1 /* 2 * Copyright (c) 2012, 2018, 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_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.inline.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: 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 first_open_archive_heap_region = first_string + max_strings, 83 max_open_archive_heap_region = 2, 84 85 last_valid_region = first_open_archive_heap_region + max_open_archive_heap_region - 1, 86 n_regions = last_valid_region + 1 // total number of regions 87 }; 88 89 static void prepare_for_dumping() NOT_CDS_RETURN; 90 static void preload_and_dump(TRAPS) NOT_CDS_RETURN; 91 static int preload_classes(const char * class_list_path, 92 TRAPS) NOT_CDS_RETURN_(0); 93 94 #if INCLUDE_CDS_JAVA_HEAP 95 private: 96 static bool obj_equals(oop const& p1, oop const& p2) { 97 return p1 == p2; 98 } 99 static unsigned obj_hash(oop const& p) { 100 assert(!p->mark()->has_bias_pattern(), 101 "this object should never have been locked"); // so identity_hash won't safepoin 102 unsigned hash = (unsigned)p->identity_hash(); 103 return hash; 104 } 105 typedef ResourceHashtable<oop, oop, 106 MetaspaceShared::obj_hash, 107 MetaspaceShared::obj_equals, 108 15889, // prime number 109 ResourceObj::C_HEAP> ArchivedObjectCache; 110 static ArchivedObjectCache* _archive_object_cache; 111 112 public: 113 static ArchivedObjectCache* archive_object_cache() { 114 return _archive_object_cache; 115 } 116 static oop find_archived_heap_object(oop obj); 117 static oop archive_heap_object(oop obj, Thread* THREAD); 118 static void archive_klass_objects(Thread* THREAD); 119 #endif 120 static bool is_heap_object_archiving_allowed() { 121 CDS_JAVA_HEAP_ONLY(return (UseG1GC && UseCompressedOops && UseCompressedClassPointers);) 122 NOT_CDS_JAVA_HEAP(return false;) 123 } 124 static void create_archive_object_cache() { 125 CDS_JAVA_HEAP_ONLY(_archive_object_cache = new (ResourceObj::C_HEAP, mtClass)ArchivedObjectCache();); 126 } 127 static void destroy_archive_object_cache() { 128 CDS_JAVA_HEAP_ONLY(delete _archive_object_cache; _archive_object_cache = NULL;); 129 } 130 static void fixup_mapped_heap_regions() NOT_CDS_JAVA_HEAP_RETURN; 131 132 static void dump_closed_archive_heap_objects(GrowableArray<MemRegion> * closed_archive) NOT_CDS_JAVA_HEAP_RETURN; 133 134 static void dump_open_archive_heap_objects(GrowableArray<MemRegion> * open_archive) NOT_CDS_JAVA_HEAP_RETURN; 135 static void set_open_archive_heap_region_mapped() { 136 CDS_JAVA_HEAP_ONLY(_open_archive_heap_region_mapped = true); 137 NOT_CDS_JAVA_HEAP_RETURN; 138 } 139 static bool open_archive_heap_region_mapped() { 140 CDS_JAVA_HEAP_ONLY(return _open_archive_heap_region_mapped); 141 NOT_CDS_JAVA_HEAP_RETURN_(false); 142 } 143 144 static ReservedSpace* shared_rs() { 145 CDS_ONLY(return &_shared_rs); 146 NOT_CDS(return NULL); 147 } 148 static void commit_shared_space_to(char* newtop) NOT_CDS_RETURN; 149 static size_t core_spaces_size() { 150 return _core_spaces_size; 151 } 152 static void initialize_dumptime_shared_and_meta_spaces() NOT_CDS_RETURN; 153 static void initialize_runtime_shared_and_meta_spaces() NOT_CDS_RETURN; 154 155 // Delta of this object from the bottom of the archive. 156 static uintx object_delta(void* obj) { 157 assert(DumpSharedSpaces, "supported only for dumping"); 158 assert(shared_rs()->contains(obj), "must be"); 159 address base_address = address(shared_rs()->base()); 160 uintx delta = address(obj) - base_address; 161 return delta; 162 } 163 164 static void set_archive_loading_failed() { 165 _archive_loading_failed = true; 166 } 167 static bool map_shared_spaces(FileMapInfo* mapinfo) NOT_CDS_RETURN_(false); 168 static void initialize_shared_spaces() NOT_CDS_RETURN; 169 170 // Return true if given address is in the shared metaspace regions (i.e., excluding any 171 // mapped shared heap regions.) 172 static bool is_in_shared_metaspace(const void* p) { 173 // If no shared metaspace regions are mapped, MetaspceObj::_shared_metaspace_{base,top} will 174 // both be NULL and all values of p will be rejected quickly. 175 return (p < MetaspaceObj::_shared_metaspace_top && p >= MetaspaceObj::_shared_metaspace_base); 176 } 177 178 // Return true if given address is in the shared region corresponding to the idx 179 static bool is_in_shared_region(const void* p, int idx) NOT_CDS_RETURN_(false); 180 181 static bool is_heap_region(int idx) { 182 CDS_JAVA_HEAP_ONLY(return (idx >= MetaspaceShared::first_string && 183 idx < MetaspaceShared::first_open_archive_heap_region + 184 MetaspaceShared::max_open_archive_heap_region)); 185 NOT_CDS_JAVA_HEAP_RETURN_(false); 186 } 187 static bool is_string_region(int idx) { 188 CDS_JAVA_HEAP_ONLY(return (idx >= MetaspaceShared::first_string && 189 idx < MetaspaceShared::first_string + MetaspaceShared::max_strings)); 190 NOT_CDS_JAVA_HEAP_RETURN_(false); 191 } 192 static bool is_open_archive_heap_region(int idx) { 193 CDS_JAVA_HEAP_ONLY(return (idx >= MetaspaceShared::first_open_archive_heap_region && 194 idx < MetaspaceShared::first_open_archive_heap_region + 195 MetaspaceShared::max_open_archive_heap_region)); 196 NOT_CDS_JAVA_HEAP_RETURN_(false); 197 } 198 static bool is_in_trampoline_frame(address addr) NOT_CDS_RETURN_(false); 199 200 static void allocate_cpp_vtable_clones(); 201 static intptr_t* clone_cpp_vtables(intptr_t* p); 202 static void zero_cpp_vtable_clones_for_writing(); 203 static void patch_cpp_vtable_pointers(); 204 static bool is_valid_shared_method(const Method* m) NOT_CDS_RETURN_(false); 205 static void serialize(SerializeClosure* sc) NOT_CDS_RETURN; 206 static void serialize_well_known_classes(SerializeClosure* soc) NOT_CDS_RETURN; 207 208 static MetaspaceSharedStats* stats() { 209 return &_stats; 210 } 211 212 static void report_out_of_space(const char* name, size_t needed_bytes); 213 214 // JVM/TI RedefineClasses() support: 215 // Remap the shared readonly space to shared readwrite, private if 216 // sharing is enabled. Simply returns true if sharing is not enabled 217 // or if the remapping has already been done by a prior call. 218 static bool remap_shared_readonly_as_readwrite() NOT_CDS_RETURN_(true); 219 static bool remapped_readwrite() { 220 CDS_ONLY(return _remapped_readwrite); 221 NOT_CDS(return false); 222 } 223 224 static void print_shared_spaces(); 225 226 static bool try_link_class(InstanceKlass* ik, TRAPS); 227 static void link_and_cleanup_shared_classes(TRAPS); 228 static void check_shared_class_loader_type(Klass* obj); 229 230 // Allocate a block of memory from the "mc", "ro", or "rw" regions. 231 static char* misc_code_space_alloc(size_t num_bytes); 232 static char* read_only_space_alloc(size_t num_bytes); 233 234 template <typename T> 235 static Array<T>* new_ro_array(int length) { 236 #if INCLUDE_CDS 237 size_t byte_size = Array<T>::byte_sizeof(length, sizeof(T)); 238 Array<T>* array = (Array<T>*)read_only_space_alloc(byte_size); 239 array->initialize(length); 240 return array; 241 #else 242 return NULL; 243 #endif 244 } 245 246 static address cds_i2i_entry_code_buffers(size_t total_size); 247 248 static address cds_i2i_entry_code_buffers() { 249 return _cds_i2i_entry_code_buffers; 250 } 251 static size_t cds_i2i_entry_code_buffers_size() { 252 return _cds_i2i_entry_code_buffers_size; 253 } 254 static void relocate_klass_ptr(oop o); 255 256 static Klass* get_relocated_klass(Klass *k); 257 }; 258 #endif // SHARE_VM_MEMORY_METASPACESHARED_HPP