1 /*
2 * Copyright (c) 2015, 2019, Red Hat, Inc. All rights reserved.
3 *
4 * This code is free software; you can redistribute it and/or modify it
5 * under the terms of the GNU General Public License version 2 only, as
6 * published by the Free Software Foundation.
7 *
8 * This code is distributed in the hope that it will be useful, but WITHOUT
9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
11 * version 2 for more details (a copy is included in the LICENSE file that
12 * accompanied this code).
13 *
14 * You should have received a copy of the GNU General Public License version
15 * 2 along with this work; if not, write to the Free Software Foundation,
16 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
17 *
18 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
19 * or visit www.oracle.com if you need additional information or have any
20 * questions.
21 *
22 */
23
24 #include "precompiled.hpp"
25
26 #include "classfile/classLoaderDataGraph.hpp"
27 #include "classfile/stringTable.hpp"
28 #include "classfile/systemDictionary.hpp"
29 #include "code/codeCache.hpp"
30 #include "gc/shenandoah/shenandoahRootProcessor.inline.hpp"
31 #include "gc/shenandoah/shenandoahHeap.hpp"
32 #include "gc/shenandoah/shenandoahPhaseTimings.hpp"
33 #include "gc/shenandoah/shenandoahStringDedup.hpp"
34 #include "gc/shenandoah/shenandoahTimingTracker.hpp"
35 #include "gc/shenandoah/shenandoahVMOperations.hpp"
36 #include "jfr/jfr.hpp"
37 #include "memory/iterator.hpp"
38 #include "memory/resourceArea.hpp"
39 #include "memory/universe.hpp"
40 #include "runtime/thread.hpp"
41 #include "services/management.hpp"
42
43 ShenandoahSerialRoot::ShenandoahSerialRoot(ShenandoahSerialRoot::OopsDo oops_do, ShenandoahPhaseTimings::GCParPhases phase) :
44 _oops_do(oops_do), _phase(phase) {
45 }
46
47 void ShenandoahSerialRoot::oops_do(OopClosure* cl, uint worker_id) {
48 if (_claimed.try_set()) {
49 ShenandoahWorkerTimings* worker_times = ShenandoahHeap::heap()->phase_timings()->worker_times();
50 ShenandoahWorkerTimingsTracker timer(worker_times, _phase, worker_id);
51 _oops_do(cl);
52 }
53 }
54
55 // Overwrite the second argument for SD::oops_do, don't include vm global oop storage.
56 static void system_dictionary_oops_do(OopClosure* cl) {
57 SystemDictionary::oops_do(cl, false);
58 }
59
60 ShenandoahSerialRoots::ShenandoahSerialRoots() :
61 _universe_root(&Universe::oops_do, ShenandoahPhaseTimings::UniverseRoots),
62 _object_synchronizer_root(&ObjectSynchronizer::oops_do, ShenandoahPhaseTimings::ObjectSynchronizerRoots),
63 _management_root(&Management::oops_do, ShenandoahPhaseTimings::ManagementRoots),
64 _system_dictionary_root(&system_dictionary_oops_do, ShenandoahPhaseTimings::SystemDictionaryRoots),
65 _jvmti_root(&JvmtiExport::oops_do, ShenandoahPhaseTimings::JVMTIRoots) {
66 }
67
68 void ShenandoahSerialRoots::oops_do(OopClosure* cl, uint worker_id) {
69 _universe_root.oops_do(cl, worker_id);
70 _object_synchronizer_root.oops_do(cl, worker_id);
71 _management_root.oops_do(cl, worker_id);
72 _system_dictionary_root.oops_do(cl, worker_id);
73 _jvmti_root.oops_do(cl, worker_id);
74 }
75
76 ShenandoahWeakSerialRoot::ShenandoahWeakSerialRoot(ShenandoahWeakSerialRoot::WeakOopsDo weak_oops_do, ShenandoahPhaseTimings::GCParPhases phase) :
77 _weak_oops_do(weak_oops_do), _phase(phase) {
78 }
79
80 void ShenandoahWeakSerialRoot::weak_oops_do(BoolObjectClosure* is_alive, OopClosure* keep_alive, uint worker_id) {
81 if (_claimed.try_set()) {
82 ShenandoahWorkerTimings* worker_times = ShenandoahHeap::heap()->phase_timings()->worker_times();
83 ShenandoahWorkerTimingsTracker timer(worker_times, _phase, worker_id);
84 _weak_oops_do(is_alive, keep_alive);
85 }
86 }
87
88 #if INCLUDE_JVMTI
89 ShenandoahJVMTIWeakRoot::ShenandoahJVMTIWeakRoot() :
90 ShenandoahWeakSerialRoot(&JvmtiExport::weak_oops_do, ShenandoahPhaseTimings::JVMTIWeakRoots) {
91 }
92 #endif // INCLUDE_JVMTI
93
94 #if INCLUDE_JFR
95 ShenandoahJFRWeakRoot::ShenandoahJFRWeakRoot() :
96 ShenandoahWeakSerialRoot(&Jfr::weak_oops_do, ShenandoahPhaseTimings::JFRWeakRoots) {
97 }
98 #endif // INCLUDE_JFR
99
100 void ShenandoahSerialWeakRoots::weak_oops_do(BoolObjectClosure* is_alive, OopClosure* keep_alive, uint worker_id) {
101 JVMTI_ONLY(_jvmti_weak_roots.weak_oops_do(is_alive, keep_alive, worker_id);)
102 JFR_ONLY(_jfr_weak_roots.weak_oops_do(is_alive, keep_alive, worker_id);)
103 }
104
105 void ShenandoahSerialWeakRoots::weak_oops_do(OopClosure* cl, uint worker_id) {
106 AlwaysTrueClosure always_true;
107 weak_oops_do(&always_true, cl, worker_id);
108 }
109
110 ShenandoahThreadRoots::ShenandoahThreadRoots(bool is_par) : _is_par(is_par) {
111 Threads::change_thread_claim_token();
112 }
113
114 void ShenandoahThreadRoots::oops_do(OopClosure* oops_cl, CodeBlobClosure* code_cl, uint worker_id) {
115 ShenandoahWorkerTimings* worker_times = ShenandoahHeap::heap()->phase_timings()->worker_times();
116 ShenandoahWorkerTimingsTracker timer(worker_times, ShenandoahPhaseTimings::ThreadRoots, worker_id);
117 ResourceMark rm;
118 Threads::possibly_parallel_oops_do(_is_par, oops_cl, code_cl);
119 }
120
121 void ShenandoahThreadRoots::threads_do(ThreadClosure* tc, uint worker_id) {
122 ShenandoahWorkerTimings* worker_times = ShenandoahHeap::heap()->phase_timings()->worker_times();
123 ShenandoahWorkerTimingsTracker timer(worker_times, ShenandoahPhaseTimings::ThreadRoots, worker_id);
124 ResourceMark rm;
125 Threads::possibly_parallel_threads_do(_is_par, tc);
126 }
127
128 ShenandoahThreadRoots::~ShenandoahThreadRoots() {
129 Threads::assert_all_threads_claimed();
130 }
131
132 ShenandoahStringDedupRoots::ShenandoahStringDedupRoots() {
133 if (ShenandoahStringDedup::is_enabled()) {
134 StringDedup::gc_prologue(false);
135 }
136 }
137
138 ShenandoahStringDedupRoots::~ShenandoahStringDedupRoots() {
139 if (ShenandoahStringDedup::is_enabled()) {
140 StringDedup::gc_epilogue();
141 }
142 }
143
144 void ShenandoahStringDedupRoots::oops_do(BoolObjectClosure* is_alive, OopClosure* keep_alive, uint worker_id) {
145 if (ShenandoahStringDedup::is_enabled()) {
146 ShenandoahStringDedup::parallel_oops_do(is_alive, keep_alive, worker_id);
147 }
148 }
149
150 ShenandoahRootProcessor::ShenandoahRootProcessor(ShenandoahPhaseTimings::Phase phase) :
151 _heap(ShenandoahHeap::heap()),
152 _phase(phase) {
153 assert(SafepointSynchronize::is_at_safepoint(), "Must at safepoint");
154 _heap->phase_timings()->record_workers_start(_phase);
155 }
156
157 ShenandoahRootProcessor::~ShenandoahRootProcessor() {
158 assert(SafepointSynchronize::is_at_safepoint(), "Must at safepoint");
159 _heap->phase_timings()->record_workers_end(_phase);
160 }
161
162 ShenandoahRootEvacuator::ShenandoahRootEvacuator(uint n_workers, ShenandoahPhaseTimings::Phase phase, bool include_concurrent_roots) :
163 ShenandoahRootProcessor(phase),
164 _thread_roots(n_workers > 1),
165 _include_concurrent_roots(include_concurrent_roots) {
166 }
167
168 void ShenandoahRootEvacuator::roots_do(uint worker_id, OopClosure* oops) {
169 MarkingCodeBlobClosure blobsCl(oops, CodeBlobToOopClosure::FixRelocations);
170 AlwaysTrueClosure always_true;
171
172 _serial_roots.oops_do(oops, worker_id);
173 _serial_weak_roots.weak_oops_do(oops, worker_id);
174 if (_include_concurrent_roots) {
175 CLDToOopClosure clds(oops, ClassLoaderData::_claim_strong);
176 _vm_roots.oops_do<OopClosure>(oops, worker_id);
177 _cld_roots.cld_do(&clds, worker_id);
178 _weak_roots.oops_do<OopClosure>(oops, worker_id);
179 }
180
181 _thread_roots.oops_do(oops, NULL, worker_id);
182 _code_roots.code_blobs_do(&blobsCl, worker_id);
183
184 _dedup_roots.oops_do(&always_true, oops, worker_id);
185 }
186
187 ShenandoahRootUpdater::ShenandoahRootUpdater(uint n_workers, ShenandoahPhaseTimings::Phase phase) :
188 ShenandoahRootProcessor(phase),
189 _thread_roots(n_workers > 1) {
190 }
191
192 ShenandoahRootAdjuster::ShenandoahRootAdjuster(uint n_workers, ShenandoahPhaseTimings::Phase phase) :
193 ShenandoahRootProcessor(phase),
194 _thread_roots(n_workers > 1) {
195 assert(ShenandoahHeap::heap()->is_full_gc_in_progress(), "Full GC only");
196 }
197
198 void ShenandoahRootAdjuster::roots_do(uint worker_id, OopClosure* oops) {
199 CodeBlobToOopClosure adjust_code_closure(oops, CodeBlobToOopClosure::FixRelocations);
200 CLDToOopClosure adjust_cld_closure(oops, ClassLoaderData::_claim_strong);
201 AlwaysTrueClosure always_true;
202
203 _serial_roots.oops_do(oops, worker_id);
204 _vm_roots.oops_do(oops, worker_id);
205
206 _thread_roots.oops_do(oops, NULL, worker_id);
207 _cld_roots.cld_do(&adjust_cld_closure, worker_id);
208 _code_roots.code_blobs_do(&adjust_code_closure, worker_id);
209
210 _serial_weak_roots.weak_oops_do(oops, worker_id);
211 _weak_roots.oops_do<OopClosure>(oops, worker_id);
212 _dedup_roots.oops_do(&always_true, oops, worker_id);
213 }
214
215 ShenandoahHeapIterationRootScanner::ShenandoahHeapIterationRootScanner() :
216 ShenandoahRootProcessor(ShenandoahPhaseTimings::_num_phases),
217 _thread_roots(false /*is par*/) {
218 }
219
220 void ShenandoahHeapIterationRootScanner::roots_do(OopClosure* oops) {
221 assert(Thread::current()->is_VM_thread(), "Only by VM thread");
222 // Must use _claim_none to avoid interfering with concurrent CLDG iteration
223 CLDToOopClosure clds(oops, ClassLoaderData::_claim_none);
224 MarkingCodeBlobClosure code(oops, !CodeBlobToOopClosure::FixRelocations);
225 ShenandoahParallelOopsDoThreadClosure tc_cl(oops, &code, NULL);
226 AlwaysTrueClosure always_true;
227 ResourceMark rm;
228
229 _serial_roots.oops_do(oops, 0);
230 _vm_roots.oops_do(oops, 0);
231 _cld_roots.cld_do(&clds, 0);
232 _thread_roots.threads_do(&tc_cl, 0);
233 _code_roots.code_blobs_do(&code, 0);
234
235 _serial_weak_roots.weak_oops_do(oops, 0);
236 _weak_roots.oops_do<OopClosure>(oops, 0);
237 _dedup_roots.oops_do(&always_true, oops, 0);
238 }
239
240 void ShenandoahHeapIterationRootScanner::strong_roots_do(OopClosure* oops) {
241 assert(Thread::current()->is_VM_thread(), "Only by VM thread");
242 // Must use _claim_none to avoid interfering with concurrent CLDG iteration
243 CLDToOopClosure clds(oops, ClassLoaderData::_claim_none);
244 MarkingCodeBlobClosure code(oops, !CodeBlobToOopClosure::FixRelocations);
245 ShenandoahParallelOopsDoThreadClosure tc_cl(oops, &code, NULL);
246 ResourceMark rm;
247
248 _serial_roots.oops_do(oops, 0);
249 _vm_roots.oops_do(oops, 0);
250 _cld_roots.always_strong_cld_do(&clds, 0);
251 _thread_roots.threads_do(&tc_cl, 0);
252 }