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 the table used to belong to a continues humongous region and is
147 // now reused for the corresponding start humongous region, we need to
148 // make sure that we detect this. Thus, we call is_in_reserved_raw()
149 // instead of just is_in_reserved() here.
150 if (loc_hr->is_in_reserved_raw(from)) {
151 size_t hw_offset = pointer_delta((HeapWord*)from, loc_hr->bottom());
152 CardIdx_t from_card = (CardIdx_t)
153 hw_offset >> (CardTableModRefBS::card_shift - LogHeapWordSize);
154
155 assert(0 <= from_card && (size_t)from_card < HeapRegion::CardsPerRegion,
156 "Must be in range.");
157 add_card_work(from_card, par);
158 }
159 }
160
161 public:
162
163 HeapRegion* hr() const { return _hr; }
164
165 #if PRT_COUNT_OCCUPIED
166 jint occupied() const {
167 // Overkill, but if we ever need it...
168 // guarantee(_occupied == _bm.count_one_bits(), "Check");
169 return _occupied;
170 }
171 #else
172 jint occupied() const {
173 return _bm.count_one_bits();
174 }
175 #endif
176
177 void init(HeapRegion* hr) {
178 _hr = hr;
179 #if PRT_COUNT_OCCUPIED
180 _occupied = 0;
181 #endif
182 _bm.clear();
183 }
184
185 void add_reference(OopOrNarrowOopStar from) {
186 add_reference_work(from, /*parallel*/ true);
187 }
188
189 void seq_add_reference(OopOrNarrowOopStar from) {
190 add_reference_work(from, /*parallel*/ false);
191 }
192
193 void scrub(CardTableModRefBS* ctbs, BitMap* card_bm) {
194 HeapWord* hr_bot = hr()->bottom();
195 size_t hr_first_card_index = ctbs->index_for(hr_bot);
196 bm()->set_intersection_at_offset(*card_bm, hr_first_card_index);
197 #if PRT_COUNT_OCCUPIED
198 recount_occupied();
199 #endif
200 }
201
202 void add_card(CardIdx_t from_card_index) {
203 add_card_work(from_card_index, /*parallel*/ true);
204 }
205
206 void seq_add_card(CardIdx_t from_card_index) {
207 add_card_work(from_card_index, /*parallel*/ false);
208 }
209
210 // (Destructively) union the bitmap of the current table into the given
211 // bitmap (which is assumed to be of the same size.)
212 void union_bitmap_into(BitMap* bm) {
213 bm->set_union(_bm);
214 }
215
216 // Mem size in bytes.
217 size_t mem_size() const {
218 return sizeof(this) + _bm.size_in_words() * HeapWordSize;
219 }
220
221 static size_t fl_mem_size() {
222 PerRegionTable* cur = _free_list;
223 size_t res = 0;
224 while (cur != NULL) {
225 res += sizeof(PerRegionTable);
226 cur = cur->next_free();
227 }
228 return res;
229 }
230
231 // Requires "from" to be in "hr()".
232 bool contains_reference(OopOrNarrowOopStar from) const {
233 assert(hr()->is_in_reserved(from), "Precondition.");
234 size_t card_ind = pointer_delta(from, hr()->bottom(),
235 CardTableModRefBS::card_size);
236 return _bm.at(card_ind);
237 }
238 };
239
240 PerRegionTable* PerRegionTable::_free_list = NULL;
241
242
243 #define COUNT_PAR_EXPANDS 0
244
245 #if COUNT_PAR_EXPANDS
246 static jint n_par_expands = 0;
247 static jint n_par_contracts = 0;
248 static jint par_expand_list_len = 0;
249 static jint max_par_expand_list_len = 0;
250
251 static void print_par_expand() {
252 Atomic::inc(&n_par_expands);
253 Atomic::inc(&par_expand_list_len);
254 if (par_expand_list_len > max_par_expand_list_len) {
255 max_par_expand_list_len = par_expand_list_len;
256 }
257 if ((n_par_expands % 10) == 0) {
258 gclog_or_tty->print_cr("\n\n%d par expands: %d contracts, "
259 "len = %d, max_len = %d\n.",
260 n_par_expands, n_par_contracts, par_expand_list_len,
261 max_par_expand_list_len);
262 }
263 }
264 #endif
265
266 class PosParPRT: public PerRegionTable {
267 PerRegionTable** _par_tables;
268
269 enum SomePrivateConstants {
270 ReserveParTableExpansion = 1
271 };
272
273 void par_contract() {
274 assert(_par_tables != NULL, "Precondition.");
275 int n = HeapRegionRemSet::num_par_rem_sets()-1;
276 for (int i = 0; i < n; i++) {
277 _par_tables[i]->union_bitmap_into(bm());
278 PerRegionTable::free(_par_tables[i]);
279 _par_tables[i] = NULL;
280 }
281 #if PRT_COUNT_OCCUPIED
282 // We must recount the "occupied."
283 recount_occupied();
284 #endif
285 FREE_C_HEAP_ARRAY(PerRegionTable*, _par_tables);
286 _par_tables = NULL;
287 #if COUNT_PAR_EXPANDS
288 Atomic::inc(&n_par_contracts);
289 Atomic::dec(&par_expand_list_len);
290 #endif
291 }
292
293 static PerRegionTable** _par_table_fl;
294
295 PosParPRT* _next;
296
297 static PosParPRT* _free_list;
298
299 PerRegionTable** par_tables() const {
300 assert(uintptr_t(NULL) == 0, "Assumption.");
301 if (uintptr_t(_par_tables) <= ReserveParTableExpansion)
302 return NULL;
303 else
304 return _par_tables;
305 }
306
307 PosParPRT* _next_par_expanded;
308 PosParPRT* next_par_expanded() { return _next_par_expanded; }
309 void set_next_par_expanded(PosParPRT* ppprt) { _next_par_expanded = ppprt; }
310 static PosParPRT* _par_expanded_list;
311
312 public:
313
314 PosParPRT(HeapRegion* hr) : PerRegionTable(hr), _par_tables(NULL) {}
315
316 jint occupied() const {
317 jint res = PerRegionTable::occupied();
318 if (par_tables() != NULL) {
319 for (int i = 0; i < HeapRegionRemSet::num_par_rem_sets()-1; i++) {
320 res += par_tables()[i]->occupied();
321 }
322 }
323 return res;
324 }
325
326 void init(HeapRegion* hr) {
327 PerRegionTable::init(hr);
328 _next = NULL;
329 if (par_tables() != NULL) {
330 for (int i = 0; i < HeapRegionRemSet::num_par_rem_sets()-1; i++) {
331 par_tables()[i]->init(hr);
332 }
333 }
334 }
335
336 static void free(PosParPRT* prt) {
337 while (true) {
338 PosParPRT* fl = _free_list;
339 prt->set_next(fl);
340 PosParPRT* res =
341 (PosParPRT*)
342 Atomic::cmpxchg_ptr(prt, &_free_list, fl);
343 if (res == fl) return;
344 }
345 ShouldNotReachHere();
346 }
347
348 static PosParPRT* alloc(HeapRegion* hr) {
349 PosParPRT* fl = _free_list;
350 while (fl != NULL) {
351 PosParPRT* nxt = fl->next();
352 PosParPRT* res =
353 (PosParPRT*)
354 Atomic::cmpxchg_ptr(nxt, &_free_list, fl);
355 if (res == fl) {
356 fl->init(hr);
357 return fl;
358 } else {
359 fl = _free_list;
360 }
361 }
362 assert(fl == NULL, "Loop condition.");
363 return new PosParPRT(hr);
364 }
365
366 PosParPRT* next() const { return _next; }
367 void set_next(PosParPRT* nxt) { _next = nxt; }
368 PosParPRT** next_addr() { return &_next; }
369
370 bool should_expand(int tid) {
371 // Given that we now defer RSet updates for after a GC we don't
372 // really need to expand the tables any more. This code should be
373 // cleaned up in the future (see CR 6921087).
374 return false;
375 }
376
377 void par_expand() {
378 int n = HeapRegionRemSet::num_par_rem_sets()-1;
379 if (n <= 0) return;
380 if (_par_tables == NULL) {
381 PerRegionTable* res =
382 (PerRegionTable*)
383 Atomic::cmpxchg_ptr((PerRegionTable*)ReserveParTableExpansion,
384 &_par_tables, NULL);
385 if (res != NULL) return;
386 // Otherwise, we reserved the right to do the expansion.
387
388 PerRegionTable** ptables = NEW_C_HEAP_ARRAY(PerRegionTable*, n);
389 for (int i = 0; i < n; i++) {
390 PerRegionTable* ptable = PerRegionTable::alloc(hr());
391 ptables[i] = ptable;
392 }
393 // Here we do not need an atomic.
394 _par_tables = ptables;
395 #if COUNT_PAR_EXPANDS
396 print_par_expand();
397 #endif
398 // We must put this table on the expanded list.
399 PosParPRT* exp_head = _par_expanded_list;
400 while (true) {
401 set_next_par_expanded(exp_head);
402 PosParPRT* res =
403 (PosParPRT*)
404 Atomic::cmpxchg_ptr(this, &_par_expanded_list, exp_head);
405 if (res == exp_head) return;
406 // Otherwise.
407 exp_head = res;
408 }
409 ShouldNotReachHere();
410 }
411 }
412
413 void add_reference(OopOrNarrowOopStar from, int tid) {
414 // Expand if necessary.
415 PerRegionTable** pt = par_tables();
416 if (pt != NULL) {
417 // We always have to assume that mods to table 0 are in parallel,
418 // because of the claiming scheme in parallel expansion. A thread
419 // with tid != 0 that finds the table to be NULL, but doesn't succeed
420 // in claiming the right of expanding it, will end up in the else
421 // clause of the above if test. That thread could be delayed, and a
422 // thread 0 add reference could see the table expanded, and come
423 // here. Both threads would be adding in parallel. But we get to
424 // not use atomics for tids > 0.
425 if (tid == 0) {
426 PerRegionTable::add_reference(from);
427 } else {
428 pt[tid-1]->seq_add_reference(from);
429 }
430 } else {
431 // Not expanded -- add to the base table.
432 PerRegionTable::add_reference(from);
433 }
434 }
435
436 void scrub(CardTableModRefBS* ctbs, BitMap* card_bm) {
437 assert(_par_tables == NULL, "Precondition");
438 PerRegionTable::scrub(ctbs, card_bm);
439 }
440
441 size_t mem_size() const {
442 size_t res =
443 PerRegionTable::mem_size() + sizeof(this) - sizeof(PerRegionTable);
444 if (_par_tables != NULL) {
445 for (int i = 0; i < HeapRegionRemSet::num_par_rem_sets()-1; i++) {
446 res += _par_tables[i]->mem_size();
447 }
448 }
449 return res;
450 }
451
452 static size_t fl_mem_size() {
453 PosParPRT* cur = _free_list;
454 size_t res = 0;
455 while (cur != NULL) {
456 res += sizeof(PosParPRT);
457 cur = cur->next();
458 }
459 return res;
460 }
461
462 bool contains_reference(OopOrNarrowOopStar from) const {
463 if (PerRegionTable::contains_reference(from)) return true;
464 if (_par_tables != NULL) {
465 for (int i = 0; i < HeapRegionRemSet::num_par_rem_sets()-1; i++) {
466 if (_par_tables[i]->contains_reference(from)) return true;
467 }
468 }
469 return false;
470 }
471
472 static void par_contract_all();
473 };
474
475 void PosParPRT::par_contract_all() {
476 PosParPRT* hd = _par_expanded_list;
477 while (hd != NULL) {
478 PosParPRT* nxt = hd->next_par_expanded();
479 PosParPRT* res =
480 (PosParPRT*)
481 Atomic::cmpxchg_ptr(nxt, &_par_expanded_list, hd);
482 if (res == hd) {
483 // We claimed the right to contract this table.
484 hd->set_next_par_expanded(NULL);
485 hd->par_contract();
486 hd = _par_expanded_list;
487 } else {
488 hd = res;
489 }
490 }
491 }
492
493 PosParPRT* PosParPRT::_free_list = NULL;
494 PosParPRT* PosParPRT::_par_expanded_list = NULL;
495
496 jint OtherRegionsTable::_cache_probes = 0;
497 jint OtherRegionsTable::_cache_hits = 0;
498
499 size_t OtherRegionsTable::_max_fine_entries = 0;
500 size_t OtherRegionsTable::_mod_max_fine_entries_mask = 0;
501 #if SAMPLE_FOR_EVICTION
502 size_t OtherRegionsTable::_fine_eviction_stride = 0;
503 size_t OtherRegionsTable::_fine_eviction_sample_size = 0;
504 #endif
505
506 OtherRegionsTable::OtherRegionsTable(HeapRegion* hr) :
507 _g1h(G1CollectedHeap::heap()),
508 _m(Mutex::leaf, "An OtherRegionsTable lock", true),
509 _hr(hr),
510 _coarse_map(G1CollectedHeap::heap()->max_regions(),
511 false /* in-resource-area */),
512 _fine_grain_regions(NULL),
513 _n_fine_entries(0), _n_coarse_entries(0),
514 #if SAMPLE_FOR_EVICTION
515 _fine_eviction_start(0),
516 #endif
517 _sparse_table(hr)
518 {
519 typedef PosParPRT* PosParPRTPtr;
520 if (_max_fine_entries == 0) {
521 assert(_mod_max_fine_entries_mask == 0, "Both or none.");
522 size_t max_entries_log = (size_t)log2_long((jlong)G1RSetRegionEntries);
523 _max_fine_entries = (size_t)(1 << max_entries_log);
524 _mod_max_fine_entries_mask = _max_fine_entries - 1;
525 #if SAMPLE_FOR_EVICTION
526 assert(_fine_eviction_sample_size == 0
527 && _fine_eviction_stride == 0, "All init at same time.");
528 _fine_eviction_sample_size = MAX2((size_t)4, max_entries_log);
529 _fine_eviction_stride = _max_fine_entries / _fine_eviction_sample_size;
530 #endif
531 }
532 _fine_grain_regions = new PosParPRTPtr[_max_fine_entries];
533 if (_fine_grain_regions == NULL)
534 vm_exit_out_of_memory(sizeof(void*)*_max_fine_entries,
535 "Failed to allocate _fine_grain_entries.");
536 for (size_t i = 0; i < _max_fine_entries; i++) {
537 _fine_grain_regions[i] = NULL;
538 }
539 }
540
541 int** OtherRegionsTable::_from_card_cache = NULL;
542 size_t OtherRegionsTable::_from_card_cache_max_regions = 0;
543 size_t OtherRegionsTable::_from_card_cache_mem_size = 0;
544
545 void OtherRegionsTable::init_from_card_cache(size_t max_regions) {
546 _from_card_cache_max_regions = max_regions;
547
548 int n_par_rs = HeapRegionRemSet::num_par_rem_sets();
549 _from_card_cache = NEW_C_HEAP_ARRAY(int*, n_par_rs);
550 for (int i = 0; i < n_par_rs; i++) {
551 _from_card_cache[i] = NEW_C_HEAP_ARRAY(int, max_regions);
552 for (size_t j = 0; j < max_regions; j++) {
553 _from_card_cache[i][j] = -1; // An invalid value.
554 }
555 }
556 _from_card_cache_mem_size = n_par_rs * max_regions * sizeof(int);
557 }
558
559 void OtherRegionsTable::shrink_from_card_cache(size_t new_n_regs) {
560 for (int i = 0; i < HeapRegionRemSet::num_par_rem_sets(); i++) {
561 assert(new_n_regs <= _from_card_cache_max_regions, "Must be within max.");
562 for (size_t j = new_n_regs; j < _from_card_cache_max_regions; j++) {
563 _from_card_cache[i][j] = -1; // An invalid value.
564 }
565 }
566 }
567
568 #ifndef PRODUCT
569 void OtherRegionsTable::print_from_card_cache() {
570 for (int i = 0; i < HeapRegionRemSet::num_par_rem_sets(); i++) {
571 for (size_t j = 0; j < _from_card_cache_max_regions; j++) {
572 gclog_or_tty->print_cr("_from_card_cache[%d][%d] = %d.",
573 i, j, _from_card_cache[i][j]);
574 }
575 }
576 }
577 #endif
578
579 void OtherRegionsTable::add_reference(OopOrNarrowOopStar from, int tid) {
580 size_t cur_hrs_ind = hr()->hrs_index();
581
582 #if HRRS_VERBOSE
583 gclog_or_tty->print_cr("ORT::add_reference_work(" PTR_FORMAT "->" PTR_FORMAT ").",
584 from,
585 UseCompressedOops
586 ? oopDesc::load_decode_heap_oop((narrowOop*)from)
587 : oopDesc::load_decode_heap_oop((oop*)from));
588 #endif
589
590 int from_card = (int)(uintptr_t(from) >> CardTableModRefBS::card_shift);
591
592 #if HRRS_VERBOSE
593 gclog_or_tty->print_cr("Table for [" PTR_FORMAT "...): card %d (cache = %d)",
594 hr()->bottom(), from_card,
595 _from_card_cache[tid][cur_hrs_ind]);
596 #endif
597
598 #define COUNT_CACHE 0
599 #if COUNT_CACHE
600 jint p = Atomic::add(1, &_cache_probes);
601 if ((p % 10000) == 0) {
602 jint hits = _cache_hits;
603 gclog_or_tty->print_cr("%d/%d = %5.2f%% RS cache hits.",
604 _cache_hits, p, 100.0* (float)hits/(float)p);
605 }
606 #endif
607 if (from_card == _from_card_cache[tid][cur_hrs_ind]) {
608 #if HRRS_VERBOSE
609 gclog_or_tty->print_cr(" from-card cache hit.");
610 #endif
611 #if COUNT_CACHE
612 Atomic::inc(&_cache_hits);
613 #endif
614 assert(contains_reference(from), "We just added it!");
615 return;
616 } else {
617 _from_card_cache[tid][cur_hrs_ind] = from_card;
618 }
619
620 // Note that this may be a continued H region.
621 HeapRegion* from_hr = _g1h->heap_region_containing_raw(from);
622 RegionIdx_t from_hrs_ind = (RegionIdx_t) from_hr->hrs_index();
623
624 // If the region is already coarsened, return.
625 if (_coarse_map.at(from_hrs_ind)) {
626 #if HRRS_VERBOSE
627 gclog_or_tty->print_cr(" coarse map hit.");
628 #endif
629 assert(contains_reference(from), "We just added it!");
630 return;
631 }
632
633 // Otherwise find a per-region table to add it to.
634 size_t ind = from_hrs_ind & _mod_max_fine_entries_mask;
635 PosParPRT* prt = find_region_table(ind, from_hr);
636 if (prt == NULL) {
637 MutexLockerEx x(&_m, Mutex::_no_safepoint_check_flag);
638 // Confirm that it's really not there...
639 prt = find_region_table(ind, from_hr);
640 if (prt == NULL) {
641
642 uintptr_t from_hr_bot_card_index =
643 uintptr_t(from_hr->bottom())
644 >> CardTableModRefBS::card_shift;
645 CardIdx_t card_index = from_card - from_hr_bot_card_index;
646 assert(0 <= card_index && (size_t)card_index < HeapRegion::CardsPerRegion,
647 "Must be in range.");
648 if (G1HRRSUseSparseTable &&
649 _sparse_table.add_card(from_hrs_ind, card_index)) {
650 if (G1RecordHRRSOops) {
651 HeapRegionRemSet::record(hr(), from);
652 #if HRRS_VERBOSE
653 gclog_or_tty->print(" Added card " PTR_FORMAT " to region "
654 "[" PTR_FORMAT "...) for ref " PTR_FORMAT ".\n",
655 align_size_down(uintptr_t(from),
656 CardTableModRefBS::card_size),
657 hr()->bottom(), from);
658 #endif
659 }
660 #if HRRS_VERBOSE
661 gclog_or_tty->print_cr(" added card to sparse table.");
662 #endif
663 assert(contains_reference_locked(from), "We just added it!");
664 return;
665 } else {
666 #if HRRS_VERBOSE
667 gclog_or_tty->print_cr(" [tid %d] sparse table entry "
668 "overflow(f: %d, t: %d)",
669 tid, from_hrs_ind, cur_hrs_ind);
670 #endif
671 }
672
673 if (_n_fine_entries == _max_fine_entries) {
674 prt = delete_region_table();
675 } else {
676 prt = PosParPRT::alloc(from_hr);
677 }
678 prt->init(from_hr);
679
680 PosParPRT* first_prt = _fine_grain_regions[ind];
681 prt->set_next(first_prt); // XXX Maybe move to init?
682 _fine_grain_regions[ind] = prt;
683 _n_fine_entries++;
684
685 if (G1HRRSUseSparseTable) {
686 // Transfer from sparse to fine-grain.
687 SparsePRTEntry *sprt_entry = _sparse_table.get_entry(from_hrs_ind);
688 assert(sprt_entry != NULL, "There should have been an entry");
689 for (int i = 0; i < SparsePRTEntry::cards_num(); i++) {
690 CardIdx_t c = sprt_entry->card(i);
691 if (c != SparsePRTEntry::NullEntry) {
692 prt->add_card(c);
693 }
694 }
695 // Now we can delete the sparse entry.
696 bool res = _sparse_table.delete_entry(from_hrs_ind);
697 assert(res, "It should have been there.");
698 }
699 }
700 assert(prt != NULL && prt->hr() == from_hr, "consequence");
701 }
702 // Note that we can't assert "prt->hr() == from_hr", because of the
703 // possibility of concurrent reuse. But see head comment of
704 // OtherRegionsTable for why this is OK.
705 assert(prt != NULL, "Inv");
706
707 if (prt->should_expand(tid)) {
708 MutexLockerEx x(&_m, Mutex::_no_safepoint_check_flag);
709 HeapRegion* prt_hr = prt->hr();
710 if (prt_hr == from_hr) {
711 // Make sure the table still corresponds to the same region
712 prt->par_expand();
713 prt->add_reference(from, tid);
714 }
715 // else: The table has been concurrently coarsened, evicted, and
716 // the table data structure re-used for another table. So, we
717 // don't need to add the reference any more given that the table
718 // has been coarsened and the whole region will be scanned anyway.
719 } else {
720 prt->add_reference(from, tid);
721 }
722 if (G1RecordHRRSOops) {
723 HeapRegionRemSet::record(hr(), from);
724 #if HRRS_VERBOSE
725 gclog_or_tty->print("Added card " PTR_FORMAT " to region "
726 "[" PTR_FORMAT "...) for ref " PTR_FORMAT ".\n",
727 align_size_down(uintptr_t(from),
728 CardTableModRefBS::card_size),
729 hr()->bottom(), from);
730 #endif
731 }
732 assert(contains_reference(from), "We just added it!");
733 }
734
735 PosParPRT*
736 OtherRegionsTable::find_region_table(size_t ind, HeapRegion* hr) const {
737 assert(0 <= ind && ind < _max_fine_entries, "Preconditions.");
738 PosParPRT* prt = _fine_grain_regions[ind];
739 while (prt != NULL && prt->hr() != hr) {
740 prt = prt->next();
741 }
742 // Loop postcondition is the method postcondition.
743 return prt;
744 }
745
746
747 #define DRT_CENSUS 0
748
749 #if DRT_CENSUS
750 static const int HistoSize = 6;
751 static int global_histo[HistoSize] = { 0, 0, 0, 0, 0, 0 };
752 static int coarsenings = 0;
753 static int occ_sum = 0;
754 #endif
755
756 jint OtherRegionsTable::_n_coarsenings = 0;
757
758 PosParPRT* OtherRegionsTable::delete_region_table() {
759 #if DRT_CENSUS
760 int histo[HistoSize] = { 0, 0, 0, 0, 0, 0 };
761 const int histo_limits[] = { 1, 4, 16, 64, 256, 2048 };
762 #endif
763
764 assert(_m.owned_by_self(), "Precondition");
765 assert(_n_fine_entries == _max_fine_entries, "Precondition");
766 PosParPRT* max = NULL;
767 jint max_occ = 0;
768 PosParPRT** max_prev;
769 size_t max_ind;
770
771 #if SAMPLE_FOR_EVICTION
772 size_t i = _fine_eviction_start;
773 for (size_t k = 0; k < _fine_eviction_sample_size; k++) {
774 size_t ii = i;
775 // Make sure we get a non-NULL sample.
776 while (_fine_grain_regions[ii] == NULL) {
777 ii++;
778 if (ii == _max_fine_entries) ii = 0;
779 guarantee(ii != i, "We must find one.");
780 }
781 PosParPRT** prev = &_fine_grain_regions[ii];
782 PosParPRT* cur = *prev;
783 while (cur != NULL) {
784 jint cur_occ = cur->occupied();
785 if (max == NULL || cur_occ > max_occ) {
786 max = cur;
787 max_prev = prev;
788 max_ind = i;
789 max_occ = cur_occ;
790 }
791 prev = cur->next_addr();
792 cur = cur->next();
793 }
794 i = i + _fine_eviction_stride;
795 if (i >= _n_fine_entries) i = i - _n_fine_entries;
796 }
797 _fine_eviction_start++;
798 if (_fine_eviction_start >= _n_fine_entries)
799 _fine_eviction_start -= _n_fine_entries;
800 #else
801 for (int i = 0; i < _max_fine_entries; i++) {
802 PosParPRT** prev = &_fine_grain_regions[i];
803 PosParPRT* cur = *prev;
804 while (cur != NULL) {
805 jint cur_occ = cur->occupied();
806 #if DRT_CENSUS
807 for (int k = 0; k < HistoSize; k++) {
808 if (cur_occ <= histo_limits[k]) {
809 histo[k]++; global_histo[k]++; break;
810 }
811 }
812 #endif
813 if (max == NULL || cur_occ > max_occ) {
814 max = cur;
815 max_prev = prev;
816 max_ind = i;
817 max_occ = cur_occ;
818 }
819 prev = cur->next_addr();
820 cur = cur->next();
821 }
822 }
823 #endif
824 // XXX
825 guarantee(max != NULL, "Since _n_fine_entries > 0");
826 #if DRT_CENSUS
827 gclog_or_tty->print_cr("In a coarsening: histo of occs:");
828 for (int k = 0; k < HistoSize; k++) {
829 gclog_or_tty->print_cr(" <= %4d: %5d.", histo_limits[k], histo[k]);
830 }
831 coarsenings++;
832 occ_sum += max_occ;
833 if ((coarsenings % 100) == 0) {
834 gclog_or_tty->print_cr("\ncoarsenings = %d; global summary:", coarsenings);
835 for (int k = 0; k < HistoSize; k++) {
836 gclog_or_tty->print_cr(" <= %4d: %5d.", histo_limits[k], global_histo[k]);
837 }
838 gclog_or_tty->print_cr("Avg occ of deleted region = %6.2f.",
839 (float)occ_sum/(float)coarsenings);
840 }
841 #endif
842
843 // Set the corresponding coarse bit.
844 size_t max_hrs_index = max->hr()->hrs_index();
845 if (!_coarse_map.at(max_hrs_index)) {
846 _coarse_map.at_put(max_hrs_index, true);
847 _n_coarse_entries++;
848 #if 0
849 gclog_or_tty->print("Coarsened entry in region [" PTR_FORMAT "...] "
850 "for region [" PTR_FORMAT "...] (%d coarse entries).\n",
851 hr()->bottom(),
852 max->hr()->bottom(),
853 _n_coarse_entries);
854 #endif
855 }
856
857 // Unsplice.
858 *max_prev = max->next();
859 Atomic::inc(&_n_coarsenings);
860 _n_fine_entries--;
861 return max;
862 }
863
864
865 // At present, this must be called stop-world single-threaded.
866 void OtherRegionsTable::scrub(CardTableModRefBS* ctbs,
867 BitMap* region_bm, BitMap* card_bm) {
868 // First eliminated garbage regions from the coarse map.
869 if (G1RSScrubVerbose)
870 gclog_or_tty->print_cr("Scrubbing region "SIZE_FORMAT":",
871 hr()->hrs_index());
872
873 assert(_coarse_map.size() == region_bm->size(), "Precondition");
874 if (G1RSScrubVerbose)
875 gclog_or_tty->print(" Coarse map: before = %d...", _n_coarse_entries);
876 _coarse_map.set_intersection(*region_bm);
877 _n_coarse_entries = _coarse_map.count_one_bits();
878 if (G1RSScrubVerbose)
879 gclog_or_tty->print_cr(" after = %d.", _n_coarse_entries);
880
881 // Now do the fine-grained maps.
882 for (size_t i = 0; i < _max_fine_entries; i++) {
883 PosParPRT* cur = _fine_grain_regions[i];
884 PosParPRT** prev = &_fine_grain_regions[i];
885 while (cur != NULL) {
886 PosParPRT* nxt = cur->next();
887 // If the entire region is dead, eliminate.
888 if (G1RSScrubVerbose)
889 gclog_or_tty->print_cr(" For other region "SIZE_FORMAT":",
890 cur->hr()->hrs_index());
891 if (!region_bm->at(cur->hr()->hrs_index())) {
892 *prev = nxt;
893 cur->set_next(NULL);
894 _n_fine_entries--;
895 if (G1RSScrubVerbose)
896 gclog_or_tty->print_cr(" deleted via region map.");
897 PosParPRT::free(cur);
898 } else {
899 // Do fine-grain elimination.
900 if (G1RSScrubVerbose)
901 gclog_or_tty->print(" occ: before = %4d.", cur->occupied());
902 cur->scrub(ctbs, card_bm);
903 if (G1RSScrubVerbose)
904 gclog_or_tty->print_cr(" after = %4d.", cur->occupied());
905 // Did that empty the table completely?
906 if (cur->occupied() == 0) {
907 *prev = nxt;
908 cur->set_next(NULL);
909 _n_fine_entries--;
910 PosParPRT::free(cur);
911 } else {
912 prev = cur->next_addr();
913 }
914 }
915 cur = nxt;
916 }
917 }
918 // Since we may have deleted a from_card_cache entry from the RS, clear
919 // the FCC.
920 clear_fcc();
921 }
922
923
924 size_t OtherRegionsTable::occupied() const {
925 // Cast away const in this case.
926 MutexLockerEx x((Mutex*)&_m, Mutex::_no_safepoint_check_flag);
927 size_t sum = occ_fine();
928 sum += occ_sparse();
929 sum += occ_coarse();
930 return sum;
931 }
932
933 size_t OtherRegionsTable::occ_fine() const {
934 size_t sum = 0;
935 for (size_t i = 0; i < _max_fine_entries; i++) {
936 PosParPRT* cur = _fine_grain_regions[i];
937 while (cur != NULL) {
938 sum += cur->occupied();
939 cur = cur->next();
940 }
941 }
942 return sum;
943 }
944
945 size_t OtherRegionsTable::occ_coarse() const {
946 return (_n_coarse_entries * HeapRegion::CardsPerRegion);
947 }
948
949 size_t OtherRegionsTable::occ_sparse() const {
950 return _sparse_table.occupied();
951 }
952
953 size_t OtherRegionsTable::mem_size() const {
954 // Cast away const in this case.
955 MutexLockerEx x((Mutex*)&_m, Mutex::_no_safepoint_check_flag);
956 size_t sum = 0;
957 for (size_t i = 0; i < _max_fine_entries; i++) {
958 PosParPRT* cur = _fine_grain_regions[i];
959 while (cur != NULL) {
960 sum += cur->mem_size();
961 cur = cur->next();
962 }
963 }
964 sum += (sizeof(PosParPRT*) * _max_fine_entries);
965 sum += (_coarse_map.size_in_words() * HeapWordSize);
966 sum += (_sparse_table.mem_size());
967 sum += sizeof(*this) - sizeof(_sparse_table); // Avoid double counting above.
968 return sum;
969 }
970
971 size_t OtherRegionsTable::static_mem_size() {
972 return _from_card_cache_mem_size;
973 }
974
975 size_t OtherRegionsTable::fl_mem_size() {
976 return PerRegionTable::fl_mem_size() + PosParPRT::fl_mem_size();
977 }
978
979 void OtherRegionsTable::clear_fcc() {
980 for (int i = 0; i < HeapRegionRemSet::num_par_rem_sets(); i++) {
981 _from_card_cache[i][hr()->hrs_index()] = -1;
982 }
983 }
984
985 void OtherRegionsTable::clear() {
986 MutexLockerEx x(&_m, Mutex::_no_safepoint_check_flag);
987 for (size_t i = 0; i < _max_fine_entries; i++) {
988 PosParPRT* cur = _fine_grain_regions[i];
989 while (cur != NULL) {
990 PosParPRT* nxt = cur->next();
991 PosParPRT::free(cur);
992 cur = nxt;
993 }
994 _fine_grain_regions[i] = NULL;
995 }
996 _sparse_table.clear();
997 _coarse_map.clear();
998 _n_fine_entries = 0;
999 _n_coarse_entries = 0;
1000
1001 clear_fcc();
1002 }
1003
1004 void OtherRegionsTable::clear_incoming_entry(HeapRegion* from_hr) {
1005 MutexLockerEx x(&_m, Mutex::_no_safepoint_check_flag);
1006 size_t hrs_ind = from_hr->hrs_index();
1007 size_t ind = hrs_ind & _mod_max_fine_entries_mask;
1008 if (del_single_region_table(ind, from_hr)) {
1009 assert(!_coarse_map.at(hrs_ind), "Inv");
1010 } else {
1011 _coarse_map.par_at_put(hrs_ind, 0);
1012 }
1013 // Check to see if any of the fcc entries come from here.
1014 size_t hr_ind = hr()->hrs_index();
1015 for (int tid = 0; tid < HeapRegionRemSet::num_par_rem_sets(); tid++) {
1016 int fcc_ent = _from_card_cache[tid][hr_ind];
1017 if (fcc_ent != -1) {
1018 HeapWord* card_addr = (HeapWord*)
1019 (uintptr_t(fcc_ent) << CardTableModRefBS::card_shift);
1020 if (hr()->is_in_reserved(card_addr)) {
1021 // Clear the from card cache.
1022 _from_card_cache[tid][hr_ind] = -1;
1023 }
1024 }
1025 }
1026 }
1027
1028 bool OtherRegionsTable::del_single_region_table(size_t ind,
1029 HeapRegion* hr) {
1030 assert(0 <= ind && ind < _max_fine_entries, "Preconditions.");
1031 PosParPRT** prev_addr = &_fine_grain_regions[ind];
1032 PosParPRT* prt = *prev_addr;
1033 while (prt != NULL && prt->hr() != hr) {
1034 prev_addr = prt->next_addr();
1035 prt = prt->next();
1036 }
1037 if (prt != NULL) {
1038 assert(prt->hr() == hr, "Loop postcondition.");
1039 *prev_addr = prt->next();
1040 PosParPRT::free(prt);
1041 _n_fine_entries--;
1042 return true;
1043 } else {
1044 return false;
1045 }
1046 }
1047
1048 bool OtherRegionsTable::contains_reference(OopOrNarrowOopStar from) const {
1049 // Cast away const in this case.
1050 MutexLockerEx x((Mutex*)&_m, Mutex::_no_safepoint_check_flag);
1051 return contains_reference_locked(from);
1052 }
1053
1054 bool OtherRegionsTable::contains_reference_locked(OopOrNarrowOopStar from) const {
1055 HeapRegion* hr = _g1h->heap_region_containing_raw(from);
1056 if (hr == NULL) return false;
1057 RegionIdx_t hr_ind = (RegionIdx_t) hr->hrs_index();
1058 // Is this region in the coarse map?
1059 if (_coarse_map.at(hr_ind)) return true;
1060
1061 PosParPRT* prt = find_region_table(hr_ind & _mod_max_fine_entries_mask,
1062 hr);
1063 if (prt != NULL) {
1064 return prt->contains_reference(from);
1065
1066 } else {
1067 uintptr_t from_card =
1068 (uintptr_t(from) >> CardTableModRefBS::card_shift);
1069 uintptr_t hr_bot_card_index =
1070 uintptr_t(hr->bottom()) >> CardTableModRefBS::card_shift;
1071 assert(from_card >= hr_bot_card_index, "Inv");
1072 CardIdx_t card_index = from_card - hr_bot_card_index;
1073 assert(0 <= card_index && (size_t)card_index < HeapRegion::CardsPerRegion,
1074 "Must be in range.");
1075 return _sparse_table.contains_card(hr_ind, card_index);
1076 }
1077
1078
1079 }
1080
1081 void
1082 OtherRegionsTable::do_cleanup_work(HRRSCleanupTask* hrrs_cleanup_task) {
1083 _sparse_table.do_cleanup_work(hrrs_cleanup_task);
1084 }
1085
1086 // Determines how many threads can add records to an rset in parallel.
1087 // This can be done by either mutator threads together with the
1088 // concurrent refinement threads or GC threads.
1089 int HeapRegionRemSet::num_par_rem_sets() {
1090 return (int)MAX2(DirtyCardQueueSet::num_par_ids() + ConcurrentG1Refine::thread_num(), ParallelGCThreads);
1091 }
1092
1093 HeapRegionRemSet::HeapRegionRemSet(G1BlockOffsetSharedArray* bosa,
1094 HeapRegion* hr)
1095 : _bosa(bosa), _other_regions(hr) {
1096 reset_for_par_iteration();
1097 }
1098
1099 void HeapRegionRemSet::setup_remset_size() {
1100 // Setup sparse and fine-grain tables sizes.
1101 // table_size = base * (log(region_size / 1M) + 1)
1102 int region_size_log_mb = MAX2((int)HeapRegion::LogOfHRGrainBytes - (int)LOG_M, 0);
1103 if (FLAG_IS_DEFAULT(G1RSetSparseRegionEntries)) {
1104 G1RSetSparseRegionEntries = G1RSetSparseRegionEntriesBase * (region_size_log_mb + 1);
1105 }
1106 if (FLAG_IS_DEFAULT(G1RSetRegionEntries)) {
1107 G1RSetRegionEntries = G1RSetRegionEntriesBase * (region_size_log_mb + 1);
1108 }
1109 guarantee(G1RSetSparseRegionEntries > 0 && G1RSetRegionEntries > 0 , "Sanity");
1110 }
1111
1112 bool HeapRegionRemSet::claim_iter() {
1113 if (_iter_state != Unclaimed) return false;
1114 jint res = Atomic::cmpxchg(Claimed, (jint*)(&_iter_state), Unclaimed);
1115 return (res == Unclaimed);
1116 }
1117
1118 void HeapRegionRemSet::set_iter_complete() {
1119 _iter_state = Complete;
1120 }
1121
1122 bool HeapRegionRemSet::iter_is_complete() {
1123 return _iter_state == Complete;
1124 }
1125
1126 void HeapRegionRemSet::init_iterator(HeapRegionRemSetIterator* iter) const {
1127 iter->initialize(this);
1128 }
1129
1130 #ifndef PRODUCT
1131 void HeapRegionRemSet::print() const {
1132 HeapRegionRemSetIterator iter;
1133 init_iterator(&iter);
1134 size_t card_index;
1135 while (iter.has_next(card_index)) {
1136 HeapWord* card_start =
1137 G1CollectedHeap::heap()->bot_shared()->address_for_index(card_index);
1138 gclog_or_tty->print_cr(" Card " PTR_FORMAT, card_start);
1139 }
1140 // XXX
1141 if (iter.n_yielded() != occupied()) {
1142 gclog_or_tty->print_cr("Yielded disagrees with occupied:");
1143 gclog_or_tty->print_cr(" %6d yielded (%6d coarse, %6d fine).",
1144 iter.n_yielded(),
1145 iter.n_yielded_coarse(), iter.n_yielded_fine());
1146 gclog_or_tty->print_cr(" %6d occ (%6d coarse, %6d fine).",
1147 occupied(), occ_coarse(), occ_fine());
1148 }
1149 guarantee(iter.n_yielded() == occupied(),
1150 "We should have yielded all the represented cards.");
1151 }
1152 #endif
1153
1154 void HeapRegionRemSet::cleanup() {
1155 SparsePRT::cleanup_all();
1156 }
1157
1158 void HeapRegionRemSet::par_cleanup() {
1159 PosParPRT::par_contract_all();
1160 }
1161
1162 void HeapRegionRemSet::clear() {
1163 _other_regions.clear();
1164 assert(occupied() == 0, "Should be clear.");
1165 reset_for_par_iteration();
1166 }
1167
1168 void HeapRegionRemSet::reset_for_par_iteration() {
1169 _iter_state = Unclaimed;
1170 _iter_claimed = 0;
1171 // It's good to check this to make sure that the two methods are in sync.
1172 assert(verify_ready_for_par_iteration(), "post-condition");
1173 }
1174
1175 void HeapRegionRemSet::scrub(CardTableModRefBS* ctbs,
1176 BitMap* region_bm, BitMap* card_bm) {
1177 _other_regions.scrub(ctbs, region_bm, card_bm);
1178 }
1179
1180 //-------------------- Iteration --------------------
1181
1182 HeapRegionRemSetIterator::
1183 HeapRegionRemSetIterator() :
1184 _hrrs(NULL),
1185 _g1h(G1CollectedHeap::heap()),
1186 _bosa(NULL),
1187 _sparse_iter() { }
1188
1189 void HeapRegionRemSetIterator::initialize(const HeapRegionRemSet* hrrs) {
1190 _hrrs = hrrs;
1191 _coarse_map = &_hrrs->_other_regions._coarse_map;
1192 _fine_grain_regions = _hrrs->_other_regions._fine_grain_regions;
1193 _bosa = _hrrs->bosa();
1194
1195 _is = Sparse;
1196 // Set these values so that we increment to the first region.
1197 _coarse_cur_region_index = -1;
1198 _coarse_cur_region_cur_card = (HeapRegion::CardsPerRegion-1);
1199
1200 _cur_region_cur_card = 0;
1201
1202 _fine_array_index = -1;
1203 _fine_cur_prt = NULL;
1204
1205 _n_yielded_coarse = 0;
1206 _n_yielded_fine = 0;
1207 _n_yielded_sparse = 0;
1208
1209 _sparse_iter.init(&hrrs->_other_regions._sparse_table);
1210 }
1211
1212 bool HeapRegionRemSetIterator::coarse_has_next(size_t& card_index) {
1213 if (_hrrs->_other_regions._n_coarse_entries == 0) return false;
1214 // Go to the next card.
1215 _coarse_cur_region_cur_card++;
1216 // Was the last the last card in the current region?
1217 if (_coarse_cur_region_cur_card == HeapRegion::CardsPerRegion) {
1218 // Yes: find the next region. This may leave _coarse_cur_region_index
1219 // Set to the last index, in which case there are no more coarse
1220 // regions.
1221 _coarse_cur_region_index =
1222 (int) _coarse_map->get_next_one_offset(_coarse_cur_region_index + 1);
1223 if ((size_t)_coarse_cur_region_index < _coarse_map->size()) {
1224 _coarse_cur_region_cur_card = 0;
1225 HeapWord* r_bot =
1226 _g1h->region_at(_coarse_cur_region_index)->bottom();
1227 _cur_region_card_offset = _bosa->index_for(r_bot);
1228 } else {
1229 return false;
1230 }
1231 }
1232 // If we didn't return false above, then we can yield a card.
1233 card_index = _cur_region_card_offset + _coarse_cur_region_cur_card;
1234 return true;
1235 }
1236
1237 void HeapRegionRemSetIterator::fine_find_next_non_null_prt() {
1238 // Otherwise, find the next bucket list in the array.
1239 _fine_array_index++;
1240 while (_fine_array_index < (int) OtherRegionsTable::_max_fine_entries) {
1241 _fine_cur_prt = _fine_grain_regions[_fine_array_index];
1242 if (_fine_cur_prt != NULL) return;
1243 else _fine_array_index++;
1244 }
1245 assert(_fine_cur_prt == NULL, "Loop post");
1246 }
1247
1248 bool HeapRegionRemSetIterator::fine_has_next(size_t& card_index) {
1249 if (fine_has_next()) {
1250 _cur_region_cur_card =
1251 _fine_cur_prt->_bm.get_next_one_offset(_cur_region_cur_card + 1);
1252 }
1253 while (!fine_has_next()) {
1254 if (_cur_region_cur_card == (size_t) HeapRegion::CardsPerRegion) {
1255 _cur_region_cur_card = 0;
1256 _fine_cur_prt = _fine_cur_prt->next();
1257 }
1258 if (_fine_cur_prt == NULL) {
1259 fine_find_next_non_null_prt();
1260 if (_fine_cur_prt == NULL) return false;
1261 }
1262 assert(_fine_cur_prt != NULL && _cur_region_cur_card == 0,
1263 "inv.");
1264 HeapWord* r_bot =
1265 _fine_cur_prt->hr()->bottom();
1266 _cur_region_card_offset = _bosa->index_for(r_bot);
1267 _cur_region_cur_card = _fine_cur_prt->_bm.get_next_one_offset(0);
1268 }
1269 assert(fine_has_next(), "Or else we exited the loop via the return.");
1270 card_index = _cur_region_card_offset + _cur_region_cur_card;
1271 return true;
1272 }
1273
1274 bool HeapRegionRemSetIterator::fine_has_next() {
1275 return
1276 _fine_cur_prt != NULL &&
1277 _cur_region_cur_card < HeapRegion::CardsPerRegion;
1278 }
1279
1280 bool HeapRegionRemSetIterator::has_next(size_t& card_index) {
1281 switch (_is) {
1282 case Sparse:
1283 if (_sparse_iter.has_next(card_index)) {
1284 _n_yielded_sparse++;
1285 return true;
1286 }
1287 // Otherwise, deliberate fall-through
1288 _is = Fine;
1289 case Fine:
1290 if (fine_has_next(card_index)) {
1291 _n_yielded_fine++;
1292 return true;
1293 }
1294 // Otherwise, deliberate fall-through
1295 _is = Coarse;
1296 case Coarse:
1297 if (coarse_has_next(card_index)) {
1298 _n_yielded_coarse++;
1299 return true;
1300 }
1301 // Otherwise...
1302 break;
1303 }
1304 assert(ParallelGCThreads > 1 ||
1305 n_yielded() == _hrrs->occupied(),
1306 "Should have yielded all the cards in the rem set "
1307 "(in the non-par case).");
1308 return false;
1309 }
1310
1311
1312
1313 OopOrNarrowOopStar* HeapRegionRemSet::_recorded_oops = NULL;
1314 HeapWord** HeapRegionRemSet::_recorded_cards = NULL;
1315 HeapRegion** HeapRegionRemSet::_recorded_regions = NULL;
1316 int HeapRegionRemSet::_n_recorded = 0;
1317
1318 HeapRegionRemSet::Event* HeapRegionRemSet::_recorded_events = NULL;
1319 int* HeapRegionRemSet::_recorded_event_index = NULL;
1320 int HeapRegionRemSet::_n_recorded_events = 0;
1321
1322 void HeapRegionRemSet::record(HeapRegion* hr, OopOrNarrowOopStar f) {
1323 if (_recorded_oops == NULL) {
1324 assert(_n_recorded == 0
1325 && _recorded_cards == NULL
1326 && _recorded_regions == NULL,
1327 "Inv");
1328 _recorded_oops = NEW_C_HEAP_ARRAY(OopOrNarrowOopStar, MaxRecorded);
1329 _recorded_cards = NEW_C_HEAP_ARRAY(HeapWord*, MaxRecorded);
1330 _recorded_regions = NEW_C_HEAP_ARRAY(HeapRegion*, MaxRecorded);
1331 }
1332 if (_n_recorded == MaxRecorded) {
1333 gclog_or_tty->print_cr("Filled up 'recorded' (%d).", MaxRecorded);
1334 } else {
1335 _recorded_cards[_n_recorded] =
1336 (HeapWord*)align_size_down(uintptr_t(f),
1337 CardTableModRefBS::card_size);
1338 _recorded_oops[_n_recorded] = f;
1339 _recorded_regions[_n_recorded] = hr;
1340 _n_recorded++;
1341 }
1342 }
1343
1344 void HeapRegionRemSet::record_event(Event evnt) {
1345 if (!G1RecordHRRSEvents) return;
1346
1347 if (_recorded_events == NULL) {
1348 assert(_n_recorded_events == 0
1349 && _recorded_event_index == NULL,
1350 "Inv");
1351 _recorded_events = NEW_C_HEAP_ARRAY(Event, MaxRecordedEvents);
1352 _recorded_event_index = NEW_C_HEAP_ARRAY(int, MaxRecordedEvents);
1353 }
1354 if (_n_recorded_events == MaxRecordedEvents) {
1355 gclog_or_tty->print_cr("Filled up 'recorded_events' (%d).", MaxRecordedEvents);
1356 } else {
1357 _recorded_events[_n_recorded_events] = evnt;
1358 _recorded_event_index[_n_recorded_events] = _n_recorded;
1359 _n_recorded_events++;
1360 }
1361 }
1362
1363 void HeapRegionRemSet::print_event(outputStream* str, Event evnt) {
1364 switch (evnt) {
1365 case Event_EvacStart:
1366 str->print("Evac Start");
1367 break;
1368 case Event_EvacEnd:
1369 str->print("Evac End");
1370 break;
1371 case Event_RSUpdateEnd:
1372 str->print("RS Update End");
1373 break;
1374 }
1375 }
1376
1377 void HeapRegionRemSet::print_recorded() {
1378 int cur_evnt = 0;
1379 Event cur_evnt_kind;
1380 int cur_evnt_ind = 0;
1381 if (_n_recorded_events > 0) {
1382 cur_evnt_kind = _recorded_events[cur_evnt];
1383 cur_evnt_ind = _recorded_event_index[cur_evnt];
1384 }
1385
1386 for (int i = 0; i < _n_recorded; i++) {
1387 while (cur_evnt < _n_recorded_events && i == cur_evnt_ind) {
1388 gclog_or_tty->print("Event: ");
1389 print_event(gclog_or_tty, cur_evnt_kind);
1390 gclog_or_tty->print_cr("");
1391 cur_evnt++;
1392 if (cur_evnt < MaxRecordedEvents) {
1393 cur_evnt_kind = _recorded_events[cur_evnt];
1394 cur_evnt_ind = _recorded_event_index[cur_evnt];
1395 }
1396 }
1397 gclog_or_tty->print("Added card " PTR_FORMAT " to region [" PTR_FORMAT "...]"
1398 " for ref " PTR_FORMAT ".\n",
1399 _recorded_cards[i], _recorded_regions[i]->bottom(),
1400 _recorded_oops[i]);
1401 }
1402 }
1403
1404 void HeapRegionRemSet::reset_for_cleanup_tasks() {
1405 SparsePRT::reset_for_cleanup_tasks();
1406 }
1407
1408 void HeapRegionRemSet::do_cleanup_work(HRRSCleanupTask* hrrs_cleanup_task) {
1409 _other_regions.do_cleanup_work(hrrs_cleanup_task);
1410 }
1411
1412 void
1413 HeapRegionRemSet::finish_cleanup_task(HRRSCleanupTask* hrrs_cleanup_task) {
1414 SparsePRT::finish_cleanup_task(hrrs_cleanup_task);
1415 }
1416
1417 #ifndef PRODUCT
1418 void HeapRegionRemSet::test() {
1419 os::sleep(Thread::current(), (jlong)5000, false);
1420 G1CollectedHeap* g1h = G1CollectedHeap::heap();
1421
1422 // Run with "-XX:G1LogRSetRegionEntries=2", so that 1 and 5 end up in same
1423 // hash bucket.
1424 HeapRegion* hr0 = g1h->region_at(0);
1425 HeapRegion* hr1 = g1h->region_at(1);
1426 HeapRegion* hr2 = g1h->region_at(5);
1427 HeapRegion* hr3 = g1h->region_at(6);
1428 HeapRegion* hr4 = g1h->region_at(7);
1429 HeapRegion* hr5 = g1h->region_at(8);
1430
1431 HeapWord* hr1_start = hr1->bottom();
1432 HeapWord* hr1_mid = hr1_start + HeapRegion::GrainWords/2;
1433 HeapWord* hr1_last = hr1->end() - 1;
1434
1435 HeapWord* hr2_start = hr2->bottom();
1436 HeapWord* hr2_mid = hr2_start + HeapRegion::GrainWords/2;
1437 HeapWord* hr2_last = hr2->end() - 1;
1438
1439 HeapWord* hr3_start = hr3->bottom();
1440 HeapWord* hr3_mid = hr3_start + HeapRegion::GrainWords/2;
1441 HeapWord* hr3_last = hr3->end() - 1;
1442
1443 HeapRegionRemSet* hrrs = hr0->rem_set();
1444
1445 // Make three references from region 0x101...
1446 hrrs->add_reference((OopOrNarrowOopStar)hr1_start);
1447 hrrs->add_reference((OopOrNarrowOopStar)hr1_mid);
1448 hrrs->add_reference((OopOrNarrowOopStar)hr1_last);
1449
1450 hrrs->add_reference((OopOrNarrowOopStar)hr2_start);
1451 hrrs->add_reference((OopOrNarrowOopStar)hr2_mid);
1452 hrrs->add_reference((OopOrNarrowOopStar)hr2_last);
1453
1454 hrrs->add_reference((OopOrNarrowOopStar)hr3_start);
1455 hrrs->add_reference((OopOrNarrowOopStar)hr3_mid);
1456 hrrs->add_reference((OopOrNarrowOopStar)hr3_last);
1457
1458 // Now cause a coarsening.
1459 hrrs->add_reference((OopOrNarrowOopStar)hr4->bottom());
1460 hrrs->add_reference((OopOrNarrowOopStar)hr5->bottom());
1461
1462 // Now, does iteration yield these three?
1463 HeapRegionRemSetIterator iter;
1464 hrrs->init_iterator(&iter);
1465 size_t sum = 0;
1466 size_t card_index;
1467 while (iter.has_next(card_index)) {
1468 HeapWord* card_start =
1469 G1CollectedHeap::heap()->bot_shared()->address_for_index(card_index);
1470 gclog_or_tty->print_cr(" Card " PTR_FORMAT ".", card_start);
1471 sum++;
1472 }
1473 guarantee(sum == 11 - 3 + 2048, "Failure");
1474 guarantee(sum == hrrs->occupied(), "Failure");
1475 }
1476 #endif