1/*
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3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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12 * version 2 for more details (a copy is included in the LICENSE file that
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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
32class WorkGang;
33
34class 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.
45class 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
102class G1RegionToHeteroSpaceMapper : public G1RegionToSpaceMapper {
103private:
104 ReservedSpace _rs;
105 G1RegionToSpaceMapper* _dram_mapper;
106 uint _num_committed_dram;
107 uint _num_committed_nvdimm;
108 uint _start_index_of_dram;
109 size_t _page_size;
110 size_t _commit_factor;
111 MemoryType _type;
112
113public:
114 G1RegionToHeteroSpaceMapper(ReservedSpace rs, size_t used_size, size_t page_size, size_t region_granularity, size_t commit_factor, MemoryType type);
115 bool initialize();
116 uint num_committed_dram() const;
117 uint num_committed_nvdimm() const;
118
119 virtual void commit_regions(uint start_idx, size_t num_regions = 1, WorkGang* pretouch_workers = NULL);
120 virtual void uncommit_regions(uint start_idx, size_t num_regions = 1);
121};
122#endif // SHARE_GC_G1_G1REGIONTOSPACEMAPPER_HPP
123