1 /*
2 * Copyright (c) 2001, 2009, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 // Sparse remembered set for a heap region (the "owning" region). Maps
26 // indices of other regions to short sequences of cards in the other region
27 // that might contain pointers into the owner region.
28
29 // These tables only expand while they are accessed in parallel --
30 // deletions may be done in single-threaded code. This allows us to allow
31 // unsynchronized reads/iterations, as long as expansions caused by
32 // insertions only enqueue old versions for deletions, but do not delete
33 // old versions synchronously.
34
35 class SparsePRTEntry: public CHeapObj {
36 public:
37 enum SomePublicConstants {
38 NullEntry = -1,
39 UnrollFactor = 4
40 };
41 private:
42 RegionIdx_t _region_ind;
43 int _next_index;
44 CardIdx_t _cards[1];
284 #if 0
285 void verify_is_cleared();
286 void print();
287 #endif
288 };
289
290
291 class SparsePRTIter: public /* RSHashTable:: */RSHashTableIter {
292 public:
293 SparsePRTIter(size_t heap_bot_card_ind) :
294 /* RSHashTable:: */RSHashTableIter(heap_bot_card_ind)
295 {}
296
297 void init(const SparsePRT* sprt) {
298 RSHashTableIter::init(sprt->cur());
299 }
300 bool has_next(size_t& card_index) {
301 return RSHashTableIter::has_next(card_index);
302 }
303 };
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1 /*
2 * Copyright (c) 2001, 2010, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #ifndef SHARE_VM_GC_IMPLEMENTATION_G1_SPARSEPRT_HPP
26 #define SHARE_VM_GC_IMPLEMENTATION_G1_SPARSEPRT_HPP
27
28 #include "gc_implementation/g1/g1CollectedHeap.inline.hpp"
29 #include "gc_implementation/g1/heapRegion.hpp"
30 #include "memory/allocation.hpp"
31 #include "memory/cardTableModRefBS.hpp"
32 #include "runtime/mutex.hpp"
33 #include "utilities/globalDefinitions.hpp"
34
35 // Sparse remembered set for a heap region (the "owning" region). Maps
36 // indices of other regions to short sequences of cards in the other region
37 // that might contain pointers into the owner region.
38
39 // These tables only expand while they are accessed in parallel --
40 // deletions may be done in single-threaded code. This allows us to allow
41 // unsynchronized reads/iterations, as long as expansions caused by
42 // insertions only enqueue old versions for deletions, but do not delete
43 // old versions synchronously.
44
45 class SparsePRTEntry: public CHeapObj {
46 public:
47 enum SomePublicConstants {
48 NullEntry = -1,
49 UnrollFactor = 4
50 };
51 private:
52 RegionIdx_t _region_ind;
53 int _next_index;
54 CardIdx_t _cards[1];
294 #if 0
295 void verify_is_cleared();
296 void print();
297 #endif
298 };
299
300
301 class SparsePRTIter: public /* RSHashTable:: */RSHashTableIter {
302 public:
303 SparsePRTIter(size_t heap_bot_card_ind) :
304 /* RSHashTable:: */RSHashTableIter(heap_bot_card_ind)
305 {}
306
307 void init(const SparsePRT* sprt) {
308 RSHashTableIter::init(sprt->cur());
309 }
310 bool has_next(size_t& card_index) {
311 return RSHashTableIter::has_next(card_index);
312 }
313 };
314
315 #endif // SHARE_VM_GC_IMPLEMENTATION_G1_SPARSEPRT_HPP
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