Mercurial > hg > graal-compiler
annotate src/share/vm/memory/referenceProcessor.hpp @ 1190:4788266644c1
6895236: CMS: cmsOopClosures.inline.hpp:43 assert(..., "Should remember klasses in this context")
Summary: Adjust assertion checking for ExplicitGCInvokesConcurrentAndUnloadsClasses as a reason for class unloading
Reviewed-by: ysr
| author | jmasa |
|---|---|
| date | Thu, 21 Jan 2010 11:33:32 -0800 |
| parents | 27a80744a83b |
| children | 745c853ee57f |
| rev | line source |
|---|---|
| 0 | 1 /* |
| 196 | 2 * Copyright 2001-2008 Sun Microsystems, Inc. All Rights Reserved. |
| 0 | 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, | |
| 20 * CA 95054 USA or visit www.sun.com if you need additional information or | |
| 21 * have any questions. | |
| 22 * | |
| 23 */ | |
| 24 | |
| 25 // ReferenceProcessor class encapsulates the per-"collector" processing | |
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26 // of java.lang.Reference objects for GC. The interface is useful for supporting |
| 0 | 27 // a generational abstraction, in particular when there are multiple |
| 28 // generations that are being independently collected -- possibly | |
| 29 // concurrently and/or incrementally. Note, however, that the | |
| 30 // ReferenceProcessor class abstracts away from a generational setting | |
| 31 // by using only a heap interval (called "span" below), thus allowing | |
| 32 // its use in a straightforward manner in a general, non-generational | |
| 33 // setting. | |
| 34 // | |
| 35 // The basic idea is that each ReferenceProcessor object concerns | |
| 36 // itself with ("weak") reference processing in a specific "span" | |
| 37 // of the heap of interest to a specific collector. Currently, | |
| 38 // the span is a convex interval of the heap, but, efficiency | |
| 39 // apart, there seems to be no reason it couldn't be extended | |
| 40 // (with appropriate modifications) to any "non-convex interval". | |
| 41 | |
| 42 // forward references | |
| 43 class ReferencePolicy; | |
| 44 class AbstractRefProcTaskExecutor; | |
| 45 class DiscoveredList; | |
| 46 | |
| 47 class ReferenceProcessor : public CHeapObj { | |
| 48 protected: | |
| 49 // End of list marker | |
| 50 static oop _sentinelRef; | |
| 51 MemRegion _span; // (right-open) interval of heap | |
| 52 // subject to wkref discovery | |
| 53 bool _discovering_refs; // true when discovery enabled | |
| 54 bool _discovery_is_atomic; // if discovery is atomic wrt | |
| 55 // other collectors in configuration | |
| 56 bool _discovery_is_mt; // true if reference discovery is MT. | |
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57 // If true, setting "next" field of a discovered refs list requires |
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58 // write barrier(s). (Must be true if used in a collector in which |
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59 // elements of a discovered list may be moved during discovery: for |
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60 // example, a collector like Garbage-First that moves objects during a |
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61 // long-term concurrent marking phase that does weak reference |
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62 // discovery.) |
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63 bool _discovered_list_needs_barrier; |
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64 BarrierSet* _bs; // Cached copy of BarrierSet. |
| 0 | 65 bool _enqueuing_is_done; // true if all weak references enqueued |
| 66 bool _processing_is_mt; // true during phases when | |
| 67 // reference processing is MT. | |
| 68 int _next_id; // round-robin counter in | |
| 69 // support of work distribution | |
| 70 | |
| 71 // For collectors that do not keep GC marking information | |
| 72 // in the object header, this field holds a closure that | |
| 73 // helps the reference processor determine the reachability | |
| 74 // of an oop (the field is currently initialized to NULL for | |
| 75 // all collectors but the CMS collector). | |
| 76 BoolObjectClosure* _is_alive_non_header; | |
| 77 | |
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78 // Soft ref clearing policies |
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79 // . the default policy |
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80 static ReferencePolicy* _default_soft_ref_policy; |
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81 // . the "clear all" policy |
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82 static ReferencePolicy* _always_clear_soft_ref_policy; |
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83 // . the current policy below is either one of the above |
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84 ReferencePolicy* _current_soft_ref_policy; |
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85 |
| 0 | 86 // The discovered ref lists themselves |
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87 |
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88 // The MT'ness degree of the queues below |
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89 int _num_q; |
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90 // Arrays of lists of oops, one per thread |
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91 DiscoveredList* _discoveredSoftRefs; |
| 0 | 92 DiscoveredList* _discoveredWeakRefs; |
| 93 DiscoveredList* _discoveredFinalRefs; | |
| 94 DiscoveredList* _discoveredPhantomRefs; | |
| 95 | |
| 96 public: | |
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97 int num_q() { return _num_q; } |
| 0 | 98 DiscoveredList* discovered_soft_refs() { return _discoveredSoftRefs; } |
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99 static oop sentinel_ref() { return _sentinelRef; } |
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100 static oop* adr_sentinel_ref() { return &_sentinelRef; } |
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101 ReferencePolicy* setup_policy(bool always_clear) { |
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102 _current_soft_ref_policy = always_clear ? |
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103 _always_clear_soft_ref_policy : _default_soft_ref_policy; |
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104 _current_soft_ref_policy->setup(); // snapshot the policy threshold |
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105 return _current_soft_ref_policy; |
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106 } |
| 0 | 107 |
| 108 public: | |
| 109 // Process references with a certain reachability level. | |
| 110 void process_discovered_reflist(DiscoveredList refs_lists[], | |
| 111 ReferencePolicy* policy, | |
| 112 bool clear_referent, | |
| 113 BoolObjectClosure* is_alive, | |
| 114 OopClosure* keep_alive, | |
| 115 VoidClosure* complete_gc, | |
| 116 AbstractRefProcTaskExecutor* task_executor); | |
| 117 | |
| 118 void process_phaseJNI(BoolObjectClosure* is_alive, | |
| 119 OopClosure* keep_alive, | |
| 120 VoidClosure* complete_gc); | |
| 121 | |
| 122 // Work methods used by the method process_discovered_reflist | |
| 123 // Phase1: keep alive all those referents that are otherwise | |
| 124 // dead but which must be kept alive by policy (and their closure). | |
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125 void process_phase1(DiscoveredList& refs_list, |
| 0 | 126 ReferencePolicy* policy, |
| 127 BoolObjectClosure* is_alive, | |
| 128 OopClosure* keep_alive, | |
| 129 VoidClosure* complete_gc); | |
| 130 // Phase2: remove all those references whose referents are | |
| 131 // reachable. | |
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132 inline void process_phase2(DiscoveredList& refs_list, |
| 0 | 133 BoolObjectClosure* is_alive, |
| 134 OopClosure* keep_alive, | |
| 135 VoidClosure* complete_gc) { | |
| 136 if (discovery_is_atomic()) { | |
| 137 // complete_gc is ignored in this case for this phase | |
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138 pp2_work(refs_list, is_alive, keep_alive); |
| 0 | 139 } else { |
| 140 assert(complete_gc != NULL, "Error"); | |
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141 pp2_work_concurrent_discovery(refs_list, is_alive, |
| 0 | 142 keep_alive, complete_gc); |
| 143 } | |
| 144 } | |
| 145 // Work methods in support of process_phase2 | |
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146 void pp2_work(DiscoveredList& refs_list, |
| 0 | 147 BoolObjectClosure* is_alive, |
| 148 OopClosure* keep_alive); | |
| 149 void pp2_work_concurrent_discovery( | |
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150 DiscoveredList& refs_list, |
| 0 | 151 BoolObjectClosure* is_alive, |
| 152 OopClosure* keep_alive, | |
| 153 VoidClosure* complete_gc); | |
| 154 // Phase3: process the referents by either clearing them | |
| 155 // or keeping them alive (and their closure) | |
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156 void process_phase3(DiscoveredList& refs_list, |
| 0 | 157 bool clear_referent, |
| 158 BoolObjectClosure* is_alive, | |
| 159 OopClosure* keep_alive, | |
| 160 VoidClosure* complete_gc); | |
| 161 | |
| 162 // Enqueue references with a certain reachability level | |
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163 void enqueue_discovered_reflist(DiscoveredList& refs_list, HeapWord* pending_list_addr); |
| 0 | 164 |
| 165 // "Preclean" all the discovered reference lists | |
| 166 // by removing references with strongly reachable referents. | |
| 167 // The first argument is a predicate on an oop that indicates | |
| 168 // its (strong) reachability and the second is a closure that | |
| 169 // may be used to incrementalize or abort the precleaning process. | |
| 170 // The caller is responsible for taking care of potential | |
| 171 // interference with concurrent operations on these lists | |
| 172 // (or predicates involved) by other threads. Currently | |
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173 // only used by the CMS collector. should_unload_classes is |
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174 // used to aid assertion checking when classes are collected. |
| 0 | 175 void preclean_discovered_references(BoolObjectClosure* is_alive, |
| 176 OopClosure* keep_alive, | |
| 177 VoidClosure* complete_gc, | |
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178 YieldClosure* yield, |
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179 bool should_unload_classes); |
| 0 | 180 |
| 181 // Delete entries in the discovered lists that have | |
| 182 // either a null referent or are not active. Such | |
| 183 // Reference objects can result from the clearing | |
| 184 // or enqueueing of Reference objects concurrent | |
| 185 // with their discovery by a (concurrent) collector. | |
| 186 // For a definition of "active" see java.lang.ref.Reference; | |
| 187 // Refs are born active, become inactive when enqueued, | |
| 188 // and never become active again. The state of being | |
| 189 // active is encoded as follows: A Ref is active | |
| 190 // if and only if its "next" field is NULL. | |
| 191 void clean_up_discovered_references(); | |
| 192 void clean_up_discovered_reflist(DiscoveredList& refs_list); | |
| 193 | |
| 194 // Returns the name of the discovered reference list | |
| 195 // occupying the i / _num_q slot. | |
| 196 const char* list_name(int i); | |
| 197 | |
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198 void enqueue_discovered_reflists(HeapWord* pending_list_addr, AbstractRefProcTaskExecutor* task_executor); |
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199 |
| 0 | 200 protected: |
| 201 // "Preclean" the given discovered reference list | |
| 202 // by removing references with strongly reachable referents. | |
| 203 // Currently used in support of CMS only. | |
| 204 void preclean_discovered_reflist(DiscoveredList& refs_list, | |
| 205 BoolObjectClosure* is_alive, | |
| 206 OopClosure* keep_alive, | |
| 207 VoidClosure* complete_gc, | |
| 208 YieldClosure* yield); | |
| 209 | |
| 210 int next_id() { | |
| 211 int id = _next_id; | |
| 212 if (++_next_id == _num_q) { | |
| 213 _next_id = 0; | |
| 214 } | |
| 215 return id; | |
| 216 } | |
| 217 DiscoveredList* get_discovered_list(ReferenceType rt); | |
| 218 inline void add_to_discovered_list_mt(DiscoveredList& refs_list, oop obj, | |
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219 HeapWord* discovered_addr); |
| 0 | 220 void verify_ok_to_handle_reflists() PRODUCT_RETURN; |
| 221 | |
| 222 void abandon_partial_discovered_list(DiscoveredList& refs_list); | |
| 223 | |
| 224 // Calculate the number of jni handles. | |
| 225 unsigned int count_jni_refs(); | |
| 226 | |
| 227 // Balances reference queues. | |
| 228 void balance_queues(DiscoveredList ref_lists[]); | |
| 229 | |
| 230 // Update (advance) the soft ref master clock field. | |
| 231 void update_soft_ref_master_clock(); | |
| 232 | |
| 233 public: | |
| 234 // constructor | |
| 235 ReferenceProcessor(): | |
| 236 _span((HeapWord*)NULL, (HeapWord*)NULL), | |
| 237 _discoveredSoftRefs(NULL), _discoveredWeakRefs(NULL), | |
| 238 _discoveredFinalRefs(NULL), _discoveredPhantomRefs(NULL), | |
| 239 _discovering_refs(false), | |
| 240 _discovery_is_atomic(true), | |
| 241 _enqueuing_is_done(false), | |
| 242 _discovery_is_mt(false), | |
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243 _discovered_list_needs_barrier(false), |
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244 _bs(NULL), |
| 0 | 245 _is_alive_non_header(NULL), |
| 246 _num_q(0), | |
| 247 _processing_is_mt(false), | |
| 248 _next_id(0) | |
| 249 {} | |
| 250 | |
| 251 ReferenceProcessor(MemRegion span, bool atomic_discovery, | |
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252 bool mt_discovery, |
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253 int mt_degree = 1, |
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254 bool mt_processing = false, |
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255 bool discovered_list_needs_barrier = false); |
| 0 | 256 |
| 257 // Allocates and initializes a reference processor. | |
| 258 static ReferenceProcessor* create_ref_processor( | |
| 259 MemRegion span, | |
| 260 bool atomic_discovery, | |
| 261 bool mt_discovery, | |
| 262 BoolObjectClosure* is_alive_non_header = NULL, | |
| 263 int parallel_gc_threads = 1, | |
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264 bool mt_processing = false, |
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265 bool discovered_list_needs_barrier = false); |
| 0 | 266 // RefDiscoveryPolicy values |
| 267 enum { | |
| 268 ReferenceBasedDiscovery = 0, | |
| 269 ReferentBasedDiscovery = 1 | |
| 270 }; | |
| 271 | |
| 272 static void init_statics(); | |
| 273 | |
| 274 public: | |
| 275 // get and set "is_alive_non_header" field | |
| 276 BoolObjectClosure* is_alive_non_header() { | |
| 277 return _is_alive_non_header; | |
| 278 } | |
| 279 void set_is_alive_non_header(BoolObjectClosure* is_alive_non_header) { | |
| 280 _is_alive_non_header = is_alive_non_header; | |
| 281 } | |
| 282 | |
| 283 // get and set span | |
| 284 MemRegion span() { return _span; } | |
| 285 void set_span(MemRegion span) { _span = span; } | |
| 286 | |
| 287 // start and stop weak ref discovery | |
| 288 void enable_discovery() { _discovering_refs = true; } | |
| 289 void disable_discovery() { _discovering_refs = false; } | |
| 290 bool discovery_enabled() { return _discovering_refs; } | |
| 291 | |
| 292 // whether discovery is atomic wrt other collectors | |
| 293 bool discovery_is_atomic() const { return _discovery_is_atomic; } | |
| 294 void set_atomic_discovery(bool atomic) { _discovery_is_atomic = atomic; } | |
| 295 | |
| 296 // whether discovery is done by multiple threads same-old-timeously | |
| 297 bool discovery_is_mt() const { return _discovery_is_mt; } | |
| 298 void set_mt_discovery(bool mt) { _discovery_is_mt = mt; } | |
| 299 | |
| 300 // Whether we are in a phase when _processing_ is MT. | |
| 301 bool processing_is_mt() const { return _processing_is_mt; } | |
| 302 void set_mt_processing(bool mt) { _processing_is_mt = mt; } | |
| 303 | |
| 304 // whether all enqueuing of weak references is complete | |
| 305 bool enqueuing_is_done() { return _enqueuing_is_done; } | |
| 306 void set_enqueuing_is_done(bool v) { _enqueuing_is_done = v; } | |
| 307 | |
| 308 // iterate over oops | |
| 309 void weak_oops_do(OopClosure* f); // weak roots | |
| 310 static void oops_do(OopClosure* f); // strong root(s) | |
| 311 | |
| 312 // Discover a Reference object, using appropriate discovery criteria | |
| 313 bool discover_reference(oop obj, ReferenceType rt); | |
| 314 | |
| 315 // Process references found during GC (called by the garbage collector) | |
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316 void process_discovered_references(BoolObjectClosure* is_alive, |
| 0 | 317 OopClosure* keep_alive, |
| 318 VoidClosure* complete_gc, | |
| 319 AbstractRefProcTaskExecutor* task_executor); | |
| 320 | |
| 321 public: | |
| 322 // Enqueue references at end of GC (called by the garbage collector) | |
| 323 bool enqueue_discovered_references(AbstractRefProcTaskExecutor* task_executor = NULL); | |
| 324 | |
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325 // If a discovery is in process that is being superceded, abandon it: all |
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326 // the discovered lists will be empty, and all the objects on them will |
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327 // have NULL discovered fields. Must be called only at a safepoint. |
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328 void abandon_partial_discovery(); |
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329 |
| 0 | 330 // debugging |
| 331 void verify_no_references_recorded() PRODUCT_RETURN; | |
| 332 static void verify(); | |
| 333 | |
| 334 // clear the discovered lists (unlinking each entry). | |
| 335 void clear_discovered_references() PRODUCT_RETURN; | |
| 336 }; | |
| 337 | |
| 338 // A utility class to disable reference discovery in | |
| 339 // the scope which contains it, for given ReferenceProcessor. | |
| 340 class NoRefDiscovery: StackObj { | |
| 341 private: | |
| 342 ReferenceProcessor* _rp; | |
| 343 bool _was_discovering_refs; | |
| 344 public: | |
| 345 NoRefDiscovery(ReferenceProcessor* rp) : _rp(rp) { | |
| 346 if (_was_discovering_refs = _rp->discovery_enabled()) { | |
| 347 _rp->disable_discovery(); | |
| 348 } | |
| 349 } | |
| 350 | |
| 351 ~NoRefDiscovery() { | |
| 352 if (_was_discovering_refs) { | |
| 353 _rp->enable_discovery(); | |
| 354 } | |
| 355 } | |
| 356 }; | |
| 357 | |
| 358 | |
| 359 // A utility class to temporarily mutate the span of the | |
| 360 // given ReferenceProcessor in the scope that contains it. | |
| 361 class ReferenceProcessorSpanMutator: StackObj { | |
| 362 private: | |
| 363 ReferenceProcessor* _rp; | |
| 364 MemRegion _saved_span; | |
| 365 | |
| 366 public: | |
| 367 ReferenceProcessorSpanMutator(ReferenceProcessor* rp, | |
| 368 MemRegion span): | |
| 369 _rp(rp) { | |
| 370 _saved_span = _rp->span(); | |
| 371 _rp->set_span(span); | |
| 372 } | |
| 373 | |
| 374 ~ReferenceProcessorSpanMutator() { | |
| 375 _rp->set_span(_saved_span); | |
| 376 } | |
| 377 }; | |
| 378 | |
| 379 // A utility class to temporarily change the MT'ness of | |
| 380 // reference discovery for the given ReferenceProcessor | |
| 381 // in the scope that contains it. | |
| 382 class ReferenceProcessorMTMutator: StackObj { | |
| 383 private: | |
| 384 ReferenceProcessor* _rp; | |
| 385 bool _saved_mt; | |
| 386 | |
| 387 public: | |
| 388 ReferenceProcessorMTMutator(ReferenceProcessor* rp, | |
| 389 bool mt): | |
| 390 _rp(rp) { | |
| 391 _saved_mt = _rp->discovery_is_mt(); | |
| 392 _rp->set_mt_discovery(mt); | |
| 393 } | |
| 394 | |
| 395 ~ReferenceProcessorMTMutator() { | |
| 396 _rp->set_mt_discovery(_saved_mt); | |
| 397 } | |
| 398 }; | |
| 399 | |
| 400 | |
| 401 // A utility class to temporarily change the disposition | |
| 402 // of the "is_alive_non_header" closure field of the | |
| 403 // given ReferenceProcessor in the scope that contains it. | |
| 404 class ReferenceProcessorIsAliveMutator: StackObj { | |
| 405 private: | |
| 406 ReferenceProcessor* _rp; | |
| 407 BoolObjectClosure* _saved_cl; | |
| 408 | |
| 409 public: | |
| 410 ReferenceProcessorIsAliveMutator(ReferenceProcessor* rp, | |
| 411 BoolObjectClosure* cl): | |
| 412 _rp(rp) { | |
| 413 _saved_cl = _rp->is_alive_non_header(); | |
| 414 _rp->set_is_alive_non_header(cl); | |
| 415 } | |
| 416 | |
| 417 ~ReferenceProcessorIsAliveMutator() { | |
| 418 _rp->set_is_alive_non_header(_saved_cl); | |
| 419 } | |
| 420 }; | |
| 421 | |
| 422 // A utility class to temporarily change the disposition | |
| 423 // of the "discovery_is_atomic" field of the | |
| 424 // given ReferenceProcessor in the scope that contains it. | |
| 425 class ReferenceProcessorAtomicMutator: StackObj { | |
| 426 private: | |
| 427 ReferenceProcessor* _rp; | |
| 428 bool _saved_atomic_discovery; | |
| 429 | |
| 430 public: | |
| 431 ReferenceProcessorAtomicMutator(ReferenceProcessor* rp, | |
| 432 bool atomic): | |
| 433 _rp(rp) { | |
| 434 _saved_atomic_discovery = _rp->discovery_is_atomic(); | |
| 435 _rp->set_atomic_discovery(atomic); | |
| 436 } | |
| 437 | |
| 438 ~ReferenceProcessorAtomicMutator() { | |
| 439 _rp->set_atomic_discovery(_saved_atomic_discovery); | |
| 440 } | |
| 441 }; | |
| 442 | |
| 443 | |
| 444 // A utility class to temporarily change the MT processing | |
| 445 // disposition of the given ReferenceProcessor instance | |
| 446 // in the scope that contains it. | |
| 447 class ReferenceProcessorMTProcMutator: StackObj { | |
| 448 private: | |
| 449 ReferenceProcessor* _rp; | |
| 450 bool _saved_mt; | |
| 451 | |
| 452 public: | |
| 453 ReferenceProcessorMTProcMutator(ReferenceProcessor* rp, | |
| 454 bool mt): | |
| 455 _rp(rp) { | |
| 456 _saved_mt = _rp->processing_is_mt(); | |
| 457 _rp->set_mt_processing(mt); | |
| 458 } | |
| 459 | |
| 460 ~ReferenceProcessorMTProcMutator() { | |
| 461 _rp->set_mt_processing(_saved_mt); | |
| 462 } | |
| 463 }; | |
| 464 | |
| 465 | |
| 466 // This class is an interface used to implement task execution for the | |
| 467 // reference processing. | |
| 468 class AbstractRefProcTaskExecutor { | |
| 469 public: | |
| 470 | |
| 471 // Abstract tasks to execute. | |
| 472 class ProcessTask; | |
| 473 class EnqueueTask; | |
| 474 | |
| 475 // Executes a task using worker threads. | |
| 476 virtual void execute(ProcessTask& task) = 0; | |
| 477 virtual void execute(EnqueueTask& task) = 0; | |
| 478 | |
| 479 // Switch to single threaded mode. | |
| 480 virtual void set_single_threaded_mode() { }; | |
| 481 }; | |
| 482 | |
| 483 // Abstract reference processing task to execute. | |
| 484 class AbstractRefProcTaskExecutor::ProcessTask { | |
| 485 protected: | |
| 486 ProcessTask(ReferenceProcessor& ref_processor, | |
| 487 DiscoveredList refs_lists[], | |
| 488 bool marks_oops_alive) | |
| 489 : _ref_processor(ref_processor), | |
| 490 _refs_lists(refs_lists), | |
| 491 _marks_oops_alive(marks_oops_alive) | |
| 492 { } | |
| 493 | |
| 494 public: | |
| 495 virtual void work(unsigned int work_id, BoolObjectClosure& is_alive, | |
| 496 OopClosure& keep_alive, | |
| 497 VoidClosure& complete_gc) = 0; | |
| 498 | |
| 499 // Returns true if a task marks some oops as alive. | |
| 500 bool marks_oops_alive() const | |
| 501 { return _marks_oops_alive; } | |
| 502 | |
| 503 protected: | |
| 504 ReferenceProcessor& _ref_processor; | |
| 505 DiscoveredList* _refs_lists; | |
| 506 const bool _marks_oops_alive; | |
| 507 }; | |
| 508 | |
| 509 // Abstract reference processing task to execute. | |
| 510 class AbstractRefProcTaskExecutor::EnqueueTask { | |
| 511 protected: | |
| 512 EnqueueTask(ReferenceProcessor& ref_processor, | |
| 513 DiscoveredList refs_lists[], | |
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514 HeapWord* pending_list_addr, |
| 0 | 515 oop sentinel_ref, |
| 516 int n_queues) | |
| 517 : _ref_processor(ref_processor), | |
| 518 _refs_lists(refs_lists), | |
| 519 _pending_list_addr(pending_list_addr), | |
| 520 _sentinel_ref(sentinel_ref), | |
| 521 _n_queues(n_queues) | |
| 522 { } | |
| 523 | |
| 524 public: | |
| 525 virtual void work(unsigned int work_id) = 0; | |
| 526 | |
| 527 protected: | |
| 528 ReferenceProcessor& _ref_processor; | |
| 529 DiscoveredList* _refs_lists; | |
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530 HeapWord* _pending_list_addr; |
| 0 | 531 oop _sentinel_ref; |
| 532 int _n_queues; | |
| 533 }; |