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.
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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