1 /*
2 * Copyright (c) 2014, 2019, 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_GC_G1_G1REGIONTOSPACEMAPPER_HPP
26 #define SHARE_GC_G1_G1REGIONTOSPACEMAPPER_HPP
27
28 #include "gc/g1/g1MemoryNodeManager.hpp"
29 #include "gc/g1/g1PageBasedVirtualSpace.hpp"
30 #include "memory/allocation.hpp"
31 #include "utilities/debug.hpp"
32
33 class WorkGang;
34
35 class G1MappingChangedListener {
36 public:
37 // Fired after commit of the memory, i.e. the memory this listener is registered
38 // for can be accessed.
39 // Zero_filled indicates that the memory can be considered as filled with zero bytes
40 // when called.
41 virtual void on_commit(uint start_idx, size_t num_regions, bool zero_filled) = 0;
42 };
43
44 // Maps region based commit/uncommit requests to the underlying page sized virtual
45 // space.
46 class G1RegionToSpaceMapper : public CHeapObj<mtGC> {
47 private:
48 G1MappingChangedListener* _listener;
49 protected:
50 // Backing storage.
51 G1PageBasedVirtualSpace _storage;
52
53 size_t _region_granularity;
54 // Mapping management
55 CHeapBitMap _commit_map;
56
57 G1RegionToSpaceMapper(ReservedSpace rs, size_t used_size, size_t page_size, size_t region_granularity, size_t commit_factor, MemoryType type);
58
59 void fire_on_commit(uint start_idx, size_t num_regions, bool zero_filled);
60 public:
61 MemRegion reserved() { return _storage.reserved(); }
62
63 size_t reserved_size() { return _storage.reserved_size(); }
64 size_t committed_size() { return _storage.committed_size(); }
65
66 void set_mapping_changed_listener(G1MappingChangedListener* listener) { _listener = listener; }
67
68 virtual ~G1RegionToSpaceMapper() {}
69
70 bool is_committed(uintptr_t idx) const {
71 return _commit_map.at(idx);
72 }
73
74 void commit_and_set_special();
75 virtual void commit_regions(uint start_idx, size_t num_regions = 1, WorkGang* pretouch_workers = NULL) = 0;
76 virtual void uncommit_regions(uint start_idx, size_t num_regions = 1) = 0;
77
78 // Creates an appropriate G1RegionToSpaceMapper for the given parameters.
79 // The actual space to be used within the given reservation is given by actual_size.
80 // This is because some OSes need to round up the reservation size to guarantee
81 // alignment of page_size.
82 // The byte_translation_factor defines how many bytes in a region correspond to
83 // a single byte in the data structure this mapper is for.
84 // Eg. in the card table, this value corresponds to the size a single card
85 // table entry corresponds to in the heap.
86 static G1RegionToSpaceMapper* create_mapper(ReservedSpace rs,
87 size_t actual_size,
88 size_t page_size,
89 size_t region_granularity,
90 size_t byte_translation_factor,
91 MemoryType type);
92
93 static G1RegionToSpaceMapper* create_heap_mapper(ReservedSpace rs,
94 size_t actual_size,
95 size_t page_size,
96 size_t region_granularity,
97 size_t byte_translation_factor,
98 MemoryType type);
99 };
100
101 // G1RegionToSpaceMapper implementation where
102 // part of space is mapped to dram and part to nv-dimm
103 class G1RegionToHeteroSpaceMapper : public G1RegionToSpaceMapper {
104 private:
105 ReservedSpace _rs;
106 G1RegionToSpaceMapper* _dram_mapper;
107 uint _num_committed_dram;
108 uint _num_committed_nvdimm;
109 uint _start_index_of_dram;
110 size_t _page_size;
111 size_t _commit_factor;
112 MemoryType _type;
113
114 public:
115 G1RegionToHeteroSpaceMapper(ReservedSpace rs, size_t used_size, size_t page_size, size_t region_granularity, size_t commit_factor, MemoryType type);
116 bool initialize();
117 uint num_committed_dram() const;
118 uint num_committed_nvdimm() const;
119
120 virtual void commit_regions(uint start_idx, size_t num_regions = 1, WorkGang* pretouch_workers = NULL);
121 virtual void uncommit_regions(uint start_idx, size_t num_regions = 1);
122 };
123 #endif // SHARE_GC_G1_G1REGIONTOSPACEMAPPER_HPP