1 /*
2 * Copyright (c) 2001, 2014, 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/padded.inline.hpp"
33 #include "memory/space.inline.hpp"
34 #include "oops/oop.inline.hpp"
35 #include "runtime/atomic.inline.hpp"
36 #include "utilities/bitMap.inline.hpp"
37 #include "utilities/globalDefinitions.hpp"
38 #include "utilities/growableArray.hpp"
39
40 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
41
42 class PerRegionTable: public CHeapObj<mtGC> {
43 friend class OtherRegionsTable;
44 friend class HeapRegionRemSetIterator;
45
46 HeapRegion* _hr;
47 BitMap _bm;
48 jint _occupied;
49
50 // next pointer for free/allocated 'all' list
51 PerRegionTable* _next;
52
53 // prev pointer for the allocated 'all' list
54 PerRegionTable* _prev;
55
56 // next pointer in collision list
57 PerRegionTable * _collision_list_next;
58
59 // Global free list of PRTs
60 static PerRegionTable* _free_list;
61
62 protected:
63 // We need access in order to union things into the base table.
64 BitMap* bm() { return &_bm; }
65
66 void recount_occupied() {
67 _occupied = (jint) bm()->count_one_bits();
68 }
69
70 PerRegionTable(HeapRegion* hr) :
71 _hr(hr),
72 _occupied(0),
73 _bm(HeapRegion::CardsPerRegion, false /* in-resource-area */),
74 _collision_list_next(NULL), _next(NULL), _prev(NULL)
75 {}
76
77 void add_card_work(CardIdx_t from_card, bool par) {
78 if (!_bm.at(from_card)) {
79 if (par) {
80 if (_bm.par_at_put(from_card, 1)) {
81 Atomic::inc(&_occupied);
82 }
83 } else {
84 _bm.at_put(from_card, 1);
85 _occupied++;
86 }
87 }
88 }
89
90 void add_reference_work(OopOrNarrowOopStar from, bool par) {
91 // Must make this robust in case "from" is not in "_hr", because of
92 // concurrency.
93
94 if (G1TraceHeapRegionRememberedSet) {
95 gclog_or_tty->print_cr(" PRT::Add_reference_work(" PTR_FORMAT "->" PTR_FORMAT").",
96 from,
97 UseCompressedOops
98 ? (void *)oopDesc::load_decode_heap_oop((narrowOop*)from)
99 : (void *)oopDesc::load_decode_heap_oop((oop*)from));
100 }
101
102 HeapRegion* loc_hr = hr();
103 // If the test below fails, then this table was reused concurrently
104 // with this operation. This is OK, since the old table was coarsened,
105 // and adding a bit to the new table is never incorrect.
106 // If the table used to belong to a continues humongous region and is
107 // now reused for the corresponding start humongous region, we need to
108 // make sure that we detect this. Thus, we call is_in_reserved_raw()
109 // instead of just is_in_reserved() here.
110 if (loc_hr->is_in_reserved_raw(from)) {
111 size_t hw_offset = pointer_delta((HeapWord*)from, loc_hr->bottom());
112 CardIdx_t from_card = (CardIdx_t)
113 hw_offset >> (CardTableModRefBS::card_shift - LogHeapWordSize);
114
115 assert(0 <= from_card && (size_t)from_card < HeapRegion::CardsPerRegion,
116 "Must be in range.");
117 add_card_work(from_card, par);
118 }
119 }
120
121 public:
122
123 HeapRegion* hr() const { return _hr; }
124
125 jint occupied() const {
126 // Overkill, but if we ever need it...
127 // guarantee(_occupied == _bm.count_one_bits(), "Check");
128 return _occupied;
129 }
130
131 void init(HeapRegion* hr, bool clear_links_to_all_list) {
132 if (clear_links_to_all_list) {
133 set_next(NULL);
134 set_prev(NULL);
135 }
136 _hr = hr;
137 _collision_list_next = NULL;
138 _occupied = 0;
139 _bm.clear();
140 }
141
142 void add_reference(OopOrNarrowOopStar from) {
143 add_reference_work(from, /*parallel*/ true);
144 }
145
146 void seq_add_reference(OopOrNarrowOopStar from) {
147 add_reference_work(from, /*parallel*/ false);
148 }
149
150 void scrub(CardTableModRefBS* ctbs, BitMap* card_bm) {
151 HeapWord* hr_bot = hr()->bottom();
152 size_t hr_first_card_index = ctbs->index_for(hr_bot);
153 bm()->set_intersection_at_offset(*card_bm, hr_first_card_index);
154 recount_occupied();
155 }
156
157 void add_card(CardIdx_t from_card_index) {
158 add_card_work(from_card_index, /*parallel*/ true);
159 }
160
161 void seq_add_card(CardIdx_t from_card_index) {
162 add_card_work(from_card_index, /*parallel*/ false);
163 }
164
165 // (Destructively) union the bitmap of the current table into the given
166 // bitmap (which is assumed to be of the same size.)
167 void union_bitmap_into(BitMap* bm) {
168 bm->set_union(_bm);
169 }
170
171 // Mem size in bytes.
172 size_t mem_size() const {
173 return sizeof(PerRegionTable) + _bm.size_in_words() * HeapWordSize;
174 }
175
176 // Requires "from" to be in "hr()".
177 bool contains_reference(OopOrNarrowOopStar from) const {
178 assert(hr()->is_in_reserved(from), "Precondition.");
179 size_t card_ind = pointer_delta(from, hr()->bottom(),
180 CardTableModRefBS::card_size);
181 return _bm.at(card_ind);
182 }
183
184 // Bulk-free the PRTs from prt to last, assumes that they are
185 // linked together using their _next field.
186 static void bulk_free(PerRegionTable* prt, PerRegionTable* last) {
187 while (true) {
188 PerRegionTable* fl = _free_list;
189 last->set_next(fl);
190 PerRegionTable* res = (PerRegionTable*) Atomic::cmpxchg_ptr(prt, &_free_list, fl);
191 if (res == fl) {
192 return;
193 }
194 }
195 ShouldNotReachHere();
196 }
197
198 static void free(PerRegionTable* prt) {
199 bulk_free(prt, prt);
200 }
201
202 // Returns an initialized PerRegionTable instance.
203 static PerRegionTable* alloc(HeapRegion* hr) {
204 PerRegionTable* fl = _free_list;
205 while (fl != NULL) {
206 PerRegionTable* nxt = fl->next();
207 PerRegionTable* res =
208 (PerRegionTable*)
209 Atomic::cmpxchg_ptr(nxt, &_free_list, fl);
210 if (res == fl) {
211 fl->init(hr, true);
212 return fl;
213 } else {
214 fl = _free_list;
215 }
216 }
217 assert(fl == NULL, "Loop condition.");
218 return new PerRegionTable(hr);
219 }
220
221 PerRegionTable* next() const { return _next; }
222 void set_next(PerRegionTable* next) { _next = next; }
223 PerRegionTable* prev() const { return _prev; }
224 void set_prev(PerRegionTable* prev) { _prev = prev; }
225
226 // Accessor and Modification routines for the pointer for the
227 // singly linked collision list that links the PRTs within the
228 // OtherRegionsTable::_fine_grain_regions hash table.
229 //
230 // It might be useful to also make the collision list doubly linked
231 // to avoid iteration over the collisions list during scrubbing/deletion.
232 // OTOH there might not be many collisions.
233
234 PerRegionTable* collision_list_next() const {
235 return _collision_list_next;
236 }
237
238 void set_collision_list_next(PerRegionTable* next) {
239 _collision_list_next = next;
240 }
241
242 PerRegionTable** collision_list_next_addr() {
243 return &_collision_list_next;
244 }
245
246 static size_t fl_mem_size() {
247 PerRegionTable* cur = _free_list;
248 size_t res = 0;
249 while (cur != NULL) {
250 res += cur->mem_size();
251 cur = cur->next();
252 }
253 return res;
254 }
255
256 static void test_fl_mem_size();
257 };
258
259 PerRegionTable* PerRegionTable::_free_list = NULL;
260
261 size_t OtherRegionsTable::_max_fine_entries = 0;
262 size_t OtherRegionsTable::_mod_max_fine_entries_mask = 0;
263 size_t OtherRegionsTable::_fine_eviction_stride = 0;
264 size_t OtherRegionsTable::_fine_eviction_sample_size = 0;
265
266 OtherRegionsTable::OtherRegionsTable(HeapRegion* hr, Mutex* m) :
267 _g1h(G1CollectedHeap::heap()),
268 _hr(hr), _m(m),
269 _coarse_map(G1CollectedHeap::heap()->max_regions(),
270 false /* in-resource-area */),
271 _fine_grain_regions(NULL),
272 _first_all_fine_prts(NULL), _last_all_fine_prts(NULL),
273 _n_fine_entries(0), _n_coarse_entries(0),
274 _fine_eviction_start(0),
275 _sparse_table(hr)
276 {
277 typedef PerRegionTable* PerRegionTablePtr;
278
279 if (_max_fine_entries == 0) {
280 assert(_mod_max_fine_entries_mask == 0, "Both or none.");
281 size_t max_entries_log = (size_t)log2_long((jlong)G1RSetRegionEntries);
282 _max_fine_entries = (size_t)1 << max_entries_log;
283 _mod_max_fine_entries_mask = _max_fine_entries - 1;
284
285 assert(_fine_eviction_sample_size == 0
286 && _fine_eviction_stride == 0, "All init at same time.");
287 _fine_eviction_sample_size = MAX2((size_t)4, max_entries_log);
288 _fine_eviction_stride = _max_fine_entries / _fine_eviction_sample_size;
289 }
290
291 _fine_grain_regions = NEW_C_HEAP_ARRAY3(PerRegionTablePtr, _max_fine_entries,
292 mtGC, 0, AllocFailStrategy::RETURN_NULL);
293
294 if (_fine_grain_regions == NULL) {
295 vm_exit_out_of_memory(sizeof(void*)*_max_fine_entries, OOM_MALLOC_ERROR,
296 "Failed to allocate _fine_grain_entries.");
297 }
298
299 for (size_t i = 0; i < _max_fine_entries; i++) {
300 _fine_grain_regions[i] = NULL;
301 }
302 }
303
304 void OtherRegionsTable::link_to_all(PerRegionTable* prt) {
305 // We always append to the beginning of the list for convenience;
306 // the order of entries in this list does not matter.
307 if (_first_all_fine_prts != NULL) {
308 assert(_first_all_fine_prts->prev() == NULL, "invariant");
309 _first_all_fine_prts->set_prev(prt);
310 prt->set_next(_first_all_fine_prts);
311 } else {
312 // this is the first element we insert. Adjust the "last" pointer
313 _last_all_fine_prts = prt;
314 assert(prt->next() == NULL, "just checking");
315 }
316 // the new element is always the first element without a predecessor
317 prt->set_prev(NULL);
318 _first_all_fine_prts = prt;
319
320 assert(prt->prev() == NULL, "just checking");
321 assert(_first_all_fine_prts == prt, "just checking");
322 assert((_first_all_fine_prts == NULL && _last_all_fine_prts == NULL) ||
323 (_first_all_fine_prts != NULL && _last_all_fine_prts != NULL),
324 "just checking");
325 assert(_last_all_fine_prts == NULL || _last_all_fine_prts->next() == NULL,
326 "just checking");
327 assert(_first_all_fine_prts == NULL || _first_all_fine_prts->prev() == NULL,
328 "just checking");
329 }
330
331 void OtherRegionsTable::unlink_from_all(PerRegionTable* prt) {
332 if (prt->prev() != NULL) {
333 assert(_first_all_fine_prts != prt, "just checking");
334 prt->prev()->set_next(prt->next());
335 // removing the last element in the list?
336 if (_last_all_fine_prts == prt) {
337 _last_all_fine_prts = prt->prev();
338 }
339 } else {
340 assert(_first_all_fine_prts == prt, "just checking");
341 _first_all_fine_prts = prt->next();
342 // list is empty now?
343 if (_first_all_fine_prts == NULL) {
344 _last_all_fine_prts = NULL;
345 }
346 }
347
348 if (prt->next() != NULL) {
349 prt->next()->set_prev(prt->prev());
350 }
351
352 prt->set_next(NULL);
353 prt->set_prev(NULL);
354
355 assert((_first_all_fine_prts == NULL && _last_all_fine_prts == NULL) ||
356 (_first_all_fine_prts != NULL && _last_all_fine_prts != NULL),
357 "just checking");
358 assert(_last_all_fine_prts == NULL || _last_all_fine_prts->next() == NULL,
359 "just checking");
360 assert(_first_all_fine_prts == NULL || _first_all_fine_prts->prev() == NULL,
361 "just checking");
362 }
363
364 int** FromCardCache::_cache = NULL;
365 uint FromCardCache::_max_regions = 0;
366 size_t FromCardCache::_static_mem_size = 0;
367
368 void FromCardCache::initialize(uint n_par_rs, uint max_num_regions) {
369 guarantee(_cache == NULL, "Should not call this multiple times");
370
371 _max_regions = max_num_regions;
372 _cache = Padded2DArray<int, mtGC>::create_unfreeable(n_par_rs,
373 _max_regions,
374 &_static_mem_size);
375
376 for (uint i = 0; i < n_par_rs; i++) {
377 for (uint j = 0; j < _max_regions; j++) {
378 set(i, j, InvalidCard);
379 }
380 }
381 }
382
383 void FromCardCache::shrink(uint new_num_regions) {
384 for (uint i = 0; i < HeapRegionRemSet::num_par_rem_sets(); i++) {
385 assert(new_num_regions <= _max_regions, "Must be within max.");
386 for (uint j = new_num_regions; j < _max_regions; j++) {
387 set(i, j, InvalidCard);
388 }
389 }
390 }
391
392 #ifndef PRODUCT
393 void FromCardCache::print(outputStream* out) {
394 for (uint i = 0; i < HeapRegionRemSet::num_par_rem_sets(); i++) {
395 for (uint j = 0; j < _max_regions; j++) {
396 out->print_cr("_from_card_cache[%u][%u] = %d.",
397 i, j, at(i, j));
398 }
399 }
400 }
401 #endif
402
403 void FromCardCache::clear(uint region_idx) {
404 uint num_par_remsets = HeapRegionRemSet::num_par_rem_sets();
405 for (uint i = 0; i < num_par_remsets; i++) {
406 set(i, region_idx, InvalidCard);
407 }
408 }
409
410 void OtherRegionsTable::init_from_card_cache(uint max_regions) {
411 FromCardCache::initialize(HeapRegionRemSet::num_par_rem_sets(), max_regions);
412 }
413
414 void OtherRegionsTable::shrink_from_card_cache(uint new_num_regions) {
415 FromCardCache::shrink(new_num_regions);
416 }
417
418 void OtherRegionsTable::print_from_card_cache() {
419 FromCardCache::print();
420 }
421
422 void OtherRegionsTable::add_reference(OopOrNarrowOopStar from, int tid) {
423 uint cur_hrs_ind = hr()->hrs_index();
424
425 if (G1TraceHeapRegionRememberedSet) {
426 gclog_or_tty->print_cr("ORT::add_reference_work(" PTR_FORMAT "->" PTR_FORMAT ").",
427 from,
428 UseCompressedOops
429 ? (void *)oopDesc::load_decode_heap_oop((narrowOop*)from)
430 : (void *)oopDesc::load_decode_heap_oop((oop*)from));
431 }
432
433 int from_card = (int)(uintptr_t(from) >> CardTableModRefBS::card_shift);
434
435 if (G1TraceHeapRegionRememberedSet) {
436 gclog_or_tty->print_cr("Table for [" PTR_FORMAT "...): card %d (cache = %d)",
437 hr()->bottom(), from_card,
438 FromCardCache::at((uint)tid, cur_hrs_ind));
439 }
440
441 if (FromCardCache::contains_or_replace((uint)tid, cur_hrs_ind, from_card)) {
442 if (G1TraceHeapRegionRememberedSet) {
443 gclog_or_tty->print_cr(" from-card cache hit.");
444 }
445 assert(contains_reference(from), "We just added it!");
446 return;
447 }
448
449 // Note that this may be a continued H region.
450 HeapRegion* from_hr = _g1h->heap_region_containing_raw(from);
451 RegionIdx_t from_hrs_ind = (RegionIdx_t) from_hr->hrs_index();
452
453 // If the region is already coarsened, return.
454 if (_coarse_map.at(from_hrs_ind)) {
455 if (G1TraceHeapRegionRememberedSet) {
456 gclog_or_tty->print_cr(" coarse map hit.");
457 }
458 assert(contains_reference(from), "We just added it!");
459 return;
460 }
461
462 // Otherwise find a per-region table to add it to.
463 size_t ind = from_hrs_ind & _mod_max_fine_entries_mask;
464 PerRegionTable* prt = find_region_table(ind, from_hr);
465 if (prt == NULL) {
466 MutexLockerEx x(_m, Mutex::_no_safepoint_check_flag);
467 // Confirm that it's really not there...
468 prt = find_region_table(ind, from_hr);
469 if (prt == NULL) {
470
471 uintptr_t from_hr_bot_card_index =
472 uintptr_t(from_hr->bottom())
473 >> CardTableModRefBS::card_shift;
474 CardIdx_t card_index = from_card - from_hr_bot_card_index;
475 assert(0 <= card_index && (size_t)card_index < HeapRegion::CardsPerRegion,
476 "Must be in range.");
477 if (G1HRRSUseSparseTable &&
478 _sparse_table.add_card(from_hrs_ind, card_index)) {
479 if (G1RecordHRRSOops) {
480 HeapRegionRemSet::record(hr(), from);
481 if (G1TraceHeapRegionRememberedSet) {
482 gclog_or_tty->print(" Added card " PTR_FORMAT " to region "
483 "[" PTR_FORMAT "...) for ref " PTR_FORMAT ".\n",
484 align_size_down(uintptr_t(from),
485 CardTableModRefBS::card_size),
486 hr()->bottom(), from);
487 }
488 }
489 if (G1TraceHeapRegionRememberedSet) {
490 gclog_or_tty->print_cr(" added card to sparse table.");
491 }
492 assert(contains_reference_locked(from), "We just added it!");
493 return;
494 } else {
495 if (G1TraceHeapRegionRememberedSet) {
496 gclog_or_tty->print_cr(" [tid %d] sparse table entry "
497 "overflow(f: %d, t: %u)",
498 tid, from_hrs_ind, cur_hrs_ind);
499 }
500 }
501
502 if (_n_fine_entries == _max_fine_entries) {
503 prt = delete_region_table();
504 // There is no need to clear the links to the 'all' list here:
505 // prt will be reused immediately, i.e. remain in the 'all' list.
506 prt->init(from_hr, false /* clear_links_to_all_list */);
507 } else {
508 prt = PerRegionTable::alloc(from_hr);
509 link_to_all(prt);
510 }
511
512 PerRegionTable* first_prt = _fine_grain_regions[ind];
513 prt->set_collision_list_next(first_prt);
514 _fine_grain_regions[ind] = prt;
515 _n_fine_entries++;
516
517 if (G1HRRSUseSparseTable) {
518 // Transfer from sparse to fine-grain.
519 SparsePRTEntry *sprt_entry = _sparse_table.get_entry(from_hrs_ind);
520 assert(sprt_entry != NULL, "There should have been an entry");
521 for (int i = 0; i < SparsePRTEntry::cards_num(); i++) {
522 CardIdx_t c = sprt_entry->card(i);
523 if (c != SparsePRTEntry::NullEntry) {
524 prt->add_card(c);
525 }
526 }
527 // Now we can delete the sparse entry.
528 bool res = _sparse_table.delete_entry(from_hrs_ind);
529 assert(res, "It should have been there.");
530 }
531 }
532 assert(prt != NULL && prt->hr() == from_hr, "consequence");
533 }
534 // Note that we can't assert "prt->hr() == from_hr", because of the
535 // possibility of concurrent reuse. But see head comment of
536 // OtherRegionsTable for why this is OK.
537 assert(prt != NULL, "Inv");
538
539 prt->add_reference(from);
540
541 if (G1RecordHRRSOops) {
542 HeapRegionRemSet::record(hr(), from);
543 if (G1TraceHeapRegionRememberedSet) {
544 gclog_or_tty->print("Added card " PTR_FORMAT " to region "
545 "[" PTR_FORMAT "...) for ref " PTR_FORMAT ".\n",
546 align_size_down(uintptr_t(from),
547 CardTableModRefBS::card_size),
548 hr()->bottom(), from);
549 }
550 }
551 assert(contains_reference(from), "We just added it!");
552 }
553
554 PerRegionTable*
555 OtherRegionsTable::find_region_table(size_t ind, HeapRegion* hr) const {
556 assert(0 <= ind && ind < _max_fine_entries, "Preconditions.");
557 PerRegionTable* prt = _fine_grain_regions[ind];
558 while (prt != NULL && prt->hr() != hr) {
559 prt = prt->collision_list_next();
560 }
561 // Loop postcondition is the method postcondition.
562 return prt;
563 }
564
565 jint OtherRegionsTable::_n_coarsenings = 0;
566
567 PerRegionTable* OtherRegionsTable::delete_region_table() {
568 assert(_m->owned_by_self(), "Precondition");
569 assert(_n_fine_entries == _max_fine_entries, "Precondition");
570 PerRegionTable* max = NULL;
571 jint max_occ = 0;
572 PerRegionTable** max_prev;
573 size_t max_ind;
574
575 size_t i = _fine_eviction_start;
576 for (size_t k = 0; k < _fine_eviction_sample_size; k++) {
577 size_t ii = i;
578 // Make sure we get a non-NULL sample.
579 while (_fine_grain_regions[ii] == NULL) {
580 ii++;
581 if (ii == _max_fine_entries) ii = 0;
582 guarantee(ii != i, "We must find one.");
583 }
584 PerRegionTable** prev = &_fine_grain_regions[ii];
585 PerRegionTable* cur = *prev;
586 while (cur != NULL) {
587 jint cur_occ = cur->occupied();
588 if (max == NULL || cur_occ > max_occ) {
589 max = cur;
590 max_prev = prev;
591 max_ind = i;
592 max_occ = cur_occ;
593 }
594 prev = cur->collision_list_next_addr();
595 cur = cur->collision_list_next();
596 }
597 i = i + _fine_eviction_stride;
598 if (i >= _n_fine_entries) i = i - _n_fine_entries;
599 }
600
601 _fine_eviction_start++;
602
603 if (_fine_eviction_start >= _n_fine_entries) {
604 _fine_eviction_start -= _n_fine_entries;
605 }
606
607 guarantee(max != NULL, "Since _n_fine_entries > 0");
608
609 // Set the corresponding coarse bit.
610 size_t max_hrs_index = (size_t) max->hr()->hrs_index();
611 if (!_coarse_map.at(max_hrs_index)) {
612 _coarse_map.at_put(max_hrs_index, true);
613 _n_coarse_entries++;
614 if (G1TraceHeapRegionRememberedSet) {
615 gclog_or_tty->print("Coarsened entry in region [" PTR_FORMAT "...] "
616 "for region [" PTR_FORMAT "...] (" SIZE_FORMAT " coarse entries).\n",
617 hr()->bottom(),
618 max->hr()->bottom(),
619 _n_coarse_entries);
620 }
621 }
622
623 // Unsplice.
624 *max_prev = max->collision_list_next();
625 Atomic::inc(&_n_coarsenings);
626 _n_fine_entries--;
627 return max;
628 }
629
630
631 // At present, this must be called stop-world single-threaded.
632 void OtherRegionsTable::scrub(CardTableModRefBS* ctbs,
633 BitMap* region_bm, BitMap* card_bm) {
634 // First eliminated garbage regions from the coarse map.
635 if (G1RSScrubVerbose) {
636 gclog_or_tty->print_cr("Scrubbing region %u:", hr()->hrs_index());
637 }
638
639 assert(_coarse_map.size() == region_bm->size(), "Precondition");
640 if (G1RSScrubVerbose) {
641 gclog_or_tty->print(" Coarse map: before = "SIZE_FORMAT"...",
642 _n_coarse_entries);
643 }
644 _coarse_map.set_intersection(*region_bm);
645 _n_coarse_entries = _coarse_map.count_one_bits();
646 if (G1RSScrubVerbose) {
647 gclog_or_tty->print_cr(" after = "SIZE_FORMAT".", _n_coarse_entries);
648 }
649
650 // Now do the fine-grained maps.
651 for (size_t i = 0; i < _max_fine_entries; i++) {
652 PerRegionTable* cur = _fine_grain_regions[i];
653 PerRegionTable** prev = &_fine_grain_regions[i];
654 while (cur != NULL) {
655 PerRegionTable* nxt = cur->collision_list_next();
656 // If the entire region is dead, eliminate.
657 if (G1RSScrubVerbose) {
658 gclog_or_tty->print_cr(" For other region %u:",
659 cur->hr()->hrs_index());
660 }
661 if (!region_bm->at((size_t) cur->hr()->hrs_index())) {
662 *prev = nxt;
663 cur->set_collision_list_next(NULL);
664 _n_fine_entries--;
665 if (G1RSScrubVerbose) {
666 gclog_or_tty->print_cr(" deleted via region map.");
667 }
668 unlink_from_all(cur);
669 PerRegionTable::free(cur);
670 } else {
671 // Do fine-grain elimination.
672 if (G1RSScrubVerbose) {
673 gclog_or_tty->print(" occ: before = %4d.", cur->occupied());
674 }
675 cur->scrub(ctbs, card_bm);
676 if (G1RSScrubVerbose) {
677 gclog_or_tty->print_cr(" after = %4d.", cur->occupied());
678 }
679 // Did that empty the table completely?
680 if (cur->occupied() == 0) {
681 *prev = nxt;
682 cur->set_collision_list_next(NULL);
683 _n_fine_entries--;
684 unlink_from_all(cur);
685 PerRegionTable::free(cur);
686 } else {
687 prev = cur->collision_list_next_addr();
688 }
689 }
690 cur = nxt;
691 }
692 }
693 // Since we may have deleted a from_card_cache entry from the RS, clear
694 // the FCC.
695 clear_fcc();
696 }
697
698
699 size_t OtherRegionsTable::occupied() const {
700 size_t sum = occ_fine();
701 sum += occ_sparse();
702 sum += occ_coarse();
703 return sum;
704 }
705
706 size_t OtherRegionsTable::occ_fine() const {
707 size_t sum = 0;
708
709 size_t num = 0;
710 PerRegionTable * cur = _first_all_fine_prts;
711 while (cur != NULL) {
712 sum += cur->occupied();
713 cur = cur->next();
714 num++;
715 }
716 guarantee(num == _n_fine_entries, "just checking");
717 return sum;
718 }
719
720 size_t OtherRegionsTable::occ_coarse() const {
721 return (_n_coarse_entries * HeapRegion::CardsPerRegion);
722 }
723
724 size_t OtherRegionsTable::occ_sparse() const {
725 return _sparse_table.occupied();
726 }
727
728 size_t OtherRegionsTable::mem_size() const {
729 size_t sum = 0;
730 // all PRTs are of the same size so it is sufficient to query only one of them.
731 if (_first_all_fine_prts != NULL) {
732 assert(_last_all_fine_prts != NULL &&
733 _first_all_fine_prts->mem_size() == _last_all_fine_prts->mem_size(), "check that mem_size() is constant");
734 sum += _first_all_fine_prts->mem_size() * _n_fine_entries;
735 }
736 sum += (sizeof(PerRegionTable*) * _max_fine_entries);
737 sum += (_coarse_map.size_in_words() * HeapWordSize);
738 sum += (_sparse_table.mem_size());
739 sum += sizeof(OtherRegionsTable) - sizeof(_sparse_table); // Avoid double counting above.
740 return sum;
741 }
742
743 size_t OtherRegionsTable::static_mem_size() {
744 return FromCardCache::static_mem_size();
745 }
746
747 size_t OtherRegionsTable::fl_mem_size() {
748 return PerRegionTable::fl_mem_size();
749 }
750
751 void OtherRegionsTable::clear_fcc() {
752 FromCardCache::clear(hr()->hrs_index());
753 }
754
755 void OtherRegionsTable::clear() {
756 // if there are no entries, skip this step
757 if (_first_all_fine_prts != NULL) {
758 guarantee(_first_all_fine_prts != NULL && _last_all_fine_prts != NULL, "just checking");
759 PerRegionTable::bulk_free(_first_all_fine_prts, _last_all_fine_prts);
760 memset(_fine_grain_regions, 0, _max_fine_entries * sizeof(_fine_grain_regions[0]));
761 } else {
762 guarantee(_first_all_fine_prts == NULL && _last_all_fine_prts == NULL, "just checking");
763 }
764
765 _first_all_fine_prts = _last_all_fine_prts = NULL;
766 _sparse_table.clear();
767 _coarse_map.clear();
768 _n_fine_entries = 0;
769 _n_coarse_entries = 0;
770
771 clear_fcc();
772 }
773
774 bool OtherRegionsTable::del_single_region_table(size_t ind,
775 HeapRegion* hr) {
776 assert(0 <= ind && ind < _max_fine_entries, "Preconditions.");
777 PerRegionTable** prev_addr = &_fine_grain_regions[ind];
778 PerRegionTable* prt = *prev_addr;
779 while (prt != NULL && prt->hr() != hr) {
780 prev_addr = prt->collision_list_next_addr();
781 prt = prt->collision_list_next();
782 }
783 if (prt != NULL) {
784 assert(prt->hr() == hr, "Loop postcondition.");
785 *prev_addr = prt->collision_list_next();
786 unlink_from_all(prt);
787 PerRegionTable::free(prt);
788 _n_fine_entries--;
789 return true;
790 } else {
791 return false;
792 }
793 }
794
795 bool OtherRegionsTable::contains_reference(OopOrNarrowOopStar from) const {
796 // Cast away const in this case.
797 MutexLockerEx x((Mutex*)_m, Mutex::_no_safepoint_check_flag);
798 return contains_reference_locked(from);
799 }
800
801 bool OtherRegionsTable::contains_reference_locked(OopOrNarrowOopStar from) const {
802 HeapRegion* hr = _g1h->heap_region_containing_raw(from);
803 RegionIdx_t hr_ind = (RegionIdx_t) hr->hrs_index();
804 // Is this region in the coarse map?
805 if (_coarse_map.at(hr_ind)) return true;
806
807 PerRegionTable* prt = find_region_table(hr_ind & _mod_max_fine_entries_mask,
808 hr);
809 if (prt != NULL) {
810 return prt->contains_reference(from);
811
812 } else {
813 uintptr_t from_card =
814 (uintptr_t(from) >> CardTableModRefBS::card_shift);
815 uintptr_t hr_bot_card_index =
816 uintptr_t(hr->bottom()) >> CardTableModRefBS::card_shift;
817 assert(from_card >= hr_bot_card_index, "Inv");
818 CardIdx_t card_index = from_card - hr_bot_card_index;
819 assert(0 <= card_index && (size_t)card_index < HeapRegion::CardsPerRegion,
820 "Must be in range.");
821 return _sparse_table.contains_card(hr_ind, card_index);
822 }
823 }
824
825 void
826 OtherRegionsTable::do_cleanup_work(HRRSCleanupTask* hrrs_cleanup_task) {
827 _sparse_table.do_cleanup_work(hrrs_cleanup_task);
828 }
829
830 // Determines how many threads can add records to an rset in parallel.
831 // This can be done by either mutator threads together with the
832 // concurrent refinement threads or GC threads.
833 uint HeapRegionRemSet::num_par_rem_sets() {
834 return MAX2(DirtyCardQueueSet::num_par_ids() + ConcurrentG1Refine::thread_num(), (uint)ParallelGCThreads);
835 }
836
837 HeapRegionRemSet::HeapRegionRemSet(G1BlockOffsetSharedArray* bosa,
838 HeapRegion* hr)
839 : _bosa(bosa),
840 _m(Mutex::leaf, FormatBuffer<128>("HeapRegionRemSet lock #%u", hr->hrs_index()), true),
841 _code_roots(), _other_regions(hr, &_m) {
842 reset_for_par_iteration();
843 }
844
845 void HeapRegionRemSet::setup_remset_size() {
846 // Setup sparse and fine-grain tables sizes.
847 // table_size = base * (log(region_size / 1M) + 1)
848 const int LOG_M = 20;
849 int region_size_log_mb = MAX2(HeapRegion::LogOfHRGrainBytes - LOG_M, 0);
850 if (FLAG_IS_DEFAULT(G1RSetSparseRegionEntries)) {
851 G1RSetSparseRegionEntries = G1RSetSparseRegionEntriesBase * (region_size_log_mb + 1);
852 }
853 if (FLAG_IS_DEFAULT(G1RSetRegionEntries)) {
854 G1RSetRegionEntries = G1RSetRegionEntriesBase * (region_size_log_mb + 1);
855 }
856 guarantee(G1RSetSparseRegionEntries > 0 && G1RSetRegionEntries > 0 , "Sanity");
857 }
858
859 bool HeapRegionRemSet::claim_iter() {
860 if (_iter_state != Unclaimed) return false;
861 jint res = Atomic::cmpxchg(Claimed, (jint*)(&_iter_state), Unclaimed);
862 return (res == Unclaimed);
863 }
864
865 void HeapRegionRemSet::set_iter_complete() {
866 _iter_state = Complete;
867 }
868
869 bool HeapRegionRemSet::iter_is_complete() {
870 return _iter_state == Complete;
871 }
872
873 #ifndef PRODUCT
874 void HeapRegionRemSet::print() {
875 HeapRegionRemSetIterator iter(this);
876 size_t card_index;
877 while (iter.has_next(card_index)) {
878 HeapWord* card_start =
879 G1CollectedHeap::heap()->bot_shared()->address_for_index(card_index);
880 gclog_or_tty->print_cr(" Card " PTR_FORMAT, card_start);
881 }
882 if (iter.n_yielded() != occupied()) {
883 gclog_or_tty->print_cr("Yielded disagrees with occupied:");
884 gclog_or_tty->print_cr(" " SIZE_FORMAT_W(6) " yielded (" SIZE_FORMAT_W(6)
885 " coarse, " SIZE_FORMAT_W(6) " fine).",
886 iter.n_yielded(),
887 iter.n_yielded_coarse(), iter.n_yielded_fine());
888 gclog_or_tty->print_cr(" " SIZE_FORMAT_W(6) " occ (" SIZE_FORMAT_W(6)
889 " coarse, " SIZE_FORMAT_W(6) " fine).",
890 occupied(), occ_coarse(), occ_fine());
891 }
892 guarantee(iter.n_yielded() == occupied(),
893 "We should have yielded all the represented cards.");
894 }
895 #endif
896
897 void HeapRegionRemSet::cleanup() {
898 SparsePRT::cleanup_all();
899 }
900
901 void HeapRegionRemSet::clear() {
902 MutexLockerEx x(&_m, Mutex::_no_safepoint_check_flag);
903 clear_locked();
904 }
905
906 void HeapRegionRemSet::clear_locked() {
907 _code_roots.clear();
908 _other_regions.clear();
909 assert(occupied_locked() == 0, "Should be clear.");
910 reset_for_par_iteration();
911 }
912
913 void HeapRegionRemSet::reset_for_par_iteration() {
914 _iter_state = Unclaimed;
915 _iter_claimed = 0;
916 // It's good to check this to make sure that the two methods are in sync.
917 assert(verify_ready_for_par_iteration(), "post-condition");
918 }
919
920 void HeapRegionRemSet::scrub(CardTableModRefBS* ctbs,
921 BitMap* region_bm, BitMap* card_bm) {
922 _other_regions.scrub(ctbs, region_bm, card_bm);
923 }
924
925 // Code roots support
926
927 void HeapRegionRemSet::add_strong_code_root(nmethod* nm) {
928 assert(nm != NULL, "sanity");
929 _code_roots.add(nm);
930 }
931
932 void HeapRegionRemSet::remove_strong_code_root(nmethod* nm) {
933 assert(nm != NULL, "sanity");
934 _code_roots.remove(nm);
935 // Check that there were no duplicates
936 guarantee(!_code_roots.contains(nm), "duplicate entry found");
937 }
938
939 class NMethodMigrationOopClosure : public OopClosure {
940 G1CollectedHeap* _g1h;
941 HeapRegion* _from;
942 nmethod* _nm;
943
944 uint _num_self_forwarded;
945
946 template <class T> void do_oop_work(T* p) {
947 T heap_oop = oopDesc::load_heap_oop(p);
948 if (!oopDesc::is_null(heap_oop)) {
949 oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
950 if (_from->is_in(obj)) {
951 // Reference still points into the source region.
952 // Since roots are immediately evacuated this means that
953 // we must have self forwarded the object
954 assert(obj->is_forwarded(),
955 err_msg("code roots should be immediately evacuated. "
956 "Ref: "PTR_FORMAT", "
957 "Obj: "PTR_FORMAT", "
958 "Region: "HR_FORMAT,
959 p, (void*) obj, HR_FORMAT_PARAMS(_from)));
960 assert(obj->forwardee() == obj,
961 err_msg("not self forwarded? obj = "PTR_FORMAT, (void*)obj));
962
963 // The object has been self forwarded.
964 // Note, if we're during an initial mark pause, there is
965 // no need to explicitly mark object. It will be marked
966 // during the regular evacuation failure handling code.
967 _num_self_forwarded++;
968 } else {
969 // The reference points into a promotion or to-space region
970 HeapRegion* to = _g1h->heap_region_containing(obj);
971 to->rem_set()->add_strong_code_root(_nm);
972 }
973 }
974 }
975
976 public:
977 NMethodMigrationOopClosure(G1CollectedHeap* g1h, HeapRegion* from, nmethod* nm):
978 _g1h(g1h), _from(from), _nm(nm), _num_self_forwarded(0) {}
979
980 void do_oop(narrowOop* p) { do_oop_work(p); }
981 void do_oop(oop* p) { do_oop_work(p); }
982
983 uint retain() { return _num_self_forwarded > 0; }
984 };
985
986 void HeapRegionRemSet::migrate_strong_code_roots() {
987 assert(hr()->in_collection_set(), "only collection set regions");
988 assert(!hr()->isHumongous(),
989 err_msg("humongous region "HR_FORMAT" should not have been added to the collection set",
990 HR_FORMAT_PARAMS(hr())));
991
992 ResourceMark rm;
993
994 // List of code blobs to retain for this region
995 GrowableArray<nmethod*> to_be_retained(10);
996 G1CollectedHeap* g1h = G1CollectedHeap::heap();
997
998 while (!_code_roots.is_empty()) {
999 nmethod *nm = _code_roots.pop();
1000 if (nm != NULL) {
1001 NMethodMigrationOopClosure oop_cl(g1h, hr(), nm);
1002 nm->oops_do(&oop_cl);
1003 if (oop_cl.retain()) {
1004 to_be_retained.push(nm);
1005 }
1006 }
1007 }
1008
1009 // Now push any code roots we need to retain
1010 assert(to_be_retained.is_empty() || hr()->evacuation_failed(),
1011 "Retained nmethod list must be empty or "
1012 "evacuation of this region failed");
1013
1014 while (to_be_retained.is_nonempty()) {
1015 nmethod* nm = to_be_retained.pop();
1016 assert(nm != NULL, "sanity");
1017 add_strong_code_root(nm);
1018 }
1019 }
1020
1021 void HeapRegionRemSet::strong_code_roots_do(CodeBlobClosure* blk) const {
1022 _code_roots.nmethods_do(blk);
1023 }
1024
1025 size_t HeapRegionRemSet::strong_code_roots_mem_size() {
1026 return _code_roots.mem_size();
1027 }
1028
1029 HeapRegionRemSetIterator:: HeapRegionRemSetIterator(HeapRegionRemSet* hrrs) :
1030 _hrrs(hrrs),
1031 _g1h(G1CollectedHeap::heap()),
1032 _coarse_map(&hrrs->_other_regions._coarse_map),
1033 _bosa(hrrs->bosa()),
1034 _is(Sparse),
1035 // Set these values so that we increment to the first region.
1036 _coarse_cur_region_index(-1),
1037 _coarse_cur_region_cur_card(HeapRegion::CardsPerRegion-1),
1038 _cur_card_in_prt(HeapRegion::CardsPerRegion),
1039 _fine_cur_prt(NULL),
1040 _n_yielded_coarse(0),
1041 _n_yielded_fine(0),
1042 _n_yielded_sparse(0),
1043 _sparse_iter(&hrrs->_other_regions._sparse_table) {}
1044
1045 bool HeapRegionRemSetIterator::coarse_has_next(size_t& card_index) {
1046 if (_hrrs->_other_regions._n_coarse_entries == 0) return false;
1047 // Go to the next card.
1048 _coarse_cur_region_cur_card++;
1049 // Was the last the last card in the current region?
1050 if (_coarse_cur_region_cur_card == HeapRegion::CardsPerRegion) {
1051 // Yes: find the next region. This may leave _coarse_cur_region_index
1052 // Set to the last index, in which case there are no more coarse
1053 // regions.
1054 _coarse_cur_region_index =
1055 (int) _coarse_map->get_next_one_offset(_coarse_cur_region_index + 1);
1056 if ((size_t)_coarse_cur_region_index < _coarse_map->size()) {
1057 _coarse_cur_region_cur_card = 0;
1058 HeapWord* r_bot =
1059 _g1h->region_at((uint) _coarse_cur_region_index)->bottom();
1060 _cur_region_card_offset = _bosa->index_for(r_bot);
1061 } else {
1062 return false;
1063 }
1064 }
1065 // If we didn't return false above, then we can yield a card.
1066 card_index = _cur_region_card_offset + _coarse_cur_region_cur_card;
1067 return true;
1068 }
1069
1070 bool HeapRegionRemSetIterator::fine_has_next(size_t& card_index) {
1071 if (fine_has_next()) {
1072 _cur_card_in_prt =
1073 _fine_cur_prt->_bm.get_next_one_offset(_cur_card_in_prt + 1);
1074 }
1075 if (_cur_card_in_prt == HeapRegion::CardsPerRegion) {
1076 // _fine_cur_prt may still be NULL in case if there are not PRTs at all for
1077 // the remembered set.
1078 if (_fine_cur_prt == NULL || _fine_cur_prt->next() == NULL) {
1079 return false;
1080 }
1081 PerRegionTable* next_prt = _fine_cur_prt->next();
1082 switch_to_prt(next_prt);
1083 _cur_card_in_prt = _fine_cur_prt->_bm.get_next_one_offset(_cur_card_in_prt + 1);
1084 }
1085
1086 card_index = _cur_region_card_offset + _cur_card_in_prt;
1087 guarantee(_cur_card_in_prt < HeapRegion::CardsPerRegion,
1088 err_msg("Card index "SIZE_FORMAT" must be within the region", _cur_card_in_prt));
1089 return true;
1090 }
1091
1092 bool HeapRegionRemSetIterator::fine_has_next() {
1093 return _cur_card_in_prt != HeapRegion::CardsPerRegion;
1094 }
1095
1096 void HeapRegionRemSetIterator::switch_to_prt(PerRegionTable* prt) {
1097 assert(prt != NULL, "Cannot switch to NULL prt");
1098 _fine_cur_prt = prt;
1099
1100 HeapWord* r_bot = _fine_cur_prt->hr()->bottom();
1101 _cur_region_card_offset = _bosa->index_for(r_bot);
1102
1103 // The bitmap scan for the PRT always scans from _cur_region_cur_card + 1.
1104 // To avoid special-casing this start case, and not miss the first bitmap
1105 // entry, initialize _cur_region_cur_card with -1 instead of 0.
1106 _cur_card_in_prt = (size_t)-1;
1107 }
1108
1109 bool HeapRegionRemSetIterator::has_next(size_t& card_index) {
1110 switch (_is) {
1111 case Sparse: {
1112 if (_sparse_iter.has_next(card_index)) {
1113 _n_yielded_sparse++;
1114 return true;
1115 }
1116 // Otherwise, deliberate fall-through
1117 _is = Fine;
1118 PerRegionTable* initial_fine_prt = _hrrs->_other_regions._first_all_fine_prts;
1119 if (initial_fine_prt != NULL) {
1120 switch_to_prt(_hrrs->_other_regions._first_all_fine_prts);
1121 }
1122 }
1123 case Fine:
1124 if (fine_has_next(card_index)) {
1125 _n_yielded_fine++;
1126 return true;
1127 }
1128 // Otherwise, deliberate fall-through
1129 _is = Coarse;
1130 case Coarse:
1131 if (coarse_has_next(card_index)) {
1132 _n_yielded_coarse++;
1133 return true;
1134 }
1135 // Otherwise...
1136 break;
1137 }
1138 assert(ParallelGCThreads > 1 ||
1139 n_yielded() == _hrrs->occupied(),
1140 "Should have yielded all the cards in the rem set "
1141 "(in the non-par case).");
1142 return false;
1143 }
1144
1145
1146
1147 OopOrNarrowOopStar* HeapRegionRemSet::_recorded_oops = NULL;
1148 HeapWord** HeapRegionRemSet::_recorded_cards = NULL;
1149 HeapRegion** HeapRegionRemSet::_recorded_regions = NULL;
1150 int HeapRegionRemSet::_n_recorded = 0;
1151
1152 HeapRegionRemSet::Event* HeapRegionRemSet::_recorded_events = NULL;
1153 int* HeapRegionRemSet::_recorded_event_index = NULL;
1154 int HeapRegionRemSet::_n_recorded_events = 0;
1155
1156 void HeapRegionRemSet::record(HeapRegion* hr, OopOrNarrowOopStar f) {
1157 if (_recorded_oops == NULL) {
1158 assert(_n_recorded == 0
1159 && _recorded_cards == NULL
1160 && _recorded_regions == NULL,
1161 "Inv");
1162 _recorded_oops = NEW_C_HEAP_ARRAY(OopOrNarrowOopStar, MaxRecorded, mtGC);
1163 _recorded_cards = NEW_C_HEAP_ARRAY(HeapWord*, MaxRecorded, mtGC);
1164 _recorded_regions = NEW_C_HEAP_ARRAY(HeapRegion*, MaxRecorded, mtGC);
1165 }
1166 if (_n_recorded == MaxRecorded) {
1167 gclog_or_tty->print_cr("Filled up 'recorded' (%d).", MaxRecorded);
1168 } else {
1169 _recorded_cards[_n_recorded] =
1170 (HeapWord*)align_size_down(uintptr_t(f),
1171 CardTableModRefBS::card_size);
1172 _recorded_oops[_n_recorded] = f;
1173 _recorded_regions[_n_recorded] = hr;
1174 _n_recorded++;
1175 }
1176 }
1177
1178 void HeapRegionRemSet::record_event(Event evnt) {
1179 if (!G1RecordHRRSEvents) return;
1180
1181 if (_recorded_events == NULL) {
1182 assert(_n_recorded_events == 0
1183 && _recorded_event_index == NULL,
1184 "Inv");
1185 _recorded_events = NEW_C_HEAP_ARRAY(Event, MaxRecordedEvents, mtGC);
1186 _recorded_event_index = NEW_C_HEAP_ARRAY(int, MaxRecordedEvents, mtGC);
1187 }
1188 if (_n_recorded_events == MaxRecordedEvents) {
1189 gclog_or_tty->print_cr("Filled up 'recorded_events' (%d).", MaxRecordedEvents);
1190 } else {
1191 _recorded_events[_n_recorded_events] = evnt;
1192 _recorded_event_index[_n_recorded_events] = _n_recorded;
1193 _n_recorded_events++;
1194 }
1195 }
1196
1197 void HeapRegionRemSet::print_event(outputStream* str, Event evnt) {
1198 switch (evnt) {
1199 case Event_EvacStart:
1200 str->print("Evac Start");
1201 break;
1202 case Event_EvacEnd:
1203 str->print("Evac End");
1204 break;
1205 case Event_RSUpdateEnd:
1206 str->print("RS Update End");
1207 break;
1208 }
1209 }
1210
1211 void HeapRegionRemSet::print_recorded() {
1212 int cur_evnt = 0;
1213 Event cur_evnt_kind;
1214 int cur_evnt_ind = 0;
1215 if (_n_recorded_events > 0) {
1216 cur_evnt_kind = _recorded_events[cur_evnt];
1217 cur_evnt_ind = _recorded_event_index[cur_evnt];
1218 }
1219
1220 for (int i = 0; i < _n_recorded; i++) {
1221 while (cur_evnt < _n_recorded_events && i == cur_evnt_ind) {
1222 gclog_or_tty->print("Event: ");
1223 print_event(gclog_or_tty, cur_evnt_kind);
1224 gclog_or_tty->cr();
1225 cur_evnt++;
1226 if (cur_evnt < MaxRecordedEvents) {
1227 cur_evnt_kind = _recorded_events[cur_evnt];
1228 cur_evnt_ind = _recorded_event_index[cur_evnt];
1229 }
1230 }
1231 gclog_or_tty->print("Added card " PTR_FORMAT " to region [" PTR_FORMAT "...]"
1232 " for ref " PTR_FORMAT ".\n",
1233 _recorded_cards[i], _recorded_regions[i]->bottom(),
1234 _recorded_oops[i]);
1235 }
1236 }
1237
1238 void HeapRegionRemSet::reset_for_cleanup_tasks() {
1239 SparsePRT::reset_for_cleanup_tasks();
1240 }
1241
1242 void HeapRegionRemSet::do_cleanup_work(HRRSCleanupTask* hrrs_cleanup_task) {
1243 _other_regions.do_cleanup_work(hrrs_cleanup_task);
1244 }
1245
1246 void
1247 HeapRegionRemSet::finish_cleanup_task(HRRSCleanupTask* hrrs_cleanup_task) {
1248 SparsePRT::finish_cleanup_task(hrrs_cleanup_task);
1249 }
1250
1251 #ifndef PRODUCT
1252 void PerRegionTable::test_fl_mem_size() {
1253 PerRegionTable* dummy = alloc(NULL);
1254
1255 size_t min_prt_size = sizeof(void*) + dummy->bm()->size_in_words() * HeapWordSize;
1256 assert(dummy->mem_size() > min_prt_size,
1257 err_msg("PerRegionTable memory usage is suspiciously small, only has "SIZE_FORMAT" bytes. "
1258 "Should be at least "SIZE_FORMAT" bytes.", dummy->mem_size(), min_prt_size));
1259 free(dummy);
1260 guarantee(dummy->mem_size() == fl_mem_size(), "fl_mem_size() does not return the correct element size");
1261 // try to reset the state
1262 _free_list = NULL;
1263 delete dummy;
1264 }
1265
1266 void HeapRegionRemSet::test_prt() {
1267 PerRegionTable::test_fl_mem_size();
1268 }
1269
1270 void HeapRegionRemSet::test() {
1271 os::sleep(Thread::current(), (jlong)5000, false);
1272 G1CollectedHeap* g1h = G1CollectedHeap::heap();
1273
1274 // Run with "-XX:G1LogRSetRegionEntries=2", so that 1 and 5 end up in same
1275 // hash bucket.
1276 HeapRegion* hr0 = g1h->region_at(0);
1277 HeapRegion* hr1 = g1h->region_at(1);
1278 HeapRegion* hr2 = g1h->region_at(5);
1279 HeapRegion* hr3 = g1h->region_at(6);
1280 HeapRegion* hr4 = g1h->region_at(7);
1281 HeapRegion* hr5 = g1h->region_at(8);
1282
1283 HeapWord* hr1_start = hr1->bottom();
1284 HeapWord* hr1_mid = hr1_start + HeapRegion::GrainWords/2;
1285 HeapWord* hr1_last = hr1->end() - 1;
1286
1287 HeapWord* hr2_start = hr2->bottom();
1288 HeapWord* hr2_mid = hr2_start + HeapRegion::GrainWords/2;
1289 HeapWord* hr2_last = hr2->end() - 1;
1290
1291 HeapWord* hr3_start = hr3->bottom();
1292 HeapWord* hr3_mid = hr3_start + HeapRegion::GrainWords/2;
1293 HeapWord* hr3_last = hr3->end() - 1;
1294
1295 HeapRegionRemSet* hrrs = hr0->rem_set();
1296
1297 // Make three references from region 0x101...
1298 hrrs->add_reference((OopOrNarrowOopStar)hr1_start);
1299 hrrs->add_reference((OopOrNarrowOopStar)hr1_mid);
1300 hrrs->add_reference((OopOrNarrowOopStar)hr1_last);
1301
1302 hrrs->add_reference((OopOrNarrowOopStar)hr2_start);
1303 hrrs->add_reference((OopOrNarrowOopStar)hr2_mid);
1304 hrrs->add_reference((OopOrNarrowOopStar)hr2_last);
1305
1306 hrrs->add_reference((OopOrNarrowOopStar)hr3_start);
1307 hrrs->add_reference((OopOrNarrowOopStar)hr3_mid);
1308 hrrs->add_reference((OopOrNarrowOopStar)hr3_last);
1309
1310 // Now cause a coarsening.
1311 hrrs->add_reference((OopOrNarrowOopStar)hr4->bottom());
1312 hrrs->add_reference((OopOrNarrowOopStar)hr5->bottom());
1313
1314 // Now, does iteration yield these three?
1315 HeapRegionRemSetIterator iter(hrrs);
1316 size_t sum = 0;
1317 size_t card_index;
1318 while (iter.has_next(card_index)) {
1319 HeapWord* card_start =
1320 G1CollectedHeap::heap()->bot_shared()->address_for_index(card_index);
1321 gclog_or_tty->print_cr(" Card " PTR_FORMAT ".", card_start);
1322 sum++;
1323 }
1324 guarantee(sum == 11 - 3 + 2048, "Failure");
1325 guarantee(sum == hrrs->occupied(), "Failure");
1326 }
1327 #endif