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 #ifndef SHARE_GC_SHENANDOAH_SHENANDOAHROOTPROCESSOR_HPP
26 #define SHARE_GC_SHENANDOAH_SHENANDOAHROOTPROCESSOR_HPP
27
28 #include "code/codeCache.hpp"
29 #include "gc/shared/oopStorageParState.hpp"
30 #include "gc/shenandoah/shenandoahCodeRoots.hpp"
31 #include "gc/shenandoah/shenandoahHeap.hpp"
32 #include "gc/shenandoah/shenandoahPhaseTimings.hpp"
33 #include "gc/shenandoah/shenandoahSharedVariables.hpp"
34 #include "gc/shenandoah/shenandoahUtils.hpp"
35 #include "memory/iterator.hpp"
36
37 class ShenandoahSerialRoot {
38 public:
39 typedef void (*OopsDo)(OopClosure*);
40 private:
41 ShenandoahSharedFlag _claimed;
42 const OopsDo _oops_do;
43 const ShenandoahPhaseTimings::Phase _phase;
44 const ShenandoahPhaseTimings::ParPhase _par_phase;
45
46 public:
47 ShenandoahSerialRoot(OopsDo oops_do,
48 ShenandoahPhaseTimings::Phase phase, ShenandoahPhaseTimings::ParPhase par_phase);
49 void oops_do(OopClosure* cl, uint worker_id);
50 };
51
52 class ShenandoahSerialRoots {
53 private:
54 ShenandoahSerialRoot _universe_root;
55 ShenandoahSerialRoot _object_synchronizer_root;
56 ShenandoahSerialRoot _management_root;
57 ShenandoahSerialRoot _system_dictionary_root;
58 ShenandoahSerialRoot _jvmti_root;
59 public:
60 ShenandoahSerialRoots(ShenandoahPhaseTimings::Phase phase);
61 void oops_do(OopClosure* cl, uint worker_id);
62 };
63
64 class ShenandoahWeakSerialRoot {
65 typedef void (*WeakOopsDo)(BoolObjectClosure*, OopClosure*);
66 private:
67 ShenandoahSharedFlag _claimed;
68 const WeakOopsDo _weak_oops_do;
69 const ShenandoahPhaseTimings::Phase _phase;
70 const ShenandoahPhaseTimings::ParPhase _par_phase;
71
72 public:
73 ShenandoahWeakSerialRoot(WeakOopsDo oops_do,
74 ShenandoahPhaseTimings::Phase phase, ShenandoahPhaseTimings::ParPhase par_phase);
75 void weak_oops_do(BoolObjectClosure* is_alive, OopClosure* keep_alive, uint worker_id);
76 };
77
78 #if INCLUDE_JVMTI
79 class ShenandoahJVMTIWeakRoot : public ShenandoahWeakSerialRoot {
80 public:
81 ShenandoahJVMTIWeakRoot(ShenandoahPhaseTimings::Phase phase);
82 };
83 #endif // INCLUDE_JVMTI
84
85 #if INCLUDE_JFR
86 class ShenandoahJFRWeakRoot : public ShenandoahWeakSerialRoot {
87 public:
88 ShenandoahJFRWeakRoot(ShenandoahPhaseTimings::Phase phase);
89 };
90 #endif // INCLUDE_JFR
91
92 class ShenandoahSerialWeakRoots {
93 private:
94 JVMTI_ONLY(ShenandoahJVMTIWeakRoot _jvmti_weak_roots;)
95 JFR_ONLY(ShenandoahJFRWeakRoot _jfr_weak_roots;)
96 public:
97 ShenandoahSerialWeakRoots(ShenandoahPhaseTimings::Phase phase) :
98 JVMTI_ONLY(_jvmti_weak_roots(phase))
99 JFR_ONLY(JVMTI_ONLY(COMMA)_jfr_weak_roots(phase)) {};
100 void weak_oops_do(BoolObjectClosure* is_alive, OopClosure* keep_alive, uint worker_id);
101 void weak_oops_do(OopClosure* cl, uint worker_id);
102 };
103
104 template <bool CONCURRENT>
105 class ShenandoahVMRoot {
106 private:
107 OopStorage::ParState<CONCURRENT, false /* is_const */> _itr;
108 const ShenandoahPhaseTimings::Phase _phase;
109 const ShenandoahPhaseTimings::ParPhase _par_phase;
110 public:
111 ShenandoahVMRoot(OopStorage* storage,
112 ShenandoahPhaseTimings::Phase phase, ShenandoahPhaseTimings::ParPhase par_phase);
113
114 template <typename Closure>
115 void oops_do(Closure* cl, uint worker_id);
116 };
117
118 template <bool CONCURRENT>
119 class ShenandoahWeakRoot : public ShenandoahVMRoot<CONCURRENT> {
120 public:
121 ShenandoahWeakRoot(OopStorage* storage,
122 ShenandoahPhaseTimings::Phase phase, ShenandoahPhaseTimings::ParPhase par_phase);
123 };
124
125 template <>
126 class ShenandoahWeakRoot<false /*concurrent*/> {
127 private:
128 OopStorage::ParState<false /*concurrent*/, false /*is_const*/> _itr;
129 const ShenandoahPhaseTimings::Phase _phase;
130 const ShenandoahPhaseTimings::ParPhase _par_phase;
131
132 public:
133 ShenandoahWeakRoot(OopStorage* storage,
134 ShenandoahPhaseTimings::Phase phase, ShenandoahPhaseTimings::ParPhase par_phase);
135
136 template <typename IsAliveClosure, typename KeepAliveClosure>
137 void weak_oops_do(IsAliveClosure* is_alive, KeepAliveClosure* keep_alive, uint worker_id);
138 };
139
140 template <bool CONCURRENT>
141 class ShenandoahWeakRoots {
142 private:
143 ShenandoahWeakRoot<CONCURRENT> _jni_roots;
144 ShenandoahWeakRoot<CONCURRENT> _string_table_roots;
145 ShenandoahWeakRoot<CONCURRENT> _resolved_method_table_roots;
146 ShenandoahWeakRoot<CONCURRENT> _vm_roots;
147
148 public:
149 ShenandoahWeakRoots();
150
151 template <typename Closure>
152 void oops_do(Closure* cl, uint worker_id);
153 };
154
155 template <>
156 class ShenandoahWeakRoots<false /*concurrent */> {
157 private:
158 ShenandoahWeakRoot<false /*concurrent*/> _jni_roots;
159 ShenandoahWeakRoot<false /*concurrent*/> _string_table_roots;
160 ShenandoahWeakRoot<false /*concurrent*/> _resolved_method_table_roots;
161 ShenandoahWeakRoot<false /*concurrent*/> _vm_roots;
162 public:
163 ShenandoahWeakRoots(ShenandoahPhaseTimings::Phase phase);
164
165 template <typename Closure>
166 void oops_do(Closure* cl, uint worker_id);
167
168 template <typename IsAliveClosure, typename KeepAliveClosure>
169 void weak_oops_do(IsAliveClosure* is_alive, KeepAliveClosure* keep_alive, uint worker_id);
170 };
171
172 template <bool CONCURRENT>
173 class ShenandoahVMRoots {
174 private:
175 ShenandoahVMRoot<CONCURRENT> _jni_handle_roots;
176 ShenandoahVMRoot<CONCURRENT> _vm_global_roots;
177
178 public:
179 ShenandoahVMRoots(ShenandoahPhaseTimings::Phase phase);
180
181 template <typename T>
182 void oops_do(T* cl, uint worker_id);
183 };
184
185 class ShenandoahThreadRoots {
186 private:
187 ShenandoahPhaseTimings::Phase _phase;
188 const bool _is_par;
189 public:
190 ShenandoahThreadRoots(ShenandoahPhaseTimings::Phase phase, bool is_par);
191 ~ShenandoahThreadRoots();
192
193 void oops_do(OopClosure* oops_cl, CodeBlobClosure* code_cl, uint worker_id);
194 void threads_do(ThreadClosure* tc, uint worker_id);
195 };
196
197 class ShenandoahStringDedupRoots {
198 private:
199 ShenandoahPhaseTimings::Phase _phase;
200 public:
201 ShenandoahStringDedupRoots(ShenandoahPhaseTimings::Phase phase);
202 ~ShenandoahStringDedupRoots();
203
204 void oops_do(BoolObjectClosure* is_alive, OopClosure* keep_alive, uint worker_id);
205 };
206
207 class ShenandoahConcurrentStringDedupRoots {
208 public:
209 ShenandoahConcurrentStringDedupRoots();
210 ~ShenandoahConcurrentStringDedupRoots();
211
212 void oops_do(BoolObjectClosure* is_alive, OopClosure* keep_alive, uint worker_id);
213 };
214
215 class ShenandoahCodeCacheRoots {
216 private:
217 ShenandoahPhaseTimings::Phase _phase;
218 ShenandoahCodeRootsIterator _coderoots_iterator;
219 public:
220 ShenandoahCodeCacheRoots(ShenandoahPhaseTimings::Phase phase);
221 ~ShenandoahCodeCacheRoots();
222
223 void code_blobs_do(CodeBlobClosure* blob_cl, uint worker_id);
224 };
225
226 template <bool CONCURRENT, bool SINGLE_THREADED>
227 class ShenandoahClassLoaderDataRoots {
228 private:
229 ShenandoahSharedSemaphore _semaphore;
230 ShenandoahPhaseTimings::Phase _phase;
231
232 static uint worker_count(uint n_workers) {
233 // Limit concurrency a bit, otherwise it wastes resources when workers are tripping
234 // over each other. This also leaves free workers to process other parts of the root
235 // set, while admitted workers are busy with doing the CLDG walk.
236 return MAX2(1u, MIN2(ShenandoahSharedSemaphore::max_tokens(), n_workers / 2));
237 }
238
239 public:
240 ShenandoahClassLoaderDataRoots(ShenandoahPhaseTimings::Phase phase, uint n_workers);
241 ~ShenandoahClassLoaderDataRoots();
242
243 void always_strong_cld_do(CLDClosure* clds, uint worker_id);
244 void cld_do(CLDClosure* clds, uint worker_id);
245 };
246
247 class ShenandoahRootProcessor : public StackObj {
248 private:
249 ShenandoahHeap* const _heap;
250 const ShenandoahPhaseTimings::Phase _phase;
251 const ShenandoahGCWorkerPhase _worker_phase;
252 public:
253 ShenandoahRootProcessor(ShenandoahPhaseTimings::Phase phase);
254
255 ShenandoahHeap* heap() const { return _heap; }
256 };
257
258 class ShenandoahRootScanner : public ShenandoahRootProcessor {
259 private:
260 ShenandoahSerialRoots _serial_roots;
261 ShenandoahThreadRoots _thread_roots;
262 ShenandoahCodeCacheRoots _code_roots;
263 ShenandoahVMRoots<false /*concurrent*/ > _vm_roots;
264 ShenandoahStringDedupRoots _dedup_roots;
265 ShenandoahClassLoaderDataRoots<false /*concurrent*/, false /*single threaded*/>
266 _cld_roots;
267 public:
268 ShenandoahRootScanner(uint n_workers, ShenandoahPhaseTimings::Phase phase);
269
270 // Apply oops, clds and blobs to all strongly reachable roots in the system,
271 // during class unloading cycle
272 void strong_roots_do(uint worker_id, OopClosure* cl);
273 void strong_roots_do(uint worker_id, OopClosure* oops, CLDClosure* clds, CodeBlobClosure* code, ThreadClosure* tc = NULL);
274
275 // Apply oops, clds and blobs to all strongly reachable roots and weakly reachable
276 // roots when class unloading is disabled during this cycle
277 void roots_do(uint worker_id, OopClosure* cl);
278 void roots_do(uint worker_id, OopClosure* oops, CLDClosure* clds, CodeBlobClosure* code, ThreadClosure* tc = NULL);
279 };
280
281 // This scanner is only for SH::object_iteration() and only supports single-threaded
282 // root scanning
283 class ShenandoahHeapIterationRootScanner : public ShenandoahRootProcessor {
284 private:
285 ShenandoahSerialRoots _serial_roots;
286 ShenandoahThreadRoots _thread_roots;
287 ShenandoahVMRoots<false /*concurrent*/> _vm_roots;
288 ShenandoahClassLoaderDataRoots<false /*concurrent*/, true /*single threaded*/>
289 _cld_roots;
290 ShenandoahSerialWeakRoots _serial_weak_roots;
291 ShenandoahWeakRoots<false /*concurrent*/> _weak_roots;
292 ShenandoahConcurrentStringDedupRoots _dedup_roots;
293 ShenandoahCodeCacheRoots _code_roots;
294
295 public:
296 ShenandoahHeapIterationRootScanner();
297
298 void roots_do(OopClosure* cl);
299 };
300
301 // Evacuate all roots at a safepoint
302 class ShenandoahRootEvacuator : public ShenandoahRootProcessor {
303 private:
304 ShenandoahSerialRoots _serial_roots;
305 ShenandoahVMRoots<false /*concurrent*/> _vm_roots;
306 ShenandoahClassLoaderDataRoots<false /*concurrent*/, false /*single threaded*/>
307 _cld_roots;
308 ShenandoahThreadRoots _thread_roots;
309 ShenandoahSerialWeakRoots _serial_weak_roots;
310 ShenandoahWeakRoots<false /*concurrent*/> _weak_roots;
311 ShenandoahStringDedupRoots _dedup_roots;
312 ShenandoahCodeCacheRoots _code_roots;
313 bool _stw_roots_processing;
314 bool _stw_class_unloading;
315 public:
316 ShenandoahRootEvacuator(uint n_workers, ShenandoahPhaseTimings::Phase phase,
317 bool stw_roots_processing, bool stw_class_unloading);
318
319 void roots_do(uint worker_id, OopClosure* oops);
320 };
321
322 // Update all roots at a safepoint
323 class ShenandoahRootUpdater : public ShenandoahRootProcessor {
324 private:
325 ShenandoahSerialRoots _serial_roots;
326 ShenandoahVMRoots<false /*concurrent*/> _vm_roots;
327 ShenandoahClassLoaderDataRoots<false /*concurrent*/, false /*single threaded*/>
328 _cld_roots;
329 ShenandoahThreadRoots _thread_roots;
330 ShenandoahSerialWeakRoots _serial_weak_roots;
331 ShenandoahWeakRoots<false /*concurrent*/> _weak_roots;
332 ShenandoahStringDedupRoots _dedup_roots;
333 ShenandoahCodeCacheRoots _code_roots;
334
335 public:
336 ShenandoahRootUpdater(uint n_workers, ShenandoahPhaseTimings::Phase phase);
337
338 template<typename IsAlive, typename KeepAlive>
339 void roots_do(uint worker_id, IsAlive* is_alive, KeepAlive* keep_alive);
340 };
341
342 // Adjuster all roots at a safepoint during full gc
343 class ShenandoahRootAdjuster : public ShenandoahRootProcessor {
344 private:
345 ShenandoahSerialRoots _serial_roots;
346 ShenandoahVMRoots<false /*concurrent*/> _vm_roots;
347 ShenandoahClassLoaderDataRoots<false /*concurrent*/, false /*single threaded*/>
348 _cld_roots;
349 ShenandoahThreadRoots _thread_roots;
350 ShenandoahSerialWeakRoots _serial_weak_roots;
351 ShenandoahWeakRoots<false /*concurrent*/> _weak_roots;
352 ShenandoahStringDedupRoots _dedup_roots;
353 ShenandoahCodeCacheRoots _code_roots;
354
355 public:
356 ShenandoahRootAdjuster(uint n_workers, ShenandoahPhaseTimings::Phase phase);
357
358 void roots_do(uint worker_id, OopClosure* oops);
359 };
360
361 #endif // SHARE_GC_SHENANDOAH_SHENANDOAHROOTPROCESSOR_HPP