Tue, 26 Jan 2010 16:52:29 -0800
6920090: G1: Disable ReduceInitialCardMarks at least until 6920109 is fixed
Summary: G1 now answers "no" to the query can_elide_initializing_store_barrier() in the product build. A debug flag allows alternate behaviour in debug builds.
Reviewed-by: iveresov, tonyp
1 /*
2 * Copyright 2001-2009 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/_sparsePRT.cpp.incl"
28 #define SPARSE_PRT_VERBOSE 0
30 #define UNROLL_CARD_LOOPS 1
32 void SparsePRT::init_iterator(SparsePRTIter* sprt_iter) {
33 sprt_iter->init(this);
34 }
36 void SparsePRTEntry::init(RegionIdx_t region_ind) {
37 _region_ind = region_ind;
38 _next_index = NullEntry;
39 #if UNROLL_CARD_LOOPS
40 assert(CardsPerEntry == 4, "Assumption. If changes, un-unroll.");
41 _cards[0] = NullEntry;
42 _cards[1] = NullEntry;
43 _cards[2] = NullEntry;
44 _cards[3] = NullEntry;
45 #else
46 for (int i = 0; i < CardsPerEntry; i++)
47 _cards[i] = NullEntry;
48 #endif
49 }
51 bool SparsePRTEntry::contains_card(CardIdx_t card_index) const {
52 #if UNROLL_CARD_LOOPS
53 assert(CardsPerEntry == 4, "Assumption. If changes, un-unroll.");
54 if (_cards[0] == card_index) return true;
55 if (_cards[1] == card_index) return true;
56 if (_cards[2] == card_index) return true;
57 if (_cards[3] == card_index) return true;
58 #else
59 for (int i = 0; i < CardsPerEntry; i++) {
60 if (_cards[i] == card_index) return true;
61 }
62 #endif
63 // Otherwise, we're full.
64 return false;
65 }
67 int SparsePRTEntry::num_valid_cards() const {
68 int sum = 0;
69 #if UNROLL_CARD_LOOPS
70 assert(CardsPerEntry == 4, "Assumption. If changes, un-unroll.");
71 if (_cards[0] != NullEntry) sum++;
72 if (_cards[1] != NullEntry) sum++;
73 if (_cards[2] != NullEntry) sum++;
74 if (_cards[3] != NullEntry) sum++;
75 #else
76 for (int i = 0; i < CardsPerEntry; i++) {
77 if (_cards[i] != NulLEntry) sum++;
78 }
79 #endif
80 // Otherwise, we're full.
81 return sum;
82 }
84 SparsePRTEntry::AddCardResult SparsePRTEntry::add_card(CardIdx_t card_index) {
85 #if UNROLL_CARD_LOOPS
86 assert(CardsPerEntry == 4, "Assumption. If changes, un-unroll.");
87 CardIdx_t c = _cards[0];
88 if (c == card_index) return found;
89 if (c == NullEntry) { _cards[0] = card_index; return added; }
90 c = _cards[1];
91 if (c == card_index) return found;
92 if (c == NullEntry) { _cards[1] = card_index; return added; }
93 c = _cards[2];
94 if (c == card_index) return found;
95 if (c == NullEntry) { _cards[2] = card_index; return added; }
96 c = _cards[3];
97 if (c == card_index) return found;
98 if (c == NullEntry) { _cards[3] = card_index; return added; }
99 #else
100 for (int i = 0; i < CardsPerEntry; i++) {
101 CardIdx_t c = _cards[i];
102 if (c == card_index) return found;
103 if (c == NullEntry) {
104 _cards[i] = card_index;
105 return added;
106 }
107 }
108 #endif
109 // Otherwise, we're full.
110 return overflow;
111 }
113 void SparsePRTEntry::copy_cards(CardIdx_t* cards) const {
114 #if UNROLL_CARD_LOOPS
115 assert(CardsPerEntry == 4, "Assumption. If changes, un-unroll.");
116 cards[0] = _cards[0];
117 cards[1] = _cards[1];
118 cards[2] = _cards[2];
119 cards[3] = _cards[3];
120 #else
121 for (int i = 0; i < CardsPerEntry; i++) {
122 cards[i] = _cards[i];
123 }
124 #endif
125 }
127 void SparsePRTEntry::copy_cards(SparsePRTEntry* e) const {
128 copy_cards(&e->_cards[0]);
129 }
131 // ----------------------------------------------------------------------
133 RSHashTable::RSHashTable(size_t capacity) :
134 _capacity(capacity), _capacity_mask(capacity-1),
135 _occupied_entries(0), _occupied_cards(0),
136 _entries(NEW_C_HEAP_ARRAY(SparsePRTEntry, capacity)),
137 _buckets(NEW_C_HEAP_ARRAY(int, capacity)),
138 _free_list(NullEntry), _free_region(0)
139 {
140 clear();
141 }
143 RSHashTable::~RSHashTable() {
144 if (_entries != NULL) {
145 FREE_C_HEAP_ARRAY(SparsePRTEntry, _entries);
146 _entries = NULL;
147 }
148 if (_buckets != NULL) {
149 FREE_C_HEAP_ARRAY(int, _buckets);
150 _buckets = NULL;
151 }
152 }
154 void RSHashTable::clear() {
155 _occupied_entries = 0;
156 _occupied_cards = 0;
157 guarantee(_entries != NULL, "INV");
158 guarantee(_buckets != NULL, "INV");
160 guarantee(_capacity <= ((size_t)1 << (sizeof(int)*BitsPerByte-1)) - 1,
161 "_capacity too large");
163 // This will put -1 == NullEntry in the key field of all entries.
164 memset(_entries, -1, _capacity * sizeof(SparsePRTEntry));
165 memset(_buckets, -1, _capacity * sizeof(int));
166 _free_list = NullEntry;
167 _free_region = 0;
168 }
170 bool RSHashTable::add_card(RegionIdx_t region_ind, CardIdx_t card_index) {
171 SparsePRTEntry* e = entry_for_region_ind_create(region_ind);
172 assert(e != NULL && e->r_ind() == region_ind,
173 "Postcondition of call above.");
174 SparsePRTEntry::AddCardResult res = e->add_card(card_index);
175 if (res == SparsePRTEntry::added) _occupied_cards++;
176 #if SPARSE_PRT_VERBOSE
177 gclog_or_tty->print_cr(" after add_card[%d]: valid-cards = %d.",
178 pointer_delta(e, _entries, sizeof(SparsePRTEntry)),
179 e->num_valid_cards());
180 #endif
181 assert(e->num_valid_cards() > 0, "Postcondition");
182 return res != SparsePRTEntry::overflow;
183 }
185 bool RSHashTable::get_cards(RegionIdx_t region_ind, CardIdx_t* cards) {
186 int ind = (int) (region_ind & capacity_mask());
187 int cur_ind = _buckets[ind];
188 SparsePRTEntry* cur;
189 while (cur_ind != NullEntry &&
190 (cur = entry(cur_ind))->r_ind() != region_ind) {
191 cur_ind = cur->next_index();
192 }
194 if (cur_ind == NullEntry) return false;
195 // Otherwise...
196 assert(cur->r_ind() == region_ind, "Postcondition of loop + test above.");
197 assert(cur->num_valid_cards() > 0, "Inv");
198 cur->copy_cards(cards);
199 return true;
200 }
202 bool RSHashTable::delete_entry(RegionIdx_t region_ind) {
203 int ind = (int) (region_ind & capacity_mask());
204 int* prev_loc = &_buckets[ind];
205 int cur_ind = *prev_loc;
206 SparsePRTEntry* cur;
207 while (cur_ind != NullEntry &&
208 (cur = entry(cur_ind))->r_ind() != region_ind) {
209 prev_loc = cur->next_index_addr();
210 cur_ind = *prev_loc;
211 }
213 if (cur_ind == NullEntry) return false;
214 // Otherwise, splice out "cur".
215 *prev_loc = cur->next_index();
216 _occupied_cards -= cur->num_valid_cards();
217 free_entry(cur_ind);
218 _occupied_entries--;
219 return true;
220 }
222 SparsePRTEntry*
223 RSHashTable::entry_for_region_ind(RegionIdx_t region_ind) const {
224 assert(occupied_entries() < capacity(), "Precondition");
225 int ind = (int) (region_ind & capacity_mask());
226 int cur_ind = _buckets[ind];
227 SparsePRTEntry* cur;
228 // XXX
229 // int k = 0;
230 while (cur_ind != NullEntry &&
231 (cur = entry(cur_ind))->r_ind() != region_ind) {
232 /*
233 k++;
234 if (k > 10) {
235 gclog_or_tty->print_cr("RSHashTable::entry_for_region_ind(%d): "
236 "k = %d, cur_ind = %d.", region_ind, k, cur_ind);
237 if (k >= 1000) {
238 while (1) ;
239 }
240 }
241 */
242 cur_ind = cur->next_index();
243 }
245 if (cur_ind != NullEntry) {
246 assert(cur->r_ind() == region_ind, "Loop postcondition + test");
247 return cur;
248 } else {
249 return NULL;
250 }
251 }
253 SparsePRTEntry*
254 RSHashTable::entry_for_region_ind_create(RegionIdx_t region_ind) {
255 SparsePRTEntry* res = entry_for_region_ind(region_ind);
256 if (res == NULL) {
257 int new_ind = alloc_entry();
258 assert(0 <= new_ind && (size_t)new_ind < capacity(), "There should be room.");
259 res = entry(new_ind);
260 res->init(region_ind);
261 // Insert at front.
262 int ind = (int) (region_ind & capacity_mask());
263 res->set_next_index(_buckets[ind]);
264 _buckets[ind] = new_ind;
265 _occupied_entries++;
266 }
267 return res;
268 }
270 int RSHashTable::alloc_entry() {
271 int res;
272 if (_free_list != NullEntry) {
273 res = _free_list;
274 _free_list = entry(res)->next_index();
275 return res;
276 } else if ((size_t) _free_region+1 < capacity()) {
277 res = _free_region;
278 _free_region++;
279 return res;
280 } else {
281 return NullEntry;
282 }
283 }
285 void RSHashTable::free_entry(int fi) {
286 entry(fi)->set_next_index(_free_list);
287 _free_list = fi;
288 }
290 void RSHashTable::add_entry(SparsePRTEntry* e) {
291 assert(e->num_valid_cards() > 0, "Precondition.");
292 SparsePRTEntry* e2 = entry_for_region_ind_create(e->r_ind());
293 e->copy_cards(e2);
294 _occupied_cards += e2->num_valid_cards();
295 assert(e2->num_valid_cards() > 0, "Postcondition.");
296 }
298 CardIdx_t /* RSHashTable:: */ RSHashTableIter::find_first_card_in_list() {
299 CardIdx_t res;
300 while (_bl_ind != RSHashTable::NullEntry) {
301 res = _rsht->entry(_bl_ind)->card(0);
302 if (res != SparsePRTEntry::NullEntry) {
303 return res;
304 } else {
305 _bl_ind = _rsht->entry(_bl_ind)->next_index();
306 }
307 }
308 // Otherwise, none found:
309 return SparsePRTEntry::NullEntry;
310 }
312 size_t /* RSHashTable:: */ RSHashTableIter::compute_card_ind(CardIdx_t ci) {
313 return
314 _heap_bot_card_ind
315 + (_rsht->entry(_bl_ind)->r_ind() * HeapRegion::CardsPerRegion)
316 + ci;
317 }
319 bool /* RSHashTable:: */ RSHashTableIter::has_next(size_t& card_index) {
320 _card_ind++;
321 CardIdx_t ci;
322 if (_card_ind < SparsePRTEntry::CardsPerEntry &&
323 ((ci = _rsht->entry(_bl_ind)->card(_card_ind)) !=
324 SparsePRTEntry::NullEntry)) {
325 card_index = compute_card_ind(ci);
326 return true;
327 }
328 // Otherwise, must find the next valid entry.
329 _card_ind = 0;
331 if (_bl_ind != RSHashTable::NullEntry) {
332 _bl_ind = _rsht->entry(_bl_ind)->next_index();
333 ci = find_first_card_in_list();
334 if (ci != SparsePRTEntry::NullEntry) {
335 card_index = compute_card_ind(ci);
336 return true;
337 }
338 }
339 // If we didn't return above, must go to the next non-null table index.
340 _tbl_ind++;
341 while ((size_t)_tbl_ind < _rsht->capacity()) {
342 _bl_ind = _rsht->_buckets[_tbl_ind];
343 ci = find_first_card_in_list();
344 if (ci != SparsePRTEntry::NullEntry) {
345 card_index = compute_card_ind(ci);
346 return true;
347 }
348 // Otherwise, try next entry.
349 _tbl_ind++;
350 }
351 // Otherwise, there were no entry.
352 return false;
353 }
355 bool RSHashTable::contains_card(RegionIdx_t region_index, CardIdx_t card_index) const {
356 SparsePRTEntry* e = entry_for_region_ind(region_index);
357 return (e != NULL && e->contains_card(card_index));
358 }
360 size_t RSHashTable::mem_size() const {
361 return sizeof(this) +
362 capacity() * (sizeof(SparsePRTEntry) + sizeof(int));
363 }
365 // ----------------------------------------------------------------------
367 SparsePRT* SparsePRT::_head_expanded_list = NULL;
369 void SparsePRT::add_to_expanded_list(SparsePRT* sprt) {
370 // We could expand multiple times in a pause -- only put on list once.
371 if (sprt->expanded()) return;
372 sprt->set_expanded(true);
373 SparsePRT* hd = _head_expanded_list;
374 while (true) {
375 sprt->_next_expanded = hd;
376 SparsePRT* res =
377 (SparsePRT*)
378 Atomic::cmpxchg_ptr(sprt, &_head_expanded_list, hd);
379 if (res == hd) return;
380 else hd = res;
381 }
382 }
385 SparsePRT* SparsePRT::get_from_expanded_list() {
386 SparsePRT* hd = _head_expanded_list;
387 while (hd != NULL) {
388 SparsePRT* next = hd->next_expanded();
389 SparsePRT* res =
390 (SparsePRT*)
391 Atomic::cmpxchg_ptr(next, &_head_expanded_list, hd);
392 if (res == hd) {
393 hd->set_next_expanded(NULL);
394 return hd;
395 } else {
396 hd = res;
397 }
398 }
399 return NULL;
400 }
403 void SparsePRT::cleanup_all() {
404 // First clean up all expanded tables so they agree on next and cur.
405 SparsePRT* sprt = get_from_expanded_list();
406 while (sprt != NULL) {
407 sprt->cleanup();
408 sprt = get_from_expanded_list();
409 }
410 }
413 SparsePRT::SparsePRT(HeapRegion* hr) :
414 _expanded(false), _next_expanded(NULL)
415 {
416 _cur = new RSHashTable(InitialCapacity);
417 _next = _cur;
418 }
421 SparsePRT::~SparsePRT() {
422 assert(_next != NULL && _cur != NULL, "Inv");
423 if (_cur != _next) { delete _cur; }
424 delete _next;
425 }
428 size_t SparsePRT::mem_size() const {
429 // We ignore "_cur" here, because it either = _next, or else it is
430 // on the deleted list.
431 return sizeof(this) + _next->mem_size();
432 }
434 bool SparsePRT::add_card(RegionIdx_t region_id, CardIdx_t card_index) {
435 #if SPARSE_PRT_VERBOSE
436 gclog_or_tty->print_cr(" Adding card %d from region %d to region %d sparse.",
437 card_index, region_id, _hr->hrs_index());
438 #endif
439 if (_next->occupied_entries() * 2 > _next->capacity()) {
440 expand();
441 }
442 return _next->add_card(region_id, card_index);
443 }
445 bool SparsePRT::get_cards(RegionIdx_t region_id, CardIdx_t* cards) {
446 return _next->get_cards(region_id, cards);
447 }
449 bool SparsePRT::delete_entry(RegionIdx_t region_id) {
450 return _next->delete_entry(region_id);
451 }
453 void SparsePRT::clear() {
454 // If they differ, _next is bigger then cur, so next has no chance of
455 // being the initial size.
456 if (_next != _cur) {
457 delete _next;
458 }
460 if (_cur->capacity() != InitialCapacity) {
461 delete _cur;
462 _cur = new RSHashTable(InitialCapacity);
463 } else {
464 _cur->clear();
465 }
466 _next = _cur;
467 }
469 void SparsePRT::cleanup() {
470 // Make sure that the current and next tables agree.
471 if (_cur != _next) {
472 delete _cur;
473 }
474 _cur = _next;
475 set_expanded(false);
476 }
478 void SparsePRT::expand() {
479 RSHashTable* last = _next;
480 _next = new RSHashTable(last->capacity() * 2);
482 #if SPARSE_PRT_VERBOSE
483 gclog_or_tty->print_cr(" Expanded sparse table for %d to %d.",
484 _hr->hrs_index(), _next->capacity());
485 #endif
486 for (size_t i = 0; i < last->capacity(); i++) {
487 SparsePRTEntry* e = last->entry((int)i);
488 if (e->valid_entry()) {
489 #if SPARSE_PRT_VERBOSE
490 gclog_or_tty->print_cr(" During expansion, transferred entry for %d.",
491 e->r_ind());
492 #endif
493 _next->add_entry(e);
494 }
495 }
496 if (last != _cur) {
497 delete last;
498 }
499 add_to_expanded_list(this);
500 }