1 /*
2 * Copyright (c) 2015, 2019, 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 #include "precompiled.hpp"
25 #include "classfile/classLoaderDataGraph.hpp"
26 #include "classfile/stringTable.hpp"
27 #include "classfile/systemDictionary.hpp"
28 #include "code/codeCache.hpp"
29 #include "compiler/oopMap.hpp"
30 #include "gc/shared/barrierSet.hpp"
31 #include "gc/shared/barrierSetNMethod.hpp"
32 #include "gc/shared/oopStorageParState.inline.hpp"
33 #include "gc/shared/oopStorageSet.hpp"
34 #include "gc/shared/suspendibleThreadSet.hpp"
35 #include "gc/z/zBarrierSetNMethod.hpp"
36 #include "gc/z/zGlobals.hpp"
37 #include "gc/z/zNMethod.hpp"
38 #include "gc/z/zOopClosures.inline.hpp"
39 #include "gc/z/zRootsIterator.hpp"
40 #include "gc/z/zStat.hpp"
41 #include "gc/z/zThreadLocalData.hpp"
42 #include "memory/iterator.hpp"
43 #include "memory/resourceArea.hpp"
44 #include "memory/universe.hpp"
45 #include "prims/jvmtiExport.hpp"
46 #include "prims/resolvedMethodTable.hpp"
47 #include "runtime/atomic.hpp"
48 #include "runtime/thread.hpp"
49 #include "runtime/safepoint.hpp"
50 #include "runtime/synchronizer.hpp"
51 #include "services/management.hpp"
52 #include "utilities/debug.hpp"
53 #if INCLUDE_JFR
54 #include "jfr/jfr.hpp"
55 #endif
56
57 static const ZStatSubPhase ZSubPhasePauseRootsSetup("Pause Roots Setup");
58 static const ZStatSubPhase ZSubPhasePauseRoots("Pause Roots");
59 static const ZStatSubPhase ZSubPhasePauseRootsTeardown("Pause Roots Teardown");
60 static const ZStatSubPhase ZSubPhasePauseRootsUniverse("Pause Roots Universe");
61 static const ZStatSubPhase ZSubPhasePauseRootsObjectSynchronizer("Pause Roots ObjectSynchronizer");
62 static const ZStatSubPhase ZSubPhasePauseRootsManagement("Pause Roots Management");
63 static const ZStatSubPhase ZSubPhasePauseRootsJVMTIExport("Pause Roots JVMTIExport");
64 static const ZStatSubPhase ZSubPhasePauseRootsJVMTIWeakExport("Pause Roots JVMTIWeakExport");
65 static const ZStatSubPhase ZSubPhasePauseRootsSystemDictionary("Pause Roots SystemDictionary");
66 static const ZStatSubPhase ZSubPhasePauseRootsThreads("Pause Roots Threads");
67 static const ZStatSubPhase ZSubPhasePauseRootsCodeCache("Pause Roots CodeCache");
68
69 static const ZStatSubPhase ZSubPhaseConcurrentRootsSetup("Concurrent Roots Setup");
70 static const ZStatSubPhase ZSubPhaseConcurrentRoots("Concurrent Roots");
71 static const ZStatSubPhase ZSubPhaseConcurrentRootsTeardown("Concurrent Roots Teardown");
72 static const ZStatSubPhase ZSubPhaseConcurrentRootsJNIHandles("Concurrent Roots JNIHandles");
73 static const ZStatSubPhase ZSubPhaseConcurrentRootsVMHandles("Concurrent Roots VMHandles");
74 static const ZStatSubPhase ZSubPhaseConcurrentRootsClassLoaderDataGraph("Concurrent Roots ClassLoaderDataGraph");
75
76 static const ZStatSubPhase ZSubPhasePauseWeakRootsSetup("Pause Weak Roots Setup");
77 static const ZStatSubPhase ZSubPhasePauseWeakRoots("Pause Weak Roots");
78 static const ZStatSubPhase ZSubPhasePauseWeakRootsTeardown("Pause Weak Roots Teardown");
79 static const ZStatSubPhase ZSubPhasePauseWeakRootsJVMTIWeakExport("Pause Weak Roots JVMTIWeakExport");
80 static const ZStatSubPhase ZSubPhasePauseWeakRootsJFRWeak("Pause Weak Roots JFRWeak");
81
82 static const ZStatSubPhase ZSubPhaseConcurrentWeakRoots("Concurrent Weak Roots");
83 static const ZStatSubPhase ZSubPhaseConcurrentWeakRootsVMWeakHandles("Concurrent Weak Roots VMWeakHandles");
84 static const ZStatSubPhase ZSubPhaseConcurrentWeakRootsJNIWeakHandles("Concurrent Weak Roots JNIWeakHandles");
85 static const ZStatSubPhase ZSubPhaseConcurrentWeakRootsStringTable("Concurrent Weak Roots StringTable");
86 static const ZStatSubPhase ZSubPhaseConcurrentWeakRootsResolvedMethodTable("Concurrent Weak Roots ResolvedMethodTable");
87
88 template <typename T, void (T::*F)(ZRootsIteratorClosure*)>
ZSerialOopsDo(T * iter)89 ZSerialOopsDo<T, F>::ZSerialOopsDo(T* iter) :
90 _iter(iter),
91 _claimed(false) {}
92
93 template <typename T, void (T::*F)(ZRootsIteratorClosure*)>
oops_do(ZRootsIteratorClosure * cl)94 void ZSerialOopsDo<T, F>::oops_do(ZRootsIteratorClosure* cl) {
95 if (!_claimed && Atomic::cmpxchg(&_claimed, false, true) == false) {
96 (_iter->*F)(cl);
97 }
98 }
99
100 template <typename T, void (T::*F)(ZRootsIteratorClosure*)>
ZParallelOopsDo(T * iter)101 ZParallelOopsDo<T, F>::ZParallelOopsDo(T* iter) :
102 _iter(iter),
103 _completed(false) {}
104
105 template <typename T, void (T::*F)(ZRootsIteratorClosure*)>
oops_do(ZRootsIteratorClosure * cl)106 void ZParallelOopsDo<T, F>::oops_do(ZRootsIteratorClosure* cl) {
107 if (!_completed) {
108 (_iter->*F)(cl);
109 if (!_completed) {
110 _completed = true;
111 }
112 }
113 }
114
115 template <typename T, void (T::*F)(BoolObjectClosure*, ZRootsIteratorClosure*)>
ZSerialWeakOopsDo(T * iter)116 ZSerialWeakOopsDo<T, F>::ZSerialWeakOopsDo(T* iter) :
117 _iter(iter),
118 _claimed(false) {}
119
120 template <typename T, void (T::*F)(BoolObjectClosure*, ZRootsIteratorClosure*)>
weak_oops_do(BoolObjectClosure * is_alive,ZRootsIteratorClosure * cl)121 void ZSerialWeakOopsDo<T, F>::weak_oops_do(BoolObjectClosure* is_alive, ZRootsIteratorClosure* cl) {
122 if (!_claimed && Atomic::cmpxchg(&_claimed, false, true) == false) {
123 (_iter->*F)(is_alive, cl);
124 }
125 }
126
127 template <typename T, void (T::*F)(BoolObjectClosure*, ZRootsIteratorClosure*)>
ZParallelWeakOopsDo(T * iter)128 ZParallelWeakOopsDo<T, F>::ZParallelWeakOopsDo(T* iter) :
129 _iter(iter),
130 _completed(false) {}
131
132 template <typename T, void (T::*F)(BoolObjectClosure*, ZRootsIteratorClosure*)>
weak_oops_do(BoolObjectClosure * is_alive,ZRootsIteratorClosure * cl)133 void ZParallelWeakOopsDo<T, F>::weak_oops_do(BoolObjectClosure* is_alive, ZRootsIteratorClosure* cl) {
134 if (!_completed) {
135 (_iter->*F)(is_alive, cl);
136 if (!_completed) {
137 _completed = true;
138 }
139 }
140 }
141
142 class ZRootsIteratorCodeBlobClosure : public CodeBlobClosure {
143 private:
144 ZRootsIteratorClosure* const _cl;
145 const bool _should_disarm_nmethods;
146
147 public:
ZRootsIteratorCodeBlobClosure(ZRootsIteratorClosure * cl)148 ZRootsIteratorCodeBlobClosure(ZRootsIteratorClosure* cl) :
149 _cl(cl),
150 _should_disarm_nmethods(cl->should_disarm_nmethods()) {}
151
do_code_blob(CodeBlob * cb)152 virtual void do_code_blob(CodeBlob* cb) {
153 nmethod* const nm = cb->as_nmethod_or_null();
154 if (nm != NULL && nm->oops_do_try_claim()) {
155 ZNMethod::nmethod_oops_do(nm, _cl);
156 assert(!ZNMethod::supports_entry_barrier(nm) ||
157 ZNMethod::is_armed(nm) == _should_disarm_nmethods, "Invalid state");
158 if (_should_disarm_nmethods) {
159 ZNMethod::disarm(nm);
160 }
161 }
162 }
163 };
164
165 class ZRootsIteratorThreadClosure : public ThreadClosure {
166 private:
167 ZRootsIteratorClosure* const _cl;
168
169 public:
ZRootsIteratorThreadClosure(ZRootsIteratorClosure * cl)170 ZRootsIteratorThreadClosure(ZRootsIteratorClosure* cl) :
171 _cl(cl) {}
172
do_thread(Thread * thread)173 virtual void do_thread(Thread* thread) {
174 ZRootsIteratorCodeBlobClosure code_cl(_cl);
175 thread->oops_do(_cl, ClassUnloading ? &code_cl : NULL);
176 _cl->do_thread(thread);
177 }
178 };
179
ZRootsIterator(bool visit_jvmti_weak_export)180 ZRootsIterator::ZRootsIterator(bool visit_jvmti_weak_export) :
181 _visit_jvmti_weak_export(visit_jvmti_weak_export),
182 _universe(this),
183 _object_synchronizer(this),
184 _management(this),
185 _jvmti_export(this),
186 _jvmti_weak_export(this),
187 _system_dictionary(this),
188 _threads(this),
189 _code_cache(this) {
190 assert(SafepointSynchronize::is_at_safepoint(), "Should be at safepoint");
191 ZStatTimer timer(ZSubPhasePauseRootsSetup);
192 Threads::change_thread_claim_token();
193 COMPILER2_OR_JVMCI_PRESENT(DerivedPointerTable::clear());
194 if (ClassUnloading) {
195 nmethod::oops_do_marking_prologue();
196 } else {
197 ZNMethod::oops_do_begin();
198 }
199 }
200
~ZRootsIterator()201 ZRootsIterator::~ZRootsIterator() {
202 ZStatTimer timer(ZSubPhasePauseRootsTeardown);
203 ResourceMark rm;
204 if (ClassUnloading) {
205 nmethod::oops_do_marking_epilogue();
206 } else {
207 ZNMethod::oops_do_end();
208 }
209
210 COMPILER2_OR_JVMCI_PRESENT(DerivedPointerTable::update_pointers());
211 Threads::assert_all_threads_claimed();
212 }
213
do_universe(ZRootsIteratorClosure * cl)214 void ZRootsIterator::do_universe(ZRootsIteratorClosure* cl) {
215 ZStatTimer timer(ZSubPhasePauseRootsUniverse);
216 Universe::oops_do(cl);
217 }
218
do_object_synchronizer(ZRootsIteratorClosure * cl)219 void ZRootsIterator::do_object_synchronizer(ZRootsIteratorClosure* cl) {
220 ZStatTimer timer(ZSubPhasePauseRootsObjectSynchronizer);
221 ObjectSynchronizer::oops_do(cl);
222 }
223
do_management(ZRootsIteratorClosure * cl)224 void ZRootsIterator::do_management(ZRootsIteratorClosure* cl) {
225 ZStatTimer timer(ZSubPhasePauseRootsManagement);
226 Management::oops_do(cl);
227 }
228
do_jvmti_export(ZRootsIteratorClosure * cl)229 void ZRootsIterator::do_jvmti_export(ZRootsIteratorClosure* cl) {
230 ZStatTimer timer(ZSubPhasePauseRootsJVMTIExport);
231 JvmtiExport::oops_do(cl);
232 }
233
do_jvmti_weak_export(ZRootsIteratorClosure * cl)234 void ZRootsIterator::do_jvmti_weak_export(ZRootsIteratorClosure* cl) {
235 ZStatTimer timer(ZSubPhasePauseRootsJVMTIWeakExport);
236 AlwaysTrueClosure always_alive;
237 JvmtiExport::weak_oops_do(&always_alive, cl);
238 }
239
do_system_dictionary(ZRootsIteratorClosure * cl)240 void ZRootsIterator::do_system_dictionary(ZRootsIteratorClosure* cl) {
241 ZStatTimer timer(ZSubPhasePauseRootsSystemDictionary);
242 // Handles are processed via _vm_handles.
243 SystemDictionary::oops_do(cl, false /* include_handles */);
244 }
245
do_threads(ZRootsIteratorClosure * cl)246 void ZRootsIterator::do_threads(ZRootsIteratorClosure* cl) {
247 ZStatTimer timer(ZSubPhasePauseRootsThreads);
248 ResourceMark rm;
249 ZRootsIteratorThreadClosure thread_cl(cl);
250 Threads::possibly_parallel_threads_do(true, &thread_cl);
251 }
252
do_code_cache(ZRootsIteratorClosure * cl)253 void ZRootsIterator::do_code_cache(ZRootsIteratorClosure* cl) {
254 ZStatTimer timer(ZSubPhasePauseRootsCodeCache);
255 ZNMethod::oops_do(cl);
256 }
257
oops_do(ZRootsIteratorClosure * cl)258 void ZRootsIterator::oops_do(ZRootsIteratorClosure* cl) {
259 ZStatTimer timer(ZSubPhasePauseRoots);
260 _universe.oops_do(cl);
261 _object_synchronizer.oops_do(cl);
262 _management.oops_do(cl);
263 _jvmti_export.oops_do(cl);
264 _system_dictionary.oops_do(cl);
265 _threads.oops_do(cl);
266 if (!ClassUnloading) {
267 _code_cache.oops_do(cl);
268 }
269 if (_visit_jvmti_weak_export) {
270 _jvmti_weak_export.oops_do(cl);
271 }
272 }
273
ZConcurrentRootsIterator(int cld_claim)274 ZConcurrentRootsIterator::ZConcurrentRootsIterator(int cld_claim) :
275 _jni_handles_iter(OopStorageSet::jni_global()),
276 _vm_handles_iter(OopStorageSet::vm_global()),
277 _cld_claim(cld_claim),
278 _jni_handles(this),
279 _vm_handles(this),
280 _class_loader_data_graph(this) {
281 ZStatTimer timer(ZSubPhaseConcurrentRootsSetup);
282 ClassLoaderDataGraph::clear_claimed_marks(cld_claim);
283 }
284
~ZConcurrentRootsIterator()285 ZConcurrentRootsIterator::~ZConcurrentRootsIterator() {
286 ZStatTimer timer(ZSubPhaseConcurrentRootsTeardown);
287 }
288
do_jni_handles(ZRootsIteratorClosure * cl)289 void ZConcurrentRootsIterator::do_jni_handles(ZRootsIteratorClosure* cl) {
290 ZStatTimer timer(ZSubPhaseConcurrentRootsJNIHandles);
291 _jni_handles_iter.oops_do(cl);
292 }
293
do_vm_handles(ZRootsIteratorClosure * cl)294 void ZConcurrentRootsIterator::do_vm_handles(ZRootsIteratorClosure* cl) {
295 ZStatTimer timer(ZSubPhaseConcurrentRootsVMHandles);
296 _vm_handles_iter.oops_do(cl);
297 }
298
do_class_loader_data_graph(ZRootsIteratorClosure * cl)299 void ZConcurrentRootsIterator::do_class_loader_data_graph(ZRootsIteratorClosure* cl) {
300 ZStatTimer timer(ZSubPhaseConcurrentRootsClassLoaderDataGraph);
301 CLDToOopClosure cld_cl(cl, _cld_claim);
302 ClassLoaderDataGraph::always_strong_cld_do(&cld_cl);
303 }
304
oops_do(ZRootsIteratorClosure * cl)305 void ZConcurrentRootsIterator::oops_do(ZRootsIteratorClosure* cl) {
306 ZStatTimer timer(ZSubPhaseConcurrentRoots);
307 _jni_handles.oops_do(cl);
308 _vm_handles.oops_do(cl),
309 _class_loader_data_graph.oops_do(cl);
310 }
311
ZWeakRootsIterator()312 ZWeakRootsIterator::ZWeakRootsIterator() :
313 _jvmti_weak_export(this),
314 _jfr_weak(this) {
315 assert(SafepointSynchronize::is_at_safepoint(), "Should be at safepoint");
316 ZStatTimer timer(ZSubPhasePauseWeakRootsSetup);
317 }
318
~ZWeakRootsIterator()319 ZWeakRootsIterator::~ZWeakRootsIterator() {
320 ZStatTimer timer(ZSubPhasePauseWeakRootsTeardown);
321 }
322
do_jvmti_weak_export(BoolObjectClosure * is_alive,ZRootsIteratorClosure * cl)323 void ZWeakRootsIterator::do_jvmti_weak_export(BoolObjectClosure* is_alive, ZRootsIteratorClosure* cl) {
324 ZStatTimer timer(ZSubPhasePauseWeakRootsJVMTIWeakExport);
325 JvmtiExport::weak_oops_do(is_alive, cl);
326 }
327
do_jfr_weak(BoolObjectClosure * is_alive,ZRootsIteratorClosure * cl)328 void ZWeakRootsIterator::do_jfr_weak(BoolObjectClosure* is_alive, ZRootsIteratorClosure* cl) {
329 #if INCLUDE_JFR
330 ZStatTimer timer(ZSubPhasePauseWeakRootsJFRWeak);
331 Jfr::weak_oops_do(is_alive, cl);
332 #endif
333 }
334
weak_oops_do(BoolObjectClosure * is_alive,ZRootsIteratorClosure * cl)335 void ZWeakRootsIterator::weak_oops_do(BoolObjectClosure* is_alive, ZRootsIteratorClosure* cl) {
336 ZStatTimer timer(ZSubPhasePauseWeakRoots);
337 _jvmti_weak_export.weak_oops_do(is_alive, cl);
338 _jfr_weak.weak_oops_do(is_alive, cl);
339 }
340
oops_do(ZRootsIteratorClosure * cl)341 void ZWeakRootsIterator::oops_do(ZRootsIteratorClosure* cl) {
342 AlwaysTrueClosure always_alive;
343 weak_oops_do(&always_alive, cl);
344 }
345
ZConcurrentWeakRootsIterator()346 ZConcurrentWeakRootsIterator::ZConcurrentWeakRootsIterator() :
347 _vm_weak_handles_iter(OopStorageSet::vm_weak()),
348 _jni_weak_handles_iter(OopStorageSet::jni_weak()),
349 _string_table_iter(OopStorageSet::string_table_weak()),
350 _resolved_method_table_iter(OopStorageSet::resolved_method_table_weak()),
351 _vm_weak_handles(this),
352 _jni_weak_handles(this),
353 _string_table(this),
354 _resolved_method_table(this) {
355 StringTable::reset_dead_counter();
356 ResolvedMethodTable::reset_dead_counter();
357 }
358
~ZConcurrentWeakRootsIterator()359 ZConcurrentWeakRootsIterator::~ZConcurrentWeakRootsIterator() {
360 StringTable::finish_dead_counter();
361 ResolvedMethodTable::finish_dead_counter();
362 }
363
do_vm_weak_handles(ZRootsIteratorClosure * cl)364 void ZConcurrentWeakRootsIterator::do_vm_weak_handles(ZRootsIteratorClosure* cl) {
365 ZStatTimer timer(ZSubPhaseConcurrentWeakRootsVMWeakHandles);
366 _vm_weak_handles_iter.oops_do(cl);
367 }
368
do_jni_weak_handles(ZRootsIteratorClosure * cl)369 void ZConcurrentWeakRootsIterator::do_jni_weak_handles(ZRootsIteratorClosure* cl) {
370 ZStatTimer timer(ZSubPhaseConcurrentWeakRootsJNIWeakHandles);
371 _jni_weak_handles_iter.oops_do(cl);
372 }
373
374 template <class Container>
375 class ZDeadCounterClosure : public ZRootsIteratorClosure {
376 private:
377 ZRootsIteratorClosure* const _cl;
378 size_t _ndead;
379
380 public:
ZDeadCounterClosure(ZRootsIteratorClosure * cl)381 ZDeadCounterClosure(ZRootsIteratorClosure* cl) :
382 _cl(cl),
383 _ndead(0) {}
384
~ZDeadCounterClosure()385 ~ZDeadCounterClosure() {
386 Container::inc_dead_counter(_ndead);
387 }
388
do_oop(oop * p)389 virtual void do_oop(oop* p) {
390 _cl->do_oop(p);
391 if (*p == NULL) {
392 _ndead++;
393 }
394 }
395
do_oop(narrowOop * p)396 virtual void do_oop(narrowOop* p) {
397 ShouldNotReachHere();
398 }
399 };
400
do_string_table(ZRootsIteratorClosure * cl)401 void ZConcurrentWeakRootsIterator::do_string_table(ZRootsIteratorClosure* cl) {
402 ZStatTimer timer(ZSubPhaseConcurrentWeakRootsStringTable);
403 ZDeadCounterClosure<StringTable> counter_cl(cl);
404 _string_table_iter.oops_do(&counter_cl);
405 }
406
do_resolved_method_table(ZRootsIteratorClosure * cl)407 void ZConcurrentWeakRootsIterator::do_resolved_method_table(ZRootsIteratorClosure* cl) {
408 ZStatTimer timer(ZSubPhaseConcurrentWeakRootsResolvedMethodTable);
409 ZDeadCounterClosure<ResolvedMethodTable> counter_cl(cl);
410 _resolved_method_table_iter.oops_do(&counter_cl);
411 }
412
oops_do(ZRootsIteratorClosure * cl)413 void ZConcurrentWeakRootsIterator::oops_do(ZRootsIteratorClosure* cl) {
414 ZStatTimer timer(ZSubPhaseConcurrentWeakRoots);
415 _vm_weak_handles.oops_do(cl);
416 _jni_weak_handles.oops_do(cl);
417 _string_table.oops_do(cl);
418 _resolved_method_table.oops_do(cl);
419 }
420