1 /*
2 * Copyright (c) 2015, 2020, 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 #ifndef SHARE_GC_SHENANDOAH_SHENANDOAHROOTPROCESSOR_HPP
25 #define SHARE_GC_SHENANDOAH_SHENANDOAHROOTPROCESSOR_HPP
26
27 #include "code/codeCache.hpp"
28 #include "gc/shared/oopStorageParState.hpp"
29 #include "gc/shenandoah/shenandoahCodeRoots.hpp"
30 #include "gc/shenandoah/shenandoahHeap.hpp"
31 #include "gc/shenandoah/shenandoahPhaseTimings.hpp"
32 #include "gc/shenandoah/shenandoahSharedVariables.hpp"
33 #include "gc/shenandoah/shenandoahUtils.hpp"
34 #include "memory/iterator.hpp"
35
36 class ShenandoahSerialRoot {
37 public:
38 typedef void (*OopsDo)(OopClosure*);
39 private:
40 ShenandoahSharedFlag _claimed;
41 const OopsDo _oops_do;
42 const ShenandoahPhaseTimings::Phase _phase;
43 const ShenandoahPhaseTimings::ParPhase _par_phase;
44
45 public:
46 ShenandoahSerialRoot(OopsDo oops_do,
47 ShenandoahPhaseTimings::Phase phase, ShenandoahPhaseTimings::ParPhase par_phase);
48 void oops_do(OopClosure* cl, uint worker_id);
49 };
50
51 class ShenandoahSerialRoots {
52 private:
53 ShenandoahSerialRoot _universe_root;
54 ShenandoahSerialRoot _object_synchronizer_root;
55 ShenandoahSerialRoot _management_root;
56 ShenandoahSerialRoot _system_dictionary_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(ShenandoahPhaseTimings::Phase phase);
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 template <typename ITR>
207 class ShenandoahCodeCacheRoots {
208 private:
209 ShenandoahPhaseTimings::Phase _phase;
210 ITR _coderoots_iterator;
211 public:
212 ShenandoahCodeCacheRoots(ShenandoahPhaseTimings::Phase phase);
213 ~ShenandoahCodeCacheRoots();
214
215 void code_blobs_do(CodeBlobClosure* blob_cl, uint worker_id);
216 };
217
218 template <bool CONCURRENT, bool SINGLE_THREADED>
219 class ShenandoahClassLoaderDataRoots {
220 private:
221 ShenandoahSharedSemaphore _semaphore;
222 ShenandoahPhaseTimings::Phase _phase;
223
224 static uint worker_count(uint n_workers) {
225 // Limit concurrency a bit, otherwise it wastes resources when workers are tripping
226 // over each other. This also leaves free workers to process other parts of the root
227 // set, while admitted workers are busy with doing the CLDG walk.
228 return MAX2(1u, MIN2(ShenandoahSharedSemaphore::max_tokens(), n_workers / 2));
229 }
230
231 public:
232 ShenandoahClassLoaderDataRoots(ShenandoahPhaseTimings::Phase phase, uint n_workers);
233 ~ShenandoahClassLoaderDataRoots();
234
235 void always_strong_cld_do(CLDClosure* clds, uint worker_id);
236 void cld_do(CLDClosure* clds, uint worker_id);
237 };
238
239 class ShenandoahRootProcessor : public StackObj {
240 private:
241 ShenandoahHeap* const _heap;
242 const ShenandoahPhaseTimings::Phase _phase;
243 const ShenandoahGCWorkerPhase _worker_phase;
244 public:
245 ShenandoahRootProcessor(ShenandoahPhaseTimings::Phase phase);
246
247 ShenandoahHeap* heap() const { return _heap; }
248 };
249
250 template <typename ITR>
251 class ShenandoahRootScanner : public ShenandoahRootProcessor {
252 private:
253 ShenandoahSerialRoots _serial_roots;
254 ShenandoahThreadRoots _thread_roots;
255 ShenandoahCodeCacheRoots<ITR> _code_roots;
256 ShenandoahVMRoots<false /*concurrent*/ > _vm_roots;
257 ShenandoahStringDedupRoots _dedup_roots;
258 ShenandoahClassLoaderDataRoots<false /*concurrent*/, false /*single threaded*/>
259 _cld_roots;
260 public:
261 ShenandoahRootScanner(uint n_workers, ShenandoahPhaseTimings::Phase phase);
262
263 // Apply oops, clds and blobs to all strongly reachable roots in the system,
264 // during class unloading cycle
265 void strong_roots_do(uint worker_id, OopClosure* cl);
266 void strong_roots_do(uint worker_id, OopClosure* oops, CLDClosure* clds, CodeBlobClosure* code, ThreadClosure* tc = NULL);
267
268 // Apply oops, clds and blobs to all strongly reachable roots and weakly reachable
269 // roots when class unloading is disabled during this cycle
270 void roots_do(uint worker_id, OopClosure* cl);
271 void roots_do(uint worker_id, OopClosure* oops, CLDClosure* clds, CodeBlobClosure* code, ThreadClosure* tc = NULL);
272 };
273
274 typedef ShenandoahRootScanner<ShenandoahAllCodeRootsIterator> ShenandoahAllRootScanner;
275 typedef ShenandoahRootScanner<ShenandoahCsetCodeRootsIterator> ShenandoahCSetRootScanner;
276
277 // This scanner is only for SH::object_iteration() and only supports single-threaded
278 // root scanning
279 class ShenandoahHeapIterationRootScanner : public ShenandoahRootProcessor {
280 private:
281 ShenandoahSerialRoots _serial_roots;
282 ShenandoahThreadRoots _thread_roots;
283 ShenandoahVMRoots<false /*concurrent*/> _vm_roots;
284 ShenandoahClassLoaderDataRoots<false /*concurrent*/, true /*single threaded*/>
285 _cld_roots;
286 ShenandoahSerialWeakRoots _serial_weak_roots;
287 ShenandoahWeakRoots<false /*concurrent*/> _weak_roots;
288 ShenandoahStringDedupRoots _dedup_roots;
289 ShenandoahCodeCacheRoots<ShenandoahAllCodeRootsIterator> _code_roots;
290
291 public:
292 ShenandoahHeapIterationRootScanner();
293
294 void roots_do(OopClosure* cl);
295 };
296
297 // Evacuate all roots at a safepoint
298 class ShenandoahRootEvacuator : public ShenandoahRootProcessor {
299 private:
300 ShenandoahSerialRoots _serial_roots;
301 ShenandoahVMRoots<false /*concurrent*/> _vm_roots;
302 ShenandoahClassLoaderDataRoots<false /*concurrent*/, false /*single threaded*/>
303 _cld_roots;
304 ShenandoahThreadRoots _thread_roots;
305 ShenandoahSerialWeakRoots _serial_weak_roots;
306 ShenandoahWeakRoots<false /*concurrent*/> _weak_roots;
307 ShenandoahStringDedupRoots _dedup_roots;
308 ShenandoahCodeCacheRoots<ShenandoahAllCodeRootsIterator> _code_roots;
309 bool _stw_roots_processing;
310 bool _stw_class_unloading;
311 public:
312 ShenandoahRootEvacuator(uint n_workers, ShenandoahPhaseTimings::Phase phase,
313 bool stw_roots_processing, bool stw_class_unloading);
314
315 void roots_do(uint worker_id, OopClosure* oops);
316 };
317
318 // Update all roots at a safepoint
319 class ShenandoahRootUpdater : public ShenandoahRootProcessor {
320 private:
321 ShenandoahSerialRoots _serial_roots;
322 ShenandoahVMRoots<false /*concurrent*/> _vm_roots;
323 ShenandoahClassLoaderDataRoots<false /*concurrent*/, false /*single threaded*/>
324 _cld_roots;
325 ShenandoahThreadRoots _thread_roots;
326 ShenandoahSerialWeakRoots _serial_weak_roots;
327 ShenandoahWeakRoots<false /*concurrent*/> _weak_roots;
328 ShenandoahStringDedupRoots _dedup_roots;
329 ShenandoahCodeCacheRoots<ShenandoahAllCodeRootsIterator> _code_roots;
330
331 public:
332 ShenandoahRootUpdater(uint n_workers, ShenandoahPhaseTimings::Phase phase);
333
334 template<typename IsAlive, typename KeepAlive>
335 void roots_do(uint worker_id, IsAlive* is_alive, KeepAlive* keep_alive);
336 };
337
338 // Adjuster all roots at a safepoint during full gc
339 class ShenandoahRootAdjuster : 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<ShenandoahAllCodeRootsIterator> _code_roots;
350
351 public:
352 ShenandoahRootAdjuster(uint n_workers, ShenandoahPhaseTimings::Phase phase);
353
354 void roots_do(uint worker_id, OopClosure* oops);
355 };
356
357 #endif // SHARE_GC_SHENANDOAH_SHENANDOAHROOTPROCESSOR_HPP