1/*
2 * Copyright (c) 2016, 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_SHENANDOAHCOLLECTIONSET_HPP
25#define SHARE_GC_SHENANDOAH_SHENANDOAHCOLLECTIONSET_HPP
26
27#include "memory/allocation.hpp"
28#include "gc/shenandoah/shenandoahHeap.hpp"
29#include "gc/shenandoah/shenandoahHeapRegion.hpp"
30
31class ShenandoahCollectionSet : public CHeapObj<mtGC> {
32 friend class ShenandoahHeap;
33private:
34 size_t const _map_size;
35 size_t const _region_size_bytes_shift;
36 ReservedSpace _map_space;
37 char* const _cset_map;
38 // Bias cset map's base address for fast test if an oop is in cset
39 char* const _biased_cset_map;
40
41 ShenandoahHeap* const _heap;
42
43 size_t _garbage;
44 size_t _live_data;
45 size_t _used;
46 size_t _region_count;
47
48 DEFINE_PAD_MINUS_SIZE(0, DEFAULT_CACHE_LINE_SIZE, sizeof(volatile size_t));
49 volatile jint _current_index;
50 DEFINE_PAD_MINUS_SIZE(1, DEFAULT_CACHE_LINE_SIZE, 0);
51
52public:
53 ShenandoahCollectionSet(ShenandoahHeap* heap, char* heap_base, size_t size);
54
55 // Add region to collection set
56 void add_region(ShenandoahHeapRegion* r);
57 bool add_region_check_for_duplicates(ShenandoahHeapRegion* r);
58
59 // Bring per-region statuses to consistency with this collection.
60 // TODO: This is a transitional interface that bridges the gap between
61 // region statuses and this collection. Should go away after we merge them.
62 void update_region_status();
63
64 // Remove region from collection set
65 void remove_region(ShenandoahHeapRegion* r);
66
67 // MT version
68 ShenandoahHeapRegion* claim_next();
69
70 // Single-thread version
71 ShenandoahHeapRegion* next();
72
73 size_t count() const { return _region_count; }
74 bool is_empty() const { return _region_count == 0; }
75
76 void clear_current_index() {
77 _current_index = 0;
78 }
79
80 inline bool is_in(ShenandoahHeapRegion* r) const;
81 inline bool is_in(size_t region_number) const;
82 inline bool is_in(HeapWord* p) const;
83
84 void print_on(outputStream* out) const;
85
86 size_t used() const { return _used; }
87 size_t live_data() const { return _live_data; }
88 size_t garbage() const { return _garbage; }
89 void clear();
90
91private:
92 char* map_address() const {
93 return _cset_map;
94 }
95 char* biased_map_address() const {
96 return _biased_cset_map;
97 }
98};
99
100#endif // SHARE_GC_SHENANDOAH_SHENANDOAHCOLLECTIONSET_HPP
101