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src/share/vm/gc_implementation/g1/heapRegionRemSet.cpp@58054a18d735
src/share/vm/gc_implementation/g1/heapRegionRemSet.cpp
Fri, 06 Feb 2009 01:38:50 +0300
- author
- apetrusenko
- date
- Fri, 06 Feb 2009 01:38:50 +0300
- changeset 980
- 58054a18d735
- parent 924
- 2494ab195856
- child 1014
- 0fbdb4381b99
- child 1080
- c3a720eefe82
- permissions
- -rw-r--r--
6484959: G1: introduce survivor spaces
6797754: G1: combined bugfix
Summary: Implemented a policy to control G1 survivor space parameters.
Reviewed-by: tonyp, iveresov
1 /*
2 * Copyright 2001-2007 Sun Microsystems, Inc. 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
20 * CA 95054 USA or visit www.sun.com if you need additional information or
21 * have any questions.
22 *
23 */
25 #include "incls/_precompiled.incl"
26 #include "incls/_heapRegionRemSet.cpp.incl"
28 #define HRRS_VERBOSE 0
30 #define PRT_COUNT_OCCUPIED 1
32 // OtherRegionsTable
34 class PerRegionTable: public CHeapObj {
35 friend class OtherRegionsTable;
36 friend class HeapRegionRemSetIterator;
38 HeapRegion* _hr;
39 BitMap _bm;
40 #if PRT_COUNT_OCCUPIED
41 jint _occupied;
42 #endif
43 PerRegionTable* _next_free;
45 PerRegionTable* next_free() { return _next_free; }
46 void set_next_free(PerRegionTable* prt) { _next_free = prt; }
49 static PerRegionTable* _free_list;
51 #ifdef _MSC_VER
52 // For some reason even though the classes are marked as friend they are unable
53 // to access CardsPerRegion when private/protected. Only the windows c++ compiler
54 // says this Sun CC and linux gcc don't have a problem with access when private
56 public:
58 #endif // _MSC_VER
60 enum SomePrivateConstants {
61 CardsPerRegion = HeapRegion::GrainBytes >> CardTableModRefBS::card_shift
62 };
64 protected:
65 // We need access in order to union things into the base table.
66 BitMap* bm() { return &_bm; }
68 #if PRT_COUNT_OCCUPIED
69 void recount_occupied() {
70 _occupied = (jint) bm()->count_one_bits();
71 }
72 #endif
74 PerRegionTable(HeapRegion* hr) :
75 _hr(hr),
76 #if PRT_COUNT_OCCUPIED
77 _occupied(0),
78 #endif
79 _bm(CardsPerRegion, false /* in-resource-area */)
80 {}
82 static void free(PerRegionTable* prt) {
83 while (true) {
84 PerRegionTable* fl = _free_list;
85 prt->set_next_free(fl);
86 PerRegionTable* res =
87 (PerRegionTable*)
88 Atomic::cmpxchg_ptr(prt, &_free_list, fl);
89 if (res == fl) return;
90 }
91 ShouldNotReachHere();
92 }
94 static PerRegionTable* alloc(HeapRegion* hr) {
95 PerRegionTable* fl = _free_list;
96 while (fl != NULL) {
97 PerRegionTable* nxt = fl->next_free();
98 PerRegionTable* res =
99 (PerRegionTable*)
100 Atomic::cmpxchg_ptr(nxt, &_free_list, fl);
101 if (res == fl) {
102 fl->init(hr);
103 return fl;
104 } else {
105 fl = _free_list;
106 }
107 }
108 assert(fl == NULL, "Loop condition.");
109 return new PerRegionTable(hr);
110 }
112 void add_card_work(short from_card, bool par) {
113 if (!_bm.at(from_card)) {
114 if (par) {
115 if (_bm.par_at_put(from_card, 1)) {
116 #if PRT_COUNT_OCCUPIED
117 Atomic::inc(&_occupied);
118 #endif
119 }
120 } else {
121 _bm.at_put(from_card, 1);
122 #if PRT_COUNT_OCCUPIED
123 _occupied++;
124 #endif
125 }
126 }
127 }
129 void add_reference_work(oop* from, bool par) {
130 // Must make this robust in case "from" is not in "_hr", because of
131 // concurrency.
133 #if HRRS_VERBOSE
134 gclog_or_tty->print_cr(" PRT::Add_reference_work(" PTR_FORMAT "->" PTR_FORMAT").",
135 from, *from);
136 #endif
138 HeapRegion* loc_hr = hr();
139 // If the test below fails, then this table was reused concurrently
140 // with this operation. This is OK, since the old table was coarsened,
141 // and adding a bit to the new table is never incorrect.
142 if (loc_hr->is_in_reserved(from)) {
143 size_t hw_offset = pointer_delta((HeapWord*)from, loc_hr->bottom());
144 size_t from_card =
145 hw_offset >>
146 (CardTableModRefBS::card_shift - LogHeapWordSize);
148 add_card_work((short) from_card, par);
149 }
150 }
152 public:
154 HeapRegion* hr() const { return _hr; }
156 #if PRT_COUNT_OCCUPIED
157 jint occupied() const {
158 // Overkill, but if we ever need it...
159 // guarantee(_occupied == _bm.count_one_bits(), "Check");
160 return _occupied;
161 }
162 #else
163 jint occupied() const {
164 return _bm.count_one_bits();
165 }
166 #endif
168 void init(HeapRegion* hr) {
169 _hr = hr;
170 #if PRT_COUNT_OCCUPIED
171 _occupied = 0;
172 #endif
173 _bm.clear();
174 }
176 void add_reference(oop* from) {
177 add_reference_work(from, /*parallel*/ true);
178 }
180 void seq_add_reference(oop* from) {
181 add_reference_work(from, /*parallel*/ false);
182 }
184 void scrub(CardTableModRefBS* ctbs, BitMap* card_bm) {
185 HeapWord* hr_bot = hr()->bottom();
186 size_t hr_first_card_index = ctbs->index_for(hr_bot);
187 bm()->set_intersection_at_offset(*card_bm, hr_first_card_index);
188 #if PRT_COUNT_OCCUPIED
189 recount_occupied();
190 #endif
191 }
193 void add_card(short from_card_index) {
194 add_card_work(from_card_index, /*parallel*/ true);
195 }
197 void seq_add_card(short from_card_index) {
198 add_card_work(from_card_index, /*parallel*/ false);
199 }
201 // (Destructively) union the bitmap of the current table into the given
202 // bitmap (which is assumed to be of the same size.)
203 void union_bitmap_into(BitMap* bm) {
204 bm->set_union(_bm);
205 }
207 // Mem size in bytes.
208 size_t mem_size() const {
209 return sizeof(this) + _bm.size_in_words() * HeapWordSize;
210 }
212 static size_t fl_mem_size() {
213 PerRegionTable* cur = _free_list;
214 size_t res = 0;
215 while (cur != NULL) {
216 res += sizeof(PerRegionTable);
217 cur = cur->next_free();
218 }
219 return res;
220 }
222 // Requires "from" to be in "hr()".
223 bool contains_reference(oop* from) const {
224 assert(hr()->is_in_reserved(from), "Precondition.");
225 size_t card_ind = pointer_delta(from, hr()->bottom(),
226 CardTableModRefBS::card_size);
227 return _bm.at(card_ind);
228 }
229 };
231 PerRegionTable* PerRegionTable::_free_list = NULL;
234 #define COUNT_PAR_EXPANDS 0
236 #if COUNT_PAR_EXPANDS
237 static jint n_par_expands = 0;
238 static jint n_par_contracts = 0;
239 static jint par_expand_list_len = 0;
240 static jint max_par_expand_list_len = 0;
242 static void print_par_expand() {
243 Atomic::inc(&n_par_expands);
244 Atomic::inc(&par_expand_list_len);
245 if (par_expand_list_len > max_par_expand_list_len) {
246 max_par_expand_list_len = par_expand_list_len;
247 }
248 if ((n_par_expands % 10) == 0) {
249 gclog_or_tty->print_cr("\n\n%d par expands: %d contracts, "
250 "len = %d, max_len = %d\n.",
251 n_par_expands, n_par_contracts, par_expand_list_len,
252 max_par_expand_list_len);
253 }
254 }
255 #endif
257 class PosParPRT: public PerRegionTable {
258 PerRegionTable** _par_tables;
260 enum SomePrivateConstants {
261 ReserveParTableExpansion = 1
262 };
264 void par_expand() {
265 int n = HeapRegionRemSet::num_par_rem_sets()-1;
266 if (n <= 0) return;
267 if (_par_tables == NULL) {
268 PerRegionTable* res =
269 (PerRegionTable*)
270 Atomic::cmpxchg_ptr((PerRegionTable*)ReserveParTableExpansion,
271 &_par_tables, NULL);
272 if (res != NULL) return;
273 // Otherwise, we reserved the right to do the expansion.
275 PerRegionTable** ptables = NEW_C_HEAP_ARRAY(PerRegionTable*, n);
276 for (int i = 0; i < n; i++) {
277 PerRegionTable* ptable = PerRegionTable::alloc(hr());
278 ptables[i] = ptable;
279 }
280 // Here we do not need an atomic.
281 _par_tables = ptables;
282 #if COUNT_PAR_EXPANDS
283 print_par_expand();
284 #endif
285 // We must put this table on the expanded list.
286 PosParPRT* exp_head = _par_expanded_list;
287 while (true) {
288 set_next_par_expanded(exp_head);
289 PosParPRT* res =
290 (PosParPRT*)
291 Atomic::cmpxchg_ptr(this, &_par_expanded_list, exp_head);
292 if (res == exp_head) return;
293 // Otherwise.
294 exp_head = res;
295 }
296 ShouldNotReachHere();
297 }
298 }
300 void par_contract() {
301 assert(_par_tables != NULL, "Precondition.");
302 int n = HeapRegionRemSet::num_par_rem_sets()-1;
303 for (int i = 0; i < n; i++) {
304 _par_tables[i]->union_bitmap_into(bm());
305 PerRegionTable::free(_par_tables[i]);
306 _par_tables[i] = NULL;
307 }
308 #if PRT_COUNT_OCCUPIED
309 // We must recount the "occupied."
310 recount_occupied();
311 #endif
312 FREE_C_HEAP_ARRAY(PerRegionTable*, _par_tables);
313 _par_tables = NULL;
314 #if COUNT_PAR_EXPANDS
315 Atomic::inc(&n_par_contracts);
316 Atomic::dec(&par_expand_list_len);
317 #endif
318 }
320 static PerRegionTable** _par_table_fl;
322 PosParPRT* _next;
324 static PosParPRT* _free_list;
326 PerRegionTable** par_tables() const {
327 assert(uintptr_t(NULL) == 0, "Assumption.");
328 if (uintptr_t(_par_tables) <= ReserveParTableExpansion)
329 return NULL;
330 else
331 return _par_tables;
332 }
334 PosParPRT* _next_par_expanded;
335 PosParPRT* next_par_expanded() { return _next_par_expanded; }
336 void set_next_par_expanded(PosParPRT* ppprt) { _next_par_expanded = ppprt; }
337 static PosParPRT* _par_expanded_list;
339 public:
341 PosParPRT(HeapRegion* hr) : PerRegionTable(hr), _par_tables(NULL) {}
343 jint occupied() const {
344 jint res = PerRegionTable::occupied();
345 if (par_tables() != NULL) {
346 for (int i = 0; i < HeapRegionRemSet::num_par_rem_sets()-1; i++) {
347 res += par_tables()[i]->occupied();
348 }
349 }
350 return res;
351 }
353 void init(HeapRegion* hr) {
354 PerRegionTable::init(hr);
355 _next = NULL;
356 if (par_tables() != NULL) {
357 for (int i = 0; i < HeapRegionRemSet::num_par_rem_sets()-1; i++) {
358 par_tables()[i]->init(hr);
359 }
360 }
361 }
363 static void free(PosParPRT* prt) {
364 while (true) {
365 PosParPRT* fl = _free_list;
366 prt->set_next(fl);
367 PosParPRT* res =
368 (PosParPRT*)
369 Atomic::cmpxchg_ptr(prt, &_free_list, fl);
370 if (res == fl) return;
371 }
372 ShouldNotReachHere();
373 }
375 static PosParPRT* alloc(HeapRegion* hr) {
376 PosParPRT* fl = _free_list;
377 while (fl != NULL) {
378 PosParPRT* nxt = fl->next();
379 PosParPRT* res =
380 (PosParPRT*)
381 Atomic::cmpxchg_ptr(nxt, &_free_list, fl);
382 if (res == fl) {
383 fl->init(hr);
384 return fl;
385 } else {
386 fl = _free_list;
387 }
388 }
389 assert(fl == NULL, "Loop condition.");
390 return new PosParPRT(hr);
391 }
393 PosParPRT* next() const { return _next; }
394 void set_next(PosParPRT* nxt) { _next = nxt; }
395 PosParPRT** next_addr() { return &_next; }
397 void add_reference(oop* from, int tid) {
398 // Expand if necessary.
399 PerRegionTable** pt = par_tables();
400 if (par_tables() == NULL && tid > 0 && hr()->is_gc_alloc_region()) {
401 par_expand();
402 pt = par_tables();
403 }
404 if (pt != NULL) {
405 // We always have to assume that mods to table 0 are in parallel,
406 // because of the claiming scheme in parallel expansion. A thread
407 // with tid != 0 that finds the table to be NULL, but doesn't succeed
408 // in claiming the right of expanding it, will end up in the else
409 // clause of the above if test. That thread could be delayed, and a
410 // thread 0 add reference could see the table expanded, and come
411 // here. Both threads would be adding in parallel. But we get to
412 // not use atomics for tids > 0.
413 if (tid == 0) {
414 PerRegionTable::add_reference(from);
415 } else {
416 pt[tid-1]->seq_add_reference(from);
417 }
418 } else {
419 // Not expanded -- add to the base table.
420 PerRegionTable::add_reference(from);
421 }
422 }
424 void scrub(CardTableModRefBS* ctbs, BitMap* card_bm) {
425 assert(_par_tables == NULL, "Precondition");
426 PerRegionTable::scrub(ctbs, card_bm);
427 }
429 size_t mem_size() const {
430 size_t res =
431 PerRegionTable::mem_size() + sizeof(this) - sizeof(PerRegionTable);
432 if (_par_tables != NULL) {
433 for (int i = 0; i < HeapRegionRemSet::num_par_rem_sets()-1; i++) {
434 res += _par_tables[i]->mem_size();
435 }
436 }
437 return res;
438 }
440 static size_t fl_mem_size() {
441 PosParPRT* cur = _free_list;
442 size_t res = 0;
443 while (cur != NULL) {
444 res += sizeof(PosParPRT);
445 cur = cur->next();
446 }
447 return res;
448 }
450 bool contains_reference(oop* from) const {
451 if (PerRegionTable::contains_reference(from)) return true;
452 if (_par_tables != NULL) {
453 for (int i = 0; i < HeapRegionRemSet::num_par_rem_sets()-1; i++) {
454 if (_par_tables[i]->contains_reference(from)) return true;
455 }
456 }
457 return false;
458 }
460 static void par_contract_all();
462 };
464 void PosParPRT::par_contract_all() {
465 PosParPRT* hd = _par_expanded_list;
466 while (hd != NULL) {
467 PosParPRT* nxt = hd->next_par_expanded();
468 PosParPRT* res =
469 (PosParPRT*)
470 Atomic::cmpxchg_ptr(nxt, &_par_expanded_list, hd);
471 if (res == hd) {
472 // We claimed the right to contract this table.
473 hd->set_next_par_expanded(NULL);
474 hd->par_contract();
475 hd = _par_expanded_list;
476 } else {
477 hd = res;
478 }
479 }
480 }
482 PosParPRT* PosParPRT::_free_list = NULL;
483 PosParPRT* PosParPRT::_par_expanded_list = NULL;
485 jint OtherRegionsTable::_cache_probes = 0;
486 jint OtherRegionsTable::_cache_hits = 0;
488 size_t OtherRegionsTable::_max_fine_entries = 0;
489 size_t OtherRegionsTable::_mod_max_fine_entries_mask = 0;
490 #if SAMPLE_FOR_EVICTION
491 size_t OtherRegionsTable::_fine_eviction_stride = 0;
492 size_t OtherRegionsTable::_fine_eviction_sample_size = 0;
493 #endif
495 OtherRegionsTable::OtherRegionsTable(HeapRegion* hr) :
496 _g1h(G1CollectedHeap::heap()),
497 _m(Mutex::leaf, "An OtherRegionsTable lock", true),
498 _hr(hr),
499 _coarse_map(G1CollectedHeap::heap()->max_regions(),
500 false /* in-resource-area */),
501 _fine_grain_regions(NULL),
502 _n_fine_entries(0), _n_coarse_entries(0),
503 #if SAMPLE_FOR_EVICTION
504 _fine_eviction_start(0),
505 #endif
506 _sparse_table(hr)
507 {
508 typedef PosParPRT* PosParPRTPtr;
509 if (_max_fine_entries == 0) {
510 assert(_mod_max_fine_entries_mask == 0, "Both or none.");
511 _max_fine_entries = (1 << G1LogRSRegionEntries);
512 _mod_max_fine_entries_mask = _max_fine_entries - 1;
513 #if SAMPLE_FOR_EVICTION
514 assert(_fine_eviction_sample_size == 0
515 && _fine_eviction_stride == 0, "All init at same time.");
516 _fine_eviction_sample_size = MAX2((size_t)4, (size_t)G1LogRSRegionEntries);
517 _fine_eviction_stride = _max_fine_entries / _fine_eviction_sample_size;
518 #endif
519 }
520 _fine_grain_regions = new PosParPRTPtr[_max_fine_entries];
521 if (_fine_grain_regions == NULL)
522 vm_exit_out_of_memory(sizeof(void*)*_max_fine_entries,
523 "Failed to allocate _fine_grain_entries.");
524 for (size_t i = 0; i < _max_fine_entries; i++) {
525 _fine_grain_regions[i] = NULL;
526 }
527 }
529 int** OtherRegionsTable::_from_card_cache = NULL;
530 size_t OtherRegionsTable::_from_card_cache_max_regions = 0;
531 size_t OtherRegionsTable::_from_card_cache_mem_size = 0;
533 void OtherRegionsTable::init_from_card_cache(size_t max_regions) {
534 _from_card_cache_max_regions = max_regions;
536 int n_par_rs = HeapRegionRemSet::num_par_rem_sets();
537 _from_card_cache = NEW_C_HEAP_ARRAY(int*, n_par_rs);
538 for (int i = 0; i < n_par_rs; i++) {
539 _from_card_cache[i] = NEW_C_HEAP_ARRAY(int, max_regions);
540 for (size_t j = 0; j < max_regions; j++) {
541 _from_card_cache[i][j] = -1; // An invalid value.
542 }
543 }
544 _from_card_cache_mem_size = n_par_rs * max_regions * sizeof(int);
545 }
547 void OtherRegionsTable::shrink_from_card_cache(size_t new_n_regs) {
548 for (int i = 0; i < HeapRegionRemSet::num_par_rem_sets(); i++) {
549 assert(new_n_regs <= _from_card_cache_max_regions, "Must be within max.");
550 for (size_t j = new_n_regs; j < _from_card_cache_max_regions; j++) {
551 _from_card_cache[i][j] = -1; // An invalid value.
552 }
553 }
554 }
556 #ifndef PRODUCT
557 void OtherRegionsTable::print_from_card_cache() {
558 for (int i = 0; i < HeapRegionRemSet::num_par_rem_sets(); i++) {
559 for (size_t j = 0; j < _from_card_cache_max_regions; j++) {
560 gclog_or_tty->print_cr("_from_card_cache[%d][%d] = %d.",
561 i, j, _from_card_cache[i][j]);
562 }
563 }
564 }
565 #endif
567 void OtherRegionsTable::add_reference(oop* from, int tid) {
568 size_t cur_hrs_ind = hr()->hrs_index();
570 #if HRRS_VERBOSE
571 gclog_or_tty->print_cr("ORT::add_reference_work(" PTR_FORMAT "->" PTR_FORMAT ").",
572 from, *from);
573 #endif
575 int from_card = (int)(uintptr_t(from) >> CardTableModRefBS::card_shift);
577 #if HRRS_VERBOSE
578 gclog_or_tty->print_cr("Table for [" PTR_FORMAT "...): card %d (cache = %d)",
579 hr()->bottom(), from_card,
580 _from_card_cache[tid][cur_hrs_ind]);
581 #endif
583 #define COUNT_CACHE 0
584 #if COUNT_CACHE
585 jint p = Atomic::add(1, &_cache_probes);
586 if ((p % 10000) == 0) {
587 jint hits = _cache_hits;
588 gclog_or_tty->print_cr("%d/%d = %5.2f%% RS cache hits.",
589 _cache_hits, p, 100.0* (float)hits/(float)p);
590 }
591 #endif
592 if (from_card == _from_card_cache[tid][cur_hrs_ind]) {
593 #if HRRS_VERBOSE
594 gclog_or_tty->print_cr(" from-card cache hit.");
595 #endif
596 #if COUNT_CACHE
597 Atomic::inc(&_cache_hits);
598 #endif
599 assert(contains_reference(from), "We just added it!");
600 return;
601 } else {
602 _from_card_cache[tid][cur_hrs_ind] = from_card;
603 }
605 // Note that this may be a continued H region.
606 HeapRegion* from_hr = _g1h->heap_region_containing_raw(from);
607 size_t from_hrs_ind = (size_t)from_hr->hrs_index();
609 // If the region is already coarsened, return.
610 if (_coarse_map.at(from_hrs_ind)) {
611 #if HRRS_VERBOSE
612 gclog_or_tty->print_cr(" coarse map hit.");
613 #endif
614 assert(contains_reference(from), "We just added it!");
615 return;
616 }
618 // Otherwise find a per-region table to add it to.
619 size_t ind = from_hrs_ind & _mod_max_fine_entries_mask;
620 PosParPRT* prt = find_region_table(ind, from_hr);
621 if (prt == NULL) {
622 MutexLockerEx x(&_m, Mutex::_no_safepoint_check_flag);
623 // Confirm that it's really not there...
624 prt = find_region_table(ind, from_hr);
625 if (prt == NULL) {
627 uintptr_t from_hr_bot_card_index =
628 uintptr_t(from_hr->bottom())
629 >> CardTableModRefBS::card_shift;
630 int card_index = from_card - from_hr_bot_card_index;
631 assert(0 <= card_index && card_index < PosParPRT::CardsPerRegion,
632 "Must be in range.");
633 if (G1HRRSUseSparseTable &&
634 _sparse_table.add_card((short) from_hrs_ind, card_index)) {
635 if (G1RecordHRRSOops) {
636 HeapRegionRemSet::record(hr(), from);
637 #if HRRS_VERBOSE
638 gclog_or_tty->print(" Added card " PTR_FORMAT " to region "
639 "[" PTR_FORMAT "...) for ref " PTR_FORMAT ".\n",
640 align_size_down(uintptr_t(from),
641 CardTableModRefBS::card_size),
642 hr()->bottom(), from);
643 #endif
644 }
645 #if HRRS_VERBOSE
646 gclog_or_tty->print_cr(" added card to sparse table.");
647 #endif
648 assert(contains_reference_locked(from), "We just added it!");
649 return;
650 } else {
651 #if HRRS_VERBOSE
652 gclog_or_tty->print_cr(" [tid %d] sparse table entry "
653 "overflow(f: %d, t: %d)",
654 tid, from_hrs_ind, cur_hrs_ind);
655 #endif
656 }
658 // Otherwise, transfer from sparse to fine-grain.
659 short cards[SparsePRTEntry::CardsPerEntry];
660 if (G1HRRSUseSparseTable) {
661 bool res = _sparse_table.get_cards((short) from_hrs_ind, &cards[0]);
662 assert(res, "There should have been an entry");
663 }
665 if (_n_fine_entries == _max_fine_entries) {
666 prt = delete_region_table();
667 } else {
668 prt = PosParPRT::alloc(from_hr);
669 }
670 prt->init(from_hr);
671 // Record the outgoing pointer in the from_region's outgoing bitmap.
672 from_hr->rem_set()->add_outgoing_reference(hr());
674 PosParPRT* first_prt = _fine_grain_regions[ind];
675 prt->set_next(first_prt); // XXX Maybe move to init?
676 _fine_grain_regions[ind] = prt;
677 _n_fine_entries++;
679 // Add in the cards from the sparse table.
680 if (G1HRRSUseSparseTable) {
681 for (int i = 0; i < SparsePRTEntry::CardsPerEntry; i++) {
682 short c = cards[i];
683 if (c != SparsePRTEntry::NullEntry) {
684 prt->add_card(c);
685 }
686 }
687 // Now we can delete the sparse entry.
688 bool res = _sparse_table.delete_entry((short) from_hrs_ind);
689 assert(res, "It should have been there.");
690 }
691 }
692 assert(prt != NULL && prt->hr() == from_hr, "consequence");
693 }
694 // Note that we can't assert "prt->hr() == from_hr", because of the
695 // possibility of concurrent reuse. But see head comment of
696 // OtherRegionsTable for why this is OK.
697 assert(prt != NULL, "Inv");
699 prt->add_reference(from, tid);
700 if (G1RecordHRRSOops) {
701 HeapRegionRemSet::record(hr(), from);
702 #if HRRS_VERBOSE
703 gclog_or_tty->print("Added card " PTR_FORMAT " to region "
704 "[" PTR_FORMAT "...) for ref " PTR_FORMAT ".\n",
705 align_size_down(uintptr_t(from),
706 CardTableModRefBS::card_size),
707 hr()->bottom(), from);
708 #endif
709 }
710 assert(contains_reference(from), "We just added it!");
711 }
713 PosParPRT*
714 OtherRegionsTable::find_region_table(size_t ind, HeapRegion* hr) const {
715 assert(0 <= ind && ind < _max_fine_entries, "Preconditions.");
716 PosParPRT* prt = _fine_grain_regions[ind];
717 while (prt != NULL && prt->hr() != hr) {
718 prt = prt->next();
719 }
720 // Loop postcondition is the method postcondition.
721 return prt;
722 }
725 #define DRT_CENSUS 0
727 #if DRT_CENSUS
728 static const int HistoSize = 6;
729 static int global_histo[HistoSize] = { 0, 0, 0, 0, 0, 0 };
730 static int coarsenings = 0;
731 static int occ_sum = 0;
732 #endif
734 jint OtherRegionsTable::_n_coarsenings = 0;
736 PosParPRT* OtherRegionsTable::delete_region_table() {
737 #if DRT_CENSUS
738 int histo[HistoSize] = { 0, 0, 0, 0, 0, 0 };
739 const int histo_limits[] = { 1, 4, 16, 64, 256, 2048 };
740 #endif
742 assert(_m.owned_by_self(), "Precondition");
743 assert(_n_fine_entries == _max_fine_entries, "Precondition");
744 PosParPRT* max = NULL;
745 jint max_occ = 0;
746 PosParPRT** max_prev;
747 size_t max_ind;
749 #if SAMPLE_FOR_EVICTION
750 size_t i = _fine_eviction_start;
751 for (size_t k = 0; k < _fine_eviction_sample_size; k++) {
752 size_t ii = i;
753 // Make sure we get a non-NULL sample.
754 while (_fine_grain_regions[ii] == NULL) {
755 ii++;
756 if (ii == _max_fine_entries) ii = 0;
757 guarantee(ii != i, "We must find one.");
758 }
759 PosParPRT** prev = &_fine_grain_regions[ii];
760 PosParPRT* cur = *prev;
761 while (cur != NULL) {
762 jint cur_occ = cur->occupied();
763 if (max == NULL || cur_occ > max_occ) {
764 max = cur;
765 max_prev = prev;
766 max_ind = i;
767 max_occ = cur_occ;
768 }
769 prev = cur->next_addr();
770 cur = cur->next();
771 }
772 i = i + _fine_eviction_stride;
773 if (i >= _n_fine_entries) i = i - _n_fine_entries;
774 }
775 _fine_eviction_start++;
776 if (_fine_eviction_start >= _n_fine_entries)
777 _fine_eviction_start -= _n_fine_entries;
778 #else
779 for (int i = 0; i < _max_fine_entries; i++) {
780 PosParPRT** prev = &_fine_grain_regions[i];
781 PosParPRT* cur = *prev;
782 while (cur != NULL) {
783 jint cur_occ = cur->occupied();
784 #if DRT_CENSUS
785 for (int k = 0; k < HistoSize; k++) {
786 if (cur_occ <= histo_limits[k]) {
787 histo[k]++; global_histo[k]++; break;
788 }
789 }
790 #endif
791 if (max == NULL || cur_occ > max_occ) {
792 max = cur;
793 max_prev = prev;
794 max_ind = i;
795 max_occ = cur_occ;
796 }
797 prev = cur->next_addr();
798 cur = cur->next();
799 }
800 }
801 #endif
802 // XXX
803 guarantee(max != NULL, "Since _n_fine_entries > 0");
804 #if DRT_CENSUS
805 gclog_or_tty->print_cr("In a coarsening: histo of occs:");
806 for (int k = 0; k < HistoSize; k++) {
807 gclog_or_tty->print_cr(" <= %4d: %5d.", histo_limits[k], histo[k]);
808 }
809 coarsenings++;
810 occ_sum += max_occ;
811 if ((coarsenings % 100) == 0) {
812 gclog_or_tty->print_cr("\ncoarsenings = %d; global summary:", coarsenings);
813 for (int k = 0; k < HistoSize; k++) {
814 gclog_or_tty->print_cr(" <= %4d: %5d.", histo_limits[k], global_histo[k]);
815 }
816 gclog_or_tty->print_cr("Avg occ of deleted region = %6.2f.",
817 (float)occ_sum/(float)coarsenings);
818 }
819 #endif
821 // Set the corresponding coarse bit.
822 int max_hrs_index = max->hr()->hrs_index();
823 if (!_coarse_map.at(max_hrs_index)) {
824 _coarse_map.at_put(max_hrs_index, true);
825 _n_coarse_entries++;
826 #if 0
827 gclog_or_tty->print("Coarsened entry in region [" PTR_FORMAT "...] "
828 "for region [" PTR_FORMAT "...] (%d coarse entries).\n",
829 hr()->bottom(),
830 max->hr()->bottom(),
831 _n_coarse_entries);
832 #endif
833 }
835 // Unsplice.
836 *max_prev = max->next();
837 Atomic::inc(&_n_coarsenings);
838 _n_fine_entries--;
839 return max;
840 }
843 // At present, this must be called stop-world single-threaded.
844 void OtherRegionsTable::scrub(CardTableModRefBS* ctbs,
845 BitMap* region_bm, BitMap* card_bm) {
846 // First eliminated garbage regions from the coarse map.
847 if (G1RSScrubVerbose)
848 gclog_or_tty->print_cr("Scrubbing region %d:", hr()->hrs_index());
850 assert(_coarse_map.size() == region_bm->size(), "Precondition");
851 if (G1RSScrubVerbose)
852 gclog_or_tty->print(" Coarse map: before = %d...", _n_coarse_entries);
853 _coarse_map.set_intersection(*region_bm);
854 _n_coarse_entries = _coarse_map.count_one_bits();
855 if (G1RSScrubVerbose)
856 gclog_or_tty->print_cr(" after = %d.", _n_coarse_entries);
858 // Now do the fine-grained maps.
859 for (size_t i = 0; i < _max_fine_entries; i++) {
860 PosParPRT* cur = _fine_grain_regions[i];
861 PosParPRT** prev = &_fine_grain_regions[i];
862 while (cur != NULL) {
863 PosParPRT* nxt = cur->next();
864 // If the entire region is dead, eliminate.
865 if (G1RSScrubVerbose)
866 gclog_or_tty->print_cr(" For other region %d:", cur->hr()->hrs_index());
867 if (!region_bm->at(cur->hr()->hrs_index())) {
868 *prev = nxt;
869 cur->set_next(NULL);
870 _n_fine_entries--;
871 if (G1RSScrubVerbose)
872 gclog_or_tty->print_cr(" deleted via region map.");
873 PosParPRT::free(cur);
874 } else {
875 // Do fine-grain elimination.
876 if (G1RSScrubVerbose)
877 gclog_or_tty->print(" occ: before = %4d.", cur->occupied());
878 cur->scrub(ctbs, card_bm);
879 if (G1RSScrubVerbose)
880 gclog_or_tty->print_cr(" after = %4d.", cur->occupied());
881 // Did that empty the table completely?
882 if (cur->occupied() == 0) {
883 *prev = nxt;
884 cur->set_next(NULL);
885 _n_fine_entries--;
886 PosParPRT::free(cur);
887 } else {
888 prev = cur->next_addr();
889 }
890 }
891 cur = nxt;
892 }
893 }
894 // Since we may have deleted a from_card_cache entry from the RS, clear
895 // the FCC.
896 clear_fcc();
897 }
900 size_t OtherRegionsTable::occupied() const {
901 // Cast away const in this case.
902 MutexLockerEx x((Mutex*)&_m, Mutex::_no_safepoint_check_flag);
903 size_t sum = occ_fine();
904 sum += occ_sparse();
905 sum += occ_coarse();
906 return sum;
907 }
909 size_t OtherRegionsTable::occ_fine() const {
910 size_t sum = 0;
911 for (size_t i = 0; i < _max_fine_entries; i++) {
912 PosParPRT* cur = _fine_grain_regions[i];
913 while (cur != NULL) {
914 sum += cur->occupied();
915 cur = cur->next();
916 }
917 }
918 return sum;
919 }
921 size_t OtherRegionsTable::occ_coarse() const {
922 return (_n_coarse_entries * PosParPRT::CardsPerRegion);
923 }
925 size_t OtherRegionsTable::occ_sparse() const {
926 return _sparse_table.occupied();
927 }
929 size_t OtherRegionsTable::mem_size() const {
930 // Cast away const in this case.
931 MutexLockerEx x((Mutex*)&_m, Mutex::_no_safepoint_check_flag);
932 size_t sum = 0;
933 for (size_t i = 0; i < _max_fine_entries; i++) {
934 PosParPRT* cur = _fine_grain_regions[i];
935 while (cur != NULL) {
936 sum += cur->mem_size();
937 cur = cur->next();
938 }
939 }
940 sum += (sizeof(PosParPRT*) * _max_fine_entries);
941 sum += (_coarse_map.size_in_words() * HeapWordSize);
942 sum += (_sparse_table.mem_size());
943 sum += sizeof(*this) - sizeof(_sparse_table); // Avoid double counting above.
944 return sum;
945 }
947 size_t OtherRegionsTable::static_mem_size() {
948 return _from_card_cache_mem_size;
949 }
951 size_t OtherRegionsTable::fl_mem_size() {
952 return PerRegionTable::fl_mem_size() + PosParPRT::fl_mem_size();
953 }
955 void OtherRegionsTable::clear_fcc() {
956 for (int i = 0; i < HeapRegionRemSet::num_par_rem_sets(); i++) {
957 _from_card_cache[i][hr()->hrs_index()] = -1;
958 }
959 }
961 void OtherRegionsTable::clear() {
962 MutexLockerEx x(&_m, Mutex::_no_safepoint_check_flag);
963 for (size_t i = 0; i < _max_fine_entries; i++) {
964 PosParPRT* cur = _fine_grain_regions[i];
965 while (cur != NULL) {
966 PosParPRT* nxt = cur->next();
967 PosParPRT::free(cur);
968 cur = nxt;
969 }
970 _fine_grain_regions[i] = NULL;
971 }
972 _sparse_table.clear();
973 _coarse_map.clear();
974 _n_fine_entries = 0;
975 _n_coarse_entries = 0;
977 clear_fcc();
978 }
980 void OtherRegionsTable::clear_incoming_entry(HeapRegion* from_hr) {
981 MutexLockerEx x(&_m, Mutex::_no_safepoint_check_flag);
982 size_t hrs_ind = (size_t)from_hr->hrs_index();
983 size_t ind = hrs_ind & _mod_max_fine_entries_mask;
984 if (del_single_region_table(ind, from_hr)) {
985 assert(!_coarse_map.at(hrs_ind), "Inv");
986 } else {
987 _coarse_map.par_at_put(hrs_ind, 0);
988 }
989 // Check to see if any of the fcc entries come from here.
990 int hr_ind = hr()->hrs_index();
991 for (int tid = 0; tid < HeapRegionRemSet::num_par_rem_sets(); tid++) {
992 int fcc_ent = _from_card_cache[tid][hr_ind];
993 if (fcc_ent != -1) {
994 HeapWord* card_addr = (HeapWord*)
995 (uintptr_t(fcc_ent) << CardTableModRefBS::card_shift);
996 if (hr()->is_in_reserved(card_addr)) {
997 // Clear the from card cache.
998 _from_card_cache[tid][hr_ind] = -1;
999 }
1000 }
1001 }
1002 }
1004 bool OtherRegionsTable::del_single_region_table(size_t ind,
1005 HeapRegion* hr) {
1006 assert(0 <= ind && ind < _max_fine_entries, "Preconditions.");
1007 PosParPRT** prev_addr = &_fine_grain_regions[ind];
1008 PosParPRT* prt = *prev_addr;
1009 while (prt != NULL && prt->hr() != hr) {
1010 prev_addr = prt->next_addr();
1011 prt = prt->next();
1012 }
1013 if (prt != NULL) {
1014 assert(prt->hr() == hr, "Loop postcondition.");
1015 *prev_addr = prt->next();
1016 PosParPRT::free(prt);
1017 _n_fine_entries--;
1018 return true;
1019 } else {
1020 return false;
1021 }
1022 }
1024 bool OtherRegionsTable::contains_reference(oop* from) const {
1025 // Cast away const in this case.
1026 MutexLockerEx x((Mutex*)&_m, Mutex::_no_safepoint_check_flag);
1027 return contains_reference_locked(from);
1028 }
1030 bool OtherRegionsTable::contains_reference_locked(oop* from) const {
1031 HeapRegion* hr = _g1h->heap_region_containing_raw(from);
1032 if (hr == NULL) return false;
1033 size_t hr_ind = hr->hrs_index();
1034 // Is this region in the coarse map?
1035 if (_coarse_map.at(hr_ind)) return true;
1037 PosParPRT* prt = find_region_table(hr_ind & _mod_max_fine_entries_mask,
1038 hr);
1039 if (prt != NULL) {
1040 return prt->contains_reference(from);
1042 } else {
1043 uintptr_t from_card =
1044 (uintptr_t(from) >> CardTableModRefBS::card_shift);
1045 uintptr_t hr_bot_card_index =
1046 uintptr_t(hr->bottom()) >> CardTableModRefBS::card_shift;
1047 assert(from_card >= hr_bot_card_index, "Inv");
1048 int card_index = from_card - hr_bot_card_index;
1049 return _sparse_table.contains_card((short)hr_ind, card_index);
1050 }
1053 }
1056 bool HeapRegionRemSet::_par_traversal = false;
1058 void HeapRegionRemSet::set_par_traversal(bool b) {
1059 assert(_par_traversal != b, "Proper alternation...");
1060 _par_traversal = b;
1061 }
1063 int HeapRegionRemSet::num_par_rem_sets() {
1064 // We always have at least two, so that a mutator thread can claim an
1065 // id and add to a rem set.
1066 return (int) MAX2(ParallelGCThreads, (size_t)2);
1067 }
1069 HeapRegionRemSet::HeapRegionRemSet(G1BlockOffsetSharedArray* bosa,
1070 HeapRegion* hr)
1071 : _bosa(bosa), _other_regions(hr),
1072 _outgoing_region_map(G1CollectedHeap::heap()->max_regions(),
1073 false /* in-resource-area */),
1074 _iter_state(Unclaimed)
1075 {}
1078 void HeapRegionRemSet::init_for_par_iteration() {
1079 _iter_state = Unclaimed;
1080 }
1082 bool HeapRegionRemSet::claim_iter() {
1083 if (_iter_state != Unclaimed) return false;
1084 jint res = Atomic::cmpxchg(Claimed, (jint*)(&_iter_state), Unclaimed);
1085 return (res == Unclaimed);
1086 }
1088 void HeapRegionRemSet::set_iter_complete() {
1089 _iter_state = Complete;
1090 }
1092 bool HeapRegionRemSet::iter_is_complete() {
1093 return _iter_state == Complete;
1094 }
1097 void HeapRegionRemSet::init_iterator(HeapRegionRemSetIterator* iter) const {
1098 iter->initialize(this);
1099 }
1101 #ifndef PRODUCT
1102 void HeapRegionRemSet::print() const {
1103 HeapRegionRemSetIterator iter;
1104 init_iterator(&iter);
1105 size_t card_index;
1106 while (iter.has_next(card_index)) {
1107 HeapWord* card_start =
1108 G1CollectedHeap::heap()->bot_shared()->address_for_index(card_index);
1109 gclog_or_tty->print_cr(" Card " PTR_FORMAT ".", card_start);
1110 }
1111 // XXX
1112 if (iter.n_yielded() != occupied()) {
1113 gclog_or_tty->print_cr("Yielded disagrees with occupied:");
1114 gclog_or_tty->print_cr(" %6d yielded (%6d coarse, %6d fine).",
1115 iter.n_yielded(),
1116 iter.n_yielded_coarse(), iter.n_yielded_fine());
1117 gclog_or_tty->print_cr(" %6d occ (%6d coarse, %6d fine).",
1118 occupied(), occ_coarse(), occ_fine());
1119 }
1120 guarantee(iter.n_yielded() == occupied(),
1121 "We should have yielded all the represented cards.");
1122 }
1123 #endif
1125 void HeapRegionRemSet::cleanup() {
1126 SparsePRT::cleanup_all();
1127 }
1129 void HeapRegionRemSet::par_cleanup() {
1130 PosParPRT::par_contract_all();
1131 }
1133 void HeapRegionRemSet::add_outgoing_reference(HeapRegion* to_hr) {
1134 _outgoing_region_map.par_at_put(to_hr->hrs_index(), 1);
1135 }
1137 void HeapRegionRemSet::clear() {
1138 clear_outgoing_entries();
1139 _outgoing_region_map.clear();
1140 _other_regions.clear();
1141 assert(occupied() == 0, "Should be clear.");
1142 }
1144 void HeapRegionRemSet::clear_outgoing_entries() {
1145 G1CollectedHeap* g1h = G1CollectedHeap::heap();
1146 size_t i = _outgoing_region_map.get_next_one_offset(0);
1147 while (i < _outgoing_region_map.size()) {
1148 HeapRegion* to_region = g1h->region_at(i);
1149 if (!to_region->in_collection_set()) {
1150 to_region->rem_set()->clear_incoming_entry(hr());
1151 }
1152 i = _outgoing_region_map.get_next_one_offset(i+1);
1153 }
1154 }
1157 void HeapRegionRemSet::scrub(CardTableModRefBS* ctbs,
1158 BitMap* region_bm, BitMap* card_bm) {
1159 _other_regions.scrub(ctbs, region_bm, card_bm);
1160 }
1162 //-------------------- Iteration --------------------
1164 HeapRegionRemSetIterator::
1165 HeapRegionRemSetIterator() :
1166 _hrrs(NULL),
1167 _g1h(G1CollectedHeap::heap()),
1168 _bosa(NULL),
1169 _sparse_iter(size_t(G1CollectedHeap::heap()->reserved_region().start())
1170 >> CardTableModRefBS::card_shift)
1171 {}
1173 void HeapRegionRemSetIterator::initialize(const HeapRegionRemSet* hrrs) {
1174 _hrrs = hrrs;
1175 _coarse_map = &_hrrs->_other_regions._coarse_map;
1176 _fine_grain_regions = _hrrs->_other_regions._fine_grain_regions;
1177 _bosa = _hrrs->bosa();
1179 _is = Sparse;
1180 // Set these values so that we increment to the first region.
1181 _coarse_cur_region_index = -1;
1182 _coarse_cur_region_cur_card = (PosParPRT::CardsPerRegion-1);;
1184 _cur_region_cur_card = 0;
1186 _fine_array_index = -1;
1187 _fine_cur_prt = NULL;
1189 _n_yielded_coarse = 0;
1190 _n_yielded_fine = 0;
1191 _n_yielded_sparse = 0;
1193 _sparse_iter.init(&hrrs->_other_regions._sparse_table);
1194 }
1196 bool HeapRegionRemSetIterator::coarse_has_next(size_t& card_index) {
1197 if (_hrrs->_other_regions._n_coarse_entries == 0) return false;
1198 // Go to the next card.
1199 _coarse_cur_region_cur_card++;
1200 // Was the last the last card in the current region?
1201 if (_coarse_cur_region_cur_card == PosParPRT::CardsPerRegion) {
1202 // Yes: find the next region. This may leave _coarse_cur_region_index
1203 // Set to the last index, in which case there are no more coarse
1204 // regions.
1205 _coarse_cur_region_index =
1206 (int) _coarse_map->get_next_one_offset(_coarse_cur_region_index + 1);
1207 if ((size_t)_coarse_cur_region_index < _coarse_map->size()) {
1208 _coarse_cur_region_cur_card = 0;
1209 HeapWord* r_bot =
1210 _g1h->region_at(_coarse_cur_region_index)->bottom();
1211 _cur_region_card_offset = _bosa->index_for(r_bot);
1212 } else {
1213 return false;
1214 }
1215 }
1216 // If we didn't return false above, then we can yield a card.
1217 card_index = _cur_region_card_offset + _coarse_cur_region_cur_card;
1218 return true;
1219 }
1221 void HeapRegionRemSetIterator::fine_find_next_non_null_prt() {
1222 // Otherwise, find the next bucket list in the array.
1223 _fine_array_index++;
1224 while (_fine_array_index < (int) OtherRegionsTable::_max_fine_entries) {
1225 _fine_cur_prt = _fine_grain_regions[_fine_array_index];
1226 if (_fine_cur_prt != NULL) return;
1227 else _fine_array_index++;
1228 }
1229 assert(_fine_cur_prt == NULL, "Loop post");
1230 }
1232 bool HeapRegionRemSetIterator::fine_has_next(size_t& card_index) {
1233 if (fine_has_next()) {
1234 _cur_region_cur_card =
1235 _fine_cur_prt->_bm.get_next_one_offset(_cur_region_cur_card + 1);
1236 }
1237 while (!fine_has_next()) {
1238 if (_cur_region_cur_card == PosParPRT::CardsPerRegion) {
1239 _cur_region_cur_card = 0;
1240 _fine_cur_prt = _fine_cur_prt->next();
1241 }
1242 if (_fine_cur_prt == NULL) {
1243 fine_find_next_non_null_prt();
1244 if (_fine_cur_prt == NULL) return false;
1245 }
1246 assert(_fine_cur_prt != NULL && _cur_region_cur_card == 0,
1247 "inv.");
1248 HeapWord* r_bot =
1249 _fine_cur_prt->hr()->bottom();
1250 _cur_region_card_offset = _bosa->index_for(r_bot);
1251 _cur_region_cur_card = _fine_cur_prt->_bm.get_next_one_offset(0);
1252 }
1253 assert(fine_has_next(), "Or else we exited the loop via the return.");
1254 card_index = _cur_region_card_offset + _cur_region_cur_card;
1255 return true;
1256 }
1258 bool HeapRegionRemSetIterator::fine_has_next() {
1259 return
1260 _fine_cur_prt != NULL &&
1261 _cur_region_cur_card < PosParPRT::CardsPerRegion;
1262 }
1264 bool HeapRegionRemSetIterator::has_next(size_t& card_index) {
1265 switch (_is) {
1266 case Sparse:
1267 if (_sparse_iter.has_next(card_index)) {
1268 _n_yielded_sparse++;
1269 return true;
1270 }
1271 // Otherwise, deliberate fall-through
1272 _is = Fine;
1273 case Fine:
1274 if (fine_has_next(card_index)) {
1275 _n_yielded_fine++;
1276 return true;
1277 }
1278 // Otherwise, deliberate fall-through
1279 _is = Coarse;
1280 case Coarse:
1281 if (coarse_has_next(card_index)) {
1282 _n_yielded_coarse++;
1283 return true;
1284 }
1285 // Otherwise...
1286 break;
1287 }
1288 assert(ParallelGCThreads > 1 ||
1289 n_yielded() == _hrrs->occupied(),
1290 "Should have yielded all the cards in the rem set "
1291 "(in the non-par case).");
1292 return false;
1293 }
1297 oop** HeapRegionRemSet::_recorded_oops = NULL;
1298 HeapWord** HeapRegionRemSet::_recorded_cards = NULL;
1299 HeapRegion** HeapRegionRemSet::_recorded_regions = NULL;
1300 int HeapRegionRemSet::_n_recorded = 0;
1302 HeapRegionRemSet::Event* HeapRegionRemSet::_recorded_events = NULL;
1303 int* HeapRegionRemSet::_recorded_event_index = NULL;
1304 int HeapRegionRemSet::_n_recorded_events = 0;
1306 void HeapRegionRemSet::record(HeapRegion* hr, oop* f) {
1307 if (_recorded_oops == NULL) {
1308 assert(_n_recorded == 0
1309 && _recorded_cards == NULL
1310 && _recorded_regions == NULL,
1311 "Inv");
1312 _recorded_oops = NEW_C_HEAP_ARRAY(oop*, MaxRecorded);
1313 _recorded_cards = NEW_C_HEAP_ARRAY(HeapWord*, MaxRecorded);
1314 _recorded_regions = NEW_C_HEAP_ARRAY(HeapRegion*, MaxRecorded);
1315 }
1316 if (_n_recorded == MaxRecorded) {
1317 gclog_or_tty->print_cr("Filled up 'recorded' (%d).", MaxRecorded);
1318 } else {
1319 _recorded_cards[_n_recorded] =
1320 (HeapWord*)align_size_down(uintptr_t(f),
1321 CardTableModRefBS::card_size);
1322 _recorded_oops[_n_recorded] = f;
1323 _recorded_regions[_n_recorded] = hr;
1324 _n_recorded++;
1325 }
1326 }
1328 void HeapRegionRemSet::record_event(Event evnt) {
1329 if (!G1RecordHRRSEvents) return;
1331 if (_recorded_events == NULL) {
1332 assert(_n_recorded_events == 0
1333 && _recorded_event_index == NULL,
1334 "Inv");
1335 _recorded_events = NEW_C_HEAP_ARRAY(Event, MaxRecordedEvents);
1336 _recorded_event_index = NEW_C_HEAP_ARRAY(int, MaxRecordedEvents);
1337 }
1338 if (_n_recorded_events == MaxRecordedEvents) {
1339 gclog_or_tty->print_cr("Filled up 'recorded_events' (%d).", MaxRecordedEvents);
1340 } else {
1341 _recorded_events[_n_recorded_events] = evnt;
1342 _recorded_event_index[_n_recorded_events] = _n_recorded;
1343 _n_recorded_events++;
1344 }
1345 }
1347 void HeapRegionRemSet::print_event(outputStream* str, Event evnt) {
1348 switch (evnt) {
1349 case Event_EvacStart:
1350 str->print("Evac Start");
1351 break;
1352 case Event_EvacEnd:
1353 str->print("Evac End");
1354 break;
1355 case Event_RSUpdateEnd:
1356 str->print("RS Update End");
1357 break;
1358 }
1359 }
1361 void HeapRegionRemSet::print_recorded() {
1362 int cur_evnt = 0;
1363 Event cur_evnt_kind;
1364 int cur_evnt_ind = 0;
1365 if (_n_recorded_events > 0) {
1366 cur_evnt_kind = _recorded_events[cur_evnt];
1367 cur_evnt_ind = _recorded_event_index[cur_evnt];
1368 }
1370 for (int i = 0; i < _n_recorded; i++) {
1371 while (cur_evnt < _n_recorded_events && i == cur_evnt_ind) {
1372 gclog_or_tty->print("Event: ");
1373 print_event(gclog_or_tty, cur_evnt_kind);
1374 gclog_or_tty->print_cr("");
1375 cur_evnt++;
1376 if (cur_evnt < MaxRecordedEvents) {
1377 cur_evnt_kind = _recorded_events[cur_evnt];
1378 cur_evnt_ind = _recorded_event_index[cur_evnt];
1379 }
1380 }
1381 gclog_or_tty->print("Added card " PTR_FORMAT " to region [" PTR_FORMAT "...]"
1382 " for ref " PTR_FORMAT ".\n",
1383 _recorded_cards[i], _recorded_regions[i]->bottom(),
1384 _recorded_oops[i]);
1385 }
1386 }
1388 #ifndef PRODUCT
1389 void HeapRegionRemSet::test() {
1390 os::sleep(Thread::current(), (jlong)5000, false);
1391 G1CollectedHeap* g1h = G1CollectedHeap::heap();
1393 // Run with "-XX:G1LogRSRegionEntries=2", so that 1 and 5 end up in same
1394 // hash bucket.
1395 HeapRegion* hr0 = g1h->region_at(0);
1396 HeapRegion* hr1 = g1h->region_at(1);
1397 HeapRegion* hr2 = g1h->region_at(5);
1398 HeapRegion* hr3 = g1h->region_at(6);
1399 HeapRegion* hr4 = g1h->region_at(7);
1400 HeapRegion* hr5 = g1h->region_at(8);
1402 HeapWord* hr1_start = hr1->bottom();
1403 HeapWord* hr1_mid = hr1_start + HeapRegion::GrainWords/2;
1404 HeapWord* hr1_last = hr1->end() - 1;
1406 HeapWord* hr2_start = hr2->bottom();
1407 HeapWord* hr2_mid = hr2_start + HeapRegion::GrainWords/2;
1408 HeapWord* hr2_last = hr2->end() - 1;
1410 HeapWord* hr3_start = hr3->bottom();
1411 HeapWord* hr3_mid = hr3_start + HeapRegion::GrainWords/2;
1412 HeapWord* hr3_last = hr3->end() - 1;
1414 HeapRegionRemSet* hrrs = hr0->rem_set();
1416 // Make three references from region 0x101...
1417 hrrs->add_reference((oop*)hr1_start);
1418 hrrs->add_reference((oop*)hr1_mid);
1419 hrrs->add_reference((oop*)hr1_last);
1421 hrrs->add_reference((oop*)hr2_start);
1422 hrrs->add_reference((oop*)hr2_mid);
1423 hrrs->add_reference((oop*)hr2_last);
1425 hrrs->add_reference((oop*)hr3_start);
1426 hrrs->add_reference((oop*)hr3_mid);
1427 hrrs->add_reference((oop*)hr3_last);
1429 // Now cause a coarsening.
1430 hrrs->add_reference((oop*)hr4->bottom());
1431 hrrs->add_reference((oop*)hr5->bottom());
1433 // Now, does iteration yield these three?
1434 HeapRegionRemSetIterator iter;
1435 hrrs->init_iterator(&iter);
1436 size_t sum = 0;
1437 size_t card_index;
1438 while (iter.has_next(card_index)) {
1439 HeapWord* card_start =
1440 G1CollectedHeap::heap()->bot_shared()->address_for_index(card_index);
1441 gclog_or_tty->print_cr(" Card " PTR_FORMAT ".", card_start);
1442 sum++;
1443 }
1444 guarantee(sum == 11 - 3 + 2048, "Failure");
1445 guarantee(sum == hrrs->occupied(), "Failure");
1446 }
1447 #endif
