src/share/vm/gc_implementation/g1/concurrentMark.hpp

Wed, 19 Aug 2009 12:53:25 -0400

author
tonyp
date
Wed, 19 Aug 2009 12:53:25 -0400
changeset 1371
e1fdf4fd34dc
parent 1280
df6caf649ff7
child 1454
035d2e036a9b
permissions
-rw-r--r--

6871111: G1: remove the concurrent overhead tracker
Summary: Removing the concurrent overhead tracker from G1, along with the GC overhead reporter and the G1AccountConcurrentOverhead (both of which rely on the the concurrent overhead tracker).
Reviewed-by: iveresov, johnc

ysr@777 1 /*
xdono@1014 2 * Copyright 2001-2009 Sun Microsystems, Inc. All Rights Reserved.
ysr@777 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
ysr@777 4 *
ysr@777 5 * This code is free software; you can redistribute it and/or modify it
ysr@777 6 * under the terms of the GNU General Public License version 2 only, as
ysr@777 7 * published by the Free Software Foundation.
ysr@777 8 *
ysr@777 9 * This code is distributed in the hope that it will be useful, but WITHOUT
ysr@777 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
ysr@777 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
ysr@777 12 * version 2 for more details (a copy is included in the LICENSE file that
ysr@777 13 * accompanied this code).
ysr@777 14 *
ysr@777 15 * You should have received a copy of the GNU General Public License version
ysr@777 16 * 2 along with this work; if not, write to the Free Software Foundation,
ysr@777 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
ysr@777 18 *
ysr@777 19 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
ysr@777 20 * CA 95054 USA or visit www.sun.com if you need additional information or
ysr@777 21 * have any questions.
ysr@777 22 *
ysr@777 23 */
ysr@777 24
ysr@777 25 class G1CollectedHeap;
ysr@777 26 class CMTask;
ysr@777 27 typedef GenericTaskQueue<oop> CMTaskQueue;
ysr@777 28 typedef GenericTaskQueueSet<oop> CMTaskQueueSet;
ysr@777 29
ysr@777 30 // A generic CM bit map. This is essentially a wrapper around the BitMap
ysr@777 31 // class, with one bit per (1<<_shifter) HeapWords.
ysr@777 32
apetrusenko@984 33 class CMBitMapRO VALUE_OBJ_CLASS_SPEC {
ysr@777 34 protected:
ysr@777 35 HeapWord* _bmStartWord; // base address of range covered by map
ysr@777 36 size_t _bmWordSize; // map size (in #HeapWords covered)
ysr@777 37 const int _shifter; // map to char or bit
ysr@777 38 VirtualSpace _virtual_space; // underlying the bit map
ysr@777 39 BitMap _bm; // the bit map itself
ysr@777 40
ysr@777 41 public:
ysr@777 42 // constructor
ysr@777 43 CMBitMapRO(ReservedSpace rs, int shifter);
ysr@777 44
ysr@777 45 enum { do_yield = true };
ysr@777 46
ysr@777 47 // inquiries
ysr@777 48 HeapWord* startWord() const { return _bmStartWord; }
ysr@777 49 size_t sizeInWords() const { return _bmWordSize; }
ysr@777 50 // the following is one past the last word in space
ysr@777 51 HeapWord* endWord() const { return _bmStartWord + _bmWordSize; }
ysr@777 52
ysr@777 53 // read marks
ysr@777 54
ysr@777 55 bool isMarked(HeapWord* addr) const {
ysr@777 56 assert(_bmStartWord <= addr && addr < (_bmStartWord + _bmWordSize),
ysr@777 57 "outside underlying space?");
ysr@777 58 return _bm.at(heapWordToOffset(addr));
ysr@777 59 }
ysr@777 60
ysr@777 61 // iteration
ysr@777 62 bool iterate(BitMapClosure* cl) { return _bm.iterate(cl); }
ysr@777 63 bool iterate(BitMapClosure* cl, MemRegion mr);
ysr@777 64
ysr@777 65 // Return the address corresponding to the next marked bit at or after
ysr@777 66 // "addr", and before "limit", if "limit" is non-NULL. If there is no
ysr@777 67 // such bit, returns "limit" if that is non-NULL, or else "endWord()".
ysr@777 68 HeapWord* getNextMarkedWordAddress(HeapWord* addr,
ysr@777 69 HeapWord* limit = NULL) const;
ysr@777 70 // Return the address corresponding to the next unmarked bit at or after
ysr@777 71 // "addr", and before "limit", if "limit" is non-NULL. If there is no
ysr@777 72 // such bit, returns "limit" if that is non-NULL, or else "endWord()".
ysr@777 73 HeapWord* getNextUnmarkedWordAddress(HeapWord* addr,
ysr@777 74 HeapWord* limit = NULL) const;
ysr@777 75
ysr@777 76 // conversion utilities
ysr@777 77 // XXX Fix these so that offsets are size_t's...
ysr@777 78 HeapWord* offsetToHeapWord(size_t offset) const {
ysr@777 79 return _bmStartWord + (offset << _shifter);
ysr@777 80 }
ysr@777 81 size_t heapWordToOffset(HeapWord* addr) const {
ysr@777 82 return pointer_delta(addr, _bmStartWord) >> _shifter;
ysr@777 83 }
ysr@777 84 int heapWordDiffToOffsetDiff(size_t diff) const;
ysr@777 85 HeapWord* nextWord(HeapWord* addr) {
ysr@777 86 return offsetToHeapWord(heapWordToOffset(addr) + 1);
ysr@777 87 }
ysr@777 88
ysr@777 89 void mostly_disjoint_range_union(BitMap* from_bitmap,
ysr@777 90 size_t from_start_index,
ysr@777 91 HeapWord* to_start_word,
ysr@777 92 size_t word_num);
ysr@777 93
ysr@777 94 // debugging
ysr@777 95 NOT_PRODUCT(bool covers(ReservedSpace rs) const;)
ysr@777 96 };
ysr@777 97
ysr@777 98 class CMBitMap : public CMBitMapRO {
ysr@777 99
ysr@777 100 public:
ysr@777 101 // constructor
ysr@777 102 CMBitMap(ReservedSpace rs, int shifter) :
ysr@777 103 CMBitMapRO(rs, shifter) {}
ysr@777 104
ysr@777 105 // write marks
ysr@777 106 void mark(HeapWord* addr) {
ysr@777 107 assert(_bmStartWord <= addr && addr < (_bmStartWord + _bmWordSize),
ysr@777 108 "outside underlying space?");
ysr@777 109 _bm.at_put(heapWordToOffset(addr), true);
ysr@777 110 }
ysr@777 111 void clear(HeapWord* addr) {
ysr@777 112 assert(_bmStartWord <= addr && addr < (_bmStartWord + _bmWordSize),
ysr@777 113 "outside underlying space?");
ysr@777 114 _bm.at_put(heapWordToOffset(addr), false);
ysr@777 115 }
ysr@777 116 bool parMark(HeapWord* addr) {
ysr@777 117 assert(_bmStartWord <= addr && addr < (_bmStartWord + _bmWordSize),
ysr@777 118 "outside underlying space?");
ysr@777 119 return _bm.par_at_put(heapWordToOffset(addr), true);
ysr@777 120 }
ysr@777 121 bool parClear(HeapWord* addr) {
ysr@777 122 assert(_bmStartWord <= addr && addr < (_bmStartWord + _bmWordSize),
ysr@777 123 "outside underlying space?");
ysr@777 124 return _bm.par_at_put(heapWordToOffset(addr), false);
ysr@777 125 }
ysr@777 126 void markRange(MemRegion mr);
ysr@777 127 void clearAll();
ysr@777 128 void clearRange(MemRegion mr);
ysr@777 129
ysr@777 130 // Starting at the bit corresponding to "addr" (inclusive), find the next
ysr@777 131 // "1" bit, if any. This bit starts some run of consecutive "1"'s; find
ysr@777 132 // the end of this run (stopping at "end_addr"). Return the MemRegion
ysr@777 133 // covering from the start of the region corresponding to the first bit
ysr@777 134 // of the run to the end of the region corresponding to the last bit of
ysr@777 135 // the run. If there is no "1" bit at or after "addr", return an empty
ysr@777 136 // MemRegion.
ysr@777 137 MemRegion getAndClearMarkedRegion(HeapWord* addr, HeapWord* end_addr);
ysr@777 138 };
ysr@777 139
ysr@777 140 // Represents a marking stack used by the CM collector.
ysr@777 141 // Ideally this should be GrowableArray<> just like MSC's marking stack(s).
apetrusenko@984 142 class CMMarkStack VALUE_OBJ_CLASS_SPEC {
ysr@777 143 ConcurrentMark* _cm;
ysr@777 144 oop* _base; // bottom of stack
ysr@777 145 jint _index; // one more than last occupied index
ysr@777 146 jint _capacity; // max #elements
ysr@777 147 jint _oops_do_bound; // Number of elements to include in next iteration.
ysr@777 148 NOT_PRODUCT(jint _max_depth;) // max depth plumbed during run
ysr@777 149
ysr@777 150 bool _overflow;
ysr@777 151 DEBUG_ONLY(bool _drain_in_progress;)
ysr@777 152 DEBUG_ONLY(bool _drain_in_progress_yields;)
ysr@777 153
ysr@777 154 public:
ysr@777 155 CMMarkStack(ConcurrentMark* cm);
ysr@777 156 ~CMMarkStack();
ysr@777 157
ysr@777 158 void allocate(size_t size);
ysr@777 159
ysr@777 160 oop pop() {
ysr@777 161 if (!isEmpty()) {
ysr@777 162 return _base[--_index] ;
ysr@777 163 }
ysr@777 164 return NULL;
ysr@777 165 }
ysr@777 166
ysr@777 167 // If overflow happens, don't do the push, and record the overflow.
ysr@777 168 // *Requires* that "ptr" is already marked.
ysr@777 169 void push(oop ptr) {
ysr@777 170 if (isFull()) {
ysr@777 171 // Record overflow.
ysr@777 172 _overflow = true;
ysr@777 173 return;
ysr@777 174 } else {
ysr@777 175 _base[_index++] = ptr;
ysr@777 176 NOT_PRODUCT(_max_depth = MAX2(_max_depth, _index));
ysr@777 177 }
ysr@777 178 }
ysr@777 179 // Non-block impl. Note: concurrency is allowed only with other
ysr@777 180 // "par_push" operations, not with "pop" or "drain". We would need
ysr@777 181 // parallel versions of them if such concurrency was desired.
ysr@777 182 void par_push(oop ptr);
ysr@777 183
ysr@777 184 // Pushes the first "n" elements of "ptr_arr" on the stack.
ysr@777 185 // Non-block impl. Note: concurrency is allowed only with other
ysr@777 186 // "par_adjoin_arr" or "push" operations, not with "pop" or "drain".
ysr@777 187 void par_adjoin_arr(oop* ptr_arr, int n);
ysr@777 188
ysr@777 189 // Pushes the first "n" elements of "ptr_arr" on the stack.
ysr@777 190 // Locking impl: concurrency is allowed only with
ysr@777 191 // "par_push_arr" and/or "par_pop_arr" operations, which use the same
ysr@777 192 // locking strategy.
ysr@777 193 void par_push_arr(oop* ptr_arr, int n);
ysr@777 194
ysr@777 195 // If returns false, the array was empty. Otherwise, removes up to "max"
ysr@777 196 // elements from the stack, and transfers them to "ptr_arr" in an
ysr@777 197 // unspecified order. The actual number transferred is given in "n" ("n
ysr@777 198 // == 0" is deliberately redundant with the return value.) Locking impl:
ysr@777 199 // concurrency is allowed only with "par_push_arr" and/or "par_pop_arr"
ysr@777 200 // operations, which use the same locking strategy.
ysr@777 201 bool par_pop_arr(oop* ptr_arr, int max, int* n);
ysr@777 202
ysr@777 203 // Drain the mark stack, applying the given closure to all fields of
ysr@777 204 // objects on the stack. (That is, continue until the stack is empty,
ysr@777 205 // even if closure applications add entries to the stack.) The "bm"
ysr@777 206 // argument, if non-null, may be used to verify that only marked objects
ysr@777 207 // are on the mark stack. If "yield_after" is "true", then the
ysr@777 208 // concurrent marker performing the drain offers to yield after
ysr@777 209 // processing each object. If a yield occurs, stops the drain operation
ysr@777 210 // and returns false. Otherwise, returns true.
ysr@777 211 template<class OopClosureClass>
ysr@777 212 bool drain(OopClosureClass* cl, CMBitMap* bm, bool yield_after = false);
ysr@777 213
ysr@777 214 bool isEmpty() { return _index == 0; }
ysr@777 215 bool isFull() { return _index == _capacity; }
ysr@777 216 int maxElems() { return _capacity; }
ysr@777 217
ysr@777 218 bool overflow() { return _overflow; }
ysr@777 219 void clear_overflow() { _overflow = false; }
ysr@777 220
ysr@777 221 int size() { return _index; }
ysr@777 222
ysr@777 223 void setEmpty() { _index = 0; clear_overflow(); }
ysr@777 224
ysr@777 225 // Record the current size; a subsequent "oops_do" will iterate only over
ysr@777 226 // indices valid at the time of this call.
ysr@777 227 void set_oops_do_bound(jint bound = -1) {
ysr@777 228 if (bound == -1) {
ysr@777 229 _oops_do_bound = _index;
ysr@777 230 } else {
ysr@777 231 _oops_do_bound = bound;
ysr@777 232 }
ysr@777 233 }
ysr@777 234 jint oops_do_bound() { return _oops_do_bound; }
ysr@777 235 // iterate over the oops in the mark stack, up to the bound recorded via
ysr@777 236 // the call above.
ysr@777 237 void oops_do(OopClosure* f);
ysr@777 238 };
ysr@777 239
apetrusenko@984 240 class CMRegionStack VALUE_OBJ_CLASS_SPEC {
ysr@777 241 MemRegion* _base;
ysr@777 242 jint _capacity;
ysr@777 243 jint _index;
ysr@777 244 jint _oops_do_bound;
ysr@777 245 bool _overflow;
ysr@777 246 public:
ysr@777 247 CMRegionStack();
ysr@777 248 ~CMRegionStack();
ysr@777 249 void allocate(size_t size);
ysr@777 250
ysr@777 251 // This is lock-free; assumes that it will only be called in parallel
ysr@777 252 // with other "push" operations (no pops).
ysr@777 253 void push(MemRegion mr);
ysr@777 254
ysr@777 255 // Lock-free; assumes that it will only be called in parallel
ysr@777 256 // with other "pop" operations (no pushes).
ysr@777 257 MemRegion pop();
ysr@777 258
ysr@777 259 bool isEmpty() { return _index == 0; }
ysr@777 260 bool isFull() { return _index == _capacity; }
ysr@777 261
ysr@777 262 bool overflow() { return _overflow; }
ysr@777 263 void clear_overflow() { _overflow = false; }
ysr@777 264
ysr@777 265 int size() { return _index; }
ysr@777 266
ysr@777 267 // It iterates over the entries in the region stack and it
ysr@777 268 // invalidates (i.e. assigns MemRegion()) the ones that point to
ysr@777 269 // regions in the collection set.
ysr@777 270 bool invalidate_entries_into_cset();
ysr@777 271
ysr@777 272 // This gives an upper bound up to which the iteration in
ysr@777 273 // invalidate_entries_into_cset() will reach. This prevents
ysr@777 274 // newly-added entries to be unnecessarily scanned.
ysr@777 275 void set_oops_do_bound() {
ysr@777 276 _oops_do_bound = _index;
ysr@777 277 }
ysr@777 278
ysr@777 279 void setEmpty() { _index = 0; clear_overflow(); }
ysr@777 280 };
ysr@777 281
ysr@777 282 // this will enable a variety of different statistics per GC task
ysr@777 283 #define _MARKING_STATS_ 0
ysr@777 284 // this will enable the higher verbose levels
ysr@777 285 #define _MARKING_VERBOSE_ 0
ysr@777 286
ysr@777 287 #if _MARKING_STATS_
ysr@777 288 #define statsOnly(statement) \
ysr@777 289 do { \
ysr@777 290 statement ; \
ysr@777 291 } while (0)
ysr@777 292 #else // _MARKING_STATS_
ysr@777 293 #define statsOnly(statement) \
ysr@777 294 do { \
ysr@777 295 } while (0)
ysr@777 296 #endif // _MARKING_STATS_
ysr@777 297
ysr@777 298 // Some extra guarantees that I like to also enable in optimised mode
ysr@777 299 // when debugging. If you want to enable them, comment out the assert
ysr@777 300 // macro and uncomment out the guaratee macro
ysr@777 301 // #define tmp_guarantee_CM(expr, str) guarantee(expr, str)
ysr@777 302 #define tmp_guarantee_CM(expr, str) assert(expr, str)
ysr@777 303
ysr@777 304 typedef enum {
ysr@777 305 no_verbose = 0, // verbose turned off
ysr@777 306 stats_verbose, // only prints stats at the end of marking
ysr@777 307 low_verbose, // low verbose, mostly per region and per major event
ysr@777 308 medium_verbose, // a bit more detailed than low
ysr@777 309 high_verbose // per object verbose
ysr@777 310 } CMVerboseLevel;
ysr@777 311
ysr@777 312
ysr@777 313 class ConcurrentMarkThread;
ysr@777 314
apetrusenko@984 315 class ConcurrentMark: public CHeapObj {
ysr@777 316 friend class ConcurrentMarkThread;
ysr@777 317 friend class CMTask;
ysr@777 318 friend class CMBitMapClosure;
ysr@777 319 friend class CSMarkOopClosure;
ysr@777 320 friend class CMGlobalObjectClosure;
ysr@777 321 friend class CMRemarkTask;
ysr@777 322 friend class CMConcurrentMarkingTask;
ysr@777 323 friend class G1ParNoteEndTask;
ysr@777 324 friend class CalcLiveObjectsClosure;
ysr@777 325
ysr@777 326 protected:
ysr@777 327 ConcurrentMarkThread* _cmThread; // the thread doing the work
ysr@777 328 G1CollectedHeap* _g1h; // the heap.
ysr@777 329 size_t _parallel_marking_threads; // the number of marking
ysr@777 330 // threads we'll use
ysr@777 331 double _sleep_factor; // how much we have to sleep, with
ysr@777 332 // respect to the work we just did, to
ysr@777 333 // meet the marking overhead goal
ysr@777 334 double _marking_task_overhead; // marking target overhead for
ysr@777 335 // a single task
ysr@777 336
ysr@777 337 // same as the two above, but for the cleanup task
ysr@777 338 double _cleanup_sleep_factor;
ysr@777 339 double _cleanup_task_overhead;
ysr@777 340
ysr@777 341 // Stuff related to age cohort processing.
ysr@777 342 struct ParCleanupThreadState {
ysr@777 343 char _pre[64];
ysr@777 344 UncleanRegionList list;
ysr@777 345 char _post[64];
ysr@777 346 };
ysr@777 347 ParCleanupThreadState** _par_cleanup_thread_state;
ysr@777 348
ysr@777 349 // CMS marking support structures
ysr@777 350 CMBitMap _markBitMap1;
ysr@777 351 CMBitMap _markBitMap2;
ysr@777 352 CMBitMapRO* _prevMarkBitMap; // completed mark bitmap
ysr@777 353 CMBitMap* _nextMarkBitMap; // under-construction mark bitmap
ysr@777 354 bool _at_least_one_mark_complete;
ysr@777 355
ysr@777 356 BitMap _region_bm;
ysr@777 357 BitMap _card_bm;
ysr@777 358
ysr@777 359 // Heap bounds
ysr@777 360 HeapWord* _heap_start;
ysr@777 361 HeapWord* _heap_end;
ysr@777 362
ysr@777 363 // For gray objects
ysr@777 364 CMMarkStack _markStack; // Grey objects behind global finger.
ysr@777 365 CMRegionStack _regionStack; // Grey regions behind global finger.
ysr@777 366 HeapWord* volatile _finger; // the global finger, region aligned,
ysr@777 367 // always points to the end of the
ysr@777 368 // last claimed region
ysr@777 369
ysr@777 370 // marking tasks
ysr@777 371 size_t _max_task_num; // maximum task number
ysr@777 372 size_t _active_tasks; // task num currently active
ysr@777 373 CMTask** _tasks; // task queue array (max_task_num len)
ysr@777 374 CMTaskQueueSet* _task_queues; // task queue set
ysr@777 375 ParallelTaskTerminator _terminator; // for termination
ysr@777 376
ysr@777 377 // Two sync barriers that are used to synchronise tasks when an
ysr@777 378 // overflow occurs. The algorithm is the following. All tasks enter
ysr@777 379 // the first one to ensure that they have all stopped manipulating
ysr@777 380 // the global data structures. After they exit it, they re-initialise
ysr@777 381 // their data structures and task 0 re-initialises the global data
ysr@777 382 // structures. Then, they enter the second sync barrier. This
ysr@777 383 // ensure, that no task starts doing work before all data
ysr@777 384 // structures (local and global) have been re-initialised. When they
ysr@777 385 // exit it, they are free to start working again.
ysr@777 386 WorkGangBarrierSync _first_overflow_barrier_sync;
ysr@777 387 WorkGangBarrierSync _second_overflow_barrier_sync;
ysr@777 388
ysr@777 389
ysr@777 390 // this is set by any task, when an overflow on the global data
ysr@777 391 // structures is detected.
ysr@777 392 volatile bool _has_overflown;
ysr@777 393 // true: marking is concurrent, false: we're in remark
ysr@777 394 volatile bool _concurrent;
ysr@777 395 // set at the end of a Full GC so that marking aborts
ysr@777 396 volatile bool _has_aborted;
ysr@777 397 // used when remark aborts due to an overflow to indicate that
ysr@777 398 // another concurrent marking phase should start
ysr@777 399 volatile bool _restart_for_overflow;
ysr@777 400
ysr@777 401 // This is true from the very start of concurrent marking until the
ysr@777 402 // point when all the tasks complete their work. It is really used
ysr@777 403 // to determine the points between the end of concurrent marking and
ysr@777 404 // time of remark.
ysr@777 405 volatile bool _concurrent_marking_in_progress;
ysr@777 406
ysr@777 407 // verbose level
ysr@777 408 CMVerboseLevel _verbose_level;
ysr@777 409
ysr@777 410 // These two fields are used to implement the optimisation that
ysr@777 411 // avoids pushing objects on the global/region stack if there are
ysr@777 412 // no collection set regions above the lowest finger.
ysr@777 413
ysr@777 414 // This is the lowest finger (among the global and local fingers),
ysr@777 415 // which is calculated before a new collection set is chosen.
ysr@777 416 HeapWord* _min_finger;
ysr@777 417 // If this flag is true, objects/regions that are marked below the
ysr@777 418 // finger should be pushed on the stack(s). If this is flag is
ysr@777 419 // false, it is safe not to push them on the stack(s).
ysr@777 420 bool _should_gray_objects;
ysr@777 421
ysr@777 422 // All of these times are in ms.
ysr@777 423 NumberSeq _init_times;
ysr@777 424 NumberSeq _remark_times;
ysr@777 425 NumberSeq _remark_mark_times;
ysr@777 426 NumberSeq _remark_weak_ref_times;
ysr@777 427 NumberSeq _cleanup_times;
ysr@777 428 double _total_counting_time;
ysr@777 429 double _total_rs_scrub_time;
ysr@777 430
ysr@777 431 double* _accum_task_vtime; // accumulated task vtime
ysr@777 432
ysr@777 433 WorkGang* _parallel_workers;
ysr@777 434
ysr@777 435 void weakRefsWork(bool clear_all_soft_refs);
ysr@777 436
ysr@777 437 void swapMarkBitMaps();
ysr@777 438
ysr@777 439 // It resets the global marking data structures, as well as the
ysr@777 440 // task local ones; should be called during initial mark.
ysr@777 441 void reset();
ysr@777 442 // It resets all the marking data structures.
ysr@777 443 void clear_marking_state();
ysr@777 444
ysr@777 445 // It should be called to indicate which phase we're in (concurrent
ysr@777 446 // mark or remark) and how many threads are currently active.
ysr@777 447 void set_phase(size_t active_tasks, bool concurrent);
ysr@777 448 // We do this after we're done with marking so that the marking data
ysr@777 449 // structures are initialised to a sensible and predictable state.
ysr@777 450 void set_non_marking_state();
ysr@777 451
ysr@777 452 // prints all gathered CM-related statistics
ysr@777 453 void print_stats();
ysr@777 454
ysr@777 455 // accessor methods
ysr@777 456 size_t parallel_marking_threads() { return _parallel_marking_threads; }
ysr@777 457 double sleep_factor() { return _sleep_factor; }
ysr@777 458 double marking_task_overhead() { return _marking_task_overhead;}
ysr@777 459 double cleanup_sleep_factor() { return _cleanup_sleep_factor; }
ysr@777 460 double cleanup_task_overhead() { return _cleanup_task_overhead;}
ysr@777 461
ysr@777 462 HeapWord* finger() { return _finger; }
ysr@777 463 bool concurrent() { return _concurrent; }
ysr@777 464 size_t active_tasks() { return _active_tasks; }
ysr@777 465 ParallelTaskTerminator* terminator() { return &_terminator; }
ysr@777 466
ysr@777 467 // It claims the next available region to be scanned by a marking
ysr@777 468 // task. It might return NULL if the next region is empty or we have
ysr@777 469 // run out of regions. In the latter case, out_of_regions()
ysr@777 470 // determines whether we've really run out of regions or the task
ysr@777 471 // should call claim_region() again. This might seem a bit
ysr@777 472 // awkward. Originally, the code was written so that claim_region()
ysr@777 473 // either successfully returned with a non-empty region or there
ysr@777 474 // were no more regions to be claimed. The problem with this was
ysr@777 475 // that, in certain circumstances, it iterated over large chunks of
ysr@777 476 // the heap finding only empty regions and, while it was working, it
ysr@777 477 // was preventing the calling task to call its regular clock
ysr@777 478 // method. So, this way, each task will spend very little time in
ysr@777 479 // claim_region() and is allowed to call the regular clock method
ysr@777 480 // frequently.
ysr@777 481 HeapRegion* claim_region(int task);
ysr@777 482
ysr@777 483 // It determines whether we've run out of regions to scan.
ysr@777 484 bool out_of_regions() { return _finger == _heap_end; }
ysr@777 485
ysr@777 486 // Returns the task with the given id
ysr@777 487 CMTask* task(int id) {
ysr@777 488 guarantee( 0 <= id && id < (int) _active_tasks, "task id not within "
ysr@777 489 "active bounds" );
ysr@777 490 return _tasks[id];
ysr@777 491 }
ysr@777 492
ysr@777 493 // Returns the task queue with the given id
ysr@777 494 CMTaskQueue* task_queue(int id) {
ysr@777 495 guarantee( 0 <= id && id < (int) _active_tasks, "task queue id not within "
ysr@777 496 "active bounds" );
ysr@777 497 return (CMTaskQueue*) _task_queues->queue(id);
ysr@777 498 }
ysr@777 499
ysr@777 500 // Returns the task queue set
ysr@777 501 CMTaskQueueSet* task_queues() { return _task_queues; }
ysr@777 502
ysr@777 503 // Access / manipulation of the overflow flag which is set to
ysr@777 504 // indicate that the global stack or region stack has overflown
ysr@777 505 bool has_overflown() { return _has_overflown; }
ysr@777 506 void set_has_overflown() { _has_overflown = true; }
ysr@777 507 void clear_has_overflown() { _has_overflown = false; }
ysr@777 508
ysr@777 509 bool has_aborted() { return _has_aborted; }
ysr@777 510 bool restart_for_overflow() { return _restart_for_overflow; }
ysr@777 511
ysr@777 512 // Methods to enter the two overflow sync barriers
ysr@777 513 void enter_first_sync_barrier(int task_num);
ysr@777 514 void enter_second_sync_barrier(int task_num);
ysr@777 515
ysr@777 516 public:
ysr@777 517 // Manipulation of the global mark stack.
ysr@777 518 // Notice that the first mark_stack_push is CAS-based, whereas the
ysr@777 519 // two below are Mutex-based. This is OK since the first one is only
ysr@777 520 // called during evacuation pauses and doesn't compete with the
ysr@777 521 // other two (which are called by the marking tasks during
ysr@777 522 // concurrent marking or remark).
ysr@777 523 bool mark_stack_push(oop p) {
ysr@777 524 _markStack.par_push(p);
ysr@777 525 if (_markStack.overflow()) {
ysr@777 526 set_has_overflown();
ysr@777 527 return false;
ysr@777 528 }
ysr@777 529 return true;
ysr@777 530 }
ysr@777 531 bool mark_stack_push(oop* arr, int n) {
ysr@777 532 _markStack.par_push_arr(arr, n);
ysr@777 533 if (_markStack.overflow()) {
ysr@777 534 set_has_overflown();
ysr@777 535 return false;
ysr@777 536 }
ysr@777 537 return true;
ysr@777 538 }
ysr@777 539 void mark_stack_pop(oop* arr, int max, int* n) {
ysr@777 540 _markStack.par_pop_arr(arr, max, n);
ysr@777 541 }
ysr@777 542 size_t mark_stack_size() { return _markStack.size(); }
ysr@777 543 size_t partial_mark_stack_size_target() { return _markStack.maxElems()/3; }
ysr@777 544 bool mark_stack_overflow() { return _markStack.overflow(); }
ysr@777 545 bool mark_stack_empty() { return _markStack.isEmpty(); }
ysr@777 546
ysr@777 547 // Manipulation of the region stack
ysr@777 548 bool region_stack_push(MemRegion mr) {
ysr@777 549 _regionStack.push(mr);
ysr@777 550 if (_regionStack.overflow()) {
ysr@777 551 set_has_overflown();
ysr@777 552 return false;
ysr@777 553 }
ysr@777 554 return true;
ysr@777 555 }
ysr@777 556 MemRegion region_stack_pop() { return _regionStack.pop(); }
ysr@777 557 int region_stack_size() { return _regionStack.size(); }
ysr@777 558 bool region_stack_overflow() { return _regionStack.overflow(); }
ysr@777 559 bool region_stack_empty() { return _regionStack.isEmpty(); }
ysr@777 560
ysr@777 561 bool concurrent_marking_in_progress() {
ysr@777 562 return _concurrent_marking_in_progress;
ysr@777 563 }
ysr@777 564 void set_concurrent_marking_in_progress() {
ysr@777 565 _concurrent_marking_in_progress = true;
ysr@777 566 }
ysr@777 567 void clear_concurrent_marking_in_progress() {
ysr@777 568 _concurrent_marking_in_progress = false;
ysr@777 569 }
ysr@777 570
ysr@777 571 void update_accum_task_vtime(int i, double vtime) {
ysr@777 572 _accum_task_vtime[i] += vtime;
ysr@777 573 }
ysr@777 574
ysr@777 575 double all_task_accum_vtime() {
ysr@777 576 double ret = 0.0;
ysr@777 577 for (int i = 0; i < (int)_max_task_num; ++i)
ysr@777 578 ret += _accum_task_vtime[i];
ysr@777 579 return ret;
ysr@777 580 }
ysr@777 581
ysr@777 582 // Attempts to steal an object from the task queues of other tasks
ysr@777 583 bool try_stealing(int task_num, int* hash_seed, oop& obj) {
ysr@777 584 return _task_queues->steal(task_num, hash_seed, obj);
ysr@777 585 }
ysr@777 586
ysr@777 587 // It grays an object by first marking it. Then, if it's behind the
ysr@777 588 // global finger, it also pushes it on the global stack.
ysr@777 589 void deal_with_reference(oop obj);
ysr@777 590
ysr@777 591 ConcurrentMark(ReservedSpace rs, int max_regions);
ysr@777 592 ~ConcurrentMark();
ysr@777 593 ConcurrentMarkThread* cmThread() { return _cmThread; }
ysr@777 594
ysr@777 595 CMBitMapRO* prevMarkBitMap() const { return _prevMarkBitMap; }
ysr@777 596 CMBitMap* nextMarkBitMap() const { return _nextMarkBitMap; }
ysr@777 597
ysr@777 598 // The following three are interaction between CM and
ysr@777 599 // G1CollectedHeap
ysr@777 600
ysr@777 601 // This notifies CM that a root during initial-mark needs to be
ysr@777 602 // grayed and it's MT-safe. Currently, we just mark it. But, in the
ysr@777 603 // future, we can experiment with pushing it on the stack and we can
ysr@777 604 // do this without changing G1CollectedHeap.
ysr@777 605 void grayRoot(oop p);
ysr@777 606 // It's used during evacuation pauses to gray a region, if
ysr@777 607 // necessary, and it's MT-safe. It assumes that the caller has
ysr@777 608 // marked any objects on that region. If _should_gray_objects is
ysr@777 609 // true and we're still doing concurrent marking, the region is
ysr@777 610 // pushed on the region stack, if it is located below the global
ysr@777 611 // finger, otherwise we do nothing.
ysr@777 612 void grayRegionIfNecessary(MemRegion mr);
ysr@777 613 // It's used during evacuation pauses to mark and, if necessary,
ysr@777 614 // gray a single object and it's MT-safe. It assumes the caller did
ysr@777 615 // not mark the object. If _should_gray_objects is true and we're
ysr@777 616 // still doing concurrent marking, the objects is pushed on the
ysr@777 617 // global stack, if it is located below the global finger, otherwise
ysr@777 618 // we do nothing.
ysr@777 619 void markAndGrayObjectIfNecessary(oop p);
ysr@777 620
ysr@777 621 // This iterates over the bitmap of the previous marking and prints
ysr@777 622 // out all objects that are marked on the bitmap and indicates
ysr@777 623 // whether what they point to is also marked or not.
ysr@777 624 void print_prev_bitmap_reachable();
ysr@777 625
ysr@777 626 // Clear the next marking bitmap (will be called concurrently).
ysr@777 627 void clearNextBitmap();
ysr@777 628
ysr@777 629 // main CMS steps and related support
ysr@777 630 void checkpointRootsInitial();
ysr@777 631
ysr@777 632 // These two do the work that needs to be done before and after the
ysr@777 633 // initial root checkpoint. Since this checkpoint can be done at two
ysr@777 634 // different points (i.e. an explicit pause or piggy-backed on a
ysr@777 635 // young collection), then it's nice to be able to easily share the
ysr@777 636 // pre/post code. It might be the case that we can put everything in
ysr@777 637 // the post method. TP
ysr@777 638 void checkpointRootsInitialPre();
ysr@777 639 void checkpointRootsInitialPost();
ysr@777 640
ysr@777 641 // Do concurrent phase of marking, to a tentative transitive closure.
ysr@777 642 void markFromRoots();
ysr@777 643
ysr@777 644 // Process all unprocessed SATB buffers. It is called at the
ysr@777 645 // beginning of an evacuation pause.
ysr@777 646 void drainAllSATBBuffers();
ysr@777 647
ysr@777 648 void checkpointRootsFinal(bool clear_all_soft_refs);
ysr@777 649 void checkpointRootsFinalWork();
ysr@777 650 void calcDesiredRegions();
ysr@777 651 void cleanup();
ysr@777 652 void completeCleanup();
ysr@777 653
ysr@777 654 // Mark in the previous bitmap. NB: this is usually read-only, so use
ysr@777 655 // this carefully!
ysr@777 656 void markPrev(oop p);
ysr@777 657 void clear(oop p);
ysr@777 658 // Clears marks for all objects in the given range, for both prev and
ysr@777 659 // next bitmaps. NB: the previous bitmap is usually read-only, so use
ysr@777 660 // this carefully!
ysr@777 661 void clearRangeBothMaps(MemRegion mr);
ysr@777 662
ysr@777 663 // Record the current top of the mark and region stacks; a
ysr@777 664 // subsequent oops_do() on the mark stack and
ysr@777 665 // invalidate_entries_into_cset() on the region stack will iterate
ysr@777 666 // only over indices valid at the time of this call.
ysr@777 667 void set_oops_do_bound() {
ysr@777 668 _markStack.set_oops_do_bound();
ysr@777 669 _regionStack.set_oops_do_bound();
ysr@777 670 }
ysr@777 671 // Iterate over the oops in the mark stack and all local queues. It
ysr@777 672 // also calls invalidate_entries_into_cset() on the region stack.
ysr@777 673 void oops_do(OopClosure* f);
ysr@777 674 // It is called at the end of an evacuation pause during marking so
ysr@777 675 // that CM is notified of where the new end of the heap is. It
ysr@777 676 // doesn't do anything if concurrent_marking_in_progress() is false,
ysr@777 677 // unless the force parameter is true.
ysr@777 678 void update_g1_committed(bool force = false);
ysr@777 679
ysr@777 680 void complete_marking_in_collection_set();
ysr@777 681
ysr@777 682 // It indicates that a new collection set is being chosen.
ysr@777 683 void newCSet();
ysr@777 684 // It registers a collection set heap region with CM. This is used
ysr@777 685 // to determine whether any heap regions are located above the finger.
ysr@777 686 void registerCSetRegion(HeapRegion* hr);
ysr@777 687
ysr@777 688 // Returns "true" if at least one mark has been completed.
ysr@777 689 bool at_least_one_mark_complete() { return _at_least_one_mark_complete; }
ysr@777 690
ysr@777 691 bool isMarked(oop p) const {
ysr@777 692 assert(p != NULL && p->is_oop(), "expected an oop");
ysr@777 693 HeapWord* addr = (HeapWord*)p;
ysr@777 694 assert(addr >= _nextMarkBitMap->startWord() ||
ysr@777 695 addr < _nextMarkBitMap->endWord(), "in a region");
ysr@777 696
ysr@777 697 return _nextMarkBitMap->isMarked(addr);
ysr@777 698 }
ysr@777 699
ysr@777 700 inline bool not_yet_marked(oop p) const;
ysr@777 701
ysr@777 702 // XXX Debug code
ysr@777 703 bool containing_card_is_marked(void* p);
ysr@777 704 bool containing_cards_are_marked(void* start, void* last);
ysr@777 705
ysr@777 706 bool isPrevMarked(oop p) const {
ysr@777 707 assert(p != NULL && p->is_oop(), "expected an oop");
ysr@777 708 HeapWord* addr = (HeapWord*)p;
ysr@777 709 assert(addr >= _prevMarkBitMap->startWord() ||
ysr@777 710 addr < _prevMarkBitMap->endWord(), "in a region");
ysr@777 711
ysr@777 712 return _prevMarkBitMap->isMarked(addr);
ysr@777 713 }
ysr@777 714
ysr@777 715 inline bool do_yield_check(int worker_i = 0);
ysr@777 716 inline bool should_yield();
ysr@777 717
ysr@777 718 // Called to abort the marking cycle after a Full GC takes palce.
ysr@777 719 void abort();
ysr@777 720
ysr@777 721 // This prints the global/local fingers. It is used for debugging.
ysr@777 722 NOT_PRODUCT(void print_finger();)
ysr@777 723
ysr@777 724 void print_summary_info();
ysr@777 725
ysr@777 726 // The following indicate whether a given verbose level has been
ysr@777 727 // set. Notice that anything above stats is conditional to
ysr@777 728 // _MARKING_VERBOSE_ having been set to 1
ysr@777 729 bool verbose_stats()
ysr@777 730 { return _verbose_level >= stats_verbose; }
ysr@777 731 bool verbose_low()
ysr@777 732 { return _MARKING_VERBOSE_ && _verbose_level >= low_verbose; }
ysr@777 733 bool verbose_medium()
ysr@777 734 { return _MARKING_VERBOSE_ && _verbose_level >= medium_verbose; }
ysr@777 735 bool verbose_high()
ysr@777 736 { return _MARKING_VERBOSE_ && _verbose_level >= high_verbose; }
ysr@777 737 };
ysr@777 738
ysr@777 739 // A class representing a marking task.
ysr@777 740 class CMTask : public TerminatorTerminator {
ysr@777 741 private:
ysr@777 742 enum PrivateConstants {
ysr@777 743 // the regular clock call is called once the scanned words reaches
ysr@777 744 // this limit
ysr@777 745 words_scanned_period = 12*1024,
ysr@777 746 // the regular clock call is called once the number of visited
ysr@777 747 // references reaches this limit
ysr@777 748 refs_reached_period = 384,
ysr@777 749 // initial value for the hash seed, used in the work stealing code
ysr@777 750 init_hash_seed = 17,
ysr@777 751 // how many entries will be transferred between global stack and
ysr@777 752 // local queues
ysr@777 753 global_stack_transfer_size = 16
ysr@777 754 };
ysr@777 755
ysr@777 756 int _task_id;
ysr@777 757 G1CollectedHeap* _g1h;
ysr@777 758 ConcurrentMark* _cm;
ysr@777 759 CMBitMap* _nextMarkBitMap;
ysr@777 760 // the task queue of this task
ysr@777 761 CMTaskQueue* _task_queue;
ysr@1280 762 private:
ysr@777 763 // the task queue set---needed for stealing
ysr@777 764 CMTaskQueueSet* _task_queues;
ysr@777 765 // indicates whether the task has been claimed---this is only for
ysr@777 766 // debugging purposes
ysr@777 767 bool _claimed;
ysr@777 768
ysr@777 769 // number of calls to this task
ysr@777 770 int _calls;
ysr@777 771
ysr@777 772 // when the virtual timer reaches this time, the marking step should
ysr@777 773 // exit
ysr@777 774 double _time_target_ms;
ysr@777 775 // the start time of the current marking step
ysr@777 776 double _start_time_ms;
ysr@777 777
ysr@777 778 // the oop closure used for iterations over oops
ysr@777 779 OopClosure* _oop_closure;
ysr@777 780
ysr@777 781 // the region this task is scanning, NULL if we're not scanning any
ysr@777 782 HeapRegion* _curr_region;
ysr@777 783 // the local finger of this task, NULL if we're not scanning a region
ysr@777 784 HeapWord* _finger;
ysr@777 785 // limit of the region this task is scanning, NULL if we're not scanning one
ysr@777 786 HeapWord* _region_limit;
ysr@777 787
ysr@777 788 // This is used only when we scan regions popped from the region
ysr@777 789 // stack. It records what the last object on such a region we
ysr@777 790 // scanned was. It is used to ensure that, if we abort region
ysr@777 791 // iteration, we do not rescan the first part of the region. This
ysr@777 792 // should be NULL when we're not scanning a region from the region
ysr@777 793 // stack.
ysr@777 794 HeapWord* _region_finger;
ysr@777 795
ysr@777 796 // the number of words this task has scanned
ysr@777 797 size_t _words_scanned;
ysr@777 798 // When _words_scanned reaches this limit, the regular clock is
ysr@777 799 // called. Notice that this might be decreased under certain
ysr@777 800 // circumstances (i.e. when we believe that we did an expensive
ysr@777 801 // operation).
ysr@777 802 size_t _words_scanned_limit;
ysr@777 803 // the initial value of _words_scanned_limit (i.e. what it was
ysr@777 804 // before it was decreased).
ysr@777 805 size_t _real_words_scanned_limit;
ysr@777 806
ysr@777 807 // the number of references this task has visited
ysr@777 808 size_t _refs_reached;
ysr@777 809 // When _refs_reached reaches this limit, the regular clock is
ysr@777 810 // called. Notice this this might be decreased under certain
ysr@777 811 // circumstances (i.e. when we believe that we did an expensive
ysr@777 812 // operation).
ysr@777 813 size_t _refs_reached_limit;
ysr@777 814 // the initial value of _refs_reached_limit (i.e. what it was before
ysr@777 815 // it was decreased).
ysr@777 816 size_t _real_refs_reached_limit;
ysr@777 817
ysr@777 818 // used by the work stealing stuff
ysr@777 819 int _hash_seed;
ysr@777 820 // if this is true, then the task has aborted for some reason
ysr@777 821 bool _has_aborted;
ysr@777 822 // set when the task aborts because it has met its time quota
ysr@777 823 bool _has_aborted_timed_out;
ysr@777 824 // true when we're draining SATB buffers; this avoids the task
ysr@777 825 // aborting due to SATB buffers being available (as we're already
ysr@777 826 // dealing with them)
ysr@777 827 bool _draining_satb_buffers;
ysr@777 828
ysr@777 829 // number sequence of past step times
ysr@777 830 NumberSeq _step_times_ms;
ysr@777 831 // elapsed time of this task
ysr@777 832 double _elapsed_time_ms;
ysr@777 833 // termination time of this task
ysr@777 834 double _termination_time_ms;
ysr@777 835 // when this task got into the termination protocol
ysr@777 836 double _termination_start_time_ms;
ysr@777 837
ysr@777 838 // true when the task is during a concurrent phase, false when it is
ysr@777 839 // in the remark phase (so, in the latter case, we do not have to
ysr@777 840 // check all the things that we have to check during the concurrent
ysr@777 841 // phase, i.e. SATB buffer availability...)
ysr@777 842 bool _concurrent;
ysr@777 843
ysr@777 844 TruncatedSeq _marking_step_diffs_ms;
ysr@777 845
ysr@777 846 // LOTS of statistics related with this task
ysr@777 847 #if _MARKING_STATS_
ysr@777 848 NumberSeq _all_clock_intervals_ms;
ysr@777 849 double _interval_start_time_ms;
ysr@777 850
ysr@777 851 int _aborted;
ysr@777 852 int _aborted_overflow;
ysr@777 853 int _aborted_cm_aborted;
ysr@777 854 int _aborted_yield;
ysr@777 855 int _aborted_timed_out;
ysr@777 856 int _aborted_satb;
ysr@777 857 int _aborted_termination;
ysr@777 858
ysr@777 859 int _steal_attempts;
ysr@777 860 int _steals;
ysr@777 861
ysr@777 862 int _clock_due_to_marking;
ysr@777 863 int _clock_due_to_scanning;
ysr@777 864
ysr@777 865 int _local_pushes;
ysr@777 866 int _local_pops;
ysr@777 867 int _local_max_size;
ysr@777 868 int _objs_scanned;
ysr@777 869
ysr@777 870 int _global_pushes;
ysr@777 871 int _global_pops;
ysr@777 872 int _global_max_size;
ysr@777 873
ysr@777 874 int _global_transfers_to;
ysr@777 875 int _global_transfers_from;
ysr@777 876
ysr@777 877 int _region_stack_pops;
ysr@777 878
ysr@777 879 int _regions_claimed;
ysr@777 880 int _objs_found_on_bitmap;
ysr@777 881
ysr@777 882 int _satb_buffers_processed;
ysr@777 883 #endif // _MARKING_STATS_
ysr@777 884
ysr@777 885 // it updates the local fields after this task has claimed
ysr@777 886 // a new region to scan
ysr@777 887 void setup_for_region(HeapRegion* hr);
ysr@777 888 // it brings up-to-date the limit of the region
ysr@777 889 void update_region_limit();
ysr@777 890 // it resets the local fields after a task has finished scanning a
ysr@777 891 // region
ysr@777 892 void giveup_current_region();
ysr@777 893
ysr@777 894 // called when either the words scanned or the refs visited limit
ysr@777 895 // has been reached
ysr@777 896 void reached_limit();
ysr@777 897 // recalculates the words scanned and refs visited limits
ysr@777 898 void recalculate_limits();
ysr@777 899 // decreases the words scanned and refs visited limits when we reach
ysr@777 900 // an expensive operation
ysr@777 901 void decrease_limits();
ysr@777 902 // it checks whether the words scanned or refs visited reached their
ysr@777 903 // respective limit and calls reached_limit() if they have
ysr@777 904 void check_limits() {
ysr@777 905 if (_words_scanned >= _words_scanned_limit ||
ysr@777 906 _refs_reached >= _refs_reached_limit)
ysr@777 907 reached_limit();
ysr@777 908 }
ysr@777 909 // this is supposed to be called regularly during a marking step as
ysr@777 910 // it checks a bunch of conditions that might cause the marking step
ysr@777 911 // to abort
ysr@777 912 void regular_clock_call();
ysr@777 913 bool concurrent() { return _concurrent; }
ysr@777 914
ysr@777 915 public:
ysr@777 916 // It resets the task; it should be called right at the beginning of
ysr@777 917 // a marking phase.
ysr@777 918 void reset(CMBitMap* _nextMarkBitMap);
ysr@777 919 // it clears all the fields that correspond to a claimed region.
ysr@777 920 void clear_region_fields();
ysr@777 921
ysr@777 922 void set_concurrent(bool concurrent) { _concurrent = concurrent; }
ysr@777 923
ysr@777 924 // The main method of this class which performs a marking step
ysr@777 925 // trying not to exceed the given duration. However, it might exit
ysr@777 926 // prematurely, according to some conditions (i.e. SATB buffers are
ysr@777 927 // available for processing).
ysr@777 928 void do_marking_step(double target_ms);
ysr@777 929
ysr@777 930 // These two calls start and stop the timer
ysr@777 931 void record_start_time() {
ysr@777 932 _elapsed_time_ms = os::elapsedTime() * 1000.0;
ysr@777 933 }
ysr@777 934 void record_end_time() {
ysr@777 935 _elapsed_time_ms = os::elapsedTime() * 1000.0 - _elapsed_time_ms;
ysr@777 936 }
ysr@777 937
ysr@777 938 // returns the task ID
ysr@777 939 int task_id() { return _task_id; }
ysr@777 940
ysr@777 941 // From TerminatorTerminator. It determines whether this task should
ysr@777 942 // exit the termination protocol after it's entered it.
ysr@777 943 virtual bool should_exit_termination();
ysr@777 944
ysr@777 945 HeapWord* finger() { return _finger; }
ysr@777 946
ysr@777 947 bool has_aborted() { return _has_aborted; }
ysr@777 948 void set_has_aborted() { _has_aborted = true; }
ysr@777 949 void clear_has_aborted() { _has_aborted = false; }
ysr@777 950 bool claimed() { return _claimed; }
ysr@777 951
ysr@777 952 void set_oop_closure(OopClosure* oop_closure) {
ysr@777 953 _oop_closure = oop_closure;
ysr@777 954 }
ysr@777 955
ysr@777 956 // It grays the object by marking it and, if necessary, pushing it
ysr@777 957 // on the local queue
ysr@777 958 void deal_with_reference(oop obj);
ysr@777 959
ysr@777 960 // It scans an object and visits its children.
ysr@777 961 void scan_object(oop obj) {
ysr@777 962 tmp_guarantee_CM( _nextMarkBitMap->isMarked((HeapWord*) obj),
ysr@777 963 "invariant" );
ysr@777 964
ysr@777 965 if (_cm->verbose_high())
ysr@777 966 gclog_or_tty->print_cr("[%d] we're scanning object "PTR_FORMAT,
ysr@777 967 _task_id, (void*) obj);
ysr@777 968
ysr@777 969 size_t obj_size = obj->size();
ysr@777 970 _words_scanned += obj_size;
ysr@777 971
ysr@777 972 obj->oop_iterate(_oop_closure);
ysr@777 973 statsOnly( ++_objs_scanned );
ysr@777 974 check_limits();
ysr@777 975 }
ysr@777 976
ysr@777 977 // It pushes an object on the local queue.
ysr@777 978 void push(oop obj);
ysr@777 979
ysr@777 980 // These two move entries to/from the global stack.
ysr@777 981 void move_entries_to_global_stack();
ysr@777 982 void get_entries_from_global_stack();
ysr@777 983
ysr@777 984 // It pops and scans objects from the local queue. If partially is
ysr@777 985 // true, then it stops when the queue size is of a given limit. If
ysr@777 986 // partially is false, then it stops when the queue is empty.
ysr@777 987 void drain_local_queue(bool partially);
ysr@777 988 // It moves entries from the global stack to the local queue and
ysr@777 989 // drains the local queue. If partially is true, then it stops when
ysr@777 990 // both the global stack and the local queue reach a given size. If
ysr@777 991 // partially if false, it tries to empty them totally.
ysr@777 992 void drain_global_stack(bool partially);
ysr@777 993 // It keeps picking SATB buffers and processing them until no SATB
ysr@777 994 // buffers are available.
ysr@777 995 void drain_satb_buffers();
ysr@777 996 // It keeps popping regions from the region stack and processing
ysr@777 997 // them until the region stack is empty.
ysr@777 998 void drain_region_stack(BitMapClosure* closure);
ysr@777 999
ysr@777 1000 // moves the local finger to a new location
ysr@777 1001 inline void move_finger_to(HeapWord* new_finger) {
ysr@777 1002 tmp_guarantee_CM( new_finger >= _finger && new_finger < _region_limit,
ysr@777 1003 "invariant" );
ysr@777 1004 _finger = new_finger;
ysr@777 1005 }
ysr@777 1006
ysr@777 1007 // moves the region finger to a new location
ysr@777 1008 inline void move_region_finger_to(HeapWord* new_finger) {
ysr@777 1009 tmp_guarantee_CM( new_finger < _cm->finger(), "invariant" );
ysr@777 1010 _region_finger = new_finger;
ysr@777 1011 }
ysr@777 1012
ysr@777 1013 CMTask(int task_num, ConcurrentMark *cm,
ysr@777 1014 CMTaskQueue* task_queue, CMTaskQueueSet* task_queues);
ysr@777 1015
ysr@777 1016 // it prints statistics associated with this task
ysr@777 1017 void print_stats();
ysr@777 1018
ysr@777 1019 #if _MARKING_STATS_
ysr@777 1020 void increase_objs_found_on_bitmap() { ++_objs_found_on_bitmap; }
ysr@777 1021 #endif // _MARKING_STATS_
ysr@777 1022 };

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