1 /*
2 * Copyright (c) 2015, 2020, Red Hat, Inc. 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
27 #include "classfile/classLoaderDataGraph.hpp"
28 #include "classfile/stringTable.hpp"
29 #include "classfile/systemDictionary.hpp"
30 #include "code/codeCache.hpp"
31 #include "code/nmethod.hpp"
32 #include "gc/shenandoah/shenandoahClosures.inline.hpp"
33 #include "gc/shenandoah/shenandoahConcurrentRoots.hpp"
34 #include "gc/shenandoah/shenandoahRootProcessor.inline.hpp"
35 #include "gc/shenandoah/shenandoahHeap.inline.hpp"
36 #include "gc/shenandoah/shenandoahPhaseTimings.hpp"
37 #include "gc/shenandoah/shenandoahStringDedup.hpp"
38 #include "gc/shenandoah/shenandoahVMOperations.hpp"
39 #include "jfr/jfr.hpp"
40 #include "memory/iterator.hpp"
41 #include "memory/resourceArea.hpp"
42 #include "memory/universe.hpp"
43 #include "runtime/thread.hpp"
44 #include "services/management.hpp"
45
46 ShenandoahSerialRoot::ShenandoahSerialRoot(ShenandoahSerialRoot::OopsDo oops_do,
47 ShenandoahPhaseTimings::Phase phase, ShenandoahPhaseTimings::ParPhase par_phase) :
48 _oops_do(oops_do), _phase(phase), _par_phase(par_phase) {
49 }
50
51 void ShenandoahSerialRoot::oops_do(OopClosure* cl, uint worker_id) {
52 if (_claimed.try_set()) {
53 ShenandoahWorkerTimingsTracker timer(_phase, _par_phase, worker_id);
54 _oops_do(cl);
55 }
56 }
57
58 // Overwrite the second argument for SD::oops_do, don't include vm global oop storage.
59 static void system_dictionary_oops_do(OopClosure* cl) {
60 SystemDictionary::oops_do(cl, false);
61 }
62
63 ShenandoahSerialRoots::ShenandoahSerialRoots(ShenandoahPhaseTimings::Phase phase) :
64 _universe_root(&Universe::oops_do, phase, ShenandoahPhaseTimings::UniverseRoots),
65 _object_synchronizer_root(&ObjectSynchronizer::oops_do, phase, ShenandoahPhaseTimings::ObjectSynchronizerRoots),
66 _management_root(&Management::oops_do, phase, ShenandoahPhaseTimings::ManagementRoots),
67 _system_dictionary_root(&system_dictionary_oops_do, phase, ShenandoahPhaseTimings::SystemDictionaryRoots),
68 _jvmti_root(&JvmtiExport::oops_do, phase, ShenandoahPhaseTimings::JVMTIRoots) {
69 }
70
71 void ShenandoahSerialRoots::oops_do(OopClosure* cl, uint worker_id) {
72 _universe_root.oops_do(cl, worker_id);
73 _object_synchronizer_root.oops_do(cl, worker_id);
74 _management_root.oops_do(cl, worker_id);
75 _system_dictionary_root.oops_do(cl, worker_id);
76 _jvmti_root.oops_do(cl, worker_id);
77 }
78
79 ShenandoahWeakSerialRoot::ShenandoahWeakSerialRoot(ShenandoahWeakSerialRoot::WeakOopsDo weak_oops_do,
80 ShenandoahPhaseTimings::Phase phase, ShenandoahPhaseTimings::ParPhase par_phase) :
81 _weak_oops_do(weak_oops_do), _phase(phase), _par_phase(par_phase) {
82 }
83
84 void ShenandoahWeakSerialRoot::weak_oops_do(BoolObjectClosure* is_alive, OopClosure* keep_alive, uint worker_id) {
85 if (_claimed.try_set()) {
86 ShenandoahWorkerTimingsTracker timer(_phase, _par_phase, worker_id);
87 _weak_oops_do(is_alive, keep_alive);
88 }
89 }
90
91 #if INCLUDE_JVMTI
92 ShenandoahJVMTIWeakRoot::ShenandoahJVMTIWeakRoot(ShenandoahPhaseTimings::Phase phase) :
93 ShenandoahWeakSerialRoot(&JvmtiExport::weak_oops_do, phase, ShenandoahPhaseTimings::JVMTIWeakRoots) {
94 }
95 #endif // INCLUDE_JVMTI
96
97 #if INCLUDE_JFR
98 ShenandoahJFRWeakRoot::ShenandoahJFRWeakRoot(ShenandoahPhaseTimings::Phase phase) :
99 ShenandoahWeakSerialRoot(&Jfr::weak_oops_do, phase, ShenandoahPhaseTimings::JFRWeakRoots) {
100 }
101 #endif // INCLUDE_JFR
102
103 void ShenandoahSerialWeakRoots::weak_oops_do(BoolObjectClosure* is_alive, OopClosure* keep_alive, uint worker_id) {
104 JVMTI_ONLY(_jvmti_weak_roots.weak_oops_do(is_alive, keep_alive, worker_id);)
105 JFR_ONLY(_jfr_weak_roots.weak_oops_do(is_alive, keep_alive, worker_id);)
106 }
107
108 void ShenandoahSerialWeakRoots::weak_oops_do(OopClosure* cl, uint worker_id) {
109 AlwaysTrueClosure always_true;
110 weak_oops_do(&always_true, cl, worker_id);
111 }
112
113 ShenandoahThreadRoots::ShenandoahThreadRoots(ShenandoahPhaseTimings::Phase phase, bool is_par) :
114 _phase(phase), _is_par(is_par) {
115 Threads::change_thread_claim_token();
116 }
117
118 void ShenandoahThreadRoots::oops_do(OopClosure* oops_cl, CodeBlobClosure* code_cl, uint worker_id) {
119 ShenandoahWorkerTimingsTracker timer(_phase, ShenandoahPhaseTimings::ThreadRoots, worker_id);
120 ResourceMark rm;
121 Threads::possibly_parallel_oops_do(_is_par, oops_cl, code_cl);
122 }
123
124 void ShenandoahThreadRoots::threads_do(ThreadClosure* tc, uint worker_id) {
125 ShenandoahWorkerTimingsTracker timer(_phase, ShenandoahPhaseTimings::ThreadRoots, worker_id);
126 ResourceMark rm;
127 Threads::possibly_parallel_threads_do(_is_par, tc);
128 }
129
130 ShenandoahThreadRoots::~ShenandoahThreadRoots() {
131 Threads::assert_all_threads_claimed();
132 }
133
134 ShenandoahStringDedupRoots::ShenandoahStringDedupRoots(ShenandoahPhaseTimings::Phase phase) : _phase(phase) {
135 if (ShenandoahStringDedup::is_enabled()) {
136 StringDedup::gc_prologue(false);
137 }
138 }
139
140 ShenandoahStringDedupRoots::~ShenandoahStringDedupRoots() {
141 if (ShenandoahStringDedup::is_enabled()) {
142 StringDedup::gc_epilogue();
143 }
144 }
145
146 void ShenandoahStringDedupRoots::oops_do(BoolObjectClosure* is_alive, OopClosure* keep_alive, uint worker_id) {
147 if (ShenandoahStringDedup::is_enabled()) {
148 ShenandoahStringDedup::parallel_oops_do(_phase, is_alive, keep_alive, worker_id);
149 }
150 }
151
152 ShenandoahConcurrentStringDedupRoots::ShenandoahConcurrentStringDedupRoots() {
153 if (ShenandoahStringDedup::is_enabled()) {
154 StringDedupTable_lock->lock_without_safepoint_check();
155 StringDedupQueue_lock->lock_without_safepoint_check();
156 StringDedup::gc_prologue(true);
157 }
158 }
159
160 ShenandoahConcurrentStringDedupRoots::~ShenandoahConcurrentStringDedupRoots() {
161 if (ShenandoahStringDedup::is_enabled()) {
162 StringDedup::gc_epilogue();
163 StringDedupQueue_lock->unlock();
164 StringDedupTable_lock->unlock();
165 }
166 }
167
168 void ShenandoahConcurrentStringDedupRoots::oops_do(BoolObjectClosure* is_alive, OopClosure* keep_alive, uint worker_id) {
169 if (ShenandoahStringDedup::is_enabled()) {
170 assert_locked_or_safepoint_weak(StringDedupQueue_lock);
171 assert_locked_or_safepoint_weak(StringDedupTable_lock);
172
173 StringDedupUnlinkOrOopsDoClosure sd_cl(is_alive, keep_alive);
174 StringDedupQueue::unlink_or_oops_do(&sd_cl);
175 StringDedupTable::unlink_or_oops_do(&sd_cl, worker_id);
176 }
177 }
178
179 ShenandoahCodeCacheRoots::ShenandoahCodeCacheRoots(ShenandoahPhaseTimings::Phase phase) : _phase(phase) {
180 nmethod::oops_do_marking_prologue();
181 }
182
183 void ShenandoahCodeCacheRoots::code_blobs_do(CodeBlobClosure* blob_cl, uint worker_id) {
184 ShenandoahWorkerTimingsTracker timer(_phase, ShenandoahPhaseTimings::CodeCacheRoots, worker_id);
185 _coderoots_iterator.possibly_parallel_blobs_do(blob_cl);
186 }
187
188 ShenandoahCodeCacheRoots::~ShenandoahCodeCacheRoots() {
189 nmethod::oops_do_marking_epilogue();
190 }
191
192 ShenandoahRootProcessor::ShenandoahRootProcessor(ShenandoahPhaseTimings::Phase phase) :
193 _heap(ShenandoahHeap::heap()),
194 _phase(phase),
195 _worker_phase(phase) {
196 assert(SafepointSynchronize::is_at_safepoint(), "Must at safepoint");
197 }
198
199 ShenandoahRootScanner::ShenandoahRootScanner(uint n_workers, ShenandoahPhaseTimings::Phase phase) :
200 ShenandoahRootProcessor(phase),
201 _serial_roots(phase),
202 _thread_roots(phase, n_workers > 1),
203 _dedup_roots(phase) {
204 nmethod::oops_do_marking_prologue();
205 }
206
207 ShenandoahRootScanner::~ShenandoahRootScanner() {
208 nmethod::oops_do_marking_epilogue();
209 }
210
211 void ShenandoahRootScanner::roots_do(uint worker_id, OopClosure* oops) {
212 CLDToOopClosure clds_cl(oops, ClassLoaderData::_claim_strong);
213 MarkingCodeBlobClosure blobs_cl(oops, !CodeBlobToOopClosure::FixRelocations);
214 roots_do(worker_id, oops, &clds_cl, &blobs_cl);
215 }
216
217 void ShenandoahRootScanner::strong_roots_do(uint worker_id, OopClosure* oops) {
218 CLDToOopClosure clds_cl(oops, ClassLoaderData::_claim_strong);
219 MarkingCodeBlobClosure blobs_cl(oops, !CodeBlobToOopClosure::FixRelocations);
220 strong_roots_do(worker_id, oops, &clds_cl, &blobs_cl);
221 }
222
223 void ShenandoahRootScanner::roots_do(uint worker_id, OopClosure* oops, CLDClosure* clds, CodeBlobClosure* code, ThreadClosure *tc) {
224 assert(!ShenandoahSafepoint::is_at_shenandoah_safepoint() ||
225 !ShenandoahHeap::heap()->unload_classes(),
226 "Expect class unloading when Shenandoah cycle is running");
227 ResourceMark rm;
228
229 _serial_roots.oops_do(oops, worker_id);
230 ShenandoahParallelOopsDoThreadClosure tc_cl(oops, code, tc);
231 _thread_roots.threads_do(&tc_cl, worker_id);
232
233 AlwaysTrueClosure always_true;
234 _dedup_roots.oops_do(&always_true, oops, worker_id);
235 }
236
237 void ShenandoahRootScanner::strong_roots_do(uint worker_id, OopClosure* oops, CLDClosure* clds, CodeBlobClosure* code, ThreadClosure* tc) {
238 assert(ShenandoahHeap::heap()->unload_classes(), "Should be used during class unloading");
239 ShenandoahParallelOopsDoThreadClosure tc_cl(oops, code, tc);
240 ResourceMark rm;
241
242 _serial_roots.oops_do(oops, worker_id);
243 _thread_roots.threads_do(&tc_cl, worker_id);
244 }
245
246 ShenandoahRootEvacuator::ShenandoahRootEvacuator(uint n_workers,
247 ShenandoahPhaseTimings::Phase phase,
248 bool stw_roots_processing,
249 bool stw_class_unloading) :
250 ShenandoahRootProcessor(phase),
251 _serial_roots(phase),
252 _vm_roots(phase),
253 _cld_roots(phase),
254 _thread_roots(phase, n_workers > 1),
255 _serial_weak_roots(phase),
256 _weak_roots(phase),
257 _dedup_roots(phase),
258 _code_roots(phase),
259 _stw_roots_processing(stw_roots_processing),
260 _stw_class_unloading(stw_class_unloading) {
261 }
262
263 void ShenandoahRootEvacuator::roots_do(uint worker_id, OopClosure* oops) {
264 MarkingCodeBlobClosure blobsCl(oops, CodeBlobToOopClosure::FixRelocations);
265 ShenandoahCodeBlobAndDisarmClosure blobs_and_disarm_Cl(oops);
266 CodeBlobToOopClosure* codes_cl = ShenandoahConcurrentRoots::can_do_concurrent_class_unloading() ?
267 static_cast<CodeBlobToOopClosure*>(&blobs_and_disarm_Cl) :
268 static_cast<CodeBlobToOopClosure*>(&blobsCl);
269 AlwaysTrueClosure always_true;
270
271 _serial_roots.oops_do(oops, worker_id);
272 _serial_weak_roots.weak_oops_do(oops, worker_id);
273 if (_stw_roots_processing) {
274 _vm_roots.oops_do<OopClosure>(oops, worker_id);
275 _weak_roots.oops_do<OopClosure>(oops, worker_id);
276 _dedup_roots.oops_do(&always_true, oops, worker_id);
277 }
278
279 if (_stw_class_unloading) {
280 CLDToOopClosure clds(oops, ClassLoaderData::_claim_strong);
281 _cld_roots.cld_do(&clds, worker_id);
282 _code_roots.code_blobs_do(codes_cl, worker_id);
283 _thread_roots.oops_do(oops, NULL, worker_id);
284 } else {
285 _thread_roots.oops_do(oops, codes_cl, worker_id);
286 }
287 }
288
289 ShenandoahRootUpdater::ShenandoahRootUpdater(uint n_workers, ShenandoahPhaseTimings::Phase phase) :
290 ShenandoahRootProcessor(phase),
291 _serial_roots(phase),
292 _vm_roots(phase),
293 _cld_roots(phase),
294 _thread_roots(phase, n_workers > 1),
295 _serial_weak_roots(phase),
296 _weak_roots(phase),
297 _dedup_roots(phase),
298 _code_roots(phase) {
299 }
300
301 ShenandoahRootAdjuster::ShenandoahRootAdjuster(uint n_workers, ShenandoahPhaseTimings::Phase phase) :
302 ShenandoahRootProcessor(phase),
303 _serial_roots(phase),
304 _vm_roots(phase),
305 _cld_roots(phase),
306 _thread_roots(phase, n_workers > 1),
307 _serial_weak_roots(phase),
308 _weak_roots(phase),
309 _dedup_roots(phase),
310 _code_roots(phase) {
311 assert(ShenandoahHeap::heap()->is_full_gc_in_progress(), "Full GC only");
312 }
313
314 void ShenandoahRootAdjuster::roots_do(uint worker_id, OopClosure* oops) {
315 CodeBlobToOopClosure code_blob_cl(oops, CodeBlobToOopClosure::FixRelocations);
316 ShenandoahCodeBlobAndDisarmClosure blobs_and_disarm_Cl(oops);
317 CodeBlobToOopClosure* adjust_code_closure = ShenandoahConcurrentRoots::can_do_concurrent_class_unloading() ?
318 static_cast<CodeBlobToOopClosure*>(&blobs_and_disarm_Cl) :
319 static_cast<CodeBlobToOopClosure*>(&code_blob_cl);
320 CLDToOopClosure adjust_cld_closure(oops, ClassLoaderData::_claim_strong);
321 AlwaysTrueClosure always_true;
322
323 _serial_roots.oops_do(oops, worker_id);
324 _vm_roots.oops_do(oops, worker_id);
325
326 _thread_roots.oops_do(oops, NULL, worker_id);
327 _cld_roots.cld_do(&adjust_cld_closure, worker_id);
328 _code_roots.code_blobs_do(adjust_code_closure, worker_id);
329
330 _serial_weak_roots.weak_oops_do(oops, worker_id);
331 _weak_roots.oops_do<OopClosure>(oops, worker_id);
332 _dedup_roots.oops_do(&always_true, oops, worker_id);
333 }
334
335 ShenandoahHeapIterationRootScanner::ShenandoahHeapIterationRootScanner() :
336 ShenandoahRootProcessor(ShenandoahPhaseTimings::heap_iteration_roots),
337 _serial_roots(ShenandoahPhaseTimings::heap_iteration_roots),
338 _thread_roots(ShenandoahPhaseTimings::heap_iteration_roots, false /*is par*/),
339 _vm_roots(ShenandoahPhaseTimings::heap_iteration_roots),
340 _cld_roots(ShenandoahPhaseTimings::heap_iteration_roots),
341 _serial_weak_roots(ShenandoahPhaseTimings::heap_iteration_roots),
342 _weak_roots(ShenandoahPhaseTimings::heap_iteration_roots),
343 _code_roots(ShenandoahPhaseTimings::heap_iteration_roots) {
344 }
345
346 void ShenandoahHeapIterationRootScanner::roots_do(OopClosure* oops) {
347 assert(Thread::current()->is_VM_thread(), "Only by VM thread");
348 // Must use _claim_none to avoid interfering with concurrent CLDG iteration
349 CLDToOopClosure clds(oops, ClassLoaderData::_claim_none);
350 MarkingCodeBlobClosure code(oops, !CodeBlobToOopClosure::FixRelocations);
351 ShenandoahParallelOopsDoThreadClosure tc_cl(oops, &code, NULL);
352 AlwaysTrueClosure always_true;
353 ResourceMark rm;
354
355 _serial_roots.oops_do(oops, 0);
356 _vm_roots.oops_do(oops, 0);
357 _cld_roots.cld_do(&clds, 0);
358 _thread_roots.threads_do(&tc_cl, 0);
359 _code_roots.code_blobs_do(&code, 0);
360
361 _serial_weak_roots.weak_oops_do(oops, 0);
362 _weak_roots.oops_do<OopClosure>(oops, 0);
363 _dedup_roots.oops_do(&always_true, oops, 0);
364 }