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24 
25 #ifndef SHARE_VM_MEMORY_METASPACESHARED_HPP
26 #define SHARE_VM_MEMORY_METASPACESHARED_HPP
27 
28 #include "classfile/compactHashtable.hpp"
29 #include "memory/allocation.hpp"
30 #include "memory/memRegion.hpp"
31 #include "memory/virtualspace.hpp"
32 #include "oops/oop.hpp"
33 #include "utilities/exceptions.hpp"
34 #include "utilities/macros.hpp"
35 #include "utilities/resourceHash.hpp"
36 
37 #define MAX_SHARED_DELTA                (0x7FFFFFFF)
38 
39 class FileMapInfo;
40 
41 class MetaspaceSharedStats {
42 public:
MetaspaceSharedStats()43   MetaspaceSharedStats() {
44     memset(this, 0, sizeof(*this));
45   }
46   CompactHashtableStats symbol;
47   CompactHashtableStats string;
48 };
49 
50 // Class Data Sharing Support
51 class MetaspaceShared : AllStatic {
52 
53   // CDS support
54   static ReservedSpace _shared_rs;
55   static VirtualSpace _shared_vs;
56   static int _max_alignment;
57   static MetaspaceSharedStats _stats;
58   static bool _has_error_classes;
59   static bool _archive_loading_failed;
60   static bool _remapped_readwrite;
61   static bool _open_archive_heap_region_mapped;
62   static address _cds_i2i_entry_code_buffers;
63   static size_t  _cds_i2i_entry_code_buffers_size;
64   static size_t  _core_spaces_size;
65  public:
66   enum {
67     // core archive spaces
68     mc = 0,  // miscellaneous code for method trampolines
69     rw = 1,  // read-write shared space in the heap
70     ro = 2,  // read-only shared space in the heap
71     md = 3,  // miscellaneous data for initializing tables, etc.
72     num_core_spaces = 4, // number of non-string regions
73 
74     // optional mapped spaces
75     // Currently it only contains class file data.
76     od = num_core_spaces,
77     num_non_heap_spaces = od + 1,
78 
79     // mapped java heap regions
80     first_string = od + 1, // index of first string region
81     max_strings = 2, // max number of string regions in string space
82     last_string = first_string + max_strings - 1,
83     first_open_archive_heap_region = first_string + max_strings,
84     max_open_archive_heap_region = 2,
85 
86     last_valid_region = first_open_archive_heap_region + max_open_archive_heap_region - 1,
87     n_regions =  last_valid_region + 1 // total number of regions
88   };
89 
90   static void prepare_for_dumping() NOT_CDS_RETURN;
91   static void preload_and_dump(TRAPS) NOT_CDS_RETURN;
92   static int preload_classes(const char * class_list_path,
93                              TRAPS) NOT_CDS_RETURN_(0);
94 
95 #if INCLUDE_CDS_JAVA_HEAP
96  private:
obj_equals(oop const & p1,oop const & p2)97   static bool obj_equals(oop const& p1, oop const& p2) {
98     return p1 == p2;
99   }
100   static unsigned obj_hash(oop const& p);
101 
102   typedef ResourceHashtable<oop, oop,
103       MetaspaceShared::obj_hash,
104       MetaspaceShared::obj_equals,
105       15889, // prime number
106       ResourceObj::C_HEAP> ArchivedObjectCache;
107   static ArchivedObjectCache* _archive_object_cache;
108 
109  public:
archive_object_cache()110   static ArchivedObjectCache* archive_object_cache() {
111     return _archive_object_cache;
112   }
113   static oop find_archived_heap_object(oop obj);
114   static oop archive_heap_object(oop obj, Thread* THREAD);
115   static oop materialize_archived_object(narrowOop v);
116   static void archive_klass_objects(Thread* THREAD);
117 #endif
118 
119   static bool is_archive_object(oop p) NOT_CDS_JAVA_HEAP_RETURN_(false);
120 
is_heap_object_archiving_allowed()121   static bool is_heap_object_archiving_allowed() {
122     CDS_JAVA_HEAP_ONLY(return (UseG1GC && UseCompressedOops && UseCompressedClassPointers);)
123     NOT_CDS_JAVA_HEAP(return false;)
124   }
create_archive_object_cache()125   static void create_archive_object_cache() {
126     CDS_JAVA_HEAP_ONLY(_archive_object_cache = new (ResourceObj::C_HEAP, mtClass)ArchivedObjectCache(););
127   }
destroy_archive_object_cache()128   static void destroy_archive_object_cache() {
129     CDS_JAVA_HEAP_ONLY(delete _archive_object_cache; _archive_object_cache = NULL;);
130   }
131   static void fixup_mapped_heap_regions() NOT_CDS_JAVA_HEAP_RETURN;
132 
133   static void dump_closed_archive_heap_objects(GrowableArray<MemRegion> * closed_archive) NOT_CDS_JAVA_HEAP_RETURN;
134 
135   static void dump_open_archive_heap_objects(GrowableArray<MemRegion> * open_archive) NOT_CDS_JAVA_HEAP_RETURN;
set_open_archive_heap_region_mapped()136   static void set_open_archive_heap_region_mapped() {
137     CDS_JAVA_HEAP_ONLY(_open_archive_heap_region_mapped = true);
138     NOT_CDS_JAVA_HEAP_RETURN;
139   }
open_archive_heap_region_mapped()140   static bool open_archive_heap_region_mapped() {
141     CDS_JAVA_HEAP_ONLY(return _open_archive_heap_region_mapped);
142     NOT_CDS_JAVA_HEAP_RETURN_(false);
143   }
144 
shared_rs()145   static ReservedSpace* shared_rs() {
146     CDS_ONLY(return &_shared_rs);
147     NOT_CDS(return NULL);
148   }
149   static void commit_shared_space_to(char* newtop) NOT_CDS_RETURN;
core_spaces_size()150   static size_t core_spaces_size() {
151     return _core_spaces_size;
152   }
153   static void initialize_dumptime_shared_and_meta_spaces() NOT_CDS_RETURN;
154   static void initialize_runtime_shared_and_meta_spaces() NOT_CDS_RETURN;
155   static void post_initialize(TRAPS) NOT_CDS_RETURN;
156 
157   // Delta of this object from the bottom of the archive.
object_delta(void * obj)158   static uintx object_delta(void* obj) {
159     assert(DumpSharedSpaces, "supported only for dumping");
160     assert(shared_rs()->contains(obj), "must be");
161     address base_address = address(shared_rs()->base());
162     uintx delta = address(obj) - base_address;
163     return delta;
164   }
165 
set_archive_loading_failed()166   static void set_archive_loading_failed() {
167     _archive_loading_failed = true;
168   }
169   static bool map_shared_spaces(FileMapInfo* mapinfo) NOT_CDS_RETURN_(false);
170   static void initialize_shared_spaces() NOT_CDS_RETURN;
171 
172   // Return true if given address is in the shared metaspace regions (i.e., excluding any
173   // mapped shared heap regions.)
is_in_shared_metaspace(const void * p)174   static bool is_in_shared_metaspace(const void* p) {
175     // If no shared metaspace regions are mapped, MetaspceObj::_shared_metaspace_{base,top} will
176     // both be NULL and all values of p will be rejected quickly.
177     return (p < MetaspaceObj::shared_metaspace_top() && p >= MetaspaceObj::shared_metaspace_base());
178   }
179 
180   // Return true if given address is in the shared region corresponding to the idx
181   static bool is_in_shared_region(const void* p, int idx) NOT_CDS_RETURN_(false);
182 
is_heap_region(int idx)183   static bool is_heap_region(int idx) {
184     CDS_JAVA_HEAP_ONLY(return (idx >= MetaspaceShared::first_string &&
185                                idx < MetaspaceShared::first_open_archive_heap_region +
186                                      MetaspaceShared::max_open_archive_heap_region));
187     NOT_CDS_JAVA_HEAP_RETURN_(false);
188   }
is_string_region(int idx)189   static bool is_string_region(int idx) {
190     CDS_JAVA_HEAP_ONLY(return (idx >= MetaspaceShared::first_string &&
191                                idx < MetaspaceShared::first_string + MetaspaceShared::max_strings));
192     NOT_CDS_JAVA_HEAP_RETURN_(false);
193   }
is_open_archive_heap_region(int idx)194   static bool is_open_archive_heap_region(int idx) {
195     CDS_JAVA_HEAP_ONLY(return (idx >= MetaspaceShared::first_open_archive_heap_region &&
196                                idx < MetaspaceShared::first_open_archive_heap_region +
197                                      MetaspaceShared::max_open_archive_heap_region));
198     NOT_CDS_JAVA_HEAP_RETURN_(false);
199   }
200   static bool is_in_trampoline_frame(address addr) NOT_CDS_RETURN_(false);
201 
202   static void allocate_cpp_vtable_clones();
203   static intptr_t* clone_cpp_vtables(intptr_t* p);
204   static void zero_cpp_vtable_clones_for_writing();
205   static void patch_cpp_vtable_pointers();
206   static bool is_valid_shared_method(const Method* m) NOT_CDS_RETURN_(false);
207   static void serialize(SerializeClosure* sc) NOT_CDS_RETURN;
208 
stats()209   static MetaspaceSharedStats* stats() {
210     return &_stats;
211   }
212 
213   static void report_out_of_space(const char* name, size_t needed_bytes);
214 
215   // JVM/TI RedefineClasses() support:
216   // Remap the shared readonly space to shared readwrite, private if
217   // sharing is enabled. Simply returns true if sharing is not enabled
218   // or if the remapping has already been done by a prior call.
219   static bool remap_shared_readonly_as_readwrite() NOT_CDS_RETURN_(true);
remapped_readwrite()220   static bool remapped_readwrite() {
221     CDS_ONLY(return _remapped_readwrite);
222     NOT_CDS(return false);
223   }
224 
225   static bool try_link_class(InstanceKlass* ik, TRAPS);
226   static void link_and_cleanup_shared_classes(TRAPS);
227   static void check_shared_class_loader_type(InstanceKlass* ik);
228 
229   // Allocate a block of memory from the "mc", "ro", or "rw" regions.
230   static char* misc_code_space_alloc(size_t num_bytes);
231   static char* read_only_space_alloc(size_t num_bytes);
232 
233   static char* read_only_space_top();
234 
235   template <typename T>
new_ro_array(int length)236   static Array<T>* new_ro_array(int length) {
237 #if INCLUDE_CDS
238     size_t byte_size = Array<T>::byte_sizeof(length, sizeof(T));
239     Array<T>* array = (Array<T>*)read_only_space_alloc(byte_size);
240     array->initialize(length);
241     return array;
242 #else
243     return NULL;
244 #endif
245   }
246 
247   static address cds_i2i_entry_code_buffers(size_t total_size);
248 
cds_i2i_entry_code_buffers()249   static address cds_i2i_entry_code_buffers() {
250     return _cds_i2i_entry_code_buffers;
251   }
cds_i2i_entry_code_buffers_size()252   static size_t cds_i2i_entry_code_buffers_size() {
253     return _cds_i2i_entry_code_buffers_size;
254   }
255   static void relocate_klass_ptr(oop o);
256 
257   static Klass* get_relocated_klass(Klass *k);
258 
259 private:
260   static void read_extra_data(const char* filename, TRAPS) NOT_CDS_RETURN;
261 };
262 #endif // SHARE_VM_MEMORY_METASPACESHARED_HPP
263