1/* 2 * Copyright (c) 2012, 2017, 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 39class FileMapInfo; 40 41class MetaspaceSharedStats VALUE_OBJ_CLASS_SPEC { 42public: 43 MetaspaceSharedStats() { 44 memset(this, 0, sizeof(*this)); 45 } 46 CompactHashtableStats symbol; 47 CompactHashtableStats string; 48}; 49 50// Class Data Sharing Support 51class 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 archive_heap_object(oop obj, Thread* THREAD); 117 static void archive_resolved_constants(Thread* THREAD); 118#endif 119 static bool is_heap_object_archiving_allowed() { 120 CDS_JAVA_HEAP_ONLY(return (UseG1GC && UseCompressedOops && UseCompressedClassPointers);) 121 NOT_CDS_JAVA_HEAP(return false;) 122 } 123 static void create_archive_object_cache() { 124 CDS_JAVA_HEAP_ONLY(_archive_object_cache = new (ResourceObj::C_HEAP, mtClass)ArchivedObjectCache();); 125 } 126 static void destroy_archive_object_cache() { 127 CDS_JAVA_HEAP_ONLY(delete _archive_object_cache; _archive_object_cache = NULL;); 128 } 129 static void fixup_mapped_heap_regions() NOT_CDS_JAVA_HEAP_RETURN; 130 131 static void dump_open_archive_heap_objects(GrowableArray<MemRegion> * open_archive) NOT_CDS_JAVA_HEAP_RETURN; 132 static void set_open_archive_heap_region_mapped() { 133 CDS_JAVA_HEAP_ONLY(_open_archive_heap_region_mapped = true); 134 NOT_CDS_JAVA_HEAP_RETURN; 135 } 136 static bool open_archive_heap_region_mapped() { 137 CDS_JAVA_HEAP_ONLY(return _open_archive_heap_region_mapped); 138 NOT_CDS_JAVA_HEAP_RETURN_(false); 139 } 140 141 static ReservedSpace* shared_rs() { 142 CDS_ONLY(return &_shared_rs); 143 NOT_CDS(return NULL); 144 } 145 static void commit_shared_space_to(char* newtop) NOT_CDS_RETURN; 146 static size_t core_spaces_size() { 147 return _core_spaces_size; 148 } 149 static void initialize_shared_rs() NOT_CDS_RETURN; 150 151 // Delta of this object from the bottom of the archive. 152 static uintx object_delta(void* obj) { 153 assert(DumpSharedSpaces, "supported only for dumping"); 154 assert(shared_rs()->contains(obj), "must be"); 155 address base_address = address(shared_rs()->base()); 156 uintx delta = address(obj) - base_address; 157 return delta; 158 } 159 160 static void set_archive_loading_failed() { 161 _archive_loading_failed = true; 162 } 163 static bool map_shared_spaces(FileMapInfo* mapinfo) NOT_CDS_RETURN_(false); 164 static void initialize_shared_spaces() NOT_CDS_RETURN; 165 166 // Return true if given address is in the mapped shared space. 167 static bool is_in_shared_space(const void* p) NOT_CDS_RETURN_(false); 168 169 // Return true if given address is in the shared region corresponding to the idx 170 static bool is_in_shared_region(const void* p, int idx) NOT_CDS_RETURN_(false); 171 172 static bool is_heap_region(int idx) { 173 CDS_JAVA_HEAP_ONLY(return (idx >= MetaspaceShared::first_string && 174 idx < MetaspaceShared::first_open_archive_heap_region + 175 MetaspaceShared::max_open_archive_heap_region)); 176 NOT_CDS_JAVA_HEAP_RETURN_(false); 177 } 178 static bool is_string_region(int idx) { 179 CDS_JAVA_HEAP_ONLY(return (idx >= MetaspaceShared::first_string && 180 idx < MetaspaceShared::first_string + MetaspaceShared::max_strings)); 181 NOT_CDS_JAVA_HEAP_RETURN_(false); 182 } 183 static bool is_open_archive_heap_region(int idx) { 184 CDS_JAVA_HEAP_ONLY(return (idx >= MetaspaceShared::first_open_archive_heap_region && 185 idx < MetaspaceShared::first_open_archive_heap_region + 186 MetaspaceShared::max_open_archive_heap_region)); 187 NOT_CDS_JAVA_HEAP_RETURN_(false); 188 } 189 static bool is_in_trampoline_frame(address addr) NOT_CDS_RETURN_(false); 190 191 static void allocate_cpp_vtable_clones(); 192 static intptr_t* clone_cpp_vtables(intptr_t* p); 193 static void zero_cpp_vtable_clones_for_writing(); 194 static void patch_cpp_vtable_pointers(); 195 static bool is_valid_shared_method(const Method* m) NOT_CDS_RETURN_(false); 196 static void serialize(SerializeClosure* sc); 197 198 static MetaspaceSharedStats* stats() { 199 return &_stats; 200 } 201 202 static void report_out_of_space(const char* name, size_t needed_bytes); 203 204 // JVM/TI RedefineClasses() support: 205 // Remap the shared readonly space to shared readwrite, private if 206 // sharing is enabled. Simply returns true if sharing is not enabled 207 // or if the remapping has already been done by a prior call. 208 static bool remap_shared_readonly_as_readwrite() NOT_CDS_RETURN_(true); 209 static bool remapped_readwrite() { 210 CDS_ONLY(return _remapped_readwrite); 211 NOT_CDS(return false); 212 } 213 214 static void print_shared_spaces(); 215 216 static bool try_link_class(InstanceKlass* ik, TRAPS); 217 static void link_and_cleanup_shared_classes(TRAPS); 218 static void check_shared_class_loader_type(Klass* obj); 219 220 // Allocate a block of memory from the "mc", "ro", or "rw" regions. 221 static char* misc_code_space_alloc(size_t num_bytes); 222 static char* read_only_space_alloc(size_t num_bytes); 223 224 template <typename T> 225 static Array<T>* new_ro_array(int length) { 226#if INCLUDE_CDS 227 size_t byte_size = Array<T>::byte_sizeof(length, sizeof(T)); 228 Array<T>* array = (Array<T>*)read_only_space_alloc(byte_size); 229 array->initialize(length); 230 return array; 231#else 232 return NULL; 233#endif 234 } 235 236 static address cds_i2i_entry_code_buffers(size_t total_size); 237 238 static address cds_i2i_entry_code_buffers() { 239 return _cds_i2i_entry_code_buffers; 240 } 241 static size_t cds_i2i_entry_code_buffers_size() { 242 return _cds_i2i_entry_code_buffers_size; 243 } 244 static void relocate_klass_ptr(oop o); 245}; 246#endif // SHARE_VM_MEMORY_METASPACESHARED_HPP 247