Tue, 18 Mar 2014 19:07:22 +0100
8029075: String deduplication in G1
Summary: Implementation of JEP 192, http://openjdk.java.net/jeps/192
Reviewed-by: brutisso, tschatzl, coleenp
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 */
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 "utilities/bitMap.inline.hpp"
36 #include "utilities/globalDefinitions.hpp"
37 #include "utilities/growableArray.hpp"
39 class PerRegionTable: public CHeapObj<mtGC> {
40 friend class OtherRegionsTable;
41 friend class HeapRegionRemSetIterator;
43 HeapRegion* _hr;
44 BitMap _bm;
45 jint _occupied;
47 // next pointer for free/allocated 'all' list
48 PerRegionTable* _next;
50 // prev pointer for the allocated 'all' list
51 PerRegionTable* _prev;
53 // next pointer in collision list
54 PerRegionTable * _collision_list_next;
56 // Global free list of PRTs
57 static PerRegionTable* _free_list;
59 protected:
60 // We need access in order to union things into the base table.
61 BitMap* bm() { return &_bm; }
63 void recount_occupied() {
64 _occupied = (jint) bm()->count_one_bits();
65 }
67 PerRegionTable(HeapRegion* hr) :
68 _hr(hr),
69 _occupied(0),
70 _bm(HeapRegion::CardsPerRegion, false /* in-resource-area */),
71 _collision_list_next(NULL), _next(NULL), _prev(NULL)
72 {}
74 void add_card_work(CardIdx_t from_card, bool par) {
75 if (!_bm.at(from_card)) {
76 if (par) {
77 if (_bm.par_at_put(from_card, 1)) {
78 Atomic::inc(&_occupied);
79 }
80 } else {
81 _bm.at_put(from_card, 1);
82 _occupied++;
83 }
84 }
85 }
87 void add_reference_work(OopOrNarrowOopStar from, bool par) {
88 // Must make this robust in case "from" is not in "_hr", because of
89 // concurrency.
91 if (G1TraceHeapRegionRememberedSet) {
92 gclog_or_tty->print_cr(" PRT::Add_reference_work(" PTR_FORMAT "->" PTR_FORMAT").",
93 from,
94 UseCompressedOops
95 ? (void *)oopDesc::load_decode_heap_oop((narrowOop*)from)
96 : (void *)oopDesc::load_decode_heap_oop((oop*)from));
97 }
99 HeapRegion* loc_hr = hr();
100 // If the test below fails, then this table was reused concurrently
101 // with this operation. This is OK, since the old table was coarsened,
102 // and adding a bit to the new table is never incorrect.
103 // If the table used to belong to a continues humongous region and is
104 // now reused for the corresponding start humongous region, we need to
105 // make sure that we detect this. Thus, we call is_in_reserved_raw()
106 // instead of just is_in_reserved() here.
107 if (loc_hr->is_in_reserved_raw(from)) {
108 size_t hw_offset = pointer_delta((HeapWord*)from, loc_hr->bottom());
109 CardIdx_t from_card = (CardIdx_t)
110 hw_offset >> (CardTableModRefBS::card_shift - LogHeapWordSize);
112 assert(0 <= from_card && (size_t)from_card < HeapRegion::CardsPerRegion,
113 "Must be in range.");
114 add_card_work(from_card, par);
115 }
116 }
118 public:
120 HeapRegion* hr() const { return _hr; }
122 jint occupied() const {
123 // Overkill, but if we ever need it...
124 // guarantee(_occupied == _bm.count_one_bits(), "Check");
125 return _occupied;
126 }
128 void init(HeapRegion* hr, bool clear_links_to_all_list) {
129 if (clear_links_to_all_list) {
130 set_next(NULL);
131 set_prev(NULL);
132 }
133 _hr = hr;
134 _collision_list_next = NULL;
135 _occupied = 0;
136 _bm.clear();
137 }
139 void add_reference(OopOrNarrowOopStar from) {
140 add_reference_work(from, /*parallel*/ true);
141 }
143 void seq_add_reference(OopOrNarrowOopStar from) {
144 add_reference_work(from, /*parallel*/ false);
145 }
147 void scrub(CardTableModRefBS* ctbs, BitMap* card_bm) {
148 HeapWord* hr_bot = hr()->bottom();
149 size_t hr_first_card_index = ctbs->index_for(hr_bot);
150 bm()->set_intersection_at_offset(*card_bm, hr_first_card_index);
151 recount_occupied();
152 }
154 void add_card(CardIdx_t from_card_index) {
155 add_card_work(from_card_index, /*parallel*/ true);
156 }
158 void seq_add_card(CardIdx_t from_card_index) {
159 add_card_work(from_card_index, /*parallel*/ false);
160 }
162 // (Destructively) union the bitmap of the current table into the given
163 // bitmap (which is assumed to be of the same size.)
164 void union_bitmap_into(BitMap* bm) {
165 bm->set_union(_bm);
166 }
168 // Mem size in bytes.
169 size_t mem_size() const {
170 return sizeof(this) + _bm.size_in_words() * HeapWordSize;
171 }
173 // Requires "from" to be in "hr()".
174 bool contains_reference(OopOrNarrowOopStar from) const {
175 assert(hr()->is_in_reserved(from), "Precondition.");
176 size_t card_ind = pointer_delta(from, hr()->bottom(),
177 CardTableModRefBS::card_size);
178 return _bm.at(card_ind);
179 }
181 // Bulk-free the PRTs from prt to last, assumes that they are
182 // linked together using their _next field.
183 static void bulk_free(PerRegionTable* prt, PerRegionTable* last) {
184 while (true) {
185 PerRegionTable* fl = _free_list;
186 last->set_next(fl);
187 PerRegionTable* res = (PerRegionTable*) Atomic::cmpxchg_ptr(prt, &_free_list, fl);
188 if (res == fl) {
189 return;
190 }
191 }
192 ShouldNotReachHere();
193 }
195 static void free(PerRegionTable* prt) {
196 bulk_free(prt, prt);
197 }
199 // Returns an initialized PerRegionTable instance.
200 static PerRegionTable* alloc(HeapRegion* hr) {
201 PerRegionTable* fl = _free_list;
202 while (fl != NULL) {
203 PerRegionTable* nxt = fl->next();
204 PerRegionTable* res =
205 (PerRegionTable*)
206 Atomic::cmpxchg_ptr(nxt, &_free_list, fl);
207 if (res == fl) {
208 fl->init(hr, true);
209 return fl;
210 } else {
211 fl = _free_list;
212 }
213 }
214 assert(fl == NULL, "Loop condition.");
215 return new PerRegionTable(hr);
216 }
218 PerRegionTable* next() const { return _next; }
219 void set_next(PerRegionTable* next) { _next = next; }
220 PerRegionTable* prev() const { return _prev; }
221 void set_prev(PerRegionTable* prev) { _prev = prev; }
223 // Accessor and Modification routines for the pointer for the
224 // singly linked collision list that links the PRTs within the
225 // OtherRegionsTable::_fine_grain_regions hash table.
226 //
227 // It might be useful to also make the collision list doubly linked
228 // to avoid iteration over the collisions list during scrubbing/deletion.
229 // OTOH there might not be many collisions.
231 PerRegionTable* collision_list_next() const {
232 return _collision_list_next;
233 }
235 void set_collision_list_next(PerRegionTable* next) {
236 _collision_list_next = next;
237 }
239 PerRegionTable** collision_list_next_addr() {
240 return &_collision_list_next;
241 }
243 static size_t fl_mem_size() {
244 PerRegionTable* cur = _free_list;
245 size_t res = 0;
246 while (cur != NULL) {
247 res += cur->mem_size();
248 cur = cur->next();
249 }
250 return res;
251 }
253 static void test_fl_mem_size();
254 };
256 PerRegionTable* PerRegionTable::_free_list = NULL;
258 size_t OtherRegionsTable::_max_fine_entries = 0;
259 size_t OtherRegionsTable::_mod_max_fine_entries_mask = 0;
260 size_t OtherRegionsTable::_fine_eviction_stride = 0;
261 size_t OtherRegionsTable::_fine_eviction_sample_size = 0;
263 OtherRegionsTable::OtherRegionsTable(HeapRegion* hr, Mutex* m) :
264 _g1h(G1CollectedHeap::heap()),
265 _hr(hr), _m(m),
266 _coarse_map(G1CollectedHeap::heap()->max_regions(),
267 false /* in-resource-area */),
268 _fine_grain_regions(NULL),
269 _first_all_fine_prts(NULL), _last_all_fine_prts(NULL),
270 _n_fine_entries(0), _n_coarse_entries(0),
271 _fine_eviction_start(0),
272 _sparse_table(hr)
273 {
274 typedef PerRegionTable* PerRegionTablePtr;
276 if (_max_fine_entries == 0) {
277 assert(_mod_max_fine_entries_mask == 0, "Both or none.");
278 size_t max_entries_log = (size_t)log2_long((jlong)G1RSetRegionEntries);
279 _max_fine_entries = (size_t)1 << max_entries_log;
280 _mod_max_fine_entries_mask = _max_fine_entries - 1;
282 assert(_fine_eviction_sample_size == 0
283 && _fine_eviction_stride == 0, "All init at same time.");
284 _fine_eviction_sample_size = MAX2((size_t)4, max_entries_log);
285 _fine_eviction_stride = _max_fine_entries / _fine_eviction_sample_size;
286 }
288 _fine_grain_regions = NEW_C_HEAP_ARRAY3(PerRegionTablePtr, _max_fine_entries,
289 mtGC, 0, AllocFailStrategy::RETURN_NULL);
291 if (_fine_grain_regions == NULL) {
292 vm_exit_out_of_memory(sizeof(void*)*_max_fine_entries, OOM_MALLOC_ERROR,
293 "Failed to allocate _fine_grain_entries.");
294 }
296 for (size_t i = 0; i < _max_fine_entries; i++) {
297 _fine_grain_regions[i] = NULL;
298 }
299 }
301 void OtherRegionsTable::link_to_all(PerRegionTable* prt) {
302 // We always append to the beginning of the list for convenience;
303 // the order of entries in this list does not matter.
304 if (_first_all_fine_prts != NULL) {
305 assert(_first_all_fine_prts->prev() == NULL, "invariant");
306 _first_all_fine_prts->set_prev(prt);
307 prt->set_next(_first_all_fine_prts);
308 } else {
309 // this is the first element we insert. Adjust the "last" pointer
310 _last_all_fine_prts = prt;
311 assert(prt->next() == NULL, "just checking");
312 }
313 // the new element is always the first element without a predecessor
314 prt->set_prev(NULL);
315 _first_all_fine_prts = prt;
317 assert(prt->prev() == NULL, "just checking");
318 assert(_first_all_fine_prts == prt, "just checking");
319 assert((_first_all_fine_prts == NULL && _last_all_fine_prts == NULL) ||
320 (_first_all_fine_prts != NULL && _last_all_fine_prts != NULL),
321 "just checking");
322 assert(_last_all_fine_prts == NULL || _last_all_fine_prts->next() == NULL,
323 "just checking");
324 assert(_first_all_fine_prts == NULL || _first_all_fine_prts->prev() == NULL,
325 "just checking");
326 }
328 void OtherRegionsTable::unlink_from_all(PerRegionTable* prt) {
329 if (prt->prev() != NULL) {
330 assert(_first_all_fine_prts != prt, "just checking");
331 prt->prev()->set_next(prt->next());
332 // removing the last element in the list?
333 if (_last_all_fine_prts == prt) {
334 _last_all_fine_prts = prt->prev();
335 }
336 } else {
337 assert(_first_all_fine_prts == prt, "just checking");
338 _first_all_fine_prts = prt->next();
339 // list is empty now?
340 if (_first_all_fine_prts == NULL) {
341 _last_all_fine_prts = NULL;
342 }
343 }
345 if (prt->next() != NULL) {
346 prt->next()->set_prev(prt->prev());
347 }
349 prt->set_next(NULL);
350 prt->set_prev(NULL);
352 assert((_first_all_fine_prts == NULL && _last_all_fine_prts == NULL) ||
353 (_first_all_fine_prts != NULL && _last_all_fine_prts != NULL),
354 "just checking");
355 assert(_last_all_fine_prts == NULL || _last_all_fine_prts->next() == NULL,
356 "just checking");
357 assert(_first_all_fine_prts == NULL || _first_all_fine_prts->prev() == NULL,
358 "just checking");
359 }
361 int** FromCardCache::_cache = NULL;
362 uint FromCardCache::_max_regions = 0;
363 size_t FromCardCache::_static_mem_size = 0;
365 void FromCardCache::initialize(uint n_par_rs, uint max_num_regions) {
366 guarantee(_cache == NULL, "Should not call this multiple times");
368 _max_regions = max_num_regions;
369 _cache = Padded2DArray<int, mtGC>::create_unfreeable(n_par_rs,
370 _max_regions,
371 &_static_mem_size);
373 for (uint i = 0; i < n_par_rs; i++) {
374 for (uint j = 0; j < _max_regions; j++) {
375 set(i, j, InvalidCard);
376 }
377 }
378 }
380 void FromCardCache::shrink(uint new_num_regions) {
381 for (uint i = 0; i < HeapRegionRemSet::num_par_rem_sets(); i++) {
382 assert(new_num_regions <= _max_regions, "Must be within max.");
383 for (uint j = new_num_regions; j < _max_regions; j++) {
384 set(i, j, InvalidCard);
385 }
386 }
387 }
389 #ifndef PRODUCT
390 void FromCardCache::print(outputStream* out) {
391 for (uint i = 0; i < HeapRegionRemSet::num_par_rem_sets(); i++) {
392 for (uint j = 0; j < _max_regions; j++) {
393 out->print_cr("_from_card_cache["UINT32_FORMAT"]["UINT32_FORMAT"] = "INT32_FORMAT".",
394 i, j, at(i, j));
395 }
396 }
397 }
398 #endif
400 void FromCardCache::clear(uint region_idx) {
401 uint num_par_remsets = HeapRegionRemSet::num_par_rem_sets();
402 for (uint i = 0; i < num_par_remsets; i++) {
403 set(i, region_idx, InvalidCard);
404 }
405 }
407 void OtherRegionsTable::init_from_card_cache(uint max_regions) {
408 FromCardCache::initialize(HeapRegionRemSet::num_par_rem_sets(), max_regions);
409 }
411 void OtherRegionsTable::shrink_from_card_cache(uint new_num_regions) {
412 FromCardCache::shrink(new_num_regions);
413 }
415 void OtherRegionsTable::print_from_card_cache() {
416 FromCardCache::print();
417 }
419 void OtherRegionsTable::add_reference(OopOrNarrowOopStar from, int tid) {
420 uint cur_hrs_ind = hr()->hrs_index();
422 if (G1TraceHeapRegionRememberedSet) {
423 gclog_or_tty->print_cr("ORT::add_reference_work(" PTR_FORMAT "->" PTR_FORMAT ").",
424 from,
425 UseCompressedOops
426 ? (void *)oopDesc::load_decode_heap_oop((narrowOop*)from)
427 : (void *)oopDesc::load_decode_heap_oop((oop*)from));
428 }
430 int from_card = (int)(uintptr_t(from) >> CardTableModRefBS::card_shift);
432 if (G1TraceHeapRegionRememberedSet) {
433 gclog_or_tty->print_cr("Table for [" PTR_FORMAT "...): card %d (cache = "INT32_FORMAT")",
434 hr()->bottom(), from_card,
435 FromCardCache::at((uint)tid, cur_hrs_ind));
436 }
438 if (FromCardCache::contains_or_replace((uint)tid, cur_hrs_ind, from_card)) {
439 if (G1TraceHeapRegionRememberedSet) {
440 gclog_or_tty->print_cr(" from-card cache hit.");
441 }
442 assert(contains_reference(from), "We just added it!");
443 return;
444 }
446 // Note that this may be a continued H region.
447 HeapRegion* from_hr = _g1h->heap_region_containing_raw(from);
448 RegionIdx_t from_hrs_ind = (RegionIdx_t) from_hr->hrs_index();
450 // If the region is already coarsened, return.
451 if (_coarse_map.at(from_hrs_ind)) {
452 if (G1TraceHeapRegionRememberedSet) {
453 gclog_or_tty->print_cr(" coarse map hit.");
454 }
455 assert(contains_reference(from), "We just added it!");
456 return;
457 }
459 // Otherwise find a per-region table to add it to.
460 size_t ind = from_hrs_ind & _mod_max_fine_entries_mask;
461 PerRegionTable* prt = find_region_table(ind, from_hr);
462 if (prt == NULL) {
463 MutexLockerEx x(_m, Mutex::_no_safepoint_check_flag);
464 // Confirm that it's really not there...
465 prt = find_region_table(ind, from_hr);
466 if (prt == NULL) {
468 uintptr_t from_hr_bot_card_index =
469 uintptr_t(from_hr->bottom())
470 >> CardTableModRefBS::card_shift;
471 CardIdx_t card_index = from_card - from_hr_bot_card_index;
472 assert(0 <= card_index && (size_t)card_index < HeapRegion::CardsPerRegion,
473 "Must be in range.");
474 if (G1HRRSUseSparseTable &&
475 _sparse_table.add_card(from_hrs_ind, card_index)) {
476 if (G1RecordHRRSOops) {
477 HeapRegionRemSet::record(hr(), from);
478 if (G1TraceHeapRegionRememberedSet) {
479 gclog_or_tty->print(" Added card " PTR_FORMAT " to region "
480 "[" PTR_FORMAT "...) for ref " PTR_FORMAT ".\n",
481 align_size_down(uintptr_t(from),
482 CardTableModRefBS::card_size),
483 hr()->bottom(), from);
484 }
485 }
486 if (G1TraceHeapRegionRememberedSet) {
487 gclog_or_tty->print_cr(" added card to sparse table.");
488 }
489 assert(contains_reference_locked(from), "We just added it!");
490 return;
491 } else {
492 if (G1TraceHeapRegionRememberedSet) {
493 gclog_or_tty->print_cr(" [tid %d] sparse table entry "
494 "overflow(f: %d, t: %d)",
495 tid, from_hrs_ind, cur_hrs_ind);
496 }
497 }
499 if (_n_fine_entries == _max_fine_entries) {
500 prt = delete_region_table();
501 // There is no need to clear the links to the 'all' list here:
502 // prt will be reused immediately, i.e. remain in the 'all' list.
503 prt->init(from_hr, false /* clear_links_to_all_list */);
504 } else {
505 prt = PerRegionTable::alloc(from_hr);
506 link_to_all(prt);
507 }
509 PerRegionTable* first_prt = _fine_grain_regions[ind];
510 prt->set_collision_list_next(first_prt);
511 _fine_grain_regions[ind] = prt;
512 _n_fine_entries++;
514 if (G1HRRSUseSparseTable) {
515 // Transfer from sparse to fine-grain.
516 SparsePRTEntry *sprt_entry = _sparse_table.get_entry(from_hrs_ind);
517 assert(sprt_entry != NULL, "There should have been an entry");
518 for (int i = 0; i < SparsePRTEntry::cards_num(); i++) {
519 CardIdx_t c = sprt_entry->card(i);
520 if (c != SparsePRTEntry::NullEntry) {
521 prt->add_card(c);
522 }
523 }
524 // Now we can delete the sparse entry.
525 bool res = _sparse_table.delete_entry(from_hrs_ind);
526 assert(res, "It should have been there.");
527 }
528 }
529 assert(prt != NULL && prt->hr() == from_hr, "consequence");
530 }
531 // Note that we can't assert "prt->hr() == from_hr", because of the
532 // possibility of concurrent reuse. But see head comment of
533 // OtherRegionsTable for why this is OK.
534 assert(prt != NULL, "Inv");
536 prt->add_reference(from);
538 if (G1RecordHRRSOops) {
539 HeapRegionRemSet::record(hr(), from);
540 if (G1TraceHeapRegionRememberedSet) {
541 gclog_or_tty->print("Added card " PTR_FORMAT " to region "
542 "[" PTR_FORMAT "...) for ref " PTR_FORMAT ".\n",
543 align_size_down(uintptr_t(from),
544 CardTableModRefBS::card_size),
545 hr()->bottom(), from);
546 }
547 }
548 assert(contains_reference(from), "We just added it!");
549 }
551 PerRegionTable*
552 OtherRegionsTable::find_region_table(size_t ind, HeapRegion* hr) const {
553 assert(0 <= ind && ind < _max_fine_entries, "Preconditions.");
554 PerRegionTable* prt = _fine_grain_regions[ind];
555 while (prt != NULL && prt->hr() != hr) {
556 prt = prt->collision_list_next();
557 }
558 // Loop postcondition is the method postcondition.
559 return prt;
560 }
562 jint OtherRegionsTable::_n_coarsenings = 0;
564 PerRegionTable* OtherRegionsTable::delete_region_table() {
565 assert(_m->owned_by_self(), "Precondition");
566 assert(_n_fine_entries == _max_fine_entries, "Precondition");
567 PerRegionTable* max = NULL;
568 jint max_occ = 0;
569 PerRegionTable** max_prev;
570 size_t max_ind;
572 size_t i = _fine_eviction_start;
573 for (size_t k = 0; k < _fine_eviction_sample_size; k++) {
574 size_t ii = i;
575 // Make sure we get a non-NULL sample.
576 while (_fine_grain_regions[ii] == NULL) {
577 ii++;
578 if (ii == _max_fine_entries) ii = 0;
579 guarantee(ii != i, "We must find one.");
580 }
581 PerRegionTable** prev = &_fine_grain_regions[ii];
582 PerRegionTable* cur = *prev;
583 while (cur != NULL) {
584 jint cur_occ = cur->occupied();
585 if (max == NULL || cur_occ > max_occ) {
586 max = cur;
587 max_prev = prev;
588 max_ind = i;
589 max_occ = cur_occ;
590 }
591 prev = cur->collision_list_next_addr();
592 cur = cur->collision_list_next();
593 }
594 i = i + _fine_eviction_stride;
595 if (i >= _n_fine_entries) i = i - _n_fine_entries;
596 }
598 _fine_eviction_start++;
600 if (_fine_eviction_start >= _n_fine_entries) {
601 _fine_eviction_start -= _n_fine_entries;
602 }
604 guarantee(max != NULL, "Since _n_fine_entries > 0");
606 // Set the corresponding coarse bit.
607 size_t max_hrs_index = (size_t) max->hr()->hrs_index();
608 if (!_coarse_map.at(max_hrs_index)) {
609 _coarse_map.at_put(max_hrs_index, true);
610 _n_coarse_entries++;
611 if (G1TraceHeapRegionRememberedSet) {
612 gclog_or_tty->print("Coarsened entry in region [" PTR_FORMAT "...] "
613 "for region [" PTR_FORMAT "...] (%d coarse entries).\n",
614 hr()->bottom(),
615 max->hr()->bottom(),
616 _n_coarse_entries);
617 }
618 }
620 // Unsplice.
621 *max_prev = max->collision_list_next();
622 Atomic::inc(&_n_coarsenings);
623 _n_fine_entries--;
624 return max;
625 }
628 // At present, this must be called stop-world single-threaded.
629 void OtherRegionsTable::scrub(CardTableModRefBS* ctbs,
630 BitMap* region_bm, BitMap* card_bm) {
631 // First eliminated garbage regions from the coarse map.
632 if (G1RSScrubVerbose) {
633 gclog_or_tty->print_cr("Scrubbing region %u:", hr()->hrs_index());
634 }
636 assert(_coarse_map.size() == region_bm->size(), "Precondition");
637 if (G1RSScrubVerbose) {
638 gclog_or_tty->print(" Coarse map: before = "SIZE_FORMAT"...",
639 _n_coarse_entries);
640 }
641 _coarse_map.set_intersection(*region_bm);
642 _n_coarse_entries = _coarse_map.count_one_bits();
643 if (G1RSScrubVerbose) {
644 gclog_or_tty->print_cr(" after = "SIZE_FORMAT".", _n_coarse_entries);
645 }
647 // Now do the fine-grained maps.
648 for (size_t i = 0; i < _max_fine_entries; i++) {
649 PerRegionTable* cur = _fine_grain_regions[i];
650 PerRegionTable** prev = &_fine_grain_regions[i];
651 while (cur != NULL) {
652 PerRegionTable* nxt = cur->collision_list_next();
653 // If the entire region is dead, eliminate.
654 if (G1RSScrubVerbose) {
655 gclog_or_tty->print_cr(" For other region %u:",
656 cur->hr()->hrs_index());
657 }
658 if (!region_bm->at((size_t) cur->hr()->hrs_index())) {
659 *prev = nxt;
660 cur->set_collision_list_next(NULL);
661 _n_fine_entries--;
662 if (G1RSScrubVerbose) {
663 gclog_or_tty->print_cr(" deleted via region map.");
664 }
665 unlink_from_all(cur);
666 PerRegionTable::free(cur);
667 } else {
668 // Do fine-grain elimination.
669 if (G1RSScrubVerbose) {
670 gclog_or_tty->print(" occ: before = %4d.", cur->occupied());
671 }
672 cur->scrub(ctbs, card_bm);
673 if (G1RSScrubVerbose) {
674 gclog_or_tty->print_cr(" after = %4d.", cur->occupied());
675 }
676 // Did that empty the table completely?
677 if (cur->occupied() == 0) {
678 *prev = nxt;
679 cur->set_collision_list_next(NULL);
680 _n_fine_entries--;
681 unlink_from_all(cur);
682 PerRegionTable::free(cur);
683 } else {
684 prev = cur->collision_list_next_addr();
685 }
686 }
687 cur = nxt;
688 }
689 }
690 // Since we may have deleted a from_card_cache entry from the RS, clear
691 // the FCC.
692 clear_fcc();
693 }
696 size_t OtherRegionsTable::occupied() const {
697 size_t sum = occ_fine();
698 sum += occ_sparse();
699 sum += occ_coarse();
700 return sum;
701 }
703 size_t OtherRegionsTable::occ_fine() const {
704 size_t sum = 0;
706 size_t num = 0;
707 PerRegionTable * cur = _first_all_fine_prts;
708 while (cur != NULL) {
709 sum += cur->occupied();
710 cur = cur->next();
711 num++;
712 }
713 guarantee(num == _n_fine_entries, "just checking");
714 return sum;
715 }
717 size_t OtherRegionsTable::occ_coarse() const {
718 return (_n_coarse_entries * HeapRegion::CardsPerRegion);
719 }
721 size_t OtherRegionsTable::occ_sparse() const {
722 return _sparse_table.occupied();
723 }
725 size_t OtherRegionsTable::mem_size() const {
726 size_t sum = 0;
727 // all PRTs are of the same size so it is sufficient to query only one of them.
728 if (_first_all_fine_prts != NULL) {
729 assert(_last_all_fine_prts != NULL &&
730 _first_all_fine_prts->mem_size() == _last_all_fine_prts->mem_size(), "check that mem_size() is constant");
731 sum += _first_all_fine_prts->mem_size() * _n_fine_entries;
732 }
733 sum += (sizeof(PerRegionTable*) * _max_fine_entries);
734 sum += (_coarse_map.size_in_words() * HeapWordSize);
735 sum += (_sparse_table.mem_size());
736 sum += sizeof(*this) - sizeof(_sparse_table); // Avoid double counting above.
737 return sum;
738 }
740 size_t OtherRegionsTable::static_mem_size() {
741 return FromCardCache::static_mem_size();
742 }
744 size_t OtherRegionsTable::fl_mem_size() {
745 return PerRegionTable::fl_mem_size();
746 }
748 void OtherRegionsTable::clear_fcc() {
749 FromCardCache::clear(hr()->hrs_index());
750 }
752 void OtherRegionsTable::clear() {
753 // if there are no entries, skip this step
754 if (_first_all_fine_prts != NULL) {
755 guarantee(_first_all_fine_prts != NULL && _last_all_fine_prts != NULL, "just checking");
756 PerRegionTable::bulk_free(_first_all_fine_prts, _last_all_fine_prts);
757 memset(_fine_grain_regions, 0, _max_fine_entries * sizeof(_fine_grain_regions[0]));
758 } else {
759 guarantee(_first_all_fine_prts == NULL && _last_all_fine_prts == NULL, "just checking");
760 }
762 _first_all_fine_prts = _last_all_fine_prts = NULL;
763 _sparse_table.clear();
764 _coarse_map.clear();
765 _n_fine_entries = 0;
766 _n_coarse_entries = 0;
768 clear_fcc();
769 }
771 void OtherRegionsTable::clear_incoming_entry(HeapRegion* from_hr) {
772 MutexLockerEx x(_m, Mutex::_no_safepoint_check_flag);
773 size_t hrs_ind = (size_t) from_hr->hrs_index();
774 size_t ind = hrs_ind & _mod_max_fine_entries_mask;
775 if (del_single_region_table(ind, from_hr)) {
776 assert(!_coarse_map.at(hrs_ind), "Inv");
777 } else {
778 _coarse_map.par_at_put(hrs_ind, 0);
779 }
780 // Check to see if any of the fcc entries come from here.
781 uint hr_ind = hr()->hrs_index();
782 for (uint tid = 0; tid < HeapRegionRemSet::num_par_rem_sets(); tid++) {
783 int fcc_ent = FromCardCache::at(tid, hr_ind);
784 if (fcc_ent != FromCardCache::InvalidCard) {
785 HeapWord* card_addr = (HeapWord*)
786 (uintptr_t(fcc_ent) << CardTableModRefBS::card_shift);
787 if (hr()->is_in_reserved(card_addr)) {
788 // Clear the from card cache.
789 FromCardCache::set(tid, hr_ind, FromCardCache::InvalidCard);
790 }
791 }
792 }
793 }
795 bool OtherRegionsTable::del_single_region_table(size_t ind,
796 HeapRegion* hr) {
797 assert(0 <= ind && ind < _max_fine_entries, "Preconditions.");
798 PerRegionTable** prev_addr = &_fine_grain_regions[ind];
799 PerRegionTable* prt = *prev_addr;
800 while (prt != NULL && prt->hr() != hr) {
801 prev_addr = prt->collision_list_next_addr();
802 prt = prt->collision_list_next();
803 }
804 if (prt != NULL) {
805 assert(prt->hr() == hr, "Loop postcondition.");
806 *prev_addr = prt->collision_list_next();
807 unlink_from_all(prt);
808 PerRegionTable::free(prt);
809 _n_fine_entries--;
810 return true;
811 } else {
812 return false;
813 }
814 }
816 bool OtherRegionsTable::contains_reference(OopOrNarrowOopStar from) const {
817 // Cast away const in this case.
818 MutexLockerEx x((Mutex*)_m, Mutex::_no_safepoint_check_flag);
819 return contains_reference_locked(from);
820 }
822 bool OtherRegionsTable::contains_reference_locked(OopOrNarrowOopStar from) const {
823 HeapRegion* hr = _g1h->heap_region_containing_raw(from);
824 if (hr == NULL) return false;
825 RegionIdx_t hr_ind = (RegionIdx_t) hr->hrs_index();
826 // Is this region in the coarse map?
827 if (_coarse_map.at(hr_ind)) return true;
829 PerRegionTable* prt = find_region_table(hr_ind & _mod_max_fine_entries_mask,
830 hr);
831 if (prt != NULL) {
832 return prt->contains_reference(from);
834 } else {
835 uintptr_t from_card =
836 (uintptr_t(from) >> CardTableModRefBS::card_shift);
837 uintptr_t hr_bot_card_index =
838 uintptr_t(hr->bottom()) >> CardTableModRefBS::card_shift;
839 assert(from_card >= hr_bot_card_index, "Inv");
840 CardIdx_t card_index = from_card - hr_bot_card_index;
841 assert(0 <= card_index && (size_t)card_index < HeapRegion::CardsPerRegion,
842 "Must be in range.");
843 return _sparse_table.contains_card(hr_ind, card_index);
844 }
845 }
847 void
848 OtherRegionsTable::do_cleanup_work(HRRSCleanupTask* hrrs_cleanup_task) {
849 _sparse_table.do_cleanup_work(hrrs_cleanup_task);
850 }
852 // Determines how many threads can add records to an rset in parallel.
853 // This can be done by either mutator threads together with the
854 // concurrent refinement threads or GC threads.
855 uint HeapRegionRemSet::num_par_rem_sets() {
856 return (uint)MAX2(DirtyCardQueueSet::num_par_ids() + ConcurrentG1Refine::thread_num(), ParallelGCThreads);
857 }
859 HeapRegionRemSet::HeapRegionRemSet(G1BlockOffsetSharedArray* bosa,
860 HeapRegion* hr)
861 : _bosa(bosa),
862 _m(Mutex::leaf, FormatBuffer<128>("HeapRegionRemSet lock #"UINT32_FORMAT, hr->hrs_index()), true),
863 _code_roots(), _other_regions(hr, &_m) {
864 reset_for_par_iteration();
865 }
867 void HeapRegionRemSet::setup_remset_size() {
868 // Setup sparse and fine-grain tables sizes.
869 // table_size = base * (log(region_size / 1M) + 1)
870 const int LOG_M = 20;
871 int region_size_log_mb = MAX2(HeapRegion::LogOfHRGrainBytes - LOG_M, 0);
872 if (FLAG_IS_DEFAULT(G1RSetSparseRegionEntries)) {
873 G1RSetSparseRegionEntries = G1RSetSparseRegionEntriesBase * (region_size_log_mb + 1);
874 }
875 if (FLAG_IS_DEFAULT(G1RSetRegionEntries)) {
876 G1RSetRegionEntries = G1RSetRegionEntriesBase * (region_size_log_mb + 1);
877 }
878 guarantee(G1RSetSparseRegionEntries > 0 && G1RSetRegionEntries > 0 , "Sanity");
879 }
881 bool HeapRegionRemSet::claim_iter() {
882 if (_iter_state != Unclaimed) return false;
883 jint res = Atomic::cmpxchg(Claimed, (jint*)(&_iter_state), Unclaimed);
884 return (res == Unclaimed);
885 }
887 void HeapRegionRemSet::set_iter_complete() {
888 _iter_state = Complete;
889 }
891 bool HeapRegionRemSet::iter_is_complete() {
892 return _iter_state == Complete;
893 }
895 #ifndef PRODUCT
896 void HeapRegionRemSet::print() {
897 HeapRegionRemSetIterator iter(this);
898 size_t card_index;
899 while (iter.has_next(card_index)) {
900 HeapWord* card_start =
901 G1CollectedHeap::heap()->bot_shared()->address_for_index(card_index);
902 gclog_or_tty->print_cr(" Card " PTR_FORMAT, card_start);
903 }
904 if (iter.n_yielded() != occupied()) {
905 gclog_or_tty->print_cr("Yielded disagrees with occupied:");
906 gclog_or_tty->print_cr(" %6d yielded (%6d coarse, %6d fine).",
907 iter.n_yielded(),
908 iter.n_yielded_coarse(), iter.n_yielded_fine());
909 gclog_or_tty->print_cr(" %6d occ (%6d coarse, %6d fine).",
910 occupied(), occ_coarse(), occ_fine());
911 }
912 guarantee(iter.n_yielded() == occupied(),
913 "We should have yielded all the represented cards.");
914 }
915 #endif
917 void HeapRegionRemSet::cleanup() {
918 SparsePRT::cleanup_all();
919 }
921 void HeapRegionRemSet::clear() {
922 MutexLockerEx x(&_m, Mutex::_no_safepoint_check_flag);
923 clear_locked();
924 }
926 void HeapRegionRemSet::clear_locked() {
927 _code_roots.clear();
928 _other_regions.clear();
929 assert(occupied_locked() == 0, "Should be clear.");
930 reset_for_par_iteration();
931 }
933 void HeapRegionRemSet::reset_for_par_iteration() {
934 _iter_state = Unclaimed;
935 _iter_claimed = 0;
936 // It's good to check this to make sure that the two methods are in sync.
937 assert(verify_ready_for_par_iteration(), "post-condition");
938 }
940 void HeapRegionRemSet::scrub(CardTableModRefBS* ctbs,
941 BitMap* region_bm, BitMap* card_bm) {
942 _other_regions.scrub(ctbs, region_bm, card_bm);
943 }
945 // Code roots support
947 void HeapRegionRemSet::add_strong_code_root(nmethod* nm) {
948 assert(nm != NULL, "sanity");
949 _code_roots.add(nm);
950 }
952 void HeapRegionRemSet::remove_strong_code_root(nmethod* nm) {
953 assert(nm != NULL, "sanity");
954 _code_roots.remove(nm);
955 // Check that there were no duplicates
956 guarantee(!_code_roots.contains(nm), "duplicate entry found");
957 }
959 class NMethodMigrationOopClosure : public OopClosure {
960 G1CollectedHeap* _g1h;
961 HeapRegion* _from;
962 nmethod* _nm;
964 uint _num_self_forwarded;
966 template <class T> void do_oop_work(T* p) {
967 T heap_oop = oopDesc::load_heap_oop(p);
968 if (!oopDesc::is_null(heap_oop)) {
969 oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
970 if (_from->is_in(obj)) {
971 // Reference still points into the source region.
972 // Since roots are immediately evacuated this means that
973 // we must have self forwarded the object
974 assert(obj->is_forwarded(),
975 err_msg("code roots should be immediately evacuated. "
976 "Ref: "PTR_FORMAT", "
977 "Obj: "PTR_FORMAT", "
978 "Region: "HR_FORMAT,
979 p, (void*) obj, HR_FORMAT_PARAMS(_from)));
980 assert(obj->forwardee() == obj,
981 err_msg("not self forwarded? obj = "PTR_FORMAT, (void*)obj));
983 // The object has been self forwarded.
984 // Note, if we're during an initial mark pause, there is
985 // no need to explicitly mark object. It will be marked
986 // during the regular evacuation failure handling code.
987 _num_self_forwarded++;
988 } else {
989 // The reference points into a promotion or to-space region
990 HeapRegion* to = _g1h->heap_region_containing(obj);
991 to->rem_set()->add_strong_code_root(_nm);
992 }
993 }
994 }
996 public:
997 NMethodMigrationOopClosure(G1CollectedHeap* g1h, HeapRegion* from, nmethod* nm):
998 _g1h(g1h), _from(from), _nm(nm), _num_self_forwarded(0) {}
1000 void do_oop(narrowOop* p) { do_oop_work(p); }
1001 void do_oop(oop* p) { do_oop_work(p); }
1003 uint retain() { return _num_self_forwarded > 0; }
1004 };
1006 void HeapRegionRemSet::migrate_strong_code_roots() {
1007 assert(hr()->in_collection_set(), "only collection set regions");
1008 assert(!hr()->isHumongous(),
1009 err_msg("humongous region "HR_FORMAT" should not have been added to the collection set",
1010 HR_FORMAT_PARAMS(hr())));
1012 ResourceMark rm;
1014 // List of code blobs to retain for this region
1015 GrowableArray<nmethod*> to_be_retained(10);
1016 G1CollectedHeap* g1h = G1CollectedHeap::heap();
1018 while (!_code_roots.is_empty()) {
1019 nmethod *nm = _code_roots.pop();
1020 if (nm != NULL) {
1021 NMethodMigrationOopClosure oop_cl(g1h, hr(), nm);
1022 nm->oops_do(&oop_cl);
1023 if (oop_cl.retain()) {
1024 to_be_retained.push(nm);
1025 }
1026 }
1027 }
1029 // Now push any code roots we need to retain
1030 assert(to_be_retained.is_empty() || hr()->evacuation_failed(),
1031 "Retained nmethod list must be empty or "
1032 "evacuation of this region failed");
1034 while (to_be_retained.is_nonempty()) {
1035 nmethod* nm = to_be_retained.pop();
1036 assert(nm != NULL, "sanity");
1037 add_strong_code_root(nm);
1038 }
1039 }
1041 void HeapRegionRemSet::strong_code_roots_do(CodeBlobClosure* blk) const {
1042 _code_roots.nmethods_do(blk);
1043 }
1045 size_t HeapRegionRemSet::strong_code_roots_mem_size() {
1046 return _code_roots.mem_size();
1047 }
1049 //-------------------- Iteration --------------------
1051 HeapRegionRemSetIterator:: HeapRegionRemSetIterator(HeapRegionRemSet* hrrs) :
1052 _hrrs(hrrs),
1053 _g1h(G1CollectedHeap::heap()),
1054 _coarse_map(&hrrs->_other_regions._coarse_map),
1055 _fine_grain_regions(hrrs->_other_regions._fine_grain_regions),
1056 _bosa(hrrs->bosa()),
1057 _is(Sparse),
1058 // Set these values so that we increment to the first region.
1059 _coarse_cur_region_index(-1),
1060 _coarse_cur_region_cur_card(HeapRegion::CardsPerRegion-1),
1061 _cur_region_cur_card(0),
1062 _fine_array_index(-1),
1063 _fine_cur_prt(NULL),
1064 _n_yielded_coarse(0),
1065 _n_yielded_fine(0),
1066 _n_yielded_sparse(0),
1067 _sparse_iter(&hrrs->_other_regions._sparse_table) {}
1069 bool HeapRegionRemSetIterator::coarse_has_next(size_t& card_index) {
1070 if (_hrrs->_other_regions._n_coarse_entries == 0) return false;
1071 // Go to the next card.
1072 _coarse_cur_region_cur_card++;
1073 // Was the last the last card in the current region?
1074 if (_coarse_cur_region_cur_card == HeapRegion::CardsPerRegion) {
1075 // Yes: find the next region. This may leave _coarse_cur_region_index
1076 // Set to the last index, in which case there are no more coarse
1077 // regions.
1078 _coarse_cur_region_index =
1079 (int) _coarse_map->get_next_one_offset(_coarse_cur_region_index + 1);
1080 if ((size_t)_coarse_cur_region_index < _coarse_map->size()) {
1081 _coarse_cur_region_cur_card = 0;
1082 HeapWord* r_bot =
1083 _g1h->region_at((uint) _coarse_cur_region_index)->bottom();
1084 _cur_region_card_offset = _bosa->index_for(r_bot);
1085 } else {
1086 return false;
1087 }
1088 }
1089 // If we didn't return false above, then we can yield a card.
1090 card_index = _cur_region_card_offset + _coarse_cur_region_cur_card;
1091 return true;
1092 }
1094 void HeapRegionRemSetIterator::fine_find_next_non_null_prt() {
1095 // Otherwise, find the next bucket list in the array.
1096 _fine_array_index++;
1097 while (_fine_array_index < (int) OtherRegionsTable::_max_fine_entries) {
1098 _fine_cur_prt = _fine_grain_regions[_fine_array_index];
1099 if (_fine_cur_prt != NULL) return;
1100 else _fine_array_index++;
1101 }
1102 assert(_fine_cur_prt == NULL, "Loop post");
1103 }
1105 bool HeapRegionRemSetIterator::fine_has_next(size_t& card_index) {
1106 if (fine_has_next()) {
1107 _cur_region_cur_card =
1108 _fine_cur_prt->_bm.get_next_one_offset(_cur_region_cur_card + 1);
1109 }
1110 while (!fine_has_next()) {
1111 if (_cur_region_cur_card == (size_t) HeapRegion::CardsPerRegion) {
1112 _cur_region_cur_card = 0;
1113 _fine_cur_prt = _fine_cur_prt->collision_list_next();
1114 }
1115 if (_fine_cur_prt == NULL) {
1116 fine_find_next_non_null_prt();
1117 if (_fine_cur_prt == NULL) return false;
1118 }
1119 assert(_fine_cur_prt != NULL && _cur_region_cur_card == 0,
1120 "inv.");
1121 HeapWord* r_bot =
1122 _fine_cur_prt->hr()->bottom();
1123 _cur_region_card_offset = _bosa->index_for(r_bot);
1124 _cur_region_cur_card = _fine_cur_prt->_bm.get_next_one_offset(0);
1125 }
1126 assert(fine_has_next(), "Or else we exited the loop via the return.");
1127 card_index = _cur_region_card_offset + _cur_region_cur_card;
1128 return true;
1129 }
1131 bool HeapRegionRemSetIterator::fine_has_next() {
1132 return
1133 _fine_cur_prt != NULL &&
1134 _cur_region_cur_card < HeapRegion::CardsPerRegion;
1135 }
1137 bool HeapRegionRemSetIterator::has_next(size_t& card_index) {
1138 switch (_is) {
1139 case Sparse:
1140 if (_sparse_iter.has_next(card_index)) {
1141 _n_yielded_sparse++;
1142 return true;
1143 }
1144 // Otherwise, deliberate fall-through
1145 _is = Fine;
1146 case Fine:
1147 if (fine_has_next(card_index)) {
1148 _n_yielded_fine++;
1149 return true;
1150 }
1151 // Otherwise, deliberate fall-through
1152 _is = Coarse;
1153 case Coarse:
1154 if (coarse_has_next(card_index)) {
1155 _n_yielded_coarse++;
1156 return true;
1157 }
1158 // Otherwise...
1159 break;
1160 }
1161 assert(ParallelGCThreads > 1 ||
1162 n_yielded() == _hrrs->occupied(),
1163 "Should have yielded all the cards in the rem set "
1164 "(in the non-par case).");
1165 return false;
1166 }
1170 OopOrNarrowOopStar* HeapRegionRemSet::_recorded_oops = NULL;
1171 HeapWord** HeapRegionRemSet::_recorded_cards = NULL;
1172 HeapRegion** HeapRegionRemSet::_recorded_regions = NULL;
1173 int HeapRegionRemSet::_n_recorded = 0;
1175 HeapRegionRemSet::Event* HeapRegionRemSet::_recorded_events = NULL;
1176 int* HeapRegionRemSet::_recorded_event_index = NULL;
1177 int HeapRegionRemSet::_n_recorded_events = 0;
1179 void HeapRegionRemSet::record(HeapRegion* hr, OopOrNarrowOopStar f) {
1180 if (_recorded_oops == NULL) {
1181 assert(_n_recorded == 0
1182 && _recorded_cards == NULL
1183 && _recorded_regions == NULL,
1184 "Inv");
1185 _recorded_oops = NEW_C_HEAP_ARRAY(OopOrNarrowOopStar, MaxRecorded, mtGC);
1186 _recorded_cards = NEW_C_HEAP_ARRAY(HeapWord*, MaxRecorded, mtGC);
1187 _recorded_regions = NEW_C_HEAP_ARRAY(HeapRegion*, MaxRecorded, mtGC);
1188 }
1189 if (_n_recorded == MaxRecorded) {
1190 gclog_or_tty->print_cr("Filled up 'recorded' (%d).", MaxRecorded);
1191 } else {
1192 _recorded_cards[_n_recorded] =
1193 (HeapWord*)align_size_down(uintptr_t(f),
1194 CardTableModRefBS::card_size);
1195 _recorded_oops[_n_recorded] = f;
1196 _recorded_regions[_n_recorded] = hr;
1197 _n_recorded++;
1198 }
1199 }
1201 void HeapRegionRemSet::record_event(Event evnt) {
1202 if (!G1RecordHRRSEvents) return;
1204 if (_recorded_events == NULL) {
1205 assert(_n_recorded_events == 0
1206 && _recorded_event_index == NULL,
1207 "Inv");
1208 _recorded_events = NEW_C_HEAP_ARRAY(Event, MaxRecordedEvents, mtGC);
1209 _recorded_event_index = NEW_C_HEAP_ARRAY(int, MaxRecordedEvents, mtGC);
1210 }
1211 if (_n_recorded_events == MaxRecordedEvents) {
1212 gclog_or_tty->print_cr("Filled up 'recorded_events' (%d).", MaxRecordedEvents);
1213 } else {
1214 _recorded_events[_n_recorded_events] = evnt;
1215 _recorded_event_index[_n_recorded_events] = _n_recorded;
1216 _n_recorded_events++;
1217 }
1218 }
1220 void HeapRegionRemSet::print_event(outputStream* str, Event evnt) {
1221 switch (evnt) {
1222 case Event_EvacStart:
1223 str->print("Evac Start");
1224 break;
1225 case Event_EvacEnd:
1226 str->print("Evac End");
1227 break;
1228 case Event_RSUpdateEnd:
1229 str->print("RS Update End");
1230 break;
1231 }
1232 }
1234 void HeapRegionRemSet::print_recorded() {
1235 int cur_evnt = 0;
1236 Event cur_evnt_kind;
1237 int cur_evnt_ind = 0;
1238 if (_n_recorded_events > 0) {
1239 cur_evnt_kind = _recorded_events[cur_evnt];
1240 cur_evnt_ind = _recorded_event_index[cur_evnt];
1241 }
1243 for (int i = 0; i < _n_recorded; i++) {
1244 while (cur_evnt < _n_recorded_events && i == cur_evnt_ind) {
1245 gclog_or_tty->print("Event: ");
1246 print_event(gclog_or_tty, cur_evnt_kind);
1247 gclog_or_tty->print_cr("");
1248 cur_evnt++;
1249 if (cur_evnt < MaxRecordedEvents) {
1250 cur_evnt_kind = _recorded_events[cur_evnt];
1251 cur_evnt_ind = _recorded_event_index[cur_evnt];
1252 }
1253 }
1254 gclog_or_tty->print("Added card " PTR_FORMAT " to region [" PTR_FORMAT "...]"
1255 " for ref " PTR_FORMAT ".\n",
1256 _recorded_cards[i], _recorded_regions[i]->bottom(),
1257 _recorded_oops[i]);
1258 }
1259 }
1261 void HeapRegionRemSet::reset_for_cleanup_tasks() {
1262 SparsePRT::reset_for_cleanup_tasks();
1263 }
1265 void HeapRegionRemSet::do_cleanup_work(HRRSCleanupTask* hrrs_cleanup_task) {
1266 _other_regions.do_cleanup_work(hrrs_cleanup_task);
1267 }
1269 void
1270 HeapRegionRemSet::finish_cleanup_task(HRRSCleanupTask* hrrs_cleanup_task) {
1271 SparsePRT::finish_cleanup_task(hrrs_cleanup_task);
1272 }
1274 #ifndef PRODUCT
1275 void PerRegionTable::test_fl_mem_size() {
1276 PerRegionTable* dummy = alloc(NULL);
1277 free(dummy);
1278 guarantee(dummy->mem_size() == fl_mem_size(), "fl_mem_size() does not return the correct element size");
1279 // try to reset the state
1280 _free_list = NULL;
1281 delete dummy;
1282 }
1284 void HeapRegionRemSet::test_prt() {
1285 PerRegionTable::test_fl_mem_size();
1286 }
1288 void HeapRegionRemSet::test() {
1289 os::sleep(Thread::current(), (jlong)5000, false);
1290 G1CollectedHeap* g1h = G1CollectedHeap::heap();
1292 // Run with "-XX:G1LogRSetRegionEntries=2", so that 1 and 5 end up in same
1293 // hash bucket.
1294 HeapRegion* hr0 = g1h->region_at(0);
1295 HeapRegion* hr1 = g1h->region_at(1);
1296 HeapRegion* hr2 = g1h->region_at(5);
1297 HeapRegion* hr3 = g1h->region_at(6);
1298 HeapRegion* hr4 = g1h->region_at(7);
1299 HeapRegion* hr5 = g1h->region_at(8);
1301 HeapWord* hr1_start = hr1->bottom();
1302 HeapWord* hr1_mid = hr1_start + HeapRegion::GrainWords/2;
1303 HeapWord* hr1_last = hr1->end() - 1;
1305 HeapWord* hr2_start = hr2->bottom();
1306 HeapWord* hr2_mid = hr2_start + HeapRegion::GrainWords/2;
1307 HeapWord* hr2_last = hr2->end() - 1;
1309 HeapWord* hr3_start = hr3->bottom();
1310 HeapWord* hr3_mid = hr3_start + HeapRegion::GrainWords/2;
1311 HeapWord* hr3_last = hr3->end() - 1;
1313 HeapRegionRemSet* hrrs = hr0->rem_set();
1315 // Make three references from region 0x101...
1316 hrrs->add_reference((OopOrNarrowOopStar)hr1_start);
1317 hrrs->add_reference((OopOrNarrowOopStar)hr1_mid);
1318 hrrs->add_reference((OopOrNarrowOopStar)hr1_last);
1320 hrrs->add_reference((OopOrNarrowOopStar)hr2_start);
1321 hrrs->add_reference((OopOrNarrowOopStar)hr2_mid);
1322 hrrs->add_reference((OopOrNarrowOopStar)hr2_last);
1324 hrrs->add_reference((OopOrNarrowOopStar)hr3_start);
1325 hrrs->add_reference((OopOrNarrowOopStar)hr3_mid);
1326 hrrs->add_reference((OopOrNarrowOopStar)hr3_last);
1328 // Now cause a coarsening.
1329 hrrs->add_reference((OopOrNarrowOopStar)hr4->bottom());
1330 hrrs->add_reference((OopOrNarrowOopStar)hr5->bottom());
1332 // Now, does iteration yield these three?
1333 HeapRegionRemSetIterator iter(hrrs);
1334 size_t sum = 0;
1335 size_t card_index;
1336 while (iter.has_next(card_index)) {
1337 HeapWord* card_start =
1338 G1CollectedHeap::heap()->bot_shared()->address_for_index(card_index);
1339 gclog_or_tty->print_cr(" Card " PTR_FORMAT ".", card_start);
1340 sum++;
1341 }
1342 guarantee(sum == 11 - 3 + 2048, "Failure");
1343 guarantee(sum == hrrs->occupied(), "Failure");
1344 }
1345 #endif