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24 #ifndef SHARE_VM_MEMORY_METASPACE_SHARED_HPP
25 #define SHARE_VM_MEMORY_METASPACE_SHARED_HPP
26 
27 #include "memory/allocation.hpp"
28 #include "memory/memRegion.hpp"
29 #include "runtime/virtualspace.hpp"
30 #include "utilities/exceptions.hpp"
31 #include "utilities/macros.hpp"
32 
33 #define LargeSharedArchiveSize    (300*M)
34 #define HugeSharedArchiveSize     (800*M)
35 #define ReadOnlyRegionPercentage  0.39
36 #define ReadWriteRegionPercentage 0.50
37 #define MiscDataRegionPercentage  0.09
38 #define MiscCodeRegionPercentage  0.02
39 #define LargeThresholdClassCount  5000
40 #define HugeThresholdClassCount   40000
41 
42 #define SET_ESTIMATED_SIZE(type, region)                              \
43   Shared ##region## Size  = FLAG_IS_DEFAULT(Shared ##region## Size) ? \
44     (uintx)(type ## SharedArchiveSize *  region ## RegionPercentage) : Shared ## region ## Size
45 
46 class FileMapInfo;
47 
48 // Class Data Sharing Support
49 class MetaspaceShared : AllStatic {
50 
51   // CDS support
52   static ReservedSpace* _shared_rs;
53   static int _max_alignment;
54   static bool _link_classes_made_progress;
55   static bool _check_classes_made_progress;
56   static bool _has_error_classes;
57   static bool _archive_loading_failed;
58   static bool _remapped_readwrite;
59  public:
60   enum {
61     vtbl_list_size         = 17,   // number of entries in the shared space vtable list.
62     num_virtuals           = 200,  // maximum number of virtual functions
63                                    // If virtual functions are added to Metadata,
64                                    // this number needs to be increased.  Also,
65                                    // SharedMiscCodeSize will need to be increased.
66                                    // The following 2 sizes were based on
67                                    // MetaspaceShared::generate_vtable_methods()
68     vtbl_method_size       = 16,   // conservative size of the mov1 and jmp instructions
69                                    // for the x64 platform
70     vtbl_common_code_size  = (1*K) // conservative size of the "common_code" for the x64 platform
71   };
72 
73   enum {
74     ro = 0,  // read-only shared space in the heap
75     rw = 1,  // read-write shared space in the heap
76     md = 2,  // miscellaneous data for initializing tables, etc.
77     mc = 3,  // miscellaneous code - vtable replacement.
78     n_regions = 4
79   };
80 
81   // Accessor functions to save shared space created for metadata, which has
82   // extra space allocated at the end for miscellaneous data and code.
set_max_alignment(int alignment)83   static void set_max_alignment(int alignment) {
84     CDS_ONLY(_max_alignment = alignment);
85   }
86 
max_alignment()87   static int max_alignment() {
88     CDS_ONLY(return _max_alignment);
89     NOT_CDS(return 0);
90   }
91 
92   static void prepare_for_dumping() NOT_CDS_RETURN;
93   static void preload_and_dump(TRAPS) NOT_CDS_RETURN;
94   static int preload_and_dump(const char * class_list_path,
95                               GrowableArray<Klass*>* class_promote_order,
96                               TRAPS) NOT_CDS_RETURN_(0);
97 
shared_rs()98   static ReservedSpace* shared_rs() {
99     CDS_ONLY(return _shared_rs);
100     NOT_CDS(return NULL);
101   }
102 
set_shared_rs(ReservedSpace * rs)103   static void set_shared_rs(ReservedSpace* rs) {
104     CDS_ONLY(_shared_rs = rs;)
105   }
106 
set_archive_loading_failed()107   static void set_archive_loading_failed() {
108     _archive_loading_failed = true;
109   }
110   static bool map_shared_spaces(FileMapInfo* mapinfo) NOT_CDS_RETURN_(false);
111   static void initialize_shared_spaces() NOT_CDS_RETURN;
112 
113   // Return true if given address is in the mapped shared space.
114   static bool is_in_shared_space(const void* p) NOT_CDS_RETURN_(false);
115 
116   static void generate_vtable_methods(void** vtbl_list,
117                                       void** vtable,
118                                       char** md_top, char* md_end,
119                                       char** mc_top, char* mc_end);
120   static void serialize(SerializeClosure* sc);
121 
122   // JVM/TI RedefineClasses() support:
123   // Remap the shared readonly space to shared readwrite, private if
124   // sharing is enabled. Simply returns true if sharing is not enabled
125   // or if the remapping has already been done by a prior call.
126   static bool remap_shared_readonly_as_readwrite() NOT_CDS_RETURN_(true);
remapped_readwrite()127   static bool remapped_readwrite() {
128     CDS_ONLY(return _remapped_readwrite);
129     NOT_CDS(return false);
130   }
131 
132   static void print_shared_spaces();
133 
134   static bool try_link_class(InstanceKlass* ik, TRAPS);
135   static void link_one_shared_class(Klass* obj, TRAPS);
136   static void check_one_shared_class(Klass* obj);
137   static void link_and_cleanup_shared_classes(TRAPS);
138 
139   static int count_class(const char* classlist_file);
140   static void estimate_regions_size() NOT_CDS_RETURN;
141 };
142 #endif // SHARE_VM_MEMORY_METASPACE_SHARED_HPP
143