_thread_jni_handles(jt)) {
403 _complete = true;
404 return true;
405 }
406
407 if (do_thread_handle_area(jt)) {
408 _complete = true;
409 return true;
410 }
411
412 if (do_thread_stack_detailed(jt)) {
413 _complete = true;
414 return true;
415 }
416
417 return false;
418 }
419
420 class RootResolverMarkScope : public MarkingCodeBlobClosure::MarkScope {
421 };
422
423 void RootResolver::resolve(RootCallback& callback) {
424
425 // Need to clear cld claim bit before starting
426 ClassLoaderDataGraph::clear_claimed_marks();
427 RootResolverMarkScope mark_scope;
428
429 // thread local roots
430 ReferenceToThreadRootClosure rtrc(callback);
431 if (rtrc.complete()) {
432 return;
433 }
434 // system global roots
435 ReferenceToRootClosure rrc(callback);
436 }