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 // Remembered set for a heap region. Represent a set of "cards" that
26 // contain pointers into the owner heap region. Cards are defined somewhat
27 // abstractly, in terms of what the "BlockOffsetTable" in use can parse.
28
29 class G1CollectedHeap;
30 class G1BlockOffsetSharedArray;
31 class HeapRegion;
32 class HeapRegionRemSetIterator;
33 class PosParPRT;
34 class SparsePRT;
35
36
37 // The "_coarse_map" is a bitmap with one bit for each region, where set
38 // bits indicate that the corresponding region may contain some pointer
39 // into the owning region.
40
41 // The "_fine_grain_entries" array is an open hash table of PerRegionTables
42 // (PRTs), indicating regions for which we're keeping the RS as a set of
43 // cards. The strategy is to cap the size of the fine-grain table,
44 // deleting an entry and setting the corresponding coarse-grained bit when
409 // sets "card_index" to one of those cards (which is then considered
410 // yielded.) Otherwise, returns false (and leaves "card_index"
411 // undefined.)
412 bool has_next(size_t& card_index);
413
414 size_t n_yielded_fine() { return _n_yielded_fine; }
415 size_t n_yielded_coarse() { return _n_yielded_coarse; }
416 size_t n_yielded_sparse() { return _n_yielded_sparse; }
417 size_t n_yielded() {
418 return n_yielded_fine() + n_yielded_coarse() + n_yielded_sparse();
419 }
420 };
421
422 #if 0
423 class CardClosure: public Closure {
424 public:
425 virtual void do_card(HeapWord* card_start) = 0;
426 };
427
428 #endif
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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_HEAPREGIONREMSET_HPP
26 #define SHARE_VM_GC_IMPLEMENTATION_G1_HEAPREGIONREMSET_HPP
27
28 #include "gc_implementation/g1/sparsePRT.hpp"
29
30 // Remembered set for a heap region. Represent a set of "cards" that
31 // contain pointers into the owner heap region. Cards are defined somewhat
32 // abstractly, in terms of what the "BlockOffsetTable" in use can parse.
33
34 class G1CollectedHeap;
35 class G1BlockOffsetSharedArray;
36 class HeapRegion;
37 class HeapRegionRemSetIterator;
38 class PosParPRT;
39 class SparsePRT;
40
41
42 // The "_coarse_map" is a bitmap with one bit for each region, where set
43 // bits indicate that the corresponding region may contain some pointer
44 // into the owning region.
45
46 // The "_fine_grain_entries" array is an open hash table of PerRegionTables
47 // (PRTs), indicating regions for which we're keeping the RS as a set of
48 // cards. The strategy is to cap the size of the fine-grain table,
49 // deleting an entry and setting the corresponding coarse-grained bit when
414 // sets "card_index" to one of those cards (which is then considered
415 // yielded.) Otherwise, returns false (and leaves "card_index"
416 // undefined.)
417 bool has_next(size_t& card_index);
418
419 size_t n_yielded_fine() { return _n_yielded_fine; }
420 size_t n_yielded_coarse() { return _n_yielded_coarse; }
421 size_t n_yielded_sparse() { return _n_yielded_sparse; }
422 size_t n_yielded() {
423 return n_yielded_fine() + n_yielded_coarse() + n_yielded_sparse();
424 }
425 };
426
427 #if 0
428 class CardClosure: public Closure {
429 public:
430 virtual void do_card(HeapWord* card_start) = 0;
431 };
432
433 #endif
434
435 #endif // SHARE_VM_GC_IMPLEMENTATION_G1_HEAPREGIONREMSET_HPP
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