1 /*
2 * Copyright (c) 2016, 2020, Red Hat, 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 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_GC_SHENANDOAH_SHENANDOAHCOLLECTIONSET_HPP
26 #define SHARE_GC_SHENANDOAH_SHENANDOAHCOLLECTIONSET_HPP
27
28 #include "memory/allocation.hpp"
29 #include "memory/virtualspace.hpp"
30 #include "gc/shenandoah/shenandoahHeap.hpp"
31 #include "gc/shenandoah/shenandoahHeapRegion.hpp"
32 #include "gc/shenandoah/shenandoahPadding.hpp"
33
34 class ShenandoahCollectionSet : public CHeapObj<mtGC> {
35 friend class ShenandoahHeap;
36 private:
37 size_t const _map_size;
38 size_t const _region_size_bytes_shift;
39 ReservedSpace _map_space;
40 char* const _cset_map;
41 // Bias cset map's base address for fast test if an oop is in cset
42 char* const _biased_cset_map;
43
44 ShenandoahHeap* const _heap;
45
46 size_t _garbage;
47 size_t _used;
48 size_t _region_count;
49
50 shenandoah_padding(0);
51 volatile size_t _current_index;
52 shenandoah_padding(1);
53
54 public:
55 ShenandoahCollectionSet(ShenandoahHeap* heap, ReservedSpace space, char* heap_base);
56
57 // Add region to collection set
58 void add_region(ShenandoahHeapRegion* r);
59
60 // MT version
61 ShenandoahHeapRegion* claim_next();
62
63 // Single-thread version
64 ShenandoahHeapRegion* next();
65
66 size_t count() const { return _region_count; }
67 bool is_empty() const { return _region_count == 0; }
68
69 void clear_current_index() {
70 _current_index = 0;
71 }
72
73 inline bool is_in(ShenandoahHeapRegion* r) const;
74 inline bool is_in(size_t region_idx) const;
75 inline bool is_in(oop obj) const;
76 inline bool is_in_loc(void* loc) const;
77
78 void print_on(outputStream* out) const;
79
80 size_t used() const { return _used; }
81 size_t garbage() const { return _garbage; }
82 void clear();
83
84 private:
85 char* map_address() const {
86 return _cset_map;
87 }
88 char* biased_map_address() const {
89 return _biased_cset_map;
90 }
91 };
92
93 #endif // SHARE_GC_SHENANDOAH_SHENANDOAHCOLLECTIONSET_HPP