1 /*
2 * Copyright (c) 2019, 2024, 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_CDS_ARCHIVEUTILS_HPP
26 #define SHARE_CDS_ARCHIVEUTILS_HPP
27
28 #include "cds/serializeClosure.hpp"
29 #include "logging/log.hpp"
30 #include "memory/virtualspace.hpp"
31 #include "utilities/bitMap.hpp"
32 #include "utilities/exceptions.hpp"
33 #include "utilities/macros.hpp"
34
35 class BootstrapInfo;
36 class ReservedSpace;
37 class VirtualSpace;
38
39 template<class E> class Array;
40 template<class E> class GrowableArray;
41
42 // ArchivePtrMarker is used to mark the location of pointers embedded in a CDS archive. E.g., when an
43 // InstanceKlass k is dumped, we mark the location of the k->_name pointer by effectively calling
44 // mark_pointer(/*ptr_loc=*/&k->_name). It's required that (_prt_base <= ptr_loc < _ptr_end). _ptr_base is
45 // fixed, but _ptr_end can be expanded as more objects are dumped.
46 class ArchivePtrMarker : AllStatic {
47 static CHeapBitMap* _ptrmap;
48 static CHeapBitMap* _rw_ptrmap;
49 static CHeapBitMap* _ro_ptrmap;
50 static CHeapBitMap* _cc_ptrmap;
51 static VirtualSpace* _vs;
52
53 // Once _ptrmap is compacted, we don't allow bit marking anymore. This is to
54 // avoid unintentional copy operations after the bitmap has been finalized and written.
55 static bool _compacted;
56
57 static address* ptr_base() { return (address*)_vs->low(); } // committed lower bound (inclusive)
58 static address* ptr_end() { return (address*)_vs->high(); } // committed upper bound (exclusive)
59
60 public:
61 static void initialize(CHeapBitMap* ptrmap, VirtualSpace* vs);
62 static void initialize_rw_ro_cc_maps(CHeapBitMap* rw_ptrmap, CHeapBitMap* ro_ptrmap, CHeapBitMap* cc_ptrmap);
63 static void mark_pointer(address* ptr_loc);
64 static void clear_pointer(address* ptr_loc);
65 static void compact(address relocatable_base, address relocatable_end);
66 static void compact(size_t max_non_null_offset);
67
68 template <typename T>
69 static void mark_pointer(T* ptr_loc) {
70 mark_pointer((address*)ptr_loc);
71 }
72
73 template <typename T>
74 static void set_and_mark_pointer(T* ptr_loc, T ptr_value) {
75 *ptr_loc = ptr_value;
76 mark_pointer(ptr_loc);
77 }
78
79 static CHeapBitMap* ptrmap() {
80 return _ptrmap;
81 }
82
83 static CHeapBitMap* rw_ptrmap() {
84 return _rw_ptrmap;
85 }
86
87 static CHeapBitMap* ro_ptrmap() {
88 return _ro_ptrmap;
89 }
90
91 static CHeapBitMap* cc_ptrmap() {
92 return _cc_ptrmap;
93 }
94
95 static void reset_map_and_vs() {
96 _ptrmap = nullptr;
97 _rw_ptrmap = nullptr;
98 _ro_ptrmap = nullptr;
99 _cc_ptrmap = nullptr;
100 _vs = nullptr;
101 }
102 };
103
104 // SharedDataRelocator is used to shift pointers in the CDS archive.
105 //
106 // The CDS archive is basically a contiguous block of memory (divided into several regions)
107 // that contains multiple objects. The objects may contain direct pointers that point to other objects
108 // within the archive (e.g., InstanceKlass::_name points to a Symbol in the archive). During dumping, we
109 // built a bitmap that marks the locations of all these pointers (using ArchivePtrMarker, see comments above).
110 //
111 // The contents of the archive assumes that it’s mapped at the default SharedBaseAddress (e.g. 0x800000000).
112 // If the archive ends up being mapped at a different address (e.g. 0x810000000), SharedDataRelocator
113 // is used to shift each marked pointer by a delta (0x10000000 in this example), so that it points to
114 // the actually mapped location of the target object.
115 class SharedDataRelocator: public BitMapClosure {
116 // for all (address** p), where (is_marked(p) && _patch_base <= p && p < _patch_end) { *p += delta; }
117
118 // Patch all pointers within this region that are marked.
119 address* _patch_base;
120 address* _patch_end;
121
122 // Before patching, all pointers must point to this region.
123 address _valid_old_base;
124 address _valid_old_end;
125
126 // After patching, all pointers must point to this region.
127 address _valid_new_base;
128 address _valid_new_end;
129
130 // How much to relocate for each pointer.
131 intx _delta;
132
133 public:
134 SharedDataRelocator(address* patch_base, address* patch_end,
135 address valid_old_base, address valid_old_end,
136 address valid_new_base, address valid_new_end, intx delta) :
137 _patch_base(patch_base), _patch_end(patch_end),
138 _valid_old_base(valid_old_base), _valid_old_end(valid_old_end),
139 _valid_new_base(valid_new_base), _valid_new_end(valid_new_end),
140 _delta(delta) {
141 log_debug(cds, reloc)("SharedDataRelocator::_patch_base = " PTR_FORMAT, p2i(_patch_base));
142 log_debug(cds, reloc)("SharedDataRelocator::_patch_end = " PTR_FORMAT, p2i(_patch_end));
143 log_debug(cds, reloc)("SharedDataRelocator::_valid_old_base = " PTR_FORMAT, p2i(_valid_old_base));
144 log_debug(cds, reloc)("SharedDataRelocator::_valid_old_end = " PTR_FORMAT, p2i(_valid_old_end));
145 log_debug(cds, reloc)("SharedDataRelocator::_valid_new_base = " PTR_FORMAT, p2i(_valid_new_base));
146 log_debug(cds, reloc)("SharedDataRelocator::_valid_new_end = " PTR_FORMAT, p2i(_valid_new_end));
147 }
148
149 bool do_bit(size_t offset);
150 };
151
152 class DumpRegion {
153 private:
154 const char* _name;
155 char* _base;
156 char* _top;
157 char* _end;
158 uintx _max_delta;
159 bool _is_packed;
160 ReservedSpace* _rs;
161 VirtualSpace* _vs;
162
163 void commit_to(char* newtop);
164
165 public:
166 DumpRegion(const char* name, uintx max_delta = 0)
167 : _name(name), _base(nullptr), _top(nullptr), _end(nullptr),
168 _max_delta(max_delta), _is_packed(false) {}
169
170 char* expand_top_to(char* newtop);
171 char* allocate(size_t num_bytes);
172
173 void append_intptr_t(intptr_t n, bool need_to_mark = false) NOT_CDS_RETURN;
174
175 char* base() const { return _base; }
176 char* top() const { return _top; }
177 char* end() const { return _end; }
178 size_t reserved() const { return _end - _base; }
179 size_t used() const { return _top - _base; }
180 bool is_packed() const { return _is_packed; }
181 bool is_allocatable() const {
182 return !is_packed() && _base != nullptr;
183 }
184
185 void print(size_t total_bytes) const;
186 void print_out_of_space_msg(const char* failing_region, size_t needed_bytes);
187
188 void init(ReservedSpace* rs, VirtualSpace* vs);
189
190 void pack(DumpRegion* next = nullptr);
191
192 bool contains(char* p) {
193 return base() <= p && p < top();
194 }
195 };
196
197 // Closure for serializing initialization data out to a data area to be
198 // written to the shared file.
199
200 class WriteClosure : public SerializeClosure {
201 private:
202 DumpRegion* _dump_region;
203
204 public:
205 WriteClosure(DumpRegion* r) {
206 _dump_region = r;
207 }
208
209 void do_ptr(void** p);
210
211 void do_u4(u4* p) {
212 _dump_region->append_intptr_t((intptr_t)(*p));
213 }
214
215 void do_int(int* p) {
216 _dump_region->append_intptr_t((intptr_t)(*p));
217 }
218
219 void do_bool(bool *p) {
220 _dump_region->append_intptr_t((intptr_t)(*p));
221 }
222
223 void do_tag(int tag) {
224 _dump_region->append_intptr_t((intptr_t)tag);
225 }
226
227 char* region_top() {
228 return _dump_region->top();
229 }
230
231 bool reading() const { return false; }
232 };
233
234 // Closure for serializing initialization data in from a data area
235 // (ptr_array) read from the shared file.
236
237 class ReadClosure : public SerializeClosure {
238 private:
239 intptr_t** _ptr_array;
240
241 inline intptr_t nextPtr() {
242 return *(*_ptr_array)++;
243 }
244
245 public:
246 ReadClosure(intptr_t** ptr_array) { _ptr_array = ptr_array; }
247
248 void do_ptr(void** p);
249 void do_u4(u4* p);
250 void do_int(int* p);
251 void do_bool(bool *p);
252 void do_tag(int tag);
253 bool reading() const { return true; }
254 char* region_top() { return nullptr; }
255 };
256
257 class ArchiveUtils {
258 public:
259 static void log_to_classlist(BootstrapInfo* bootstrap_specifier, TRAPS) NOT_CDS_RETURN;
260
261 template <typename T> static Array<T>* archive_array(GrowableArray<T>* tmp_array);
262
263 // Used in logging: "boot", "boot2", "plat", "app" and "unreg";
264 static const char* class_category(Klass* k);
265
266 static const char* builtin_loader_name_or_null(oop loader); // "boot", "platform", "app", or nullptr
267 static const char* builtin_loader_name(oop loader); // "boot", "platform", or "app". Asserts if not a built-in-loader.
268
269 static bool builtin_loader_from_type(const char* loader_type, oop* value_ret);
270 static oop builtin_loader_from_type(int loader_type);
271 };
272
273 class HeapRootSegments {
274 private:
275 size_t _base_offset;
276 size_t _count;
277 int _roots_count;
278 int _max_size_in_bytes;
279 int _max_size_in_elems;
280
281 public:
282 size_t base_offset() { return _base_offset; }
283 size_t count() { return _count; }
284 int roots_count() { return _roots_count; }
285 int max_size_in_bytes() { return _max_size_in_bytes; }
286 int max_size_in_elems() { return _max_size_in_elems; }
287
288 size_t size_in_bytes(size_t seg_idx);
289 int size_in_elems(size_t seg_idx);
290 size_t segment_offset(size_t seg_idx);
291
292 // Trivial copy assignments are allowed to copy the entire object representation.
293 // We also inline this class into archive header. Therefore, it is important to make
294 // sure any gaps in object representation are initialized to zeroes. This is why
295 // constructors memset before doing field assignments.
296 HeapRootSegments() {
297 memset(this, 0, sizeof(*this));
298 }
299 HeapRootSegments(size_t base_offset, int roots_count, int max_size_in_bytes, int max_size_in_elems) {
300 memset(this, 0, sizeof(*this));
301 _base_offset = base_offset;
302 _count = (roots_count + max_size_in_elems - 1) / max_size_in_elems;
303 _roots_count = roots_count;
304 _max_size_in_bytes = max_size_in_bytes;
305 _max_size_in_elems = max_size_in_elems;
306 }
307
308 // This class is trivially copyable and assignable.
309 HeapRootSegments(const HeapRootSegments&) = default;
310 HeapRootSegments& operator=(const HeapRootSegments&) = default;
311 };
312
313 #endif // SHARE_CDS_ARCHIVEUTILS_HPP