1 /*
2 * Copyright (c) 2001, 2010, Oracle and/or its affiliates. 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 #include "precompiled.hpp"
26 #include "gc_implementation/g1/concurrentG1Refine.hpp"
27 #include "gc_implementation/g1/g1BlockOffsetTable.inline.hpp"
28 #include "gc_implementation/g1/g1CollectedHeap.inline.hpp"
29 #include "gc_implementation/g1/heapRegionRemSet.hpp"
30 #include "gc_implementation/g1/heapRegionSeq.inline.hpp"
31 #include "memory/allocation.hpp"
32 #include "memory/space.inline.hpp"
33 #include "utilities/bitMap.inline.hpp"
34 #include "utilities/globalDefinitions.hpp"
35
36 #define HRRS_VERBOSE 0
37
38 #define PRT_COUNT_OCCUPIED 1
39
40 // OtherRegionsTable
41
42 class PerRegionTable: public CHeapObj {
43 friend class OtherRegionsTable;
44 friend class HeapRegionRemSetIterator;
45
46 HeapRegion* _hr;
47 BitMap _bm;
48 #if PRT_COUNT_OCCUPIED
49 jint _occupied;
50 #endif
51 PerRegionTable* _next_free;
52
53 PerRegionTable* next_free() { return _next_free; }
54 void set_next_free(PerRegionTable* prt) { _next_free = prt; }
55
56
57 static PerRegionTable* _free_list;
58
59 #ifdef _MSC_VER
60 // For some reason even though the classes are marked as friend they are unable
61 // to access CardsPerRegion when private/protected. Only the windows c++ compiler
62 // says this Sun CC and linux gcc don't have a problem with access when private
63
64 public:
65
66 #endif // _MSC_VER
67
68 protected:
69 // We need access in order to union things into the base table.
70 BitMap* bm() { return &_bm; }
71
72 #if PRT_COUNT_OCCUPIED
73 void recount_occupied() {
74 _occupied = (jint) bm()->count_one_bits();
75 }
76 #endif
77
78 PerRegionTable(HeapRegion* hr) :
79 _hr(hr),
80 #if PRT_COUNT_OCCUPIED
81 _occupied(0),
82 #endif
83 _bm(HeapRegion::CardsPerRegion, false /* in-resource-area */)
84 {}
85
86 static void free(PerRegionTable* prt) {
87 while (true) {
88 PerRegionTable* fl = _free_list;
89 prt->set_next_free(fl);
90 PerRegionTable* res =
91 (PerRegionTable*)
92 Atomic::cmpxchg_ptr(prt, &_free_list, fl);
93 if (res == fl) return;
94 }
95 ShouldNotReachHere();
96 }
97
98 static PerRegionTable* alloc(HeapRegion* hr) {
99 PerRegionTable* fl = _free_list;
100 while (fl != NULL) {
101 PerRegionTable* nxt = fl->next_free();
102 PerRegionTable* res =
103 (PerRegionTable*)
104 Atomic::cmpxchg_ptr(nxt, &_free_list, fl);
105 if (res == fl) {
106 fl->init(hr);
107 return fl;
108 } else {
109 fl = _free_list;
110 }
111 }
112 assert(fl == NULL, "Loop condition.");
113 return new PerRegionTable(hr);
114 }
115
116 void add_card_work(CardIdx_t from_card, bool par) {
117 if (!_bm.at(from_card)) {
118 if (par) {
119 if (_bm.par_at_put(from_card, 1)) {
120 #if PRT_COUNT_OCCUPIED
121 Atomic::inc(&_occupied);
122 #endif
123 }
124 } else {
125 _bm.at_put(from_card, 1);
126 #if PRT_COUNT_OCCUPIED
127 _occupied++;
128 #endif
129 }
130 }
131 }
132
133 void add_reference_work(OopOrNarrowOopStar from, bool par) {
134 // Must make this robust in case "from" is not in "_hr", because of
135 // concurrency.
136
137 #if HRRS_VERBOSE
138 gclog_or_tty->print_cr(" PRT::Add_reference_work(" PTR_FORMAT "->" PTR_FORMAT").",
139 from, *from);
140 #endif
141
142 HeapRegion* loc_hr = hr();
143 // If the test below fails, then this table was reused concurrently
144 // with this operation. This is OK, since the old table was coarsened,
145 // and adding a bit to the new table is never incorrect.
146 if (loc_hr->is_in_reserved(from)) {
147 size_t hw_offset = pointer_delta((HeapWord*)from, loc_hr->bottom());
148 CardIdx_t from_card = (CardIdx_t)
149 hw_offset >> (CardTableModRefBS::card_shift - LogHeapWordSize);
150
151 assert(0 <= from_card && from_card < HeapRegion::CardsPerRegion,
152 "Must be in range.");
153 add_card_work(from_card, par);
154 }
155 }
156
157 public:
158
159 HeapRegion* hr() const { return _hr; }
160
161 #if PRT_COUNT_OCCUPIED
162 jint occupied() const {
163 // Overkill, but if we ever need it...
164 // guarantee(_occupied == _bm.count_one_bits(), "Check");
165 return _occupied;
166 }
167 #else
168 jint occupied() const {
169 return _bm.count_one_bits();
170 }
171 #endif
172
173 void init(HeapRegion* hr) {
174 _hr = hr;
175 #if PRT_COUNT_OCCUPIED
176 _occupied = 0;
177 #endif
178 _bm.clear();
179 }
180
181 void add_reference(OopOrNarrowOopStar from) {
182 add_reference_work(from, /*parallel*/ true);
183 }
184
185 void seq_add_reference(OopOrNarrowOopStar from) {
186 add_reference_work(from, /*parallel*/ false);
187 }
188
189 void scrub(CardTableModRefBS* ctbs, BitMap* card_bm) {
190 HeapWord* hr_bot = hr()->bottom();
191 size_t hr_first_card_index = ctbs->index_for(hr_bot);
192 bm()->set_intersection_at_offset(*card_bm, hr_first_card_index);
193 #if PRT_COUNT_OCCUPIED
194 recount_occupied();
195 #endif
196 }
197
198 void add_card(CardIdx_t from_card_index) {
199 add_card_work(from_card_index, /*parallel*/ true);
200 }
201
202 void seq_add_card(CardIdx_t from_card_index) {
203 add_card_work(from_card_index, /*parallel*/ false);
204 }
205
206 // (Destructively) union the bitmap of the current table into the given
207 // bitmap (which is assumed to be of the same size.)
208 void union_bitmap_into(BitMap* bm) {
209 bm->set_union(_bm);
210 }
211
212 // Mem size in bytes.
213 size_t mem_size() const {
214 return sizeof(this) + _bm.size_in_words() * HeapWordSize;
215 }
216
217 static size_t fl_mem_size() {
218 PerRegionTable* cur = _free_list;
219 size_t res = 0;
220 while (cur != NULL) {
221 res += sizeof(PerRegionTable);
222 cur = cur->next_free();
223 }
224 return res;
225 }
226
227 // Requires "from" to be in "hr()".
228 bool contains_reference(OopOrNarrowOopStar from) const {
229 assert(hr()->is_in_reserved(from), "Precondition.");
230 size_t card_ind = pointer_delta(from, hr()->bottom(),
231 CardTableModRefBS::card_size);
232 return _bm.at(card_ind);
233 }
234 };
235
236 PerRegionTable* PerRegionTable::_free_list = NULL;
237
238
239 #define COUNT_PAR_EXPANDS 0
240
241 #if COUNT_PAR_EXPANDS
242 static jint n_par_expands = 0;
243 static jint n_par_contracts = 0;
244 static jint par_expand_list_len = 0;
245 static jint max_par_expand_list_len = 0;
246
247 static void print_par_expand() {
248 Atomic::inc(&n_par_expands);
249 Atomic::inc(&par_expand_list_len);
250 if (par_expand_list_len > max_par_expand_list_len) {
251 max_par_expand_list_len = par_expand_list_len;
252 }
253 if ((n_par_expands % 10) == 0) {
254 gclog_or_tty->print_cr("\n\n%d par expands: %d contracts, "
255 "len = %d, max_len = %d\n.",
256 n_par_expands, n_par_contracts, par_expand_list_len,
257 max_par_expand_list_len);
258 }
259 }
260 #endif
261
262 class PosParPRT: public PerRegionTable {
263 PerRegionTable** _par_tables;
264
265 enum SomePrivateConstants {
266 ReserveParTableExpansion = 1
267 };
268
269 void par_contract() {
270 assert(_par_tables != NULL, "Precondition.");
271 int n = HeapRegionRemSet::num_par_rem_sets()-1;
272 for (int i = 0; i < n; i++) {
273 _par_tables[i]->union_bitmap_into(bm());
274 PerRegionTable::free(_par_tables[i]);
275 _par_tables[i] = NULL;
276 }
277 #if PRT_COUNT_OCCUPIED
278 // We must recount the "occupied."
279 recount_occupied();
280 #endif
281 FREE_C_HEAP_ARRAY(PerRegionTable*, _par_tables);
282 _par_tables = NULL;
283 #if COUNT_PAR_EXPANDS
284 Atomic::inc(&n_par_contracts);
285 Atomic::dec(&par_expand_list_len);
286 #endif
287 }
288
289 static PerRegionTable** _par_table_fl;
290
291 PosParPRT* _next;
292
293 static PosParPRT* _free_list;
294
295 PerRegionTable** par_tables() const {
296 assert(uintptr_t(NULL) == 0, "Assumption.");
297 if (uintptr_t(_par_tables) <= ReserveParTableExpansion)
298 return NULL;
299 else
300 return _par_tables;
301 }
302
303 PosParPRT* _next_par_expanded;
304 PosParPRT* next_par_expanded() { return _next_par_expanded; }
305 void set_next_par_expanded(PosParPRT* ppprt) { _next_par_expanded = ppprt; }
306 static PosParPRT* _par_expanded_list;
307
308 public:
309
310 PosParPRT(HeapRegion* hr) : PerRegionTable(hr), _par_tables(NULL) {}
311
312 jint occupied() const {
313 jint res = PerRegionTable::occupied();
314 if (par_tables() != NULL) {
315 for (int i = 0; i < HeapRegionRemSet::num_par_rem_sets()-1; i++) {
316 res += par_tables()[i]->occupied();
317 }
318 }
319 return res;
320 }
321
322 void init(HeapRegion* hr) {
323 PerRegionTable::init(hr);
324 _next = NULL;
325 if (par_tables() != NULL) {
326 for (int i = 0; i < HeapRegionRemSet::num_par_rem_sets()-1; i++) {
327 par_tables()[i]->init(hr);
328 }
329 }
330 }
331
332 static void free(PosParPRT* prt) {
333 while (true) {
334 PosParPRT* fl = _free_list;
335 prt->set_next(fl);
336 PosParPRT* res =
337 (PosParPRT*)
338 Atomic::cmpxchg_ptr(prt, &_free_list, fl);
339 if (res == fl) return;
340 }
341 ShouldNotReachHere();
342 }
343
344 static PosParPRT* alloc(HeapRegion* hr) {
345 PosParPRT* fl = _free_list;
346 while (fl != NULL) {
347 PosParPRT* nxt = fl->next();
348 PosParPRT* res =
349 (PosParPRT*)
350 Atomic::cmpxchg_ptr(nxt, &_free_list, fl);
351 if (res == fl) {
352 fl->init(hr);
353 return fl;
354 } else {
355 fl = _free_list;
356 }
357 }
358 assert(fl == NULL, "Loop condition.");
359 return new PosParPRT(hr);
360 }
361
362 PosParPRT* next() const { return _next; }
363 void set_next(PosParPRT* nxt) { _next = nxt; }
364 PosParPRT** next_addr() { return &_next; }
365
366 bool should_expand(int tid) {
367 return par_tables() == NULL && tid > 0 && hr()->is_gc_alloc_region();
368 }
369
370 void par_expand() {
371 int n = HeapRegionRemSet::num_par_rem_sets()-1;
372 if (n <= 0) return;
373 if (_par_tables == NULL) {
374 PerRegionTable* res =
375 (PerRegionTable*)
376 Atomic::cmpxchg_ptr((PerRegionTable*)ReserveParTableExpansion,
377 &_par_tables, NULL);
378 if (res != NULL) return;
379 // Otherwise, we reserved the right to do the expansion.
380
381 PerRegionTable** ptables = NEW_C_HEAP_ARRAY(PerRegionTable*, n);
382 for (int i = 0; i < n; i++) {
383 PerRegionTable* ptable = PerRegionTable::alloc(hr());
384 ptables[i] = ptable;
385 }
386 // Here we do not need an atomic.
387 _par_tables = ptables;
388 #if COUNT_PAR_EXPANDS
389 print_par_expand();
390 #endif
391 // We must put this table on the expanded list.
392 PosParPRT* exp_head = _par_expanded_list;
393 while (true) {
394 set_next_par_expanded(exp_head);
395 PosParPRT* res =
396 (PosParPRT*)
397 Atomic::cmpxchg_ptr(this, &_par_expanded_list, exp_head);
398 if (res == exp_head) return;
399 // Otherwise.
400 exp_head = res;
401 }
402 ShouldNotReachHere();
403 }
404 }
405
406 void add_reference(OopOrNarrowOopStar from, int tid) {
407 // Expand if necessary.
408 PerRegionTable** pt = par_tables();
409 if (pt != NULL) {
410 // We always have to assume that mods to table 0 are in parallel,
411 // because of the claiming scheme in parallel expansion. A thread
412 // with tid != 0 that finds the table to be NULL, but doesn't succeed
413 // in claiming the right of expanding it, will end up in the else
414 // clause of the above if test. That thread could be delayed, and a
415 // thread 0 add reference could see the table expanded, and come
416 // here. Both threads would be adding in parallel. But we get to
417 // not use atomics for tids > 0.
418 if (tid == 0) {
419 PerRegionTable::add_reference(from);
420 } else {
421 pt[tid-1]->seq_add_reference(from);
422 }
423 } else {
424 // Not expanded -- add to the base table.
425 PerRegionTable::add_reference(from);
426 }
427 }
428
429 void scrub(CardTableModRefBS* ctbs, BitMap* card_bm) {
430 assert(_par_tables == NULL, "Precondition");
431 PerRegionTable::scrub(ctbs, card_bm);
432 }
433
434 size_t mem_size() const {
435 size_t res =
436 PerRegionTable::mem_size() + sizeof(this) - sizeof(PerRegionTable);
437 if (_par_tables != NULL) {
438 for (int i = 0; i < HeapRegionRemSet::num_par_rem_sets()-1; i++) {
439 res += _par_tables[i]->mem_size();
440 }
441 }
442 return res;
443 }
444
445 static size_t fl_mem_size() {
446 PosParPRT* cur = _free_list;
447 size_t res = 0;
448 while (cur != NULL) {
449 res += sizeof(PosParPRT);
450 cur = cur->next();
451 }
452 return res;
453 }
454
455 bool contains_reference(OopOrNarrowOopStar from) const {
456 if (PerRegionTable::contains_reference(from)) return true;
457 if (_par_tables != NULL) {
458 for (int i = 0; i < HeapRegionRemSet::num_par_rem_sets()-1; i++) {
459 if (_par_tables[i]->contains_reference(from)) return true;
460 }
461 }
462 return false;
463 }
464
465 static void par_contract_all();
466
467 };
468
469 void PosParPRT::par_contract_all() {
470 PosParPRT* hd = _par_expanded_list;
471 while (hd != NULL) {
472 PosParPRT* nxt = hd->next_par_expanded();
473 PosParPRT* res =
474 (PosParPRT*)
475 Atomic::cmpxchg_ptr(nxt, &_par_expanded_list, hd);
476 if (res == hd) {
477 // We claimed the right to contract this table.
478 hd->set_next_par_expanded(NULL);
479 hd->par_contract();
480 hd = _par_expanded_list;
481 } else {
482 hd = res;
483 }
484 }
485 }
486
487 PosParPRT* PosParPRT::_free_list = NULL;
488 PosParPRT* PosParPRT::_par_expanded_list = NULL;
489
490 jint OtherRegionsTable::_cache_probes = 0;
491 jint OtherRegionsTable::_cache_hits = 0;
492
493 size_t OtherRegionsTable::_max_fine_entries = 0;
494 size_t OtherRegionsTable::_mod_max_fine_entries_mask = 0;
495 #if SAMPLE_FOR_EVICTION
496 size_t OtherRegionsTable::_fine_eviction_stride = 0;
497 size_t OtherRegionsTable::_fine_eviction_sample_size = 0;
498 #endif
499
500 OtherRegionsTable::OtherRegionsTable(HeapRegion* hr) :
501 _g1h(G1CollectedHeap::heap()),
502 _m(Mutex::leaf, "An OtherRegionsTable lock", true),
503 _hr(hr),
504 _coarse_map(G1CollectedHeap::heap()->max_regions(),
505 false /* in-resource-area */),
506 _fine_grain_regions(NULL),
507 _n_fine_entries(0), _n_coarse_entries(0),
508 #if SAMPLE_FOR_EVICTION
509 _fine_eviction_start(0),
510 #endif
511 _sparse_table(hr)
512 {
513 typedef PosParPRT* PosParPRTPtr;
514 if (_max_fine_entries == 0) {
515 assert(_mod_max_fine_entries_mask == 0, "Both or none.");
516 size_t max_entries_log = (size_t)log2_long((jlong)G1RSetRegionEntries);
517 _max_fine_entries = (size_t)(1 << max_entries_log);
518 _mod_max_fine_entries_mask = _max_fine_entries - 1;
519 #if SAMPLE_FOR_EVICTION
520 assert(_fine_eviction_sample_size == 0
521 && _fine_eviction_stride == 0, "All init at same time.");
522 _fine_eviction_sample_size = MAX2((size_t)4, max_entries_log);
523 _fine_eviction_stride = _max_fine_entries / _fine_eviction_sample_size;
524 #endif
525 }
526 _fine_grain_regions = new PosParPRTPtr[_max_fine_entries];
527 if (_fine_grain_regions == NULL)
528 vm_exit_out_of_memory(sizeof(void*)*_max_fine_entries,
529 "Failed to allocate _fine_grain_entries.");
530 for (size_t i = 0; i < _max_fine_entries; i++) {
531 _fine_grain_regions[i] = NULL;
532 }
533 }
534
535 int** OtherRegionsTable::_from_card_cache = NULL;
536 size_t OtherRegionsTable::_from_card_cache_max_regions = 0;
537 size_t OtherRegionsTable::_from_card_cache_mem_size = 0;
538
539 void OtherRegionsTable::init_from_card_cache(size_t max_regions) {
540 _from_card_cache_max_regions = max_regions;
541
542 int n_par_rs = HeapRegionRemSet::num_par_rem_sets();
543 _from_card_cache = NEW_C_HEAP_ARRAY(int*, n_par_rs);
544 for (int i = 0; i < n_par_rs; i++) {
545 _from_card_cache[i] = NEW_C_HEAP_ARRAY(int, max_regions);
546 for (size_t j = 0; j < max_regions; j++) {
547 _from_card_cache[i][j] = -1; // An invalid value.
548 }
549 }
550 _from_card_cache_mem_size = n_par_rs * max_regions * sizeof(int);
551 }
552
553 void OtherRegionsTable::shrink_from_card_cache(size_t new_n_regs) {
554 for (int i = 0; i < HeapRegionRemSet::num_par_rem_sets(); i++) {
555 assert(new_n_regs <= _from_card_cache_max_regions, "Must be within max.");
556 for (size_t j = new_n_regs; j < _from_card_cache_max_regions; j++) {
557 _from_card_cache[i][j] = -1; // An invalid value.
558 }
559 }
560 }
561
562 #ifndef PRODUCT
563 void OtherRegionsTable::print_from_card_cache() {
564 for (int i = 0; i < HeapRegionRemSet::num_par_rem_sets(); i++) {
565 for (size_t j = 0; j < _from_card_cache_max_regions; j++) {
566 gclog_or_tty->print_cr("_from_card_cache[%d][%d] = %d.",
567 i, j, _from_card_cache[i][j]);
568 }
569 }
570 }
571 #endif
572
573 void OtherRegionsTable::add_reference(OopOrNarrowOopStar from, int tid) {
574 size_t cur_hrs_ind = hr()->hrs_index();
575
576 #if HRRS_VERBOSE
577 gclog_or_tty->print_cr("ORT::add_reference_work(" PTR_FORMAT "->" PTR_FORMAT ").",
578 from,
579 UseCompressedOops
580 ? oopDesc::load_decode_heap_oop((narrowOop*)from)
581 : oopDesc::load_decode_heap_oop((oop*)from));
582 #endif
583
584 int from_card = (int)(uintptr_t(from) >> CardTableModRefBS::card_shift);
585
586 #if HRRS_VERBOSE
587 gclog_or_tty->print_cr("Table for [" PTR_FORMAT "...): card %d (cache = %d)",
588 hr()->bottom(), from_card,
589 _from_card_cache[tid][cur_hrs_ind]);
590 #endif
591
592 #define COUNT_CACHE 0
593 #if COUNT_CACHE
594 jint p = Atomic::add(1, &_cache_probes);
595 if ((p % 10000) == 0) {
596 jint hits = _cache_hits;
597 gclog_or_tty->print_cr("%d/%d = %5.2f%% RS cache hits.",
598 _cache_hits, p, 100.0* (float)hits/(float)p);
599 }
600 #endif
601 if (from_card == _from_card_cache[tid][cur_hrs_ind]) {
602 #if HRRS_VERBOSE
603 gclog_or_tty->print_cr(" from-card cache hit.");
604 #endif
605 #if COUNT_CACHE
606 Atomic::inc(&_cache_hits);
607 #endif
608 assert(contains_reference(from), "We just added it!");
609 return;
610 } else {
611 _from_card_cache[tid][cur_hrs_ind] = from_card;
612 }
613
614 // Note that this may be a continued H region.
615 HeapRegion* from_hr = _g1h->heap_region_containing_raw(from);
616 RegionIdx_t from_hrs_ind = (RegionIdx_t) from_hr->hrs_index();
617
618 // If the region is already coarsened, return.
619 if (_coarse_map.at(from_hrs_ind)) {
620 #if HRRS_VERBOSE
621 gclog_or_tty->print_cr(" coarse map hit.");
622 #endif
623 assert(contains_reference(from), "We just added it!");
624 return;
625 }
626
627 // Otherwise find a per-region table to add it to.
628 size_t ind = from_hrs_ind & _mod_max_fine_entries_mask;
629 PosParPRT* prt = find_region_table(ind, from_hr);
630 if (prt == NULL) {
631 MutexLockerEx x(&_m, Mutex::_no_safepoint_check_flag);
632 // Confirm that it's really not there...
633 prt = find_region_table(ind, from_hr);
634 if (prt == NULL) {
635
636 uintptr_t from_hr_bot_card_index =
637 uintptr_t(from_hr->bottom())
638 >> CardTableModRefBS::card_shift;
639 CardIdx_t card_index = from_card - from_hr_bot_card_index;
640 assert(0 <= card_index && card_index < HeapRegion::CardsPerRegion,
641 "Must be in range.");
642 if (G1HRRSUseSparseTable &&
643 _sparse_table.add_card(from_hrs_ind, card_index)) {
644 if (G1RecordHRRSOops) {
645 HeapRegionRemSet::record(hr(), from);
646 #if HRRS_VERBOSE
647 gclog_or_tty->print(" Added card " PTR_FORMAT " to region "
648 "[" PTR_FORMAT "...) for ref " PTR_FORMAT ".\n",
649 align_size_down(uintptr_t(from),
650 CardTableModRefBS::card_size),
651 hr()->bottom(), from);
652 #endif
653 }
654 #if HRRS_VERBOSE
655 gclog_or_tty->print_cr(" added card to sparse table.");
656 #endif
657 assert(contains_reference_locked(from), "We just added it!");
658 return;
659 } else {
660 #if HRRS_VERBOSE
661 gclog_or_tty->print_cr(" [tid %d] sparse table entry "
662 "overflow(f: %d, t: %d)",
663 tid, from_hrs_ind, cur_hrs_ind);
664 #endif
665 }
666
667 if (_n_fine_entries == _max_fine_entries) {
668 prt = delete_region_table();
669 } else {
670 prt = PosParPRT::alloc(from_hr);
671 }
672 prt->init(from_hr);
673
674 PosParPRT* first_prt = _fine_grain_regions[ind];
675 prt->set_next(first_prt); // XXX Maybe move to init?
676 _fine_grain_regions[ind] = prt;
677 _n_fine_entries++;
678
679 if (G1HRRSUseSparseTable) {
680 // Transfer from sparse to fine-grain.
681 SparsePRTEntry *sprt_entry = _sparse_table.get_entry(from_hrs_ind);
682 assert(sprt_entry != NULL, "There should have been an entry");
683 for (int i = 0; i < SparsePRTEntry::cards_num(); i++) {
684 CardIdx_t c = sprt_entry->card(i);
685 if (c != SparsePRTEntry::NullEntry) {
686 prt->add_card(c);
687 }
688 }
689 // Now we can delete the sparse entry.
690 bool res = _sparse_table.delete_entry(from_hrs_ind);
691 assert(res, "It should have been there.");
692 }
693 }
694 assert(prt != NULL && prt->hr() == from_hr, "consequence");
695 }
696 // Note that we can't assert "prt->hr() == from_hr", because of the
697 // possibility of concurrent reuse. But see head comment of
698 // OtherRegionsTable for why this is OK.
699 assert(prt != NULL, "Inv");
700
701 if (prt->should_expand(tid)) {
702 MutexLockerEx x(&_m, Mutex::_no_safepoint_check_flag);
703 HeapRegion* prt_hr = prt->hr();
704 if (prt_hr == from_hr) {
705 // Make sure the table still corresponds to the same region
706 prt->par_expand();
707 prt->add_reference(from, tid);
708 }
709 // else: The table has been concurrently coarsened, evicted, and
710 // the table data structure re-used for another table. So, we
711 // don't need to add the reference any more given that the table
712 // has been coarsened and the whole region will be scanned anyway.
713 } else {
714 prt->add_reference(from, tid);
715 }
716 if (G1RecordHRRSOops) {
717 HeapRegionRemSet::record(hr(), from);
718 #if HRRS_VERBOSE
719 gclog_or_tty->print("Added card " PTR_FORMAT " to region "
720 "[" PTR_FORMAT "...) for ref " PTR_FORMAT ".\n",
721 align_size_down(uintptr_t(from),
722 CardTableModRefBS::card_size),
723 hr()->bottom(), from);
724 #endif
725 }
726 assert(contains_reference(from), "We just added it!");
727 }
728
729 PosParPRT*
730 OtherRegionsTable::find_region_table(size_t ind, HeapRegion* hr) const {
731 assert(0 <= ind && ind < _max_fine_entries, "Preconditions.");
732 PosParPRT* prt = _fine_grain_regions[ind];
733 while (prt != NULL && prt->hr() != hr) {
734 prt = prt->next();
735 }
736 // Loop postcondition is the method postcondition.
737 return prt;
738 }
739
740
741 #define DRT_CENSUS 0
742
743 #if DRT_CENSUS
744 static const int HistoSize = 6;
745 static int global_histo[HistoSize] = { 0, 0, 0, 0, 0, 0 };
746 static int coarsenings = 0;
747 static int occ_sum = 0;
748 #endif
749
750 jint OtherRegionsTable::_n_coarsenings = 0;
751
752 PosParPRT* OtherRegionsTable::delete_region_table() {
753 #if DRT_CENSUS
754 int histo[HistoSize] = { 0, 0, 0, 0, 0, 0 };
755 const int histo_limits[] = { 1, 4, 16, 64, 256, 2048 };
756 #endif
757
758 assert(_m.owned_by_self(), "Precondition");
759 assert(_n_fine_entries == _max_fine_entries, "Precondition");
760 PosParPRT* max = NULL;
761 jint max_occ = 0;
762 PosParPRT** max_prev;
763 size_t max_ind;
764
765 #if SAMPLE_FOR_EVICTION
766 size_t i = _fine_eviction_start;
767 for (size_t k = 0; k < _fine_eviction_sample_size; k++) {
768 size_t ii = i;
769 // Make sure we get a non-NULL sample.
770 while (_fine_grain_regions[ii] == NULL) {
771 ii++;
772 if (ii == _max_fine_entries) ii = 0;
773 guarantee(ii != i, "We must find one.");
774 }
775 PosParPRT** prev = &_fine_grain_regions[ii];
776 PosParPRT* cur = *prev;
777 while (cur != NULL) {
778 jint cur_occ = cur->occupied();
779 if (max == NULL || cur_occ > max_occ) {
780 max = cur;
781 max_prev = prev;
782 max_ind = i;
783 max_occ = cur_occ;
784 }
785 prev = cur->next_addr();
786 cur = cur->next();
787 }
788 i = i + _fine_eviction_stride;
789 if (i >= _n_fine_entries) i = i - _n_fine_entries;
790 }
791 _fine_eviction_start++;
792 if (_fine_eviction_start >= _n_fine_entries)
793 _fine_eviction_start -= _n_fine_entries;
794 #else
795 for (int i = 0; i < _max_fine_entries; i++) {
796 PosParPRT** prev = &_fine_grain_regions[i];
797 PosParPRT* cur = *prev;
798 while (cur != NULL) {
799 jint cur_occ = cur->occupied();
800 #if DRT_CENSUS
801 for (int k = 0; k < HistoSize; k++) {
802 if (cur_occ <= histo_limits[k]) {
803 histo[k]++; global_histo[k]++; break;
804 }
805 }
806 #endif
807 if (max == NULL || cur_occ > max_occ) {
808 max = cur;
809 max_prev = prev;
810 max_ind = i;
811 max_occ = cur_occ;
812 }
813 prev = cur->next_addr();
814 cur = cur->next();
815 }
816 }
817 #endif
818 // XXX
819 guarantee(max != NULL, "Since _n_fine_entries > 0");
820 #if DRT_CENSUS
821 gclog_or_tty->print_cr("In a coarsening: histo of occs:");
822 for (int k = 0; k < HistoSize; k++) {
823 gclog_or_tty->print_cr(" <= %4d: %5d.", histo_limits[k], histo[k]);
824 }
825 coarsenings++;
826 occ_sum += max_occ;
827 if ((coarsenings % 100) == 0) {
828 gclog_or_tty->print_cr("\ncoarsenings = %d; global summary:", coarsenings);
829 for (int k = 0; k < HistoSize; k++) {
830 gclog_or_tty->print_cr(" <= %4d: %5d.", histo_limits[k], global_histo[k]);
831 }
832 gclog_or_tty->print_cr("Avg occ of deleted region = %6.2f.",
833 (float)occ_sum/(float)coarsenings);
834 }
835 #endif
836
837 // Set the corresponding coarse bit.
838 int max_hrs_index = max->hr()->hrs_index();
839 if (!_coarse_map.at(max_hrs_index)) {
840 _coarse_map.at_put(max_hrs_index, true);
841 _n_coarse_entries++;
842 #if 0
843 gclog_or_tty->print("Coarsened entry in region [" PTR_FORMAT "...] "
844 "for region [" PTR_FORMAT "...] (%d coarse entries).\n",
845 hr()->bottom(),
846 max->hr()->bottom(),
847 _n_coarse_entries);
848 #endif
849 }
850
851 // Unsplice.
852 *max_prev = max->next();
853 Atomic::inc(&_n_coarsenings);
854 _n_fine_entries--;
855 return max;
856 }
857
858
859 // At present, this must be called stop-world single-threaded.
860 void OtherRegionsTable::scrub(CardTableModRefBS* ctbs,
861 BitMap* region_bm, BitMap* card_bm) {
862 // First eliminated garbage regions from the coarse map.
863 if (G1RSScrubVerbose)
864 gclog_or_tty->print_cr("Scrubbing region %d:", hr()->hrs_index());
865
866 assert(_coarse_map.size() == region_bm->size(), "Precondition");
867 if (G1RSScrubVerbose)
868 gclog_or_tty->print(" Coarse map: before = %d...", _n_coarse_entries);
869 _coarse_map.set_intersection(*region_bm);
870 _n_coarse_entries = _coarse_map.count_one_bits();
871 if (G1RSScrubVerbose)
872 gclog_or_tty->print_cr(" after = %d.", _n_coarse_entries);
873
874 // Now do the fine-grained maps.
875 for (size_t i = 0; i < _max_fine_entries; i++) {
876 PosParPRT* cur = _fine_grain_regions[i];
877 PosParPRT** prev = &_fine_grain_regions[i];
878 while (cur != NULL) {
879 PosParPRT* nxt = cur->next();
880 // If the entire region is dead, eliminate.
881 if (G1RSScrubVerbose)
882 gclog_or_tty->print_cr(" For other region %d:", cur->hr()->hrs_index());
883 if (!region_bm->at(cur->hr()->hrs_index())) {
884 *prev = nxt;
885 cur->set_next(NULL);
886 _n_fine_entries--;
887 if (G1RSScrubVerbose)
888 gclog_or_tty->print_cr(" deleted via region map.");
889 PosParPRT::free(cur);
890 } else {
891 // Do fine-grain elimination.
892 if (G1RSScrubVerbose)
893 gclog_or_tty->print(" occ: before = %4d.", cur->occupied());
894 cur->scrub(ctbs, card_bm);
895 if (G1RSScrubVerbose)
896 gclog_or_tty->print_cr(" after = %4d.", cur->occupied());
897 // Did that empty the table completely?
898 if (cur->occupied() == 0) {
899 *prev = nxt;
900 cur->set_next(NULL);
901 _n_fine_entries--;
902 PosParPRT::free(cur);
903 } else {
904 prev = cur->next_addr();
905 }
906 }
907 cur = nxt;
908 }
909 }
910 // Since we may have deleted a from_card_cache entry from the RS, clear
911 // the FCC.
912 clear_fcc();
913 }
914
915
916 size_t OtherRegionsTable::occupied() const {
917 // Cast away const in this case.
918 MutexLockerEx x((Mutex*)&_m, Mutex::_no_safepoint_check_flag);
919 size_t sum = occ_fine();
920 sum += occ_sparse();
921 sum += occ_coarse();
922 return sum;
923 }
924
925 size_t OtherRegionsTable::occ_fine() const {
926 size_t sum = 0;
927 for (size_t i = 0; i < _max_fine_entries; i++) {
928 PosParPRT* cur = _fine_grain_regions[i];
929 while (cur != NULL) {
930 sum += cur->occupied();
931 cur = cur->next();
932 }
933 }
934 return sum;
935 }
936
937 size_t OtherRegionsTable::occ_coarse() const {
938 return (_n_coarse_entries * HeapRegion::CardsPerRegion);
939 }
940
941 size_t OtherRegionsTable::occ_sparse() const {
942 return _sparse_table.occupied();
943 }
944
945 size_t OtherRegionsTable::mem_size() const {
946 // Cast away const in this case.
947 MutexLockerEx x((Mutex*)&_m, Mutex::_no_safepoint_check_flag);
948 size_t sum = 0;
949 for (size_t i = 0; i < _max_fine_entries; i++) {
950 PosParPRT* cur = _fine_grain_regions[i];
951 while (cur != NULL) {
952 sum += cur->mem_size();
953 cur = cur->next();
954 }
955 }
956 sum += (sizeof(PosParPRT*) * _max_fine_entries);
957 sum += (_coarse_map.size_in_words() * HeapWordSize);
958 sum += (_sparse_table.mem_size());
959 sum += sizeof(*this) - sizeof(_sparse_table); // Avoid double counting above.
960 return sum;
961 }
962
963 size_t OtherRegionsTable::static_mem_size() {
964 return _from_card_cache_mem_size;
965 }
966
967 size_t OtherRegionsTable::fl_mem_size() {
968 return PerRegionTable::fl_mem_size() + PosParPRT::fl_mem_size();
969 }
970
971 void OtherRegionsTable::clear_fcc() {
972 for (int i = 0; i < HeapRegionRemSet::num_par_rem_sets(); i++) {
973 _from_card_cache[i][hr()->hrs_index()] = -1;
974 }
975 }
976
977 void OtherRegionsTable::clear() {
978 MutexLockerEx x(&_m, Mutex::_no_safepoint_check_flag);
979 for (size_t i = 0; i < _max_fine_entries; i++) {
980 PosParPRT* cur = _fine_grain_regions[i];
981 while (cur != NULL) {
982 PosParPRT* nxt = cur->next();
983 PosParPRT::free(cur);
984 cur = nxt;
985 }
986 _fine_grain_regions[i] = NULL;
987 }
988 _sparse_table.clear();
989 _coarse_map.clear();
990 _n_fine_entries = 0;
991 _n_coarse_entries = 0;
992
993 clear_fcc();
994 }
995
996 void OtherRegionsTable::clear_incoming_entry(HeapRegion* from_hr) {
997 MutexLockerEx x(&_m, Mutex::_no_safepoint_check_flag);
998 size_t hrs_ind = (size_t)from_hr->hrs_index();
999 size_t ind = hrs_ind & _mod_max_fine_entries_mask;
1000 if (del_single_region_table(ind, from_hr)) {
1001 assert(!_coarse_map.at(hrs_ind), "Inv");
1002 } else {
1003 _coarse_map.par_at_put(hrs_ind, 0);
1004 }
1005 // Check to see if any of the fcc entries come from here.
1006 int hr_ind = hr()->hrs_index();
1007 for (int tid = 0; tid < HeapRegionRemSet::num_par_rem_sets(); tid++) {
1008 int fcc_ent = _from_card_cache[tid][hr_ind];
1009 if (fcc_ent != -1) {
1010 HeapWord* card_addr = (HeapWord*)
1011 (uintptr_t(fcc_ent) << CardTableModRefBS::card_shift);
1012 if (hr()->is_in_reserved(card_addr)) {
1013 // Clear the from card cache.
1014 _from_card_cache[tid][hr_ind] = -1;
1015 }
1016 }
1017 }
1018 }
1019
1020 bool OtherRegionsTable::del_single_region_table(size_t ind,
1021 HeapRegion* hr) {
1022 assert(0 <= ind && ind < _max_fine_entries, "Preconditions.");
1023 PosParPRT** prev_addr = &_fine_grain_regions[ind];
1024 PosParPRT* prt = *prev_addr;
1025 while (prt != NULL && prt->hr() != hr) {
1026 prev_addr = prt->next_addr();
1027 prt = prt->next();
1028 }
1029 if (prt != NULL) {
1030 assert(prt->hr() == hr, "Loop postcondition.");
1031 *prev_addr = prt->next();
1032 PosParPRT::free(prt);
1033 _n_fine_entries--;
1034 return true;
1035 } else {
1036 return false;
1037 }
1038 }
1039
1040 bool OtherRegionsTable::contains_reference(OopOrNarrowOopStar from) const {
1041 // Cast away const in this case.
1042 MutexLockerEx x((Mutex*)&_m, Mutex::_no_safepoint_check_flag);
1043 return contains_reference_locked(from);
1044 }
1045
1046 bool OtherRegionsTable::contains_reference_locked(OopOrNarrowOopStar from) const {
1047 HeapRegion* hr = _g1h->heap_region_containing_raw(from);
1048 if (hr == NULL) return false;
1049 RegionIdx_t hr_ind = (RegionIdx_t) hr->hrs_index();
1050 // Is this region in the coarse map?
1051 if (_coarse_map.at(hr_ind)) return true;
1052
1053 PosParPRT* prt = find_region_table(hr_ind & _mod_max_fine_entries_mask,
1054 hr);
1055 if (prt != NULL) {
1056 return prt->contains_reference(from);
1057
1058 } else {
1059 uintptr_t from_card =
1060 (uintptr_t(from) >> CardTableModRefBS::card_shift);
1061 uintptr_t hr_bot_card_index =
1062 uintptr_t(hr->bottom()) >> CardTableModRefBS::card_shift;
1063 assert(from_card >= hr_bot_card_index, "Inv");
1064 CardIdx_t card_index = from_card - hr_bot_card_index;
1065 assert(0 <= card_index && card_index < HeapRegion::CardsPerRegion,
1066 "Must be in range.");
1067 return _sparse_table.contains_card(hr_ind, card_index);
1068 }
1069
1070
1071 }
1072
1073 // Determines how many threads can add records to an rset in parallel.
1074 // This can be done by either mutator threads together with the
1075 // concurrent refinement threads or GC threads.
1076 int HeapRegionRemSet::num_par_rem_sets() {
1077 return (int)MAX2(DirtyCardQueueSet::num_par_ids() + ConcurrentG1Refine::thread_num(), ParallelGCThreads);
1078 }
1079
1080 HeapRegionRemSet::HeapRegionRemSet(G1BlockOffsetSharedArray* bosa,
1081 HeapRegion* hr)
1082 : _bosa(bosa), _other_regions(hr), _iter_state(Unclaimed) { }
1083
1084
1085 void HeapRegionRemSet::setup_remset_size() {
1086 // Setup sparse and fine-grain tables sizes.
1087 // table_size = base * (log(region_size / 1M) + 1)
1088 int region_size_log_mb = MAX2((int)HeapRegion::LogOfHRGrainBytes - (int)LOG_M, 0);
1089 if (FLAG_IS_DEFAULT(G1RSetSparseRegionEntries)) {
1090 G1RSetSparseRegionEntries = G1RSetSparseRegionEntriesBase * (region_size_log_mb + 1);
1091 }
1092 if (FLAG_IS_DEFAULT(G1RSetRegionEntries)) {
1093 G1RSetRegionEntries = G1RSetRegionEntriesBase * (region_size_log_mb + 1);
1094 }
1095 guarantee(G1RSetSparseRegionEntries > 0 && G1RSetRegionEntries > 0 , "Sanity");
1096 }
1097
1098 void HeapRegionRemSet::init_for_par_iteration() {
1099 _iter_state = Unclaimed;
1100 }
1101
1102 bool HeapRegionRemSet::claim_iter() {
1103 if (_iter_state != Unclaimed) return false;
1104 jint res = Atomic::cmpxchg(Claimed, (jint*)(&_iter_state), Unclaimed);
1105 return (res == Unclaimed);
1106 }
1107
1108 void HeapRegionRemSet::set_iter_complete() {
1109 _iter_state = Complete;
1110 }
1111
1112 bool HeapRegionRemSet::iter_is_complete() {
1113 return _iter_state == Complete;
1114 }
1115
1116
1117 void HeapRegionRemSet::init_iterator(HeapRegionRemSetIterator* iter) const {
1118 iter->initialize(this);
1119 }
1120
1121 #ifndef PRODUCT
1122 void HeapRegionRemSet::print() const {
1123 HeapRegionRemSetIterator iter;
1124 init_iterator(&iter);
1125 size_t card_index;
1126 while (iter.has_next(card_index)) {
1127 HeapWord* card_start =
1128 G1CollectedHeap::heap()->bot_shared()->address_for_index(card_index);
1129 gclog_or_tty->print_cr(" Card " PTR_FORMAT ".", card_start);
1130 }
1131 // XXX
1132 if (iter.n_yielded() != occupied()) {
1133 gclog_or_tty->print_cr("Yielded disagrees with occupied:");
1134 gclog_or_tty->print_cr(" %6d yielded (%6d coarse, %6d fine).",
1135 iter.n_yielded(),
1136 iter.n_yielded_coarse(), iter.n_yielded_fine());
1137 gclog_or_tty->print_cr(" %6d occ (%6d coarse, %6d fine).",
1138 occupied(), occ_coarse(), occ_fine());
1139 }
1140 guarantee(iter.n_yielded() == occupied(),
1141 "We should have yielded all the represented cards.");
1142 }
1143 #endif
1144
1145 void HeapRegionRemSet::cleanup() {
1146 SparsePRT::cleanup_all();
1147 }
1148
1149 void HeapRegionRemSet::par_cleanup() {
1150 PosParPRT::par_contract_all();
1151 }
1152
1153 void HeapRegionRemSet::clear() {
1154 _other_regions.clear();
1155 assert(occupied() == 0, "Should be clear.");
1156 }
1157
1158 void HeapRegionRemSet::scrub(CardTableModRefBS* ctbs,
1159 BitMap* region_bm, BitMap* card_bm) {
1160 _other_regions.scrub(ctbs, region_bm, card_bm);
1161 }
1162
1163 //-------------------- Iteration --------------------
1164
1165 HeapRegionRemSetIterator::
1166 HeapRegionRemSetIterator() :
1167 _hrrs(NULL),
1168 _g1h(G1CollectedHeap::heap()),
1169 _bosa(NULL),
1170 _sparse_iter(size_t(G1CollectedHeap::heap()->reserved_region().start())
1171 >> CardTableModRefBS::card_shift)
1172 {}
1173
1174 void HeapRegionRemSetIterator::initialize(const HeapRegionRemSet* hrrs) {
1175 _hrrs = hrrs;
1176 _coarse_map = &_hrrs->_other_regions._coarse_map;
1177 _fine_grain_regions = _hrrs->_other_regions._fine_grain_regions;
1178 _bosa = _hrrs->bosa();
1179
1180 _is = Sparse;
1181 // Set these values so that we increment to the first region.
1182 _coarse_cur_region_index = -1;
1183 _coarse_cur_region_cur_card = (HeapRegion::CardsPerRegion-1);;
1184
1185 _cur_region_cur_card = 0;
1186
1187 _fine_array_index = -1;
1188 _fine_cur_prt = NULL;
1189
1190 _n_yielded_coarse = 0;
1191 _n_yielded_fine = 0;
1192 _n_yielded_sparse = 0;
1193
1194 _sparse_iter.init(&hrrs->_other_regions._sparse_table);
1195 }
1196
1197 bool HeapRegionRemSetIterator::coarse_has_next(size_t& card_index) {
1198 if (_hrrs->_other_regions._n_coarse_entries == 0) return false;
1199 // Go to the next card.
1200 _coarse_cur_region_cur_card++;
1201 // Was the last the last card in the current region?
1202 if (_coarse_cur_region_cur_card == HeapRegion::CardsPerRegion) {
1203 // Yes: find the next region. This may leave _coarse_cur_region_index
1204 // Set to the last index, in which case there are no more coarse
1205 // regions.
1206 _coarse_cur_region_index =
1207 (int) _coarse_map->get_next_one_offset(_coarse_cur_region_index + 1);
1208 if ((size_t)_coarse_cur_region_index < _coarse_map->size()) {
1209 _coarse_cur_region_cur_card = 0;
1210 HeapWord* r_bot =
1211 _g1h->region_at(_coarse_cur_region_index)->bottom();
1212 _cur_region_card_offset = _bosa->index_for(r_bot);
1213 } else {
1214 return false;
1215 }
1216 }
1217 // If we didn't return false above, then we can yield a card.
1218 card_index = _cur_region_card_offset + _coarse_cur_region_cur_card;
1219 return true;
1220 }
1221
1222 void HeapRegionRemSetIterator::fine_find_next_non_null_prt() {
1223 // Otherwise, find the next bucket list in the array.
1224 _fine_array_index++;
1225 while (_fine_array_index < (int) OtherRegionsTable::_max_fine_entries) {
1226 _fine_cur_prt = _fine_grain_regions[_fine_array_index];
1227 if (_fine_cur_prt != NULL) return;
1228 else _fine_array_index++;
1229 }
1230 assert(_fine_cur_prt == NULL, "Loop post");
1231 }
1232
1233 bool HeapRegionRemSetIterator::fine_has_next(size_t& card_index) {
1234 if (fine_has_next()) {
1235 _cur_region_cur_card =
1236 _fine_cur_prt->_bm.get_next_one_offset(_cur_region_cur_card + 1);
1237 }
1238 while (!fine_has_next()) {
1239 if (_cur_region_cur_card == (size_t) HeapRegion::CardsPerRegion) {
1240 _cur_region_cur_card = 0;
1241 _fine_cur_prt = _fine_cur_prt->next();
1242 }
1243 if (_fine_cur_prt == NULL) {
1244 fine_find_next_non_null_prt();
1245 if (_fine_cur_prt == NULL) return false;
1246 }
1247 assert(_fine_cur_prt != NULL && _cur_region_cur_card == 0,
1248 "inv.");
1249 HeapWord* r_bot =
1250 _fine_cur_prt->hr()->bottom();
1251 _cur_region_card_offset = _bosa->index_for(r_bot);
1252 _cur_region_cur_card = _fine_cur_prt->_bm.get_next_one_offset(0);
1253 }
1254 assert(fine_has_next(), "Or else we exited the loop via the return.");
1255 card_index = _cur_region_card_offset + _cur_region_cur_card;
1256 return true;
1257 }
1258
1259 bool HeapRegionRemSetIterator::fine_has_next() {
1260 return
1261 _fine_cur_prt != NULL &&
1262 _cur_region_cur_card < (size_t) HeapRegion::CardsPerRegion;
1263 }
1264
1265 bool HeapRegionRemSetIterator::has_next(size_t& card_index) {
1266 switch (_is) {
1267 case Sparse:
1268 if (_sparse_iter.has_next(card_index)) {
1269 _n_yielded_sparse++;
1270 return true;
1271 }
1272 // Otherwise, deliberate fall-through
1273 _is = Fine;
1274 case Fine:
1275 if (fine_has_next(card_index)) {
1276 _n_yielded_fine++;
1277 return true;
1278 }
1279 // Otherwise, deliberate fall-through
1280 _is = Coarse;
1281 case Coarse:
1282 if (coarse_has_next(card_index)) {
1283 _n_yielded_coarse++;
1284 return true;
1285 }
1286 // Otherwise...
1287 break;
1288 }
1289 assert(ParallelGCThreads > 1 ||
1290 n_yielded() == _hrrs->occupied(),
1291 "Should have yielded all the cards in the rem set "
1292 "(in the non-par case).");
1293 return false;
1294 }
1295
1296
1297
1298 OopOrNarrowOopStar* HeapRegionRemSet::_recorded_oops = NULL;
1299 HeapWord** HeapRegionRemSet::_recorded_cards = NULL;
1300 HeapRegion** HeapRegionRemSet::_recorded_regions = NULL;
1301 int HeapRegionRemSet::_n_recorded = 0;
1302
1303 HeapRegionRemSet::Event* HeapRegionRemSet::_recorded_events = NULL;
1304 int* HeapRegionRemSet::_recorded_event_index = NULL;
1305 int HeapRegionRemSet::_n_recorded_events = 0;
1306
1307 void HeapRegionRemSet::record(HeapRegion* hr, OopOrNarrowOopStar f) {
1308 if (_recorded_oops == NULL) {
1309 assert(_n_recorded == 0
1310 && _recorded_cards == NULL
1311 && _recorded_regions == NULL,
1312 "Inv");
1313 _recorded_oops = NEW_C_HEAP_ARRAY(OopOrNarrowOopStar, MaxRecorded);
1314 _recorded_cards = NEW_C_HEAP_ARRAY(HeapWord*, MaxRecorded);
1315 _recorded_regions = NEW_C_HEAP_ARRAY(HeapRegion*, MaxRecorded);
1316 }
1317 if (_n_recorded == MaxRecorded) {
1318 gclog_or_tty->print_cr("Filled up 'recorded' (%d).", MaxRecorded);
1319 } else {
1320 _recorded_cards[_n_recorded] =
1321 (HeapWord*)align_size_down(uintptr_t(f),
1322 CardTableModRefBS::card_size);
1323 _recorded_oops[_n_recorded] = f;
1324 _recorded_regions[_n_recorded] = hr;
1325 _n_recorded++;
1326 }
1327 }
1328
1329 void HeapRegionRemSet::record_event(Event evnt) {
1330 if (!G1RecordHRRSEvents) return;
1331
1332 if (_recorded_events == NULL) {
1333 assert(_n_recorded_events == 0
1334 && _recorded_event_index == NULL,
1335 "Inv");
1336 _recorded_events = NEW_C_HEAP_ARRAY(Event, MaxRecordedEvents);
1337 _recorded_event_index = NEW_C_HEAP_ARRAY(int, MaxRecordedEvents);
1338 }
1339 if (_n_recorded_events == MaxRecordedEvents) {
1340 gclog_or_tty->print_cr("Filled up 'recorded_events' (%d).", MaxRecordedEvents);
1341 } else {
1342 _recorded_events[_n_recorded_events] = evnt;
1343 _recorded_event_index[_n_recorded_events] = _n_recorded;
1344 _n_recorded_events++;
1345 }
1346 }
1347
1348 void HeapRegionRemSet::print_event(outputStream* str, Event evnt) {
1349 switch (evnt) {
1350 case Event_EvacStart:
1351 str->print("Evac Start");
1352 break;
1353 case Event_EvacEnd:
1354 str->print("Evac End");
1355 break;
1356 case Event_RSUpdateEnd:
1357 str->print("RS Update End");
1358 break;
1359 }
1360 }
1361
1362 void HeapRegionRemSet::print_recorded() {
1363 int cur_evnt = 0;
1364 Event cur_evnt_kind;
1365 int cur_evnt_ind = 0;
1366 if (_n_recorded_events > 0) {
1367 cur_evnt_kind = _recorded_events[cur_evnt];
1368 cur_evnt_ind = _recorded_event_index[cur_evnt];
1369 }
1370
1371 for (int i = 0; i < _n_recorded; i++) {
1372 while (cur_evnt < _n_recorded_events && i == cur_evnt_ind) {
1373 gclog_or_tty->print("Event: ");
1374 print_event(gclog_or_tty, cur_evnt_kind);
1375 gclog_or_tty->print_cr("");
1376 cur_evnt++;
1377 if (cur_evnt < MaxRecordedEvents) {
1378 cur_evnt_kind = _recorded_events[cur_evnt];
1379 cur_evnt_ind = _recorded_event_index[cur_evnt];
1380 }
1381 }
1382 gclog_or_tty->print("Added card " PTR_FORMAT " to region [" PTR_FORMAT "...]"
1383 " for ref " PTR_FORMAT ".\n",
1384 _recorded_cards[i], _recorded_regions[i]->bottom(),
1385 _recorded_oops[i]);
1386 }
1387 }
1388
1389 #ifndef PRODUCT
1390 void HeapRegionRemSet::test() {
1391 os::sleep(Thread::current(), (jlong)5000, false);
1392 G1CollectedHeap* g1h = G1CollectedHeap::heap();
1393
1394 // Run with "-XX:G1LogRSetRegionEntries=2", so that 1 and 5 end up in same
1395 // hash bucket.
1396 HeapRegion* hr0 = g1h->region_at(0);
1397 HeapRegion* hr1 = g1h->region_at(1);
1398 HeapRegion* hr2 = g1h->region_at(5);
1399 HeapRegion* hr3 = g1h->region_at(6);
1400 HeapRegion* hr4 = g1h->region_at(7);
1401 HeapRegion* hr5 = g1h->region_at(8);
1402
1403 HeapWord* hr1_start = hr1->bottom();
1404 HeapWord* hr1_mid = hr1_start + HeapRegion::GrainWords/2;
1405 HeapWord* hr1_last = hr1->end() - 1;
1406
1407 HeapWord* hr2_start = hr2->bottom();
1408 HeapWord* hr2_mid = hr2_start + HeapRegion::GrainWords/2;
1409 HeapWord* hr2_last = hr2->end() - 1;
1410
1411 HeapWord* hr3_start = hr3->bottom();
1412 HeapWord* hr3_mid = hr3_start + HeapRegion::GrainWords/2;
1413 HeapWord* hr3_last = hr3->end() - 1;
1414
1415 HeapRegionRemSet* hrrs = hr0->rem_set();
1416
1417 // Make three references from region 0x101...
1418 hrrs->add_reference((OopOrNarrowOopStar)hr1_start);
1419 hrrs->add_reference((OopOrNarrowOopStar)hr1_mid);
1420 hrrs->add_reference((OopOrNarrowOopStar)hr1_last);
1421
1422 hrrs->add_reference((OopOrNarrowOopStar)hr2_start);
1423 hrrs->add_reference((OopOrNarrowOopStar)hr2_mid);
1424 hrrs->add_reference((OopOrNarrowOopStar)hr2_last);
1425
1426 hrrs->add_reference((OopOrNarrowOopStar)hr3_start);
1427 hrrs->add_reference((OopOrNarrowOopStar)hr3_mid);
1428 hrrs->add_reference((OopOrNarrowOopStar)hr3_last);
1429
1430 // Now cause a coarsening.
1431 hrrs->add_reference((OopOrNarrowOopStar)hr4->bottom());
1432 hrrs->add_reference((OopOrNarrowOopStar)hr5->bottom());
1433
1434 // Now, does iteration yield these three?
1435 HeapRegionRemSetIterator iter;
1436 hrrs->init_iterator(&iter);
1437 size_t sum = 0;
1438 size_t card_index;
1439 while (iter.has_next(card_index)) {
1440 HeapWord* card_start =
1441 G1CollectedHeap::heap()->bot_shared()->address_for_index(card_index);
1442 gclog_or_tty->print_cr(" Card " PTR_FORMAT ".", card_start);
1443 sum++;
1444 }
1445 guarantee(sum == 11 - 3 + 2048, "Failure");
1446 guarantee(sum == hrrs->occupied(), "Failure");
1447 }
1448 #endif