1/*
2 * Copyright (c) 2013, 2018, Red Hat, Inc. All rights reserved.
3 *
4 * This code is free software; you can redistribute it and/or modify it
5 * under the terms of the GNU General Public License version 2 only, as
6 * published by the Free Software Foundation.
7 *
8 * This code is distributed in the hope that it will be useful, but WITHOUT
9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
11 * version 2 for more details (a copy is included in the LICENSE file that
12 * accompanied this code).
13 *
14 * You should have received a copy of the GNU General Public License version
15 * 2 along with this work; if not, write to the Free Software Foundation,
16 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
17 *
18 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
19 * or visit www.oracle.com if you need additional information or have any
20 * questions.
21 *
22 */
23
24#ifndef SHARE_GC_SHENANDOAH_SHENANDOAHHEAPREGIONSET_HPP
25#define SHARE_GC_SHENANDOAH_SHENANDOAHHEAPREGIONSET_HPP
26
27#include "memory/allocation.hpp"
28#include "gc/shenandoah/shenandoahHeap.hpp"
29#include "gc/shenandoah/shenandoahHeapRegion.hpp"
30
31class ShenandoahHeapRegionSet;
32
33class ShenandoahHeapRegionSetIterator : public StackObj {
34private:
35 const ShenandoahHeapRegionSet* _set;
36 ShenandoahHeap* const _heap;
37
38 DEFINE_PAD_MINUS_SIZE(0, DEFAULT_CACHE_LINE_SIZE, sizeof(volatile jint));
39 volatile jint _current_index;
40 DEFINE_PAD_MINUS_SIZE(1, DEFAULT_CACHE_LINE_SIZE, 0);
41
42 // No implicit copying: iterators should be passed by reference to capture the state
43 ShenandoahHeapRegionSetIterator(const ShenandoahHeapRegionSetIterator& that);
44 ShenandoahHeapRegionSetIterator& operator=(const ShenandoahHeapRegionSetIterator& o);
45
46public:
47 ShenandoahHeapRegionSetIterator(const ShenandoahHeapRegionSet* const set);
48
49 // Reset existing iterator to new set
50 void reset(const ShenandoahHeapRegionSet* const set);
51
52 // MT version
53 ShenandoahHeapRegion* claim_next();
54
55 // Single-thread version
56 ShenandoahHeapRegion* next();
57};
58
59class ShenandoahHeapRegionSet : public CHeapObj<mtGC> {
60 friend class ShenandoahHeap;
61private:
62 ShenandoahHeap* const _heap;
63 size_t const _map_size;
64 size_t const _region_size_bytes_shift;
65 jbyte* const _set_map;
66 // Bias set map's base address for fast test if an oop is in set
67 jbyte* const _biased_set_map;
68 size_t _region_count;
69
70public:
71 ShenandoahHeapRegionSet();
72 ~ShenandoahHeapRegionSet();
73
74 // Add region to set
75 void add_region(ShenandoahHeapRegion* r);
76 bool add_region_check_for_duplicates(ShenandoahHeapRegion* r);
77
78 // Remove region from set
79 void remove_region(ShenandoahHeapRegion* r);
80
81 size_t count() const { return _region_count; }
82 bool is_empty() const { return _region_count == 0; }
83
84 inline bool is_in(ShenandoahHeapRegion* r) const;
85 inline bool is_in(size_t region_number) const;
86 inline bool is_in(HeapWord* p) const;
87
88 void print_on(outputStream* out) const;
89
90 void clear();
91
92private:
93 jbyte* biased_map_address() const {
94 return _biased_set_map;
95 }
96};
97
98#endif // SHARE_GC_SHENANDOAH_SHENANDOAHHEAPREGIONSET_HPP
99