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/space.inline.hpp"
33 #include "oops/oop.inline.hpp"
34 #include "utilities/bitMap.inline.hpp"
35 #include "utilities/globalDefinitions.hpp"
36 #include "utilities/growableArray.hpp"
37
38 class PerRegionTable: public CHeapObj<mtGC> {
39 friend class OtherRegionsTable;
40 friend class HeapRegionRemSetIterator;
41
42 HeapRegion* _hr;
43 BitMap _bm;
44 jint _occupied;
45
46 // next pointer for free/allocated 'all' list
47 PerRegionTable* _next;
48
49 // prev pointer for the allocated 'all' list
50 PerRegionTable* _prev;
51
52 // next pointer in collision list
53 PerRegionTable * _collision_list_next;
54
55 // Global free list of PRTs
56 static PerRegionTable* _free_list;
57
58 protected:
59 // We need access in order to union things into the base table.
60 BitMap* bm() { return &_bm; }
61
62 void recount_occupied() {
63 _occupied = (jint) bm()->count_one_bits();
64 }
65
66 PerRegionTable(HeapRegion* hr) :
67 _hr(hr),
68 _occupied(0),
69 _bm(HeapRegion::CardsPerRegion, false /* in-resource-area */),
70 _collision_list_next(NULL), _next(NULL), _prev(NULL)
71 {}
72
73 void add_card_work(CardIdx_t from_card, bool par) {
74 if (!_bm.at(from_card)) {
75 if (par) {
76 if (_bm.par_at_put(from_card, 1)) {
77 Atomic::inc(&_occupied);
78 }
79 } else {
80 _bm.at_put(from_card, 1);
81 _occupied++;
82 }
83 }
84 }
85
86 void add_reference_work(OopOrNarrowOopStar from, bool par) {
87 // Must make this robust in case "from" is not in "_hr", because of
88 // concurrency.
89
90 if (G1TraceHeapRegionRememberedSet) {
91 gclog_or_tty->print_cr(" PRT::Add_reference_work(" PTR_FORMAT "->" PTR_FORMAT").",
92 from,
93 UseCompressedOops
94 ? (void *)oopDesc::load_decode_heap_oop((narrowOop*)from)
95 : (void *)oopDesc::load_decode_heap_oop((oop*)from));
96 }
97
98 HeapRegion* loc_hr = hr();
99 // If the test below fails, then this table was reused concurrently
100 // with this operation. This is OK, since the old table was coarsened,
101 // and adding a bit to the new table is never incorrect.
102 // If the table used to belong to a continues humongous region and is
103 // now reused for the corresponding start humongous region, we need to
104 // make sure that we detect this. Thus, we call is_in_reserved_raw()
105 // instead of just is_in_reserved() here.
106 if (loc_hr->is_in_reserved_raw(from)) {
107 size_t hw_offset = pointer_delta((HeapWord*)from, loc_hr->bottom());
108 CardIdx_t from_card = (CardIdx_t)
109 hw_offset >> (CardTableModRefBS::card_shift - LogHeapWordSize);
110
111 assert(0 <= from_card && (size_t)from_card < HeapRegion::CardsPerRegion,
112 "Must be in range.");
113 add_card_work(from_card, par);
114 }
115 }
116
117 public:
118
119 HeapRegion* hr() const { return _hr; }
120
121 jint occupied() const {
122 // Overkill, but if we ever need it...
123 // guarantee(_occupied == _bm.count_one_bits(), "Check");
124 return _occupied;
125 }
126
127 void init(HeapRegion* hr, bool clear_links_to_all_list) {
128 if (clear_links_to_all_list) {
129 set_next(NULL);
130 set_prev(NULL);
131 }
132 _hr = hr;
133 _collision_list_next = NULL;
134 _occupied = 0;
135 _bm.clear();
136 }
137
138 void add_reference(OopOrNarrowOopStar from) {
139 add_reference_work(from, /*parallel*/ true);
140 }
141
142 void seq_add_reference(OopOrNarrowOopStar from) {
143 add_reference_work(from, /*parallel*/ false);
144 }
145
146 void scrub(CardTableModRefBS* ctbs, BitMap* card_bm) {
147 HeapWord* hr_bot = hr()->bottom();
148 size_t hr_first_card_index = ctbs->index_for(hr_bot);
149 bm()->set_intersection_at_offset(*card_bm, hr_first_card_index);
150 recount_occupied();
151 }
152
153 void add_card(CardIdx_t from_card_index) {
154 add_card_work(from_card_index, /*parallel*/ true);
155 }
156
157 void seq_add_card(CardIdx_t from_card_index) {
158 add_card_work(from_card_index, /*parallel*/ false);
159 }
160
161 // (Destructively) union the bitmap of the current table into the given
162 // bitmap (which is assumed to be of the same size.)
163 void union_bitmap_into(BitMap* bm) {
164 bm->set_union(_bm);
165 }
166
167 // Mem size in bytes.
168 size_t mem_size() const {
169 return sizeof(this) + _bm.size_in_words() * HeapWordSize;
170 }
171
172 // Requires "from" to be in "hr()".
173 bool contains_reference(OopOrNarrowOopStar from) const {
174 assert(hr()->is_in_reserved(from), "Precondition.");
175 size_t card_ind = pointer_delta(from, hr()->bottom(),
176 CardTableModRefBS::card_size);
177 return _bm.at(card_ind);
178 }
179
180 // Bulk-free the PRTs from prt to last, assumes that they are
181 // linked together using their _next field.
182 static void bulk_free(PerRegionTable* prt, PerRegionTable* last) {
183 while (true) {
184 PerRegionTable* fl = _free_list;
185 last->set_next(fl);
186 PerRegionTable* res = (PerRegionTable*) Atomic::cmpxchg_ptr(prt, &_free_list, fl);
187 if (res == fl) {
188 return;
189 }
190 }
191 ShouldNotReachHere();
192 }
193
194 static void free(PerRegionTable* prt) {
195 bulk_free(prt, prt);
196 }
197
198 // Returns an initialized PerRegionTable instance.
199 static PerRegionTable* alloc(HeapRegion* hr) {
200 PerRegionTable* fl = _free_list;
201 while (fl != NULL) {
202 PerRegionTable* nxt = fl->next();
203 PerRegionTable* res =
204 (PerRegionTable*)
205 Atomic::cmpxchg_ptr(nxt, &_free_list, fl);
206 if (res == fl) {
207 fl->init(hr, true);
208 return fl;
209 } else {
210 fl = _free_list;
211 }
212 }
213 assert(fl == NULL, "Loop condition.");
214 return new PerRegionTable(hr);
215 }
216
217 PerRegionTable* next() const { return _next; }
218 void set_next(PerRegionTable* next) { _next = next; }
219 PerRegionTable* prev() const { return _prev; }
220 void set_prev(PerRegionTable* prev) { _prev = prev; }
221
222 // Accessor and Modification routines for the pointer for the
223 // singly linked collision list that links the PRTs within the
224 // OtherRegionsTable::_fine_grain_regions hash table.
225 //
226 // It might be useful to also make the collision list doubly linked
227 // to avoid iteration over the collisions list during scrubbing/deletion.
228 // OTOH there might not be many collisions.
229
230 PerRegionTable* collision_list_next() const {
231 return _collision_list_next;
232 }
233
234 void set_collision_list_next(PerRegionTable* next) {
235 _collision_list_next = next;
236 }
237
238 PerRegionTable** collision_list_next_addr() {
239 return &_collision_list_next;
240 }
241
242 static size_t fl_mem_size() {
243 PerRegionTable* cur = _free_list;
244 size_t res = 0;
245 while (cur != NULL) {
246 res += cur->mem_size();
247 cur = cur->next();
248 }
249 return res;
250 }
251
252 static void test_fl_mem_size();
253 };
254
255 PerRegionTable* PerRegionTable::_free_list = NULL;
256
257 size_t OtherRegionsTable::_max_fine_entries = 0;
258 size_t OtherRegionsTable::_mod_max_fine_entries_mask = 0;
259 size_t OtherRegionsTable::_fine_eviction_stride = 0;
260 size_t OtherRegionsTable::_fine_eviction_sample_size = 0;
261
262 OtherRegionsTable::OtherRegionsTable(HeapRegion* hr, Mutex* m) :
263 _g1h(G1CollectedHeap::heap()),
264 _hr(hr), _m(m),
265 _coarse_map(G1CollectedHeap::heap()->max_regions(),
266 false /* in-resource-area */),
267 _fine_grain_regions(NULL),
268 _first_all_fine_prts(NULL), _last_all_fine_prts(NULL),
269 _n_fine_entries(0), _n_coarse_entries(0),
270 _fine_eviction_start(0),
271 _sparse_table(hr)
272 {
273 typedef PerRegionTable* PerRegionTablePtr;
274
275 if (_max_fine_entries == 0) {
276 assert(_mod_max_fine_entries_mask == 0, "Both or none.");
277 size_t max_entries_log = (size_t)log2_long((jlong)G1RSetRegionEntries);
278 _max_fine_entries = (size_t)1 << max_entries_log;
279 _mod_max_fine_entries_mask = _max_fine_entries - 1;
280
281 assert(_fine_eviction_sample_size == 0
282 && _fine_eviction_stride == 0, "All init at same time.");
283 _fine_eviction_sample_size = MAX2((size_t)4, max_entries_log);
284 _fine_eviction_stride = _max_fine_entries / _fine_eviction_sample_size;
285 }
286
287 _fine_grain_regions = NEW_C_HEAP_ARRAY3(PerRegionTablePtr, _max_fine_entries,
288 mtGC, 0, AllocFailStrategy::RETURN_NULL);
289
290 if (_fine_grain_regions == NULL) {
291 vm_exit_out_of_memory(sizeof(void*)*_max_fine_entries, OOM_MALLOC_ERROR,
292 "Failed to allocate _fine_grain_entries.");
293 }
294
295 for (size_t i = 0; i < _max_fine_entries; i++) {
296 _fine_grain_regions[i] = NULL;
297 }
298 }
299
300 void OtherRegionsTable::link_to_all(PerRegionTable* prt) {
301 // We always append to the beginning of the list for convenience;
302 // the order of entries in this list does not matter.
303 if (_first_all_fine_prts != NULL) {
304 assert(_first_all_fine_prts->prev() == NULL, "invariant");
305 _first_all_fine_prts->set_prev(prt);
306 prt->set_next(_first_all_fine_prts);
307 } else {
308 // this is the first element we insert. Adjust the "last" pointer
309 _last_all_fine_prts = prt;
310 assert(prt->next() == NULL, "just checking");
311 }
312 // the new element is always the first element without a predecessor
313 prt->set_prev(NULL);
314 _first_all_fine_prts = prt;
315
316 assert(prt->prev() == NULL, "just checking");
317 assert(_first_all_fine_prts == prt, "just checking");
318 assert((_first_all_fine_prts == NULL && _last_all_fine_prts == NULL) ||
319 (_first_all_fine_prts != NULL && _last_all_fine_prts != NULL),
320 "just checking");
321 assert(_last_all_fine_prts == NULL || _last_all_fine_prts->next() == NULL,
322 "just checking");
323 assert(_first_all_fine_prts == NULL || _first_all_fine_prts->prev() == NULL,
324 "just checking");
325 }
326
327 void OtherRegionsTable::unlink_from_all(PerRegionTable* prt) {
328 if (prt->prev() != NULL) {
329 assert(_first_all_fine_prts != prt, "just checking");
330 prt->prev()->set_next(prt->next());
331 // removing the last element in the list?
332 if (_last_all_fine_prts == prt) {
333 _last_all_fine_prts = prt->prev();
334 }
335 } else {
336 assert(_first_all_fine_prts == prt, "just checking");
337 _first_all_fine_prts = prt->next();
338 // list is empty now?
339 if (_first_all_fine_prts == NULL) {
340 _last_all_fine_prts = NULL;
341 }
342 }
343
344 if (prt->next() != NULL) {
345 prt->next()->set_prev(prt->prev());
346 }
347
348 prt->set_next(NULL);
349 prt->set_prev(NULL);
350
351 assert((_first_all_fine_prts == NULL && _last_all_fine_prts == NULL) ||
352 (_first_all_fine_prts != NULL && _last_all_fine_prts != NULL),
353 "just checking");
354 assert(_last_all_fine_prts == NULL || _last_all_fine_prts->next() == NULL,
355 "just checking");
356 assert(_first_all_fine_prts == NULL || _first_all_fine_prts->prev() == NULL,
357 "just checking");
358 }
359
360 int** OtherRegionsTable::_from_card_cache = NULL;
361 size_t OtherRegionsTable::_from_card_cache_max_regions = 0;
362 size_t OtherRegionsTable::_from_card_cache_mem_size = 0;
363
364 void OtherRegionsTable::init_from_card_cache(size_t max_regions) {
365 guarantee(_from_card_cache == NULL, "Should not call this multiple times");
366
367 // Pad rows to cache line sizes.
368 static const int ints_per_cache_line = DEFAULT_CACHE_LINE_SIZE / sizeof(int);
369 int n_par_rs = HeapRegionRemSet::num_par_rem_sets();
370 _from_card_cache_max_regions = align_size_up(max_regions, ints_per_cache_line);
371
372 // Need to make sure that the arrays are aligned too. Allocate a suitably
373 // large array to be able to align its base address later. We do not store
374 // the old pointer as we never free that memory.
375 size_t num_ints_to_alloc = n_par_rs * _from_card_cache_max_regions + ints_per_cache_line - 1;
376 int* data = NEW_C_HEAP_ARRAY(int, num_ints_to_alloc, mtGC);
377 data = (int*) (align_size_up_((uintptr_t)data, DEFAULT_CACHE_LINE_SIZE));
378
379 _from_card_cache = NEW_C_HEAP_ARRAY(int*, n_par_rs, mtGC);
380 for (int i = 0; i < n_par_rs; i++) {
381 _from_card_cache[i] = data + i * _from_card_cache_max_regions;
382 for (size_t j = 0; j < _from_card_cache_max_regions; j++) {
383 _from_card_cache[i][j] = -1; // An invalid value.
384 }
385 }
386 _from_card_cache_mem_size = num_ints_to_alloc * sizeof(int);
387 }
388
389 void OtherRegionsTable::shrink_from_card_cache(size_t new_n_regs) {
390 for (int i = 0; i < HeapRegionRemSet::num_par_rem_sets(); i++) {
391 assert(new_n_regs <= _from_card_cache_max_regions, "Must be within max.");
392 for (size_t j = new_n_regs; j < _from_card_cache_max_regions; j++) {
393 _from_card_cache[i][j] = -1; // An invalid value.
394 }
395 }
396 }
397
398 #ifndef PRODUCT
399 void OtherRegionsTable::print_from_card_cache() {
400 for (int i = 0; i < HeapRegionRemSet::num_par_rem_sets(); i++) {
401 for (size_t j = 0; j < _from_card_cache_max_regions; j++) {
402 gclog_or_tty->print_cr("_from_card_cache[%d][%d] = %d.",
403 i, j, _from_card_cache[i][j]);
404 }
405 }
406 }
407 #endif
408
409 void OtherRegionsTable::add_reference(OopOrNarrowOopStar from, int tid) {
410 size_t cur_hrs_ind = (size_t) hr()->hrs_index();
411
412 if (G1TraceHeapRegionRememberedSet) {
413 gclog_or_tty->print_cr("ORT::add_reference_work(" PTR_FORMAT "->" PTR_FORMAT ").",
414 from,
415 UseCompressedOops
416 ? (void *)oopDesc::load_decode_heap_oop((narrowOop*)from)
417 : (void *)oopDesc::load_decode_heap_oop((oop*)from));
418 }
419
420 int from_card = (int)(uintptr_t(from) >> CardTableModRefBS::card_shift);
421
422 if (G1TraceHeapRegionRememberedSet) {
423 gclog_or_tty->print_cr("Table for [" PTR_FORMAT "...): card %d (cache = %d)",
424 hr()->bottom(), from_card,
425 _from_card_cache[tid][cur_hrs_ind]);
426 }
427
428 if (from_card == _from_card_cache[tid][cur_hrs_ind]) {
429 if (G1TraceHeapRegionRememberedSet) {
430 gclog_or_tty->print_cr(" from-card cache hit.");
431 }
432 assert(contains_reference(from), "We just added it!");
433 return;
434 } else {
435 _from_card_cache[tid][cur_hrs_ind] = from_card;
436 }
437
438 // Note that this may be a continued H region.
439 HeapRegion* from_hr = _g1h->heap_region_containing_raw(from);
440 RegionIdx_t from_hrs_ind = (RegionIdx_t) from_hr->hrs_index();
441
442 // If the region is already coarsened, return.
443 if (_coarse_map.at(from_hrs_ind)) {
444 if (G1TraceHeapRegionRememberedSet) {
445 gclog_or_tty->print_cr(" coarse map hit.");
446 }
447 assert(contains_reference(from), "We just added it!");
448 return;
449 }
450
451 // Otherwise find a per-region table to add it to.
452 size_t ind = from_hrs_ind & _mod_max_fine_entries_mask;
453 PerRegionTable* prt = find_region_table(ind, from_hr);
454 if (prt == NULL) {
455 MutexLockerEx x(_m, Mutex::_no_safepoint_check_flag);
456 // Confirm that it's really not there...
457 prt = find_region_table(ind, from_hr);
458 if (prt == NULL) {
459
460 uintptr_t from_hr_bot_card_index =
461 uintptr_t(from_hr->bottom())
462 >> CardTableModRefBS::card_shift;
463 CardIdx_t card_index = from_card - from_hr_bot_card_index;
464 assert(0 <= card_index && (size_t)card_index < HeapRegion::CardsPerRegion,
465 "Must be in range.");
466 if (G1HRRSUseSparseTable &&
467 _sparse_table.add_card(from_hrs_ind, card_index)) {
468 if (G1RecordHRRSOops) {
469 HeapRegionRemSet::record(hr(), from);
470 if (G1TraceHeapRegionRememberedSet) {
471 gclog_or_tty->print(" Added card " PTR_FORMAT " to region "
472 "[" PTR_FORMAT "...) for ref " PTR_FORMAT ".\n",
473 align_size_down(uintptr_t(from),
474 CardTableModRefBS::card_size),
475 hr()->bottom(), from);
476 }
477 }
478 if (G1TraceHeapRegionRememberedSet) {
479 gclog_or_tty->print_cr(" added card to sparse table.");
480 }
481 assert(contains_reference_locked(from), "We just added it!");
482 return;
483 } else {
484 if (G1TraceHeapRegionRememberedSet) {
485 gclog_or_tty->print_cr(" [tid %d] sparse table entry "
486 "overflow(f: %d, t: %d)",
487 tid, from_hrs_ind, cur_hrs_ind);
488 }
489 }
490
491 if (_n_fine_entries == _max_fine_entries) {
492 prt = delete_region_table();
493 // There is no need to clear the links to the 'all' list here:
494 // prt will be reused immediately, i.e. remain in the 'all' list.
495 prt->init(from_hr, false /* clear_links_to_all_list */);
496 } else {
497 prt = PerRegionTable::alloc(from_hr);
498 link_to_all(prt);
499 }
500
501 PerRegionTable* first_prt = _fine_grain_regions[ind];
502 prt->set_collision_list_next(first_prt);
503 _fine_grain_regions[ind] = prt;
504 _n_fine_entries++;
505
506 if (G1HRRSUseSparseTable) {
507 // Transfer from sparse to fine-grain.
508 SparsePRTEntry *sprt_entry = _sparse_table.get_entry(from_hrs_ind);
509 assert(sprt_entry != NULL, "There should have been an entry");
510 for (int i = 0; i < SparsePRTEntry::cards_num(); i++) {
511 CardIdx_t c = sprt_entry->card(i);
512 if (c != SparsePRTEntry::NullEntry) {
513 prt->add_card(c);
514 }
515 }
516 // Now we can delete the sparse entry.
517 bool res = _sparse_table.delete_entry(from_hrs_ind);
518 assert(res, "It should have been there.");
519 }
520 }
521 assert(prt != NULL && prt->hr() == from_hr, "consequence");
522 }
523 // Note that we can't assert "prt->hr() == from_hr", because of the
524 // possibility of concurrent reuse. But see head comment of
525 // OtherRegionsTable for why this is OK.
526 assert(prt != NULL, "Inv");
527
528 prt->add_reference(from);
529
530 if (G1RecordHRRSOops) {
531 HeapRegionRemSet::record(hr(), from);
532 if (G1TraceHeapRegionRememberedSet) {
533 gclog_or_tty->print("Added card " PTR_FORMAT " to region "
534 "[" PTR_FORMAT "...) for ref " PTR_FORMAT ".\n",
535 align_size_down(uintptr_t(from),
536 CardTableModRefBS::card_size),
537 hr()->bottom(), from);
538 }
539 }
540 assert(contains_reference(from), "We just added it!");
541 }
542
543 PerRegionTable*
544 OtherRegionsTable::find_region_table(size_t ind, HeapRegion* hr) const {
545 assert(0 <= ind && ind < _max_fine_entries, "Preconditions.");
546 PerRegionTable* prt = _fine_grain_regions[ind];
547 while (prt != NULL && prt->hr() != hr) {
548 prt = prt->collision_list_next();
549 }
550 // Loop postcondition is the method postcondition.
551 return prt;
552 }
553
554 jint OtherRegionsTable::_n_coarsenings = 0;
555
556 PerRegionTable* OtherRegionsTable::delete_region_table() {
557 assert(_m->owned_by_self(), "Precondition");
558 assert(_n_fine_entries == _max_fine_entries, "Precondition");
559 PerRegionTable* max = NULL;
560 jint max_occ = 0;
561 PerRegionTable** max_prev;
562 size_t max_ind;
563
564 size_t i = _fine_eviction_start;
565 for (size_t k = 0; k < _fine_eviction_sample_size; k++) {
566 size_t ii = i;
567 // Make sure we get a non-NULL sample.
568 while (_fine_grain_regions[ii] == NULL) {
569 ii++;
570 if (ii == _max_fine_entries) ii = 0;
571 guarantee(ii != i, "We must find one.");
572 }
573 PerRegionTable** prev = &_fine_grain_regions[ii];
574 PerRegionTable* cur = *prev;
575 while (cur != NULL) {
576 jint cur_occ = cur->occupied();
577 if (max == NULL || cur_occ > max_occ) {
578 max = cur;
579 max_prev = prev;
580 max_ind = i;
581 max_occ = cur_occ;
582 }
583 prev = cur->collision_list_next_addr();
584 cur = cur->collision_list_next();
585 }
586 i = i + _fine_eviction_stride;
587 if (i >= _n_fine_entries) i = i - _n_fine_entries;
588 }
589
590 _fine_eviction_start++;
591
592 if (_fine_eviction_start >= _n_fine_entries) {
593 _fine_eviction_start -= _n_fine_entries;
594 }
595
596 guarantee(max != NULL, "Since _n_fine_entries > 0");
597
598 // Set the corresponding coarse bit.
599 size_t max_hrs_index = (size_t) max->hr()->hrs_index();
600 if (!_coarse_map.at(max_hrs_index)) {
601 _coarse_map.at_put(max_hrs_index, true);
602 _n_coarse_entries++;
603 if (G1TraceHeapRegionRememberedSet) {
604 gclog_or_tty->print("Coarsened entry in region [" PTR_FORMAT "...] "
605 "for region [" PTR_FORMAT "...] (%d coarse entries).\n",
606 hr()->bottom(),
607 max->hr()->bottom(),
608 _n_coarse_entries);
609 }
610 }
611
612 // Unsplice.
613 *max_prev = max->collision_list_next();
614 Atomic::inc(&_n_coarsenings);
615 _n_fine_entries--;
616 return max;
617 }
618
619
620 // At present, this must be called stop-world single-threaded.
621 void OtherRegionsTable::scrub(CardTableModRefBS* ctbs,
622 BitMap* region_bm, BitMap* card_bm) {
623 // First eliminated garbage regions from the coarse map.
624 if (G1RSScrubVerbose) {
625 gclog_or_tty->print_cr("Scrubbing region %u:", hr()->hrs_index());
626 }
627
628 assert(_coarse_map.size() == region_bm->size(), "Precondition");
629 if (G1RSScrubVerbose) {
630 gclog_or_tty->print(" Coarse map: before = "SIZE_FORMAT"...",
631 _n_coarse_entries);
632 }
633 _coarse_map.set_intersection(*region_bm);
634 _n_coarse_entries = _coarse_map.count_one_bits();
635 if (G1RSScrubVerbose) {
636 gclog_or_tty->print_cr(" after = "SIZE_FORMAT".", _n_coarse_entries);
637 }
638
639 // Now do the fine-grained maps.
640 for (size_t i = 0; i < _max_fine_entries; i++) {
641 PerRegionTable* cur = _fine_grain_regions[i];
642 PerRegionTable** prev = &_fine_grain_regions[i];
643 while (cur != NULL) {
644 PerRegionTable* nxt = cur->collision_list_next();
645 // If the entire region is dead, eliminate.
646 if (G1RSScrubVerbose) {
647 gclog_or_tty->print_cr(" For other region %u:",
648 cur->hr()->hrs_index());
649 }
650 if (!region_bm->at((size_t) cur->hr()->hrs_index())) {
651 *prev = nxt;
652 cur->set_collision_list_next(NULL);
653 _n_fine_entries--;
654 if (G1RSScrubVerbose) {
655 gclog_or_tty->print_cr(" deleted via region map.");
656 }
657 unlink_from_all(cur);
658 PerRegionTable::free(cur);
659 } else {
660 // Do fine-grain elimination.
661 if (G1RSScrubVerbose) {
662 gclog_or_tty->print(" occ: before = %4d.", cur->occupied());
663 }
664 cur->scrub(ctbs, card_bm);
665 if (G1RSScrubVerbose) {
666 gclog_or_tty->print_cr(" after = %4d.", cur->occupied());
667 }
668 // Did that empty the table completely?
669 if (cur->occupied() == 0) {
670 *prev = nxt;
671 cur->set_collision_list_next(NULL);
672 _n_fine_entries--;
673 unlink_from_all(cur);
674 PerRegionTable::free(cur);
675 } else {
676 prev = cur->collision_list_next_addr();
677 }
678 }
679 cur = nxt;
680 }
681 }
682 // Since we may have deleted a from_card_cache entry from the RS, clear
683 // the FCC.
684 clear_fcc();
685 }
686
687
688 size_t OtherRegionsTable::occupied() const {
689 size_t sum = occ_fine();
690 sum += occ_sparse();
691 sum += occ_coarse();
692 return sum;
693 }
694
695 size_t OtherRegionsTable::occ_fine() const {
696 size_t sum = 0;
697
698 size_t num = 0;
699 PerRegionTable * cur = _first_all_fine_prts;
700 while (cur != NULL) {
701 sum += cur->occupied();
702 cur = cur->next();
703 num++;
704 }
705 guarantee(num == _n_fine_entries, "just checking");
706 return sum;
707 }
708
709 size_t OtherRegionsTable::occ_coarse() const {
710 return (_n_coarse_entries * HeapRegion::CardsPerRegion);
711 }
712
713 size_t OtherRegionsTable::occ_sparse() const {
714 return _sparse_table.occupied();
715 }
716
717 size_t OtherRegionsTable::mem_size() const {
718 size_t sum = 0;
719 // all PRTs are of the same size so it is sufficient to query only one of them.
720 if (_first_all_fine_prts != NULL) {
721 assert(_last_all_fine_prts != NULL &&
722 _first_all_fine_prts->mem_size() == _last_all_fine_prts->mem_size(), "check that mem_size() is constant");
723 sum += _first_all_fine_prts->mem_size() * _n_fine_entries;
724 }
725 sum += (sizeof(PerRegionTable*) * _max_fine_entries);
726 sum += (_coarse_map.size_in_words() * HeapWordSize);
727 sum += (_sparse_table.mem_size());
728 sum += sizeof(*this) - sizeof(_sparse_table); // Avoid double counting above.
729 return sum;
730 }
731
732 size_t OtherRegionsTable::static_mem_size() {
733 return _from_card_cache_mem_size;
734 }
735
736 size_t OtherRegionsTable::fl_mem_size() {
737 return PerRegionTable::fl_mem_size();
738 }
739
740 void OtherRegionsTable::clear_fcc() {
741 size_t hrs_idx = hr()->hrs_index();
742 uint num_par_remsets = HeapRegionRemSet::num_par_rem_sets();
743 for (uint i = 0; i < num_par_remsets; i++) {
744 _from_card_cache[i][hrs_idx] = -1;
745 }
746 }
747
748 void OtherRegionsTable::clear() {
749 // if there are no entries, skip this step
750 if (_first_all_fine_prts != NULL) {
751 guarantee(_first_all_fine_prts != NULL && _last_all_fine_prts != NULL, "just checking");
752 PerRegionTable::bulk_free(_first_all_fine_prts, _last_all_fine_prts);
753 memset(_fine_grain_regions, 0, _max_fine_entries * sizeof(_fine_grain_regions[0]));
754 } else {
755 guarantee(_first_all_fine_prts == NULL && _last_all_fine_prts == NULL, "just checking");
756 }
757
758 _first_all_fine_prts = _last_all_fine_prts = NULL;
759 _sparse_table.clear();
760 _coarse_map.clear();
761 _n_fine_entries = 0;
762 _n_coarse_entries = 0;
763
764 clear_fcc();
765 }
766
767 void OtherRegionsTable::clear_incoming_entry(HeapRegion* from_hr) {
768 MutexLockerEx x(_m, Mutex::_no_safepoint_check_flag);
769 size_t hrs_ind = (size_t) from_hr->hrs_index();
770 size_t ind = hrs_ind & _mod_max_fine_entries_mask;
771 if (del_single_region_table(ind, from_hr)) {
772 assert(!_coarse_map.at(hrs_ind), "Inv");
773 } else {
774 _coarse_map.par_at_put(hrs_ind, 0);
775 }
776 // Check to see if any of the fcc entries come from here.
777 size_t hr_ind = (size_t) hr()->hrs_index();
778 for (int tid = 0; tid < HeapRegionRemSet::num_par_rem_sets(); tid++) {
779 int fcc_ent = _from_card_cache[tid][hr_ind];
780 if (fcc_ent != -1) {
781 HeapWord* card_addr = (HeapWord*)
782 (uintptr_t(fcc_ent) << CardTableModRefBS::card_shift);
783 if (hr()->is_in_reserved(card_addr)) {
784 // Clear the from card cache.
785 _from_card_cache[tid][hr_ind] = -1;
786 }
787 }
788 }
789 }
790
791 bool OtherRegionsTable::del_single_region_table(size_t ind,
792 HeapRegion* hr) {
793 assert(0 <= ind && ind < _max_fine_entries, "Preconditions.");
794 PerRegionTable** prev_addr = &_fine_grain_regions[ind];
795 PerRegionTable* prt = *prev_addr;
796 while (prt != NULL && prt->hr() != hr) {
797 prev_addr = prt->collision_list_next_addr();
798 prt = prt->collision_list_next();
799 }
800 if (prt != NULL) {
801 assert(prt->hr() == hr, "Loop postcondition.");
802 *prev_addr = prt->collision_list_next();
803 unlink_from_all(prt);
804 PerRegionTable::free(prt);
805 _n_fine_entries--;
806 return true;
807 } else {
808 return false;
809 }
810 }
811
812 bool OtherRegionsTable::contains_reference(OopOrNarrowOopStar from) const {
813 // Cast away const in this case.
814 MutexLockerEx x((Mutex*)_m, Mutex::_no_safepoint_check_flag);
815 return contains_reference_locked(from);
816 }
817
818 bool OtherRegionsTable::contains_reference_locked(OopOrNarrowOopStar from) const {
819 HeapRegion* hr = _g1h->heap_region_containing_raw(from);
820 if (hr == NULL) return false;
821 RegionIdx_t hr_ind = (RegionIdx_t) hr->hrs_index();
822 // Is this region in the coarse map?
823 if (_coarse_map.at(hr_ind)) return true;
824
825 PerRegionTable* prt = find_region_table(hr_ind & _mod_max_fine_entries_mask,
826 hr);
827 if (prt != NULL) {
828 return prt->contains_reference(from);
829
830 } else {
831 uintptr_t from_card =
832 (uintptr_t(from) >> CardTableModRefBS::card_shift);
833 uintptr_t hr_bot_card_index =
834 uintptr_t(hr->bottom()) >> CardTableModRefBS::card_shift;
835 assert(from_card >= hr_bot_card_index, "Inv");
836 CardIdx_t card_index = from_card - hr_bot_card_index;
837 assert(0 <= card_index && (size_t)card_index < HeapRegion::CardsPerRegion,
838 "Must be in range.");
839 return _sparse_table.contains_card(hr_ind, card_index);
840 }
841
842
843 }
844
845 void
846 OtherRegionsTable::do_cleanup_work(HRRSCleanupTask* hrrs_cleanup_task) {
847 _sparse_table.do_cleanup_work(hrrs_cleanup_task);
848 }
849
850 // Determines how many threads can add records to an rset in parallel.
851 // This can be done by either mutator threads together with the
852 // concurrent refinement threads or GC threads.
853 int HeapRegionRemSet::num_par_rem_sets() {
854 return (int)MAX2(DirtyCardQueueSet::num_par_ids() + ConcurrentG1Refine::thread_num(), ParallelGCThreads);
855 }
856
857 HeapRegionRemSet::HeapRegionRemSet(G1BlockOffsetSharedArray* bosa,
858 HeapRegion* hr)
859 : _bosa(bosa),
860 _m(Mutex::leaf, FormatBuffer<128>("HeapRegionRemSet lock #"UINT32_FORMAT, hr->hrs_index()), true),
861 _code_roots(), _other_regions(hr, &_m) {
862 reset_for_par_iteration();
863 }
864
865 void HeapRegionRemSet::setup_remset_size() {
866 // Setup sparse and fine-grain tables sizes.
867 // table_size = base * (log(region_size / 1M) + 1)
868 const int LOG_M = 20;
869 int region_size_log_mb = MAX2(HeapRegion::LogOfHRGrainBytes - LOG_M, 0);
870 if (FLAG_IS_DEFAULT(G1RSetSparseRegionEntries)) {
871 G1RSetSparseRegionEntries = G1RSetSparseRegionEntriesBase * (region_size_log_mb + 1);
872 }
873 if (FLAG_IS_DEFAULT(G1RSetRegionEntries)) {
874 G1RSetRegionEntries = G1RSetRegionEntriesBase * (region_size_log_mb + 1);
875 }
876 guarantee(G1RSetSparseRegionEntries > 0 && G1RSetRegionEntries > 0 , "Sanity");
877 }
878
879 bool HeapRegionRemSet::claim_iter() {
880 if (_iter_state != Unclaimed) return false;
881 jint res = Atomic::cmpxchg(Claimed, (jint*)(&_iter_state), Unclaimed);
882 return (res == Unclaimed);
883 }
884
885 void HeapRegionRemSet::set_iter_complete() {
886 _iter_state = Complete;
887 }
888
889 bool HeapRegionRemSet::iter_is_complete() {
890 return _iter_state == Complete;
891 }
892
893 #ifndef PRODUCT
894 void HeapRegionRemSet::print() {
895 HeapRegionRemSetIterator iter(this);
896 size_t card_index;
897 while (iter.has_next(card_index)) {
898 HeapWord* card_start =
899 G1CollectedHeap::heap()->bot_shared()->address_for_index(card_index);
900 gclog_or_tty->print_cr(" Card " PTR_FORMAT, card_start);
901 }
902 if (iter.n_yielded() != occupied()) {
903 gclog_or_tty->print_cr("Yielded disagrees with occupied:");
904 gclog_or_tty->print_cr(" %6d yielded (%6d coarse, %6d fine).",
905 iter.n_yielded(),
906 iter.n_yielded_coarse(), iter.n_yielded_fine());
907 gclog_or_tty->print_cr(" %6d occ (%6d coarse, %6d fine).",
908 occupied(), occ_coarse(), occ_fine());
909 }
910 guarantee(iter.n_yielded() == occupied(),
911 "We should have yielded all the represented cards.");
912 }
913 #endif
914
915 void HeapRegionRemSet::cleanup() {
916 SparsePRT::cleanup_all();
917 }
918
919 void HeapRegionRemSet::clear() {
920 MutexLockerEx x(&_m, Mutex::_no_safepoint_check_flag);
921 clear_locked();
922 }
923
924 void HeapRegionRemSet::clear_locked() {
925 _code_roots.clear();
926 _other_regions.clear();
927 assert(occupied_locked() == 0, "Should be clear.");
928 reset_for_par_iteration();
929 }
930
931 void HeapRegionRemSet::reset_for_par_iteration() {
932 _iter_state = Unclaimed;
933 _iter_claimed = 0;
934 // It's good to check this to make sure that the two methods are in sync.
935 assert(verify_ready_for_par_iteration(), "post-condition");
936 }
937
938 void HeapRegionRemSet::scrub(CardTableModRefBS* ctbs,
939 BitMap* region_bm, BitMap* card_bm) {
940 _other_regions.scrub(ctbs, region_bm, card_bm);
941 }
942
943
944 // Code roots support
945
946 void HeapRegionRemSet::add_strong_code_root(nmethod* nm) {
947 assert(nm != NULL, "sanity");
948 _code_roots.add(nm);
949 }
950
951 void HeapRegionRemSet::remove_strong_code_root(nmethod* nm) {
952 assert(nm != NULL, "sanity");
953 _code_roots.remove(nm);
954 // Check that there were no duplicates
955 guarantee(!_code_roots.contains(nm), "duplicate entry found");
956 }
957
958 class NMethodMigrationOopClosure : public OopClosure {
959 G1CollectedHeap* _g1h;
960 HeapRegion* _from;
961 nmethod* _nm;
962
963 uint _num_self_forwarded;
964
965 template <class T> void do_oop_work(T* p) {
966 T heap_oop = oopDesc::load_heap_oop(p);
967 if (!oopDesc::is_null(heap_oop)) {
968 oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
969 if (_from->is_in(obj)) {
970 // Reference still points into the source region.
971 // Since roots are immediately evacuated this means that
972 // we must have self forwarded the object
973 assert(obj->is_forwarded(),
974 err_msg("code roots should be immediately evacuated. "
975 "Ref: "PTR_FORMAT", "
976 "Obj: "PTR_FORMAT", "
977 "Region: "HR_FORMAT,
978 p, (void*) obj, HR_FORMAT_PARAMS(_from)));
979 assert(obj->forwardee() == obj,
980 err_msg("not self forwarded? obj = "PTR_FORMAT, (void*)obj));
981
982 // The object has been self forwarded.
983 // Note, if we're during an initial mark pause, there is
984 // no need to explicitly mark object. It will be marked
985 // during the regular evacuation failure handling code.
986 _num_self_forwarded++;
987 } else {
988 // The reference points into a promotion or to-space region
989 HeapRegion* to = _g1h->heap_region_containing(obj);
990 to->rem_set()->add_strong_code_root(_nm);
991 }
992 }
993 }
994
995 public:
996 NMethodMigrationOopClosure(G1CollectedHeap* g1h, HeapRegion* from, nmethod* nm):
997 _g1h(g1h), _from(from), _nm(nm), _num_self_forwarded(0) {}
998
999 void do_oop(narrowOop* p) { do_oop_work(p); }
1000 void do_oop(oop* p) { do_oop_work(p); }
1001
1002 uint retain() { return _num_self_forwarded > 0; }
1003 };
1004
1005 void HeapRegionRemSet::migrate_strong_code_roots() {
1006 assert(hr()->in_collection_set(), "only collection set regions");
1007 assert(!hr()->isHumongous(),
1008 err_msg("humongous region "HR_FORMAT" should not have been added to the collection set",
1009 HR_FORMAT_PARAMS(hr())));
1010
1011 ResourceMark rm;
1012
1013 // List of code blobs to retain for this region
1014 GrowableArray<nmethod*> to_be_retained(10);
1015 G1CollectedHeap* g1h = G1CollectedHeap::heap();
1016
1017 while (!_code_roots.is_empty()) {
1018 nmethod *nm = _code_roots.pop();
1019 if (nm != NULL) {
1020 NMethodMigrationOopClosure oop_cl(g1h, hr(), nm);
1021 nm->oops_do(&oop_cl);
1022 if (oop_cl.retain()) {
1023 to_be_retained.push(nm);
1024 }
1025 }
1026 }
1027
1028 // Now push any code roots we need to retain
1029 assert(to_be_retained.is_empty() || hr()->evacuation_failed(),
1030 "Retained nmethod list must be empty or "
1031 "evacuation of this region failed");
1032
1033 while (to_be_retained.is_nonempty()) {
1034 nmethod* nm = to_be_retained.pop();
1035 assert(nm != NULL, "sanity");
1036 add_strong_code_root(nm);
1037 }
1038 }
1039
1040 void HeapRegionRemSet::strong_code_roots_do(CodeBlobClosure* blk) const {
1041 _code_roots.nmethods_do(blk);
1042 }
1043
1044 size_t HeapRegionRemSet::strong_code_roots_mem_size() {
1045 return _code_roots.mem_size();
1046 }
1047
1048 //-------------------- Iteration --------------------
1049
1050 HeapRegionRemSetIterator:: HeapRegionRemSetIterator(HeapRegionRemSet* hrrs) :
1051 _hrrs(hrrs),
1052 _g1h(G1CollectedHeap::heap()),
1053 _coarse_map(&hrrs->_other_regions._coarse_map),
1054 _fine_grain_regions(hrrs->_other_regions._fine_grain_regions),
1055 _bosa(hrrs->bosa()),
1056 _is(Sparse),
1057 // Set these values so that we increment to the first region.
1058 _coarse_cur_region_index(-1),
1059 _coarse_cur_region_cur_card(HeapRegion::CardsPerRegion-1),
1060 _cur_region_cur_card(0),
1061 _fine_array_index(-1),
1062 _fine_cur_prt(NULL),
1063 _n_yielded_coarse(0),
1064 _n_yielded_fine(0),
1065 _n_yielded_sparse(0),
1066 _sparse_iter(&hrrs->_other_regions._sparse_table) {}
1067
1068 bool HeapRegionRemSetIterator::coarse_has_next(size_t& card_index) {
1069 if (_hrrs->_other_regions._n_coarse_entries == 0) return false;
1070 // Go to the next card.
1071 _coarse_cur_region_cur_card++;
1072 // Was the last the last card in the current region?
1073 if (_coarse_cur_region_cur_card == HeapRegion::CardsPerRegion) {
1074 // Yes: find the next region. This may leave _coarse_cur_region_index
1075 // Set to the last index, in which case there are no more coarse
1076 // regions.
1077 _coarse_cur_region_index =
1078 (int) _coarse_map->get_next_one_offset(_coarse_cur_region_index + 1);
1079 if ((size_t)_coarse_cur_region_index < _coarse_map->size()) {
1080 _coarse_cur_region_cur_card = 0;
1081 HeapWord* r_bot =
1082 _g1h->region_at((uint) _coarse_cur_region_index)->bottom();
1083 _cur_region_card_offset = _bosa->index_for(r_bot);
1084 } else {
1085 return false;
1086 }
1087 }
1088 // If we didn't return false above, then we can yield a card.
1089 card_index = _cur_region_card_offset + _coarse_cur_region_cur_card;
1090 return true;
1091 }
1092
1093 void HeapRegionRemSetIterator::fine_find_next_non_null_prt() {
1094 // Otherwise, find the next bucket list in the array.
1095 _fine_array_index++;
1096 while (_fine_array_index < (int) OtherRegionsTable::_max_fine_entries) {
1097 _fine_cur_prt = _fine_grain_regions[_fine_array_index];
1098 if (_fine_cur_prt != NULL) return;
1099 else _fine_array_index++;
1100 }
1101 assert(_fine_cur_prt == NULL, "Loop post");
1102 }
1103
1104 bool HeapRegionRemSetIterator::fine_has_next(size_t& card_index) {
1105 if (fine_has_next()) {
1106 _cur_region_cur_card =
1107 _fine_cur_prt->_bm.get_next_one_offset(_cur_region_cur_card + 1);
1108 }
1109 while (!fine_has_next()) {
1110 if (_cur_region_cur_card == (size_t) HeapRegion::CardsPerRegion) {
1111 _cur_region_cur_card = 0;
1112 _fine_cur_prt = _fine_cur_prt->collision_list_next();
1113 }
1114 if (_fine_cur_prt == NULL) {
1115 fine_find_next_non_null_prt();
1116 if (_fine_cur_prt == NULL) return false;
1117 }
1118 assert(_fine_cur_prt != NULL && _cur_region_cur_card == 0,
1119 "inv.");
1120 HeapWord* r_bot =
1121 _fine_cur_prt->hr()->bottom();
1122 _cur_region_card_offset = _bosa->index_for(r_bot);
1123 _cur_region_cur_card = _fine_cur_prt->_bm.get_next_one_offset(0);
1124 }
1125 assert(fine_has_next(), "Or else we exited the loop via the return.");
1126 card_index = _cur_region_card_offset + _cur_region_cur_card;
1127 return true;
1128 }
1129
1130 bool HeapRegionRemSetIterator::fine_has_next() {
1131 return
1132 _fine_cur_prt != NULL &&
1133 _cur_region_cur_card < HeapRegion::CardsPerRegion;
1134 }
1135
1136 bool HeapRegionRemSetIterator::has_next(size_t& card_index) {
1137 switch (_is) {
1138 case Sparse:
1139 if (_sparse_iter.has_next(card_index)) {
1140 _n_yielded_sparse++;
1141 return true;
1142 }
1143 // Otherwise, deliberate fall-through
1144 _is = Fine;
1145 case Fine:
1146 if (fine_has_next(card_index)) {
1147 _n_yielded_fine++;
1148 return true;
1149 }
1150 // Otherwise, deliberate fall-through
1151 _is = Coarse;
1152 case Coarse:
1153 if (coarse_has_next(card_index)) {
1154 _n_yielded_coarse++;
1155 return true;
1156 }
1157 // Otherwise...
1158 break;
1159 }
1160 assert(ParallelGCThreads > 1 ||
1161 n_yielded() == _hrrs->occupied(),
1162 "Should have yielded all the cards in the rem set "
1163 "(in the non-par case).");
1164 return false;
1165 }
1166
1167
1168
1169 OopOrNarrowOopStar* HeapRegionRemSet::_recorded_oops = NULL;
1170 HeapWord** HeapRegionRemSet::_recorded_cards = NULL;
1171 HeapRegion** HeapRegionRemSet::_recorded_regions = NULL;
1172 int HeapRegionRemSet::_n_recorded = 0;
1173
1174 HeapRegionRemSet::Event* HeapRegionRemSet::_recorded_events = NULL;
1175 int* HeapRegionRemSet::_recorded_event_index = NULL;
1176 int HeapRegionRemSet::_n_recorded_events = 0;
1177
1178 void HeapRegionRemSet::record(HeapRegion* hr, OopOrNarrowOopStar f) {
1179 if (_recorded_oops == NULL) {
1180 assert(_n_recorded == 0
1181 && _recorded_cards == NULL
1182 && _recorded_regions == NULL,
1183 "Inv");
1184 _recorded_oops = NEW_C_HEAP_ARRAY(OopOrNarrowOopStar, MaxRecorded, mtGC);
1185 _recorded_cards = NEW_C_HEAP_ARRAY(HeapWord*, MaxRecorded, mtGC);
1186 _recorded_regions = NEW_C_HEAP_ARRAY(HeapRegion*, MaxRecorded, mtGC);
1187 }
1188 if (_n_recorded == MaxRecorded) {
1189 gclog_or_tty->print_cr("Filled up 'recorded' (%d).", MaxRecorded);
1190 } else {
1191 _recorded_cards[_n_recorded] =
1192 (HeapWord*)align_size_down(uintptr_t(f),
1193 CardTableModRefBS::card_size);
1194 _recorded_oops[_n_recorded] = f;
1195 _recorded_regions[_n_recorded] = hr;
1196 _n_recorded++;
1197 }
1198 }
1199
1200 void HeapRegionRemSet::record_event(Event evnt) {
1201 if (!G1RecordHRRSEvents) return;
1202
1203 if (_recorded_events == NULL) {
1204 assert(_n_recorded_events == 0
1205 && _recorded_event_index == NULL,
1206 "Inv");
1207 _recorded_events = NEW_C_HEAP_ARRAY(Event, MaxRecordedEvents, mtGC);
1208 _recorded_event_index = NEW_C_HEAP_ARRAY(int, MaxRecordedEvents, mtGC);
1209 }
1210 if (_n_recorded_events == MaxRecordedEvents) {
1211 gclog_or_tty->print_cr("Filled up 'recorded_events' (%d).", MaxRecordedEvents);
1212 } else {
1213 _recorded_events[_n_recorded_events] = evnt;
1214 _recorded_event_index[_n_recorded_events] = _n_recorded;
1215 _n_recorded_events++;
1216 }
1217 }
1218
1219 void HeapRegionRemSet::print_event(outputStream* str, Event evnt) {
1220 switch (evnt) {
1221 case Event_EvacStart:
1222 str->print("Evac Start");
1223 break;
1224 case Event_EvacEnd:
1225 str->print("Evac End");
1226 break;
1227 case Event_RSUpdateEnd:
1228 str->print("RS Update End");
1229 break;
1230 }
1231 }
1232
1233 void HeapRegionRemSet::print_recorded() {
1234 int cur_evnt = 0;
1235 Event cur_evnt_kind;
1236 int cur_evnt_ind = 0;
1237 if (_n_recorded_events > 0) {
1238 cur_evnt_kind = _recorded_events[cur_evnt];
1239 cur_evnt_ind = _recorded_event_index[cur_evnt];
1240 }
1241
1242 for (int i = 0; i < _n_recorded; i++) {
1243 while (cur_evnt < _n_recorded_events && i == cur_evnt_ind) {
1244 gclog_or_tty->print("Event: ");
1245 print_event(gclog_or_tty, cur_evnt_kind);
1246 gclog_or_tty->print_cr("");
1247 cur_evnt++;
1248 if (cur_evnt < MaxRecordedEvents) {
1249 cur_evnt_kind = _recorded_events[cur_evnt];
1250 cur_evnt_ind = _recorded_event_index[cur_evnt];
1251 }
1252 }
1253 gclog_or_tty->print("Added card " PTR_FORMAT " to region [" PTR_FORMAT "...]"
1254 " for ref " PTR_FORMAT ".\n",
1255 _recorded_cards[i], _recorded_regions[i]->bottom(),
1256 _recorded_oops[i]);
1257 }
1258 }
1259
1260 void HeapRegionRemSet::reset_for_cleanup_tasks() {
1261 SparsePRT::reset_for_cleanup_tasks();
1262 }
1263
1264 void HeapRegionRemSet::do_cleanup_work(HRRSCleanupTask* hrrs_cleanup_task) {
1265 _other_regions.do_cleanup_work(hrrs_cleanup_task);
1266 }
1267
1268 void
1269 HeapRegionRemSet::finish_cleanup_task(HRRSCleanupTask* hrrs_cleanup_task) {
1270 SparsePRT::finish_cleanup_task(hrrs_cleanup_task);
1271 }
1272
1273 #ifndef PRODUCT
1274 void PerRegionTable::test_fl_mem_size() {
1275 PerRegionTable* dummy = alloc(NULL);
1276 free(dummy);
1277 guarantee(dummy->mem_size() == fl_mem_size(), "fl_mem_size() does not return the correct element size");
1278 // try to reset the state
1279 _free_list = NULL;
1280 delete dummy;
1281 }
1282
1283 void HeapRegionRemSet::test_prt() {
1284 PerRegionTable::test_fl_mem_size();
1285 }
1286
1287 void HeapRegionRemSet::test() {
1288 os::sleep(Thread::current(), (jlong)5000, false);
1289 G1CollectedHeap* g1h = G1CollectedHeap::heap();
1290
1291 // Run with "-XX:G1LogRSetRegionEntries=2", so that 1 and 5 end up in same
1292 // hash bucket.
1293 HeapRegion* hr0 = g1h->region_at(0);
1294 HeapRegion* hr1 = g1h->region_at(1);
1295 HeapRegion* hr2 = g1h->region_at(5);
1296 HeapRegion* hr3 = g1h->region_at(6);
1297 HeapRegion* hr4 = g1h->region_at(7);
1298 HeapRegion* hr5 = g1h->region_at(8);
1299
1300 HeapWord* hr1_start = hr1->bottom();
1301 HeapWord* hr1_mid = hr1_start + HeapRegion::GrainWords/2;
1302 HeapWord* hr1_last = hr1->end() - 1;
1303
1304 HeapWord* hr2_start = hr2->bottom();
1305 HeapWord* hr2_mid = hr2_start + HeapRegion::GrainWords/2;
1306 HeapWord* hr2_last = hr2->end() - 1;
1307
1308 HeapWord* hr3_start = hr3->bottom();
1309 HeapWord* hr3_mid = hr3_start + HeapRegion::GrainWords/2;
1310 HeapWord* hr3_last = hr3->end() - 1;
1311
1312 HeapRegionRemSet* hrrs = hr0->rem_set();
1313
1314 // Make three references from region 0x101...
1315 hrrs->add_reference((OopOrNarrowOopStar)hr1_start);
1316 hrrs->add_reference((OopOrNarrowOopStar)hr1_mid);
1317 hrrs->add_reference((OopOrNarrowOopStar)hr1_last);
1318
1319 hrrs->add_reference((OopOrNarrowOopStar)hr2_start);
1320 hrrs->add_reference((OopOrNarrowOopStar)hr2_mid);
1321 hrrs->add_reference((OopOrNarrowOopStar)hr2_last);
1322
1323 hrrs->add_reference((OopOrNarrowOopStar)hr3_start);
1324 hrrs->add_reference((OopOrNarrowOopStar)hr3_mid);
1325 hrrs->add_reference((OopOrNarrowOopStar)hr3_last);
1326
1327 // Now cause a coarsening.
1328 hrrs->add_reference((OopOrNarrowOopStar)hr4->bottom());
1329 hrrs->add_reference((OopOrNarrowOopStar)hr5->bottom());
1330
1331 // Now, does iteration yield these three?
1332 HeapRegionRemSetIterator iter(hrrs);
1333 size_t sum = 0;
1334 size_t card_index;
1335 while (iter.has_next(card_index)) {
1336 HeapWord* card_start =
1337 G1CollectedHeap::heap()->bot_shared()->address_for_index(card_index);
1338 gclog_or_tty->print_cr(" Card " PTR_FORMAT ".", card_start);
1339 sum++;
1340 }
1341 guarantee(sum == 11 - 3 + 2048, "Failure");
1342 guarantee(sum == hrrs->occupied(), "Failure");
1343 }
1344 #endif