1 /*
2 * Copyright (c) 2001, 2011, 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 && (size_t)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 // Given that we now defer RSet updates for after a GC we don't
368 // really need to expand the tables any more. This code should be
369 // cleaned up in the future (see CR 6921087).
370 return false;
371 }
372
373 void par_expand() {
374 int n = HeapRegionRemSet::num_par_rem_sets()-1;
375 if (n <= 0) return;
376 if (_par_tables == NULL) {
377 PerRegionTable* res =
378 (PerRegionTable*)
379 Atomic::cmpxchg_ptr((PerRegionTable*)ReserveParTableExpansion,
380 &_par_tables, NULL);
381 if (res != NULL) return;
382 // Otherwise, we reserved the right to do the expansion.
383
384 PerRegionTable** ptables = NEW_C_HEAP_ARRAY(PerRegionTable*, n);
385 for (int i = 0; i < n; i++) {
386 PerRegionTable* ptable = PerRegionTable::alloc(hr());
387 ptables[i] = ptable;
388 }
389 // Here we do not need an atomic.
390 _par_tables = ptables;
391 #if COUNT_PAR_EXPANDS
392 print_par_expand();
393 #endif
394 // We must put this table on the expanded list.
395 PosParPRT* exp_head = _par_expanded_list;
396 while (true) {
397 set_next_par_expanded(exp_head);
398 PosParPRT* res =
399 (PosParPRT*)
400 Atomic::cmpxchg_ptr(this, &_par_expanded_list, exp_head);
401 if (res == exp_head) return;
402 // Otherwise.
403 exp_head = res;
404 }
405 ShouldNotReachHere();
406 }
407 }
408
409 void add_reference(OopOrNarrowOopStar from, int tid) {
410 // Expand if necessary.
411 PerRegionTable** pt = par_tables();
412 if (pt != NULL) {
413 // We always have to assume that mods to table 0 are in parallel,
414 // because of the claiming scheme in parallel expansion. A thread
415 // with tid != 0 that finds the table to be NULL, but doesn't succeed
416 // in claiming the right of expanding it, will end up in the else
417 // clause of the above if test. That thread could be delayed, and a
418 // thread 0 add reference could see the table expanded, and come
419 // here. Both threads would be adding in parallel. But we get to
420 // not use atomics for tids > 0.
421 if (tid == 0) {
422 PerRegionTable::add_reference(from);
423 } else {
424 pt[tid-1]->seq_add_reference(from);
425 }
426 } else {
427 // Not expanded -- add to the base table.
428 PerRegionTable::add_reference(from);
429 }
430 }
431
432 void scrub(CardTableModRefBS* ctbs, BitMap* card_bm) {
433 assert(_par_tables == NULL, "Precondition");
434 PerRegionTable::scrub(ctbs, card_bm);
435 }
436
437 size_t mem_size() const {
438 size_t res =
439 PerRegionTable::mem_size() + sizeof(this) - sizeof(PerRegionTable);
440 if (_par_tables != NULL) {
441 for (int i = 0; i < HeapRegionRemSet::num_par_rem_sets()-1; i++) {
442 res += _par_tables[i]->mem_size();
443 }
444 }
445 return res;
446 }
447
448 static size_t fl_mem_size() {
449 PosParPRT* cur = _free_list;
450 size_t res = 0;
451 while (cur != NULL) {
452 res += sizeof(PosParPRT);
453 cur = cur->next();
454 }
455 return res;
456 }
457
458 bool contains_reference(OopOrNarrowOopStar from) const {
459 if (PerRegionTable::contains_reference(from)) return true;
460 if (_par_tables != NULL) {
461 for (int i = 0; i < HeapRegionRemSet::num_par_rem_sets()-1; i++) {
462 if (_par_tables[i]->contains_reference(from)) return true;
463 }
464 }
465 return false;
466 }
467
468 static void par_contract_all();
469 };
470
471 void PosParPRT::par_contract_all() {
472 PosParPRT* hd = _par_expanded_list;
473 while (hd != NULL) {
474 PosParPRT* nxt = hd->next_par_expanded();
475 PosParPRT* res =
476 (PosParPRT*)
477 Atomic::cmpxchg_ptr(nxt, &_par_expanded_list, hd);
478 if (res == hd) {
479 // We claimed the right to contract this table.
480 hd->set_next_par_expanded(NULL);
481 hd->par_contract();
482 hd = _par_expanded_list;
483 } else {
484 hd = res;
485 }
486 }
487 }
488
489 PosParPRT* PosParPRT::_free_list = NULL;
490 PosParPRT* PosParPRT::_par_expanded_list = NULL;
491
492 jint OtherRegionsTable::_cache_probes = 0;
493 jint OtherRegionsTable::_cache_hits = 0;
494
495 size_t OtherRegionsTable::_max_fine_entries = 0;
496 size_t OtherRegionsTable::_mod_max_fine_entries_mask = 0;
497 #if SAMPLE_FOR_EVICTION
498 size_t OtherRegionsTable::_fine_eviction_stride = 0;
499 size_t OtherRegionsTable::_fine_eviction_sample_size = 0;
500 #endif
501
502 OtherRegionsTable::OtherRegionsTable(HeapRegion* hr) :
503 _g1h(G1CollectedHeap::heap()),
504 _m(Mutex::leaf, "An OtherRegionsTable lock", true),
505 _hr(hr),
506 _coarse_map(G1CollectedHeap::heap()->max_regions(),
507 false /* in-resource-area */),
508 _fine_grain_regions(NULL),
509 _n_fine_entries(0), _n_coarse_entries(0),
510 #if SAMPLE_FOR_EVICTION
511 _fine_eviction_start(0),
512 #endif
513 _sparse_table(hr)
514 {
515 typedef PosParPRT* PosParPRTPtr;
516 if (_max_fine_entries == 0) {
517 assert(_mod_max_fine_entries_mask == 0, "Both or none.");
518 size_t max_entries_log = (size_t)log2_long((jlong)G1RSetRegionEntries);
519 _max_fine_entries = (size_t)(1 << max_entries_log);
520 _mod_max_fine_entries_mask = _max_fine_entries - 1;
521 #if SAMPLE_FOR_EVICTION
522 assert(_fine_eviction_sample_size == 0
523 && _fine_eviction_stride == 0, "All init at same time.");
524 _fine_eviction_sample_size = MAX2((size_t)4, max_entries_log);
525 _fine_eviction_stride = _max_fine_entries / _fine_eviction_sample_size;
526 #endif
527 }
528 _fine_grain_regions = new PosParPRTPtr[_max_fine_entries];
529 if (_fine_grain_regions == NULL)
530 vm_exit_out_of_memory(sizeof(void*)*_max_fine_entries,
531 "Failed to allocate _fine_grain_entries.");
532 for (size_t i = 0; i < _max_fine_entries; i++) {
533 _fine_grain_regions[i] = NULL;
534 }
535 }
536
537 int** OtherRegionsTable::_from_card_cache = NULL;
538 size_t OtherRegionsTable::_from_card_cache_max_regions = 0;
539 size_t OtherRegionsTable::_from_card_cache_mem_size = 0;
540
541 void OtherRegionsTable::init_from_card_cache(size_t max_regions) {
542 _from_card_cache_max_regions = max_regions;
543
544 int n_par_rs = HeapRegionRemSet::num_par_rem_sets();
545 _from_card_cache = NEW_C_HEAP_ARRAY(int*, n_par_rs);
546 for (int i = 0; i < n_par_rs; i++) {
547 _from_card_cache[i] = NEW_C_HEAP_ARRAY(int, max_regions);
548 for (size_t j = 0; j < max_regions; j++) {
549 _from_card_cache[i][j] = -1; // An invalid value.
550 }
551 }
552 _from_card_cache_mem_size = n_par_rs * max_regions * sizeof(int);
553 }
554
555 void OtherRegionsTable::shrink_from_card_cache(size_t new_n_regs) {
556 for (int i = 0; i < HeapRegionRemSet::num_par_rem_sets(); i++) {
557 assert(new_n_regs <= _from_card_cache_max_regions, "Must be within max.");
558 for (size_t j = new_n_regs; j < _from_card_cache_max_regions; j++) {
559 _from_card_cache[i][j] = -1; // An invalid value.
560 }
561 }
562 }
563
564 #ifndef PRODUCT
565 void OtherRegionsTable::print_from_card_cache() {
566 for (int i = 0; i < HeapRegionRemSet::num_par_rem_sets(); i++) {
567 for (size_t j = 0; j < _from_card_cache_max_regions; j++) {
568 gclog_or_tty->print_cr("_from_card_cache[%d][%d] = %d.",
569 i, j, _from_card_cache[i][j]);
570 }
571 }
572 }
573 #endif
574
575 void OtherRegionsTable::add_reference(OopOrNarrowOopStar from, int tid) {
576 size_t cur_hrs_ind = hr()->hrs_index();
577
578 #if HRRS_VERBOSE
579 gclog_or_tty->print_cr("ORT::add_reference_work(" PTR_FORMAT "->" PTR_FORMAT ").",
580 from,
581 UseCompressedOops
582 ? oopDesc::load_decode_heap_oop((narrowOop*)from)
583 : oopDesc::load_decode_heap_oop((oop*)from));
584 #endif
585
586 int from_card = (int)(uintptr_t(from) >> CardTableModRefBS::card_shift);
587
588 #if HRRS_VERBOSE
589 gclog_or_tty->print_cr("Table for [" PTR_FORMAT "...): card %d (cache = %d)",
590 hr()->bottom(), from_card,
591 _from_card_cache[tid][cur_hrs_ind]);
592 #endif
593
594 #define COUNT_CACHE 0
595 #if COUNT_CACHE
596 jint p = Atomic::add(1, &_cache_probes);
597 if ((p % 10000) == 0) {
598 jint hits = _cache_hits;
599 gclog_or_tty->print_cr("%d/%d = %5.2f%% RS cache hits.",
600 _cache_hits, p, 100.0* (float)hits/(float)p);
601 }
602 #endif
603 if (from_card == _from_card_cache[tid][cur_hrs_ind]) {
604 #if HRRS_VERBOSE
605 gclog_or_tty->print_cr(" from-card cache hit.");
606 #endif
607 #if COUNT_CACHE
608 Atomic::inc(&_cache_hits);
609 #endif
610 assert(contains_reference(from), "We just added it!");
611 return;
612 } else {
613 _from_card_cache[tid][cur_hrs_ind] = from_card;
614 }
615
616 // Note that this may be a continued H region.
617 HeapRegion* from_hr = _g1h->heap_region_containing_raw(from);
618 RegionIdx_t from_hrs_ind = (RegionIdx_t) from_hr->hrs_index();
619
620 // If the region is already coarsened, return.
621 if (_coarse_map.at(from_hrs_ind)) {
622 #if HRRS_VERBOSE
623 gclog_or_tty->print_cr(" coarse map hit.");
624 #endif
625 assert(contains_reference(from), "We just added it!");
626 return;
627 }
628
629 // Otherwise find a per-region table to add it to.
630 size_t ind = from_hrs_ind & _mod_max_fine_entries_mask;
631 PosParPRT* prt = find_region_table(ind, from_hr);
632 if (prt == NULL) {
633 MutexLockerEx x(&_m, Mutex::_no_safepoint_check_flag);
634 // Confirm that it's really not there...
635 prt = find_region_table(ind, from_hr);
636 if (prt == NULL) {
637
638 uintptr_t from_hr_bot_card_index =
639 uintptr_t(from_hr->bottom())
640 >> CardTableModRefBS::card_shift;
641 CardIdx_t card_index = from_card - from_hr_bot_card_index;
642 assert(0 <= card_index && (size_t)card_index < HeapRegion::CardsPerRegion,
643 "Must be in range.");
644 if (G1HRRSUseSparseTable &&
645 _sparse_table.add_card(from_hrs_ind, card_index)) {
646 if (G1RecordHRRSOops) {
647 HeapRegionRemSet::record(hr(), from);
648 #if HRRS_VERBOSE
649 gclog_or_tty->print(" Added card " PTR_FORMAT " to region "
650 "[" PTR_FORMAT "...) for ref " PTR_FORMAT ".\n",
651 align_size_down(uintptr_t(from),
652 CardTableModRefBS::card_size),
653 hr()->bottom(), from);
654 #endif
655 }
656 #if HRRS_VERBOSE
657 gclog_or_tty->print_cr(" added card to sparse table.");
658 #endif
659 assert(contains_reference_locked(from), "We just added it!");
660 return;
661 } else {
662 #if HRRS_VERBOSE
663 gclog_or_tty->print_cr(" [tid %d] sparse table entry "
664 "overflow(f: %d, t: %d)",
665 tid, from_hrs_ind, cur_hrs_ind);
666 #endif
667 }
668
669 if (_n_fine_entries == _max_fine_entries) {
670 prt = delete_region_table();
671 } else {
672 prt = PosParPRT::alloc(from_hr);
673 }
674 prt->init(from_hr);
675
676 PosParPRT* first_prt = _fine_grain_regions[ind];
677 prt->set_next(first_prt); // XXX Maybe move to init?
678 _fine_grain_regions[ind] = prt;
679 _n_fine_entries++;
680
681 if (G1HRRSUseSparseTable) {
682 // Transfer from sparse to fine-grain.
683 SparsePRTEntry *sprt_entry = _sparse_table.get_entry(from_hrs_ind);
684 assert(sprt_entry != NULL, "There should have been an entry");
685 for (int i = 0; i < SparsePRTEntry::cards_num(); i++) {
686 CardIdx_t c = sprt_entry->card(i);
687 if (c != SparsePRTEntry::NullEntry) {
688 prt->add_card(c);
689 }
690 }
691 // Now we can delete the sparse entry.
692 bool res = _sparse_table.delete_entry(from_hrs_ind);
693 assert(res, "It should have been there.");
694 }
695 }
696 assert(prt != NULL && prt->hr() == from_hr, "consequence");
697 }
698 // Note that we can't assert "prt->hr() == from_hr", because of the
699 // possibility of concurrent reuse. But see head comment of
700 // OtherRegionsTable for why this is OK.
701 assert(prt != NULL, "Inv");
702
703 if (prt->should_expand(tid)) {
704 MutexLockerEx x(&_m, Mutex::_no_safepoint_check_flag);
705 HeapRegion* prt_hr = prt->hr();
706 if (prt_hr == from_hr) {
707 // Make sure the table still corresponds to the same region
708 prt->par_expand();
709 prt->add_reference(from, tid);
710 }
711 // else: The table has been concurrently coarsened, evicted, and
712 // the table data structure re-used for another table. So, we
713 // don't need to add the reference any more given that the table
714 // has been coarsened and the whole region will be scanned anyway.
715 } else {
716 prt->add_reference(from, tid);
717 }
718 if (G1RecordHRRSOops) {
719 HeapRegionRemSet::record(hr(), from);
720 #if HRRS_VERBOSE
721 gclog_or_tty->print("Added card " PTR_FORMAT " to region "
722 "[" PTR_FORMAT "...) for ref " PTR_FORMAT ".\n",
723 align_size_down(uintptr_t(from),
724 CardTableModRefBS::card_size),
725 hr()->bottom(), from);
726 #endif
727 }
728 assert(contains_reference(from), "We just added it!");
729 }
730
731 PosParPRT*
732 OtherRegionsTable::find_region_table(size_t ind, HeapRegion* hr) const {
733 assert(0 <= ind && ind < _max_fine_entries, "Preconditions.");
734 PosParPRT* prt = _fine_grain_regions[ind];
735 while (prt != NULL && prt->hr() != hr) {
736 prt = prt->next();
737 }
738 // Loop postcondition is the method postcondition.
739 return prt;
740 }
741
742
743 #define DRT_CENSUS 0
744
745 #if DRT_CENSUS
746 static const int HistoSize = 6;
747 static int global_histo[HistoSize] = { 0, 0, 0, 0, 0, 0 };
748 static int coarsenings = 0;
749 static int occ_sum = 0;
750 #endif
751
752 jint OtherRegionsTable::_n_coarsenings = 0;
753
754 PosParPRT* OtherRegionsTable::delete_region_table() {
755 #if DRT_CENSUS
756 int histo[HistoSize] = { 0, 0, 0, 0, 0, 0 };
757 const int histo_limits[] = { 1, 4, 16, 64, 256, 2048 };
758 #endif
759
760 assert(_m.owned_by_self(), "Precondition");
761 assert(_n_fine_entries == _max_fine_entries, "Precondition");
762 PosParPRT* max = NULL;
763 jint max_occ = 0;
764 PosParPRT** max_prev;
765 size_t max_ind;
766
767 #if SAMPLE_FOR_EVICTION
768 size_t i = _fine_eviction_start;
769 for (size_t k = 0; k < _fine_eviction_sample_size; k++) {
770 size_t ii = i;
771 // Make sure we get a non-NULL sample.
772 while (_fine_grain_regions[ii] == NULL) {
773 ii++;
774 if (ii == _max_fine_entries) ii = 0;
775 guarantee(ii != i, "We must find one.");
776 }
777 PosParPRT** prev = &_fine_grain_regions[ii];
778 PosParPRT* cur = *prev;
779 while (cur != NULL) {
780 jint cur_occ = cur->occupied();
781 if (max == NULL || cur_occ > max_occ) {
782 max = cur;
783 max_prev = prev;
784 max_ind = i;
785 max_occ = cur_occ;
786 }
787 prev = cur->next_addr();
788 cur = cur->next();
789 }
790 i = i + _fine_eviction_stride;
791 if (i >= _n_fine_entries) i = i - _n_fine_entries;
792 }
793 _fine_eviction_start++;
794 if (_fine_eviction_start >= _n_fine_entries)
795 _fine_eviction_start -= _n_fine_entries;
796 #else
797 for (int i = 0; i < _max_fine_entries; i++) {
798 PosParPRT** prev = &_fine_grain_regions[i];
799 PosParPRT* cur = *prev;
800 while (cur != NULL) {
801 jint cur_occ = cur->occupied();
802 #if DRT_CENSUS
803 for (int k = 0; k < HistoSize; k++) {
804 if (cur_occ <= histo_limits[k]) {
805 histo[k]++; global_histo[k]++; break;
806 }
807 }
808 #endif
809 if (max == NULL || cur_occ > max_occ) {
810 max = cur;
811 max_prev = prev;
812 max_ind = i;
813 max_occ = cur_occ;
814 }
815 prev = cur->next_addr();
816 cur = cur->next();
817 }
818 }
819 #endif
820 // XXX
821 guarantee(max != NULL, "Since _n_fine_entries > 0");
822 #if DRT_CENSUS
823 gclog_or_tty->print_cr("In a coarsening: histo of occs:");
824 for (int k = 0; k < HistoSize; k++) {
825 gclog_or_tty->print_cr(" <= %4d: %5d.", histo_limits[k], histo[k]);
826 }
827 coarsenings++;
828 occ_sum += max_occ;
829 if ((coarsenings % 100) == 0) {
830 gclog_or_tty->print_cr("\ncoarsenings = %d; global summary:", coarsenings);
831 for (int k = 0; k < HistoSize; k++) {
832 gclog_or_tty->print_cr(" <= %4d: %5d.", histo_limits[k], global_histo[k]);
833 }
834 gclog_or_tty->print_cr("Avg occ of deleted region = %6.2f.",
835 (float)occ_sum/(float)coarsenings);
836 }
837 #endif
838
839 // Set the corresponding coarse bit.
840 size_t max_hrs_index = max->hr()->hrs_index();
841 if (!_coarse_map.at(max_hrs_index)) {
842 _coarse_map.at_put(max_hrs_index, true);
843 _n_coarse_entries++;
844 #if 0
845 gclog_or_tty->print("Coarsened entry in region [" PTR_FORMAT "...] "
846 "for region [" PTR_FORMAT "...] (%d coarse entries).\n",
847 hr()->bottom(),
848 max->hr()->bottom(),
849 _n_coarse_entries);
850 #endif
851 }
852
853 // Unsplice.
854 *max_prev = max->next();
855 Atomic::inc(&_n_coarsenings);
856 _n_fine_entries--;
857 return max;
858 }
859
860
861 // At present, this must be called stop-world single-threaded.
862 void OtherRegionsTable::scrub(CardTableModRefBS* ctbs,
863 BitMap* region_bm, BitMap* card_bm) {
864 // First eliminated garbage regions from the coarse map.
865 if (G1RSScrubVerbose)
866 gclog_or_tty->print_cr("Scrubbing region "SIZE_FORMAT":",
867 hr()->hrs_index());
868
869 assert(_coarse_map.size() == region_bm->size(), "Precondition");
870 if (G1RSScrubVerbose)
871 gclog_or_tty->print(" Coarse map: before = %d...", _n_coarse_entries);
872 _coarse_map.set_intersection(*region_bm);
873 _n_coarse_entries = _coarse_map.count_one_bits();
874 if (G1RSScrubVerbose)
875 gclog_or_tty->print_cr(" after = %d.", _n_coarse_entries);
876
877 // Now do the fine-grained maps.
878 for (size_t i = 0; i < _max_fine_entries; i++) {
879 PosParPRT* cur = _fine_grain_regions[i];
880 PosParPRT** prev = &_fine_grain_regions[i];
881 while (cur != NULL) {
882 PosParPRT* nxt = cur->next();
883 // If the entire region is dead, eliminate.
884 if (G1RSScrubVerbose)
885 gclog_or_tty->print_cr(" For other region "SIZE_FORMAT":",
886 cur->hr()->hrs_index());
887 if (!region_bm->at(cur->hr()->hrs_index())) {
888 *prev = nxt;
889 cur->set_next(NULL);
890 _n_fine_entries--;
891 if (G1RSScrubVerbose)
892 gclog_or_tty->print_cr(" deleted via region map.");
893 PosParPRT::free(cur);
894 } else {
895 // Do fine-grain elimination.
896 if (G1RSScrubVerbose)
897 gclog_or_tty->print(" occ: before = %4d.", cur->occupied());
898 cur->scrub(ctbs, card_bm);
899 if (G1RSScrubVerbose)
900 gclog_or_tty->print_cr(" after = %4d.", cur->occupied());
901 // Did that empty the table completely?
902 if (cur->occupied() == 0) {
903 *prev = nxt;
904 cur->set_next(NULL);
905 _n_fine_entries--;
906 PosParPRT::free(cur);
907 } else {
908 prev = cur->next_addr();
909 }
910 }
911 cur = nxt;
912 }
913 }
914 // Since we may have deleted a from_card_cache entry from the RS, clear
915 // the FCC.
916 clear_fcc();
917 }
918
919
920 size_t OtherRegionsTable::occupied() const {
921 // Cast away const in this case.
922 MutexLockerEx x((Mutex*)&_m, Mutex::_no_safepoint_check_flag);
923 size_t sum = occ_fine();
924 sum += occ_sparse();
925 sum += occ_coarse();
926 return sum;
927 }
928
929 size_t OtherRegionsTable::occ_fine() const {
930 size_t sum = 0;
931 for (size_t i = 0; i < _max_fine_entries; i++) {
932 PosParPRT* cur = _fine_grain_regions[i];
933 while (cur != NULL) {
934 sum += cur->occupied();
935 cur = cur->next();
936 }
937 }
938 return sum;
939 }
940
941 size_t OtherRegionsTable::occ_coarse() const {
942 return (_n_coarse_entries * HeapRegion::CardsPerRegion);
943 }
944
945 size_t OtherRegionsTable::occ_sparse() const {
946 return _sparse_table.occupied();
947 }
948
949 size_t OtherRegionsTable::mem_size() const {
950 // Cast away const in this case.
951 MutexLockerEx x((Mutex*)&_m, Mutex::_no_safepoint_check_flag);
952 size_t sum = 0;
953 for (size_t i = 0; i < _max_fine_entries; i++) {
954 PosParPRT* cur = _fine_grain_regions[i];
955 while (cur != NULL) {
956 sum += cur->mem_size();
957 cur = cur->next();
958 }
959 }
960 sum += (sizeof(PosParPRT*) * _max_fine_entries);
961 sum += (_coarse_map.size_in_words() * HeapWordSize);
962 sum += (_sparse_table.mem_size());
963 sum += sizeof(*this) - sizeof(_sparse_table); // Avoid double counting above.
964 return sum;
965 }
966
967 size_t OtherRegionsTable::static_mem_size() {
968 return _from_card_cache_mem_size;
969 }
970
971 size_t OtherRegionsTable::fl_mem_size() {
972 return PerRegionTable::fl_mem_size() + PosParPRT::fl_mem_size();
973 }
974
975 void OtherRegionsTable::clear_fcc() {
976 for (int i = 0; i < HeapRegionRemSet::num_par_rem_sets(); i++) {
977 _from_card_cache[i][hr()->hrs_index()] = -1;
978 }
979 }
980
981 void OtherRegionsTable::clear() {
982 MutexLockerEx x(&_m, Mutex::_no_safepoint_check_flag);
983 for (size_t i = 0; i < _max_fine_entries; i++) {
984 PosParPRT* cur = _fine_grain_regions[i];
985 while (cur != NULL) {
986 PosParPRT* nxt = cur->next();
987 PosParPRT::free(cur);
988 cur = nxt;
989 }
990 _fine_grain_regions[i] = NULL;
991 }
992 _sparse_table.clear();
993 _coarse_map.clear();
994 _n_fine_entries = 0;
995 _n_coarse_entries = 0;
996
997 clear_fcc();
998 }
999
1000 void OtherRegionsTable::clear_incoming_entry(HeapRegion* from_hr) {
1001 MutexLockerEx x(&_m, Mutex::_no_safepoint_check_flag);
1002 size_t hrs_ind = from_hr->hrs_index();
1003 size_t ind = hrs_ind & _mod_max_fine_entries_mask;
1004 if (del_single_region_table(ind, from_hr)) {
1005 assert(!_coarse_map.at(hrs_ind), "Inv");
1006 } else {
1007 _coarse_map.par_at_put(hrs_ind, 0);
1008 }
1009 // Check to see if any of the fcc entries come from here.
1010 size_t hr_ind = hr()->hrs_index();
1011 for (int tid = 0; tid < HeapRegionRemSet::num_par_rem_sets(); tid++) {
1012 int fcc_ent = _from_card_cache[tid][hr_ind];
1013 if (fcc_ent != -1) {
1014 HeapWord* card_addr = (HeapWord*)
1015 (uintptr_t(fcc_ent) << CardTableModRefBS::card_shift);
1016 if (hr()->is_in_reserved(card_addr)) {
1017 // Clear the from card cache.
1018 _from_card_cache[tid][hr_ind] = -1;
1019 }
1020 }
1021 }
1022 }
1023
1024 bool OtherRegionsTable::del_single_region_table(size_t ind,
1025 HeapRegion* hr) {
1026 assert(0 <= ind && ind < _max_fine_entries, "Preconditions.");
1027 PosParPRT** prev_addr = &_fine_grain_regions[ind];
1028 PosParPRT* prt = *prev_addr;
1029 while (prt != NULL && prt->hr() != hr) {
1030 prev_addr = prt->next_addr();
1031 prt = prt->next();
1032 }
1033 if (prt != NULL) {
1034 assert(prt->hr() == hr, "Loop postcondition.");
1035 *prev_addr = prt->next();
1036 PosParPRT::free(prt);
1037 _n_fine_entries--;
1038 return true;
1039 } else {
1040 return false;
1041 }
1042 }
1043
1044 bool OtherRegionsTable::contains_reference(OopOrNarrowOopStar from) const {
1045 // Cast away const in this case.
1046 MutexLockerEx x((Mutex*)&_m, Mutex::_no_safepoint_check_flag);
1047 return contains_reference_locked(from);
1048 }
1049
1050 bool OtherRegionsTable::contains_reference_locked(OopOrNarrowOopStar from) const {
1051 HeapRegion* hr = _g1h->heap_region_containing_raw(from);
1052 if (hr == NULL) return false;
1053 RegionIdx_t hr_ind = (RegionIdx_t) hr->hrs_index();
1054 // Is this region in the coarse map?
1055 if (_coarse_map.at(hr_ind)) return true;
1056
1057 PosParPRT* prt = find_region_table(hr_ind & _mod_max_fine_entries_mask,
1058 hr);
1059 if (prt != NULL) {
1060 return prt->contains_reference(from);
1061
1062 } else {
1063 uintptr_t from_card =
1064 (uintptr_t(from) >> CardTableModRefBS::card_shift);
1065 uintptr_t hr_bot_card_index =
1066 uintptr_t(hr->bottom()) >> CardTableModRefBS::card_shift;
1067 assert(from_card >= hr_bot_card_index, "Inv");
1068 CardIdx_t card_index = from_card - hr_bot_card_index;
1069 assert(0 <= card_index && (size_t)card_index < HeapRegion::CardsPerRegion,
1070 "Must be in range.");
1071 return _sparse_table.contains_card(hr_ind, card_index);
1072 }
1073
1074
1075 }
1076
1077 void
1078 OtherRegionsTable::do_cleanup_work(HRRSCleanupTask* hrrs_cleanup_task) {
1079 _sparse_table.do_cleanup_work(hrrs_cleanup_task);
1080 }
1081
1082 // Determines how many threads can add records to an rset in parallel.
1083 // This can be done by either mutator threads together with the
1084 // concurrent refinement threads or GC threads.
1085 int HeapRegionRemSet::num_par_rem_sets() {
1086 return (int)MAX2(DirtyCardQueueSet::num_par_ids() + ConcurrentG1Refine::thread_num(), ParallelGCThreads);
1087 }
1088
1089 HeapRegionRemSet::HeapRegionRemSet(G1BlockOffsetSharedArray* bosa,
1090 HeapRegion* hr)
1091 : _bosa(bosa), _other_regions(hr) {
1092 reset_for_par_iteration();
1093 }
1094
1095 void HeapRegionRemSet::setup_remset_size() {
1096 // Setup sparse and fine-grain tables sizes.
1097 // table_size = base * (log(region_size / 1M) + 1)
1098 int region_size_log_mb = MAX2((int)HeapRegion::LogOfHRGrainBytes - (int)LOG_M, 0);
1099 if (FLAG_IS_DEFAULT(G1RSetSparseRegionEntries)) {
1100 G1RSetSparseRegionEntries = G1RSetSparseRegionEntriesBase * (region_size_log_mb + 1);
1101 }
1102 if (FLAG_IS_DEFAULT(G1RSetRegionEntries)) {
1103 G1RSetRegionEntries = G1RSetRegionEntriesBase * (region_size_log_mb + 1);
1104 }
1105 guarantee(G1RSetSparseRegionEntries > 0 && G1RSetRegionEntries > 0 , "Sanity");
1106 }
1107
1108 bool HeapRegionRemSet::claim_iter() {
1109 if (_iter_state != Unclaimed) return false;
1110 jint res = Atomic::cmpxchg(Claimed, (jint*)(&_iter_state), Unclaimed);
1111 return (res == Unclaimed);
1112 }
1113
1114 void HeapRegionRemSet::set_iter_complete() {
1115 _iter_state = Complete;
1116 }
1117
1118 bool HeapRegionRemSet::iter_is_complete() {
1119 return _iter_state == Complete;
1120 }
1121
1122 void HeapRegionRemSet::init_iterator(HeapRegionRemSetIterator* iter) const {
1123 iter->initialize(this);
1124 }
1125
1126 #ifndef PRODUCT
1127 void HeapRegionRemSet::print() const {
1128 HeapRegionRemSetIterator iter;
1129 init_iterator(&iter);
1130 size_t card_index;
1131 while (iter.has_next(card_index)) {
1132 HeapWord* card_start =
1133 G1CollectedHeap::heap()->bot_shared()->address_for_index(card_index);
1134 gclog_or_tty->print_cr(" Card " PTR_FORMAT, card_start);
1135 }
1136 // XXX
1137 if (iter.n_yielded() != occupied()) {
1138 gclog_or_tty->print_cr("Yielded disagrees with occupied:");
1139 gclog_or_tty->print_cr(" %6d yielded (%6d coarse, %6d fine).",
1140 iter.n_yielded(),
1141 iter.n_yielded_coarse(), iter.n_yielded_fine());
1142 gclog_or_tty->print_cr(" %6d occ (%6d coarse, %6d fine).",
1143 occupied(), occ_coarse(), occ_fine());
1144 }
1145 guarantee(iter.n_yielded() == occupied(),
1146 "We should have yielded all the represented cards.");
1147 }
1148 #endif
1149
1150 void HeapRegionRemSet::cleanup() {
1151 SparsePRT::cleanup_all();
1152 }
1153
1154 void HeapRegionRemSet::par_cleanup() {
1155 PosParPRT::par_contract_all();
1156 }
1157
1158 void HeapRegionRemSet::clear() {
1159 _other_regions.clear();
1160 assert(occupied() == 0, "Should be clear.");
1161 reset_for_par_iteration();
1162 }
1163
1164 void HeapRegionRemSet::reset_for_par_iteration() {
1165 _iter_state = Unclaimed;
1166 _iter_claimed = 0;
1167 // It's good to check this to make sure that the two methods are in sync.
1168 assert(verify_ready_for_par_iteration(), "post-condition");
1169 }
1170
1171 void HeapRegionRemSet::scrub(CardTableModRefBS* ctbs,
1172 BitMap* region_bm, BitMap* card_bm) {
1173 _other_regions.scrub(ctbs, region_bm, card_bm);
1174 }
1175
1176 //-------------------- Iteration --------------------
1177
1178 HeapRegionRemSetIterator::
1179 HeapRegionRemSetIterator() :
1180 _hrrs(NULL),
1181 _g1h(G1CollectedHeap::heap()),
1182 _bosa(NULL),
1183 _sparse_iter() { }
1184
1185 void HeapRegionRemSetIterator::initialize(const HeapRegionRemSet* hrrs) {
1186 _hrrs = hrrs;
1187 _coarse_map = &_hrrs->_other_regions._coarse_map;
1188 _fine_grain_regions = _hrrs->_other_regions._fine_grain_regions;
1189 _bosa = _hrrs->bosa();
1190
1191 _is = Sparse;
1192 // Set these values so that we increment to the first region.
1193 _coarse_cur_region_index = -1;
1194 _coarse_cur_region_cur_card = (HeapRegion::CardsPerRegion-1);
1195
1196 _cur_region_cur_card = 0;
1197
1198 _fine_array_index = -1;
1199 _fine_cur_prt = NULL;
1200
1201 _n_yielded_coarse = 0;
1202 _n_yielded_fine = 0;
1203 _n_yielded_sparse = 0;
1204
1205 _sparse_iter.init(&hrrs->_other_regions._sparse_table);
1206 }
1207
1208 bool HeapRegionRemSetIterator::coarse_has_next(size_t& card_index) {
1209 if (_hrrs->_other_regions._n_coarse_entries == 0) return false;
1210 // Go to the next card.
1211 _coarse_cur_region_cur_card++;
1212 // Was the last the last card in the current region?
1213 if (_coarse_cur_region_cur_card == HeapRegion::CardsPerRegion) {
1214 // Yes: find the next region. This may leave _coarse_cur_region_index
1215 // Set to the last index, in which case there are no more coarse
1216 // regions.
1217 _coarse_cur_region_index =
1218 (int) _coarse_map->get_next_one_offset(_coarse_cur_region_index + 1);
1219 if ((size_t)_coarse_cur_region_index < _coarse_map->size()) {
1220 _coarse_cur_region_cur_card = 0;
1221 HeapWord* r_bot =
1222 _g1h->region_at(_coarse_cur_region_index)->bottom();
1223 _cur_region_card_offset = _bosa->index_for(r_bot);
1224 } else {
1225 return false;
1226 }
1227 }
1228 // If we didn't return false above, then we can yield a card.
1229 card_index = _cur_region_card_offset + _coarse_cur_region_cur_card;
1230 return true;
1231 }
1232
1233 void HeapRegionRemSetIterator::fine_find_next_non_null_prt() {
1234 // Otherwise, find the next bucket list in the array.
1235 _fine_array_index++;
1236 while (_fine_array_index < (int) OtherRegionsTable::_max_fine_entries) {
1237 _fine_cur_prt = _fine_grain_regions[_fine_array_index];
1238 if (_fine_cur_prt != NULL) return;
1239 else _fine_array_index++;
1240 }
1241 assert(_fine_cur_prt == NULL, "Loop post");
1242 }
1243
1244 bool HeapRegionRemSetIterator::fine_has_next(size_t& card_index) {
1245 if (fine_has_next()) {
1246 _cur_region_cur_card =
1247 _fine_cur_prt->_bm.get_next_one_offset(_cur_region_cur_card + 1);
1248 }
1249 while (!fine_has_next()) {
1250 if (_cur_region_cur_card == (size_t) HeapRegion::CardsPerRegion) {
1251 _cur_region_cur_card = 0;
1252 _fine_cur_prt = _fine_cur_prt->next();
1253 }
1254 if (_fine_cur_prt == NULL) {
1255 fine_find_next_non_null_prt();
1256 if (_fine_cur_prt == NULL) return false;
1257 }
1258 assert(_fine_cur_prt != NULL && _cur_region_cur_card == 0,
1259 "inv.");
1260 HeapWord* r_bot =
1261 _fine_cur_prt->hr()->bottom();
1262 _cur_region_card_offset = _bosa->index_for(r_bot);
1263 _cur_region_cur_card = _fine_cur_prt->_bm.get_next_one_offset(0);
1264 }
1265 assert(fine_has_next(), "Or else we exited the loop via the return.");
1266 card_index = _cur_region_card_offset + _cur_region_cur_card;
1267 return true;
1268 }
1269
1270 bool HeapRegionRemSetIterator::fine_has_next() {
1271 return
1272 _fine_cur_prt != NULL &&
1273 _cur_region_cur_card < HeapRegion::CardsPerRegion;
1274 }
1275
1276 bool HeapRegionRemSetIterator::has_next(size_t& card_index) {
1277 switch (_is) {
1278 case Sparse:
1279 if (_sparse_iter.has_next(card_index)) {
1280 _n_yielded_sparse++;
1281 return true;
1282 }
1283 // Otherwise, deliberate fall-through
1284 _is = Fine;
1285 case Fine:
1286 if (fine_has_next(card_index)) {
1287 _n_yielded_fine++;
1288 return true;
1289 }
1290 // Otherwise, deliberate fall-through
1291 _is = Coarse;
1292 case Coarse:
1293 if (coarse_has_next(card_index)) {
1294 _n_yielded_coarse++;
1295 return true;
1296 }
1297 // Otherwise...
1298 break;
1299 }
1300 assert(ParallelGCThreads > 1 ||
1301 n_yielded() == _hrrs->occupied(),
1302 "Should have yielded all the cards in the rem set "
1303 "(in the non-par case).");
1304 return false;
1305 }
1306
1307
1308
1309 OopOrNarrowOopStar* HeapRegionRemSet::_recorded_oops = NULL;
1310 HeapWord** HeapRegionRemSet::_recorded_cards = NULL;
1311 HeapRegion** HeapRegionRemSet::_recorded_regions = NULL;
1312 int HeapRegionRemSet::_n_recorded = 0;
1313
1314 HeapRegionRemSet::Event* HeapRegionRemSet::_recorded_events = NULL;
1315 int* HeapRegionRemSet::_recorded_event_index = NULL;
1316 int HeapRegionRemSet::_n_recorded_events = 0;
1317
1318 void HeapRegionRemSet::record(HeapRegion* hr, OopOrNarrowOopStar f) {
1319 if (_recorded_oops == NULL) {
1320 assert(_n_recorded == 0
1321 && _recorded_cards == NULL
1322 && _recorded_regions == NULL,
1323 "Inv");
1324 _recorded_oops = NEW_C_HEAP_ARRAY(OopOrNarrowOopStar, MaxRecorded);
1325 _recorded_cards = NEW_C_HEAP_ARRAY(HeapWord*, MaxRecorded);
1326 _recorded_regions = NEW_C_HEAP_ARRAY(HeapRegion*, MaxRecorded);
1327 }
1328 if (_n_recorded == MaxRecorded) {
1329 gclog_or_tty->print_cr("Filled up 'recorded' (%d).", MaxRecorded);
1330 } else {
1331 _recorded_cards[_n_recorded] =
1332 (HeapWord*)align_size_down(uintptr_t(f),
1333 CardTableModRefBS::card_size);
1334 _recorded_oops[_n_recorded] = f;
1335 _recorded_regions[_n_recorded] = hr;
1336 _n_recorded++;
1337 }
1338 }
1339
1340 void HeapRegionRemSet::record_event(Event evnt) {
1341 if (!G1RecordHRRSEvents) return;
1342
1343 if (_recorded_events == NULL) {
1344 assert(_n_recorded_events == 0
1345 && _recorded_event_index == NULL,
1346 "Inv");
1347 _recorded_events = NEW_C_HEAP_ARRAY(Event, MaxRecordedEvents);
1348 _recorded_event_index = NEW_C_HEAP_ARRAY(int, MaxRecordedEvents);
1349 }
1350 if (_n_recorded_events == MaxRecordedEvents) {
1351 gclog_or_tty->print_cr("Filled up 'recorded_events' (%d).", MaxRecordedEvents);
1352 } else {
1353 _recorded_events[_n_recorded_events] = evnt;
1354 _recorded_event_index[_n_recorded_events] = _n_recorded;
1355 _n_recorded_events++;
1356 }
1357 }
1358
1359 void HeapRegionRemSet::print_event(outputStream* str, Event evnt) {
1360 switch (evnt) {
1361 case Event_EvacStart:
1362 str->print("Evac Start");
1363 break;
1364 case Event_EvacEnd:
1365 str->print("Evac End");
1366 break;
1367 case Event_RSUpdateEnd:
1368 str->print("RS Update End");
1369 break;
1370 }
1371 }
1372
1373 void HeapRegionRemSet::print_recorded() {
1374 int cur_evnt = 0;
1375 Event cur_evnt_kind;
1376 int cur_evnt_ind = 0;
1377 if (_n_recorded_events > 0) {
1378 cur_evnt_kind = _recorded_events[cur_evnt];
1379 cur_evnt_ind = _recorded_event_index[cur_evnt];
1380 }
1381
1382 for (int i = 0; i < _n_recorded; i++) {
1383 while (cur_evnt < _n_recorded_events && i == cur_evnt_ind) {
1384 gclog_or_tty->print("Event: ");
1385 print_event(gclog_or_tty, cur_evnt_kind);
1386 gclog_or_tty->print_cr("");
1387 cur_evnt++;
1388 if (cur_evnt < MaxRecordedEvents) {
1389 cur_evnt_kind = _recorded_events[cur_evnt];
1390 cur_evnt_ind = _recorded_event_index[cur_evnt];
1391 }
1392 }
1393 gclog_or_tty->print("Added card " PTR_FORMAT " to region [" PTR_FORMAT "...]"
1394 " for ref " PTR_FORMAT ".\n",
1395 _recorded_cards[i], _recorded_regions[i]->bottom(),
1396 _recorded_oops[i]);
1397 }
1398 }
1399
1400 void HeapRegionRemSet::reset_for_cleanup_tasks() {
1401 SparsePRT::reset_for_cleanup_tasks();
1402 }
1403
1404 void HeapRegionRemSet::do_cleanup_work(HRRSCleanupTask* hrrs_cleanup_task) {
1405 _other_regions.do_cleanup_work(hrrs_cleanup_task);
1406 }
1407
1408 void
1409 HeapRegionRemSet::finish_cleanup_task(HRRSCleanupTask* hrrs_cleanup_task) {
1410 SparsePRT::finish_cleanup_task(hrrs_cleanup_task);
1411 }
1412
1413 #ifndef PRODUCT
1414 void HeapRegionRemSet::test() {
1415 os::sleep(Thread::current(), (jlong)5000, false);
1416 G1CollectedHeap* g1h = G1CollectedHeap::heap();
1417
1418 // Run with "-XX:G1LogRSetRegionEntries=2", so that 1 and 5 end up in same
1419 // hash bucket.
1420 HeapRegion* hr0 = g1h->region_at(0);
1421 HeapRegion* hr1 = g1h->region_at(1);
1422 HeapRegion* hr2 = g1h->region_at(5);
1423 HeapRegion* hr3 = g1h->region_at(6);
1424 HeapRegion* hr4 = g1h->region_at(7);
1425 HeapRegion* hr5 = g1h->region_at(8);
1426
1427 HeapWord* hr1_start = hr1->bottom();
1428 HeapWord* hr1_mid = hr1_start + HeapRegion::GrainWords/2;
1429 HeapWord* hr1_last = hr1->end() - 1;
1430
1431 HeapWord* hr2_start = hr2->bottom();
1432 HeapWord* hr2_mid = hr2_start + HeapRegion::GrainWords/2;
1433 HeapWord* hr2_last = hr2->end() - 1;
1434
1435 HeapWord* hr3_start = hr3->bottom();
1436 HeapWord* hr3_mid = hr3_start + HeapRegion::GrainWords/2;
1437 HeapWord* hr3_last = hr3->end() - 1;
1438
1439 HeapRegionRemSet* hrrs = hr0->rem_set();
1440
1441 // Make three references from region 0x101...
1442 hrrs->add_reference((OopOrNarrowOopStar)hr1_start);
1443 hrrs->add_reference((OopOrNarrowOopStar)hr1_mid);
1444 hrrs->add_reference((OopOrNarrowOopStar)hr1_last);
1445
1446 hrrs->add_reference((OopOrNarrowOopStar)hr2_start);
1447 hrrs->add_reference((OopOrNarrowOopStar)hr2_mid);
1448 hrrs->add_reference((OopOrNarrowOopStar)hr2_last);
1449
1450 hrrs->add_reference((OopOrNarrowOopStar)hr3_start);
1451 hrrs->add_reference((OopOrNarrowOopStar)hr3_mid);
1452 hrrs->add_reference((OopOrNarrowOopStar)hr3_last);
1453
1454 // Now cause a coarsening.
1455 hrrs->add_reference((OopOrNarrowOopStar)hr4->bottom());
1456 hrrs->add_reference((OopOrNarrowOopStar)hr5->bottom());
1457
1458 // Now, does iteration yield these three?
1459 HeapRegionRemSetIterator iter;
1460 hrrs->init_iterator(&iter);
1461 size_t sum = 0;
1462 size_t card_index;
1463 while (iter.has_next(card_index)) {
1464 HeapWord* card_start =
1465 G1CollectedHeap::heap()->bot_shared()->address_for_index(card_index);
1466 gclog_or_tty->print_cr(" Card " PTR_FORMAT ".", card_start);
1467 sum++;
1468 }
1469 guarantee(sum == 11 - 3 + 2048, "Failure");
1470 guarantee(sum == hrrs->occupied(), "Failure");
1471 }
1472 #endif