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 _jvmti_root;
58 public:
59 ShenandoahSerialRoots(ShenandoahPhaseTimings::Phase phase);
60 void oops_do(OopClosure* cl, uint worker_id);
61 };
62
63 class ShenandoahWeakSerialRoot {
64 typedef void (*WeakOopsDo)(BoolObjectClosure*, OopClosure*);
65 private:
66 ShenandoahSharedFlag _claimed;
67 const WeakOopsDo _weak_oops_do;
68 const ShenandoahPhaseTimings::Phase _phase;
69 const ShenandoahPhaseTimings::ParPhase _par_phase;
70
71 public:
72 ShenandoahWeakSerialRoot(WeakOopsDo oops_do,
73 ShenandoahPhaseTimings::Phase phase, ShenandoahPhaseTimings::ParPhase par_phase);
74 void weak_oops_do(BoolObjectClosure* is_alive, OopClosure* keep_alive, uint worker_id);
75 };
76
77 #if INCLUDE_JVMTI
78 class ShenandoahJVMTIWeakRoot : public ShenandoahWeakSerialRoot {
79 public:
80 ShenandoahJVMTIWeakRoot(ShenandoahPhaseTimings::Phase phase);
81 };
82 #endif // INCLUDE_JVMTI
83
84 #if INCLUDE_JFR
85 class ShenandoahJFRWeakRoot : public ShenandoahWeakSerialRoot {
86 public:
87 ShenandoahJFRWeakRoot(ShenandoahPhaseTimings::Phase phase);
88 };
89 #endif // INCLUDE_JFR
90
91 class ShenandoahSerialWeakRoots {
92 private:
93 JVMTI_ONLY(ShenandoahJVMTIWeakRoot _jvmti_weak_roots;)
94 JFR_ONLY(ShenandoahJFRWeakRoot _jfr_weak_roots;)
95 public:
96 ShenandoahSerialWeakRoots(ShenandoahPhaseTimings::Phase phase) :
97 JVMTI_ONLY(_jvmti_weak_roots(phase))
98 JFR_ONLY(JVMTI_ONLY(COMMA)_jfr_weak_roots(phase)) {};
99 void weak_oops_do(BoolObjectClosure* is_alive, OopClosure* keep_alive, uint worker_id);
100 void weak_oops_do(OopClosure* cl, uint worker_id);
101 };
102
103 template <bool CONCURRENT>
104 class ShenandoahVMRoot {
105 private:
106 OopStorage::ParState<CONCURRENT, false /* is_const */> _itr;
107 const ShenandoahPhaseTimings::Phase _phase;
108 const ShenandoahPhaseTimings::ParPhase _par_phase;
109 public:
110 ShenandoahVMRoot(OopStorage* storage,
111 ShenandoahPhaseTimings::Phase phase, ShenandoahPhaseTimings::ParPhase par_phase);
112
113 template <typename Closure>
114 void oops_do(Closure* cl, uint worker_id);
115 };
116
117 template <bool CONCURRENT>
118 class ShenandoahWeakRoot : public ShenandoahVMRoot<CONCURRENT> {
119 public:
120 ShenandoahWeakRoot(OopStorage* storage,
121 ShenandoahPhaseTimings::Phase phase, ShenandoahPhaseTimings::ParPhase par_phase);
122 };
123
124 template <>
125 class ShenandoahWeakRoot<false /*concurrent*/> {
126 private:
127 OopStorage::ParState<false /*concurrent*/, false /*is_const*/> _itr;
128 const ShenandoahPhaseTimings::Phase _phase;
129 const ShenandoahPhaseTimings::ParPhase _par_phase;
130
131 public:
132 ShenandoahWeakRoot(OopStorage* storage,
133 ShenandoahPhaseTimings::Phase phase, ShenandoahPhaseTimings::ParPhase par_phase);
134
135 template <typename IsAliveClosure, typename KeepAliveClosure>
136 void weak_oops_do(IsAliveClosure* is_alive, KeepAliveClosure* keep_alive, uint worker_id);
137 };
138
139 template <bool CONCURRENT>
140 class ShenandoahWeakRoots {
141 private:
142 ShenandoahWeakRoot<CONCURRENT> _jni_roots;
143 ShenandoahWeakRoot<CONCURRENT> _string_table_roots;
144 ShenandoahWeakRoot<CONCURRENT> _resolved_method_table_roots;
145 ShenandoahWeakRoot<CONCURRENT> _vm_roots;
146
147 public:
148 ShenandoahWeakRoots();
149
150 template <typename Closure>
151 void oops_do(Closure* cl, uint worker_id);
152 };
153
154 template <>
155 class ShenandoahWeakRoots<false /*concurrent */> {
156 private:
157 ShenandoahWeakRoot<false /*concurrent*/> _jni_roots;
158 ShenandoahWeakRoot<false /*concurrent*/> _string_table_roots;
159 ShenandoahWeakRoot<false /*concurrent*/> _resolved_method_table_roots;
160 ShenandoahWeakRoot<false /*concurrent*/> _vm_roots;
161 public:
162 ShenandoahWeakRoots(ShenandoahPhaseTimings::Phase phase);
163
164 template <typename Closure>
165 void oops_do(Closure* cl, uint worker_id);
166
167 template <typename IsAliveClosure, typename KeepAliveClosure>
168 void weak_oops_do(IsAliveClosure* is_alive, KeepAliveClosure* keep_alive, uint worker_id);
169 };
170
171 template <bool CONCURRENT>
172 class ShenandoahVMRoots {
173 private:
174 ShenandoahVMRoot<CONCURRENT> _jni_handle_roots;
175 ShenandoahVMRoot<CONCURRENT> _vm_global_roots;
176
177 public:
178 ShenandoahVMRoots(ShenandoahPhaseTimings::Phase phase);
179
180 template <typename T>
181 void oops_do(T* cl, uint worker_id);
182 };
183
184 class ShenandoahThreadRoots {
185 private:
186 ShenandoahPhaseTimings::Phase _phase;
187 const bool _is_par;
188 public:
189 ShenandoahThreadRoots(ShenandoahPhaseTimings::Phase phase, bool is_par);
190 ~ShenandoahThreadRoots();
191
192 void oops_do(OopClosure* oops_cl, CodeBlobClosure* code_cl, uint worker_id);
193 void threads_do(ThreadClosure* tc, uint worker_id);
194 };
195
196 class ShenandoahStringDedupRoots {
197 private:
198 ShenandoahPhaseTimings::Phase _phase;
199 public:
200 ShenandoahStringDedupRoots(ShenandoahPhaseTimings::Phase phase);
201 ~ShenandoahStringDedupRoots();
202
203 void oops_do(BoolObjectClosure* is_alive, OopClosure* keep_alive, uint worker_id);
204 };
205
206 class ShenandoahConcurrentStringDedupRoots {
207 private:
208 ShenandoahPhaseTimings::Phase _phase;
209
210 public:
211 ShenandoahConcurrentStringDedupRoots(ShenandoahPhaseTimings::Phase phase);
212 ~ShenandoahConcurrentStringDedupRoots();
213
214 void oops_do(BoolObjectClosure* is_alive, OopClosure* keep_alive, uint worker_id);
215 };
216
217 class ShenandoahCodeCacheRoots {
218 private:
219 ShenandoahPhaseTimings::Phase _phase;
220 ShenandoahCodeRootsIterator _coderoots_iterator;
221 public:
222 ShenandoahCodeCacheRoots(ShenandoahPhaseTimings::Phase phase);
223 ~ShenandoahCodeCacheRoots();
224
225 void code_blobs_do(CodeBlobClosure* blob_cl, uint worker_id);
226 };
227
228 template <bool CONCURRENT, bool SINGLE_THREADED>
229 class ShenandoahClassLoaderDataRoots {
230 private:
231 ShenandoahSharedSemaphore _semaphore;
232 ShenandoahPhaseTimings::Phase _phase;
233
234 static uint worker_count(uint n_workers) {
235 // Limit concurrency a bit, otherwise it wastes resources when workers are tripping
236 // over each other. This also leaves free workers to process other parts of the root
237 // set, while admitted workers are busy with doing the CLDG walk.
238 return MAX2(1u, MIN2(ShenandoahSharedSemaphore::max_tokens(), n_workers / 2));
239 }
240
241 public:
242 ShenandoahClassLoaderDataRoots(ShenandoahPhaseTimings::Phase phase, uint n_workers);
243 ~ShenandoahClassLoaderDataRoots();
244
245 void always_strong_cld_do(CLDClosure* clds, uint worker_id);
246 void cld_do(CLDClosure* clds, uint worker_id);
247 };
248
249 class ShenandoahRootProcessor : public StackObj {
250 private:
251 ShenandoahHeap* const _heap;
252 const ShenandoahPhaseTimings::Phase _phase;
253 const ShenandoahGCWorkerPhase _worker_phase;
254 public:
255 ShenandoahRootProcessor(ShenandoahPhaseTimings::Phase phase);
256
257 ShenandoahHeap* heap() const { return _heap; }
258 };
259
260 class ShenandoahRootScanner : public ShenandoahRootProcessor {
261 private:
262 ShenandoahSerialRoots _serial_roots;
263 ShenandoahThreadRoots _thread_roots;
264
265 public:
266 ShenandoahRootScanner(uint n_workers, ShenandoahPhaseTimings::Phase phase);
267 ~ShenandoahRootScanner();
268
269 // Apply oops, clds and blobs to all strongly reachable roots in the system,
270 // during class unloading cycle
271 void strong_roots_do(uint worker_id, OopClosure* cl);
272 void strong_roots_do(uint worker_id, OopClosure* oops, CLDClosure* clds, CodeBlobClosure* code, ThreadClosure* tc = NULL);
273
274 // Apply oops, clds and blobs to all strongly reachable roots and weakly reachable
275 // roots when class unloading is disabled during this cycle
276 void roots_do(uint worker_id, OopClosure* cl);
277 void roots_do(uint worker_id, OopClosure* oops, CLDClosure* clds, CodeBlobClosure* code, ThreadClosure* tc = NULL);
278 };
279
280 template <bool CONCURRENT>
281 class ShenandoahConcurrentRootScanner {
282 private:
283 ShenandoahVMRoots<CONCURRENT> _vm_roots;
284 ShenandoahClassLoaderDataRoots<CONCURRENT, false /* single-threaded*/>
285 _cld_roots;
286 ShenandoahConcurrentStringDedupRoots _dedup_roots;
287 ShenandoahNMethodTableSnapshot* _codecache_snapshot;
288 ShenandoahPhaseTimings::Phase _phase;
289
290 public:
291 ShenandoahConcurrentRootScanner(uint n_workers, ShenandoahPhaseTimings::Phase phase);
292 ~ShenandoahConcurrentRootScanner();
293
294 void oops_do(OopClosure* oops, uint worker_id);
295 };
296
297 // This scanner is only for SH::object_iteration() and only supports single-threaded
298 // root scanning
299 class ShenandoahHeapIterationRootScanner : public ShenandoahRootProcessor {
300 private:
301 ShenandoahSerialRoots _serial_roots;
302 ShenandoahThreadRoots _thread_roots;
303 ShenandoahVMRoots<false /*concurrent*/> _vm_roots;
304 ShenandoahClassLoaderDataRoots<false /*concurrent*/, true /*single threaded*/>
305 _cld_roots;
306 ShenandoahSerialWeakRoots _serial_weak_roots;
307 ShenandoahWeakRoots<false /*concurrent*/> _weak_roots;
308 ShenandoahConcurrentStringDedupRoots _dedup_roots;
309 ShenandoahCodeCacheRoots _code_roots;
310
311 public:
312 ShenandoahHeapIterationRootScanner();
313
314 void roots_do(OopClosure* cl);
315 };
316
317 // Evacuate all roots at a safepoint
318 class ShenandoahRootEvacuator : public ShenandoahRootProcessor {
319 private:
320 ShenandoahSerialRoots _serial_roots;
321 ShenandoahVMRoots<false /*concurrent*/> _vm_roots;
322 ShenandoahClassLoaderDataRoots<false /*concurrent*/, false /*single threaded*/>
323 _cld_roots;
324 ShenandoahThreadRoots _thread_roots;
325 ShenandoahSerialWeakRoots _serial_weak_roots;
326 ShenandoahWeakRoots<false /*concurrent*/> _weak_roots;
327 ShenandoahStringDedupRoots _dedup_roots;
328 ShenandoahCodeCacheRoots _code_roots;
329 bool _stw_roots_processing;
330 bool _stw_class_unloading;
331 public:
332 ShenandoahRootEvacuator(uint n_workers, ShenandoahPhaseTimings::Phase phase,
333 bool stw_roots_processing, bool stw_class_unloading);
334
335 void roots_do(uint worker_id, OopClosure* oops);
336 };
337
338 // Update all roots at a safepoint
339 class ShenandoahRootUpdater : public ShenandoahRootProcessor {
340 private:
341 ShenandoahSerialRoots _serial_roots;
342 ShenandoahVMRoots<false /*concurrent*/> _vm_roots;
343 ShenandoahClassLoaderDataRoots<false /*concurrent*/, false /*single threaded*/>
344 _cld_roots;
345 ShenandoahThreadRoots _thread_roots;
346 ShenandoahSerialWeakRoots _serial_weak_roots;
347 ShenandoahWeakRoots<false /*concurrent*/> _weak_roots;
348 ShenandoahStringDedupRoots _dedup_roots;
349 ShenandoahCodeCacheRoots _code_roots;
350
351 public:
352 ShenandoahRootUpdater(uint n_workers, ShenandoahPhaseTimings::Phase phase);
353
354 template<typename IsAlive, typename KeepAlive>
355 void roots_do(uint worker_id, IsAlive* is_alive, KeepAlive* keep_alive);
356 };
357
358 // Adjuster all roots at a safepoint during full gc
359 class ShenandoahRootAdjuster : public ShenandoahRootProcessor {
360 private:
361 ShenandoahSerialRoots _serial_roots;
362 ShenandoahVMRoots<false /*concurrent*/> _vm_roots;
363 ShenandoahClassLoaderDataRoots<false /*concurrent*/, false /*single threaded*/>
364 _cld_roots;
365 ShenandoahThreadRoots _thread_roots;
366 ShenandoahSerialWeakRoots _serial_weak_roots;
367 ShenandoahWeakRoots<false /*concurrent*/> _weak_roots;
368 ShenandoahStringDedupRoots _dedup_roots;
369 ShenandoahCodeCacheRoots _code_roots;
370
371 public:
372 ShenandoahRootAdjuster(uint n_workers, ShenandoahPhaseTimings::Phase phase);
373
374 void roots_do(uint worker_id, OopClosure* oops);
375 };
376
377 #endif // SHARE_GC_SHENANDOAH_SHENANDOAHROOTPROCESSOR_HPP