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