1 /*
2 * Copyright (c) 1997, 2025, 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_MEMORY_ALLOCATION_HPP
26 #define SHARE_MEMORY_ALLOCATION_HPP
27
28 #include "memory/allStatic.hpp"
29 #include "nmt/memTag.hpp"
30 #include "utilities/debug.hpp"
31 #include "utilities/globalDefinitions.hpp"
32 #include "utilities/macros.hpp"
33
34 #include <new>
35
36 class outputStream;
37 class Thread;
38 class JavaThread;
39
40 class AllocFailStrategy {
41 public:
42 enum AllocFailEnum { EXIT_OOM, RETURN_NULL };
43 };
44 typedef AllocFailStrategy::AllocFailEnum AllocFailType;
45
46 // The virtual machine must never call one of the implicitly declared
47 // global allocation or deletion functions. (Such calls may result in
48 // link-time or run-time errors.) For convenience and documentation of
49 // intended use, classes in the virtual machine may be derived from one
50 // of the following allocation classes, some of which define allocation
51 // and deletion functions.
52 // Note: std::malloc and std::free should never called directly.
53
54 //
55 // For objects allocated in the resource area (see resourceArea.hpp).
56 // - ResourceObj
57 //
58 // For objects allocated in the C-heap (managed by: free & malloc and tracked with NMT)
59 // - CHeapObj
60 //
61 // For objects allocated on the stack.
62 // - StackObj
63 //
64 // For classes used as name spaces.
65 // - AllStatic
66 //
67 // For classes in Metaspace (class data)
68 // - MetaspaceObj
69 //
70 // The printable subclasses are used for debugging and define virtual
71 // member functions for printing. Classes that avoid allocating the
72 // vtbl entries in the objects should therefore not be the printable
73 // subclasses.
74 //
75 // The following macros and function should be used to allocate memory
76 // directly in the resource area or in the C-heap, The _OBJ variants
77 // of the NEW/FREE_C_HEAP macros are used for alloc/dealloc simple
78 // objects which are not inherited from CHeapObj, note constructor and
79 // destructor are not called. The preferable way to allocate objects
80 // is using the new operator.
81 //
82 // WARNING: The array variant must only be used for a homogeneous array
83 // where all objects are of the exact type specified. If subtypes are
84 // stored in the array then must pay attention to calling destructors
85 // at needed.
86 //
87 // NEW_RESOURCE_ARRAY*
88 // REALLOC_RESOURCE_ARRAY*
89 // FREE_RESOURCE_ARRAY*
90 // NEW_RESOURCE_OBJ*
91 // NEW_C_HEAP_ARRAY*
92 // REALLOC_C_HEAP_ARRAY*
93 // FREE_C_HEAP_ARRAY*
94 // NEW_C_HEAP_OBJ*
95 // FREE_C_HEAP_OBJ
96 //
97 // char* AllocateHeap(size_t size, MemTag mem_tag, const NativeCallStack& stack, AllocFailType alloc_failmode = AllocFailStrategy::EXIT_OOM);
98 // char* AllocateHeap(size_t size, MemTag mem_tag, AllocFailType alloc_failmode = AllocFailStrategy::EXIT_OOM);
99 // char* ReallocateHeap(char *old, size_t size, MemTag mem_tag, AllocFailType alloc_failmode = AllocFailStrategy::EXIT_OOM);
100 // void FreeHeap(void* p);
101 //
102
103 extern bool NMT_track_callsite;
104
105 class NativeCallStack;
106
107
108 char* AllocateHeap(size_t size,
109 MemTag mem_tag,
110 const NativeCallStack& stack,
111 AllocFailType alloc_failmode = AllocFailStrategy::EXIT_OOM);
112 char* AllocateHeap(size_t size,
113 MemTag mem_tag,
114 AllocFailType alloc_failmode = AllocFailStrategy::EXIT_OOM);
115
116 char* ReallocateHeap(char *old,
117 size_t size,
118 MemTag mem_tag,
119 AllocFailType alloc_failmode = AllocFailStrategy::EXIT_OOM);
120
121 // handles null pointers
122 void FreeHeap(void* p);
123
124 class CHeapObjBase {
125 public:
126 ALWAYSINLINE void* operator new(size_t size, MemTag mem_tag) {
127 return AllocateHeap(size, mem_tag);
128 }
129
130 ALWAYSINLINE void* operator new(size_t size,
131 MemTag mem_tag,
132 const NativeCallStack& stack) {
133 return AllocateHeap(size, mem_tag, stack);
134 }
135
136 ALWAYSINLINE void* operator new(size_t size,
137 MemTag mem_tag,
138 const std::nothrow_t&,
139 const NativeCallStack& stack) throw() {
140 return AllocateHeap(size, mem_tag, stack, AllocFailStrategy::RETURN_NULL);
141 }
142
143 ALWAYSINLINE void* operator new(size_t size,
144 MemTag mem_tag,
145 const std::nothrow_t&) throw() {
146 return AllocateHeap(size, mem_tag, AllocFailStrategy::RETURN_NULL);
147 }
148
149 ALWAYSINLINE void* operator new[](size_t size, MemTag mem_tag) {
150 return AllocateHeap(size, mem_tag);
151 }
152
153 ALWAYSINLINE void* operator new[](size_t size,
154 MemTag mem_tag,
155 const NativeCallStack& stack) {
156 return AllocateHeap(size, mem_tag, stack);
157 }
158
159 ALWAYSINLINE void* operator new[](size_t size,
160 MemTag mem_tag,
161 const std::nothrow_t&,
162 const NativeCallStack& stack) throw() {
163 return AllocateHeap(size, mem_tag, stack, AllocFailStrategy::RETURN_NULL);
164 }
165
166 ALWAYSINLINE void* operator new[](size_t size,
167 MemTag mem_tag,
168 const std::nothrow_t&) throw() {
169 return AllocateHeap(size, mem_tag, AllocFailStrategy::RETURN_NULL);
170 }
171
172 void operator delete(void* p) { FreeHeap(p); }
173 void operator delete [] (void* p) { FreeHeap(p); }
174 };
175
176 // Uses the implicitly static new and delete operators of CHeapObjBase
177 template<MemTag MT>
178 class CHeapObj {
179 public:
180 ALWAYSINLINE void* operator new(size_t size) {
181 return CHeapObjBase::operator new(size, MT);
182 }
183
184 ALWAYSINLINE void* operator new(size_t size,
185 const NativeCallStack& stack) {
186 return CHeapObjBase::operator new(size, MT, stack);
187 }
188
189 ALWAYSINLINE void* operator new(size_t size, const std::nothrow_t& nt,
190 const NativeCallStack& stack) throw() {
191 return CHeapObjBase::operator new(size, MT, nt, stack);
192 }
193
194 ALWAYSINLINE void* operator new(size_t size, const std::nothrow_t& nt) throw() {
195 return CHeapObjBase::operator new(size, MT, nt);
196 }
197
198 ALWAYSINLINE void* operator new[](size_t size) {
199 return CHeapObjBase::operator new[](size, MT);
200 }
201
202 ALWAYSINLINE void* operator new[](size_t size,
203 const NativeCallStack& stack) {
204 return CHeapObjBase::operator new[](size, MT, stack);
205 }
206
207 ALWAYSINLINE void* operator new[](size_t size, const std::nothrow_t& nt,
208 const NativeCallStack& stack) throw() {
209 return CHeapObjBase::operator new[](size, MT, nt, stack);
210 }
211
212 ALWAYSINLINE void* operator new[](size_t size, const std::nothrow_t& nt) throw() {
213 return CHeapObjBase::operator new[](size, MT, nt);
214 }
215
216 void operator delete(void* p) {
217 CHeapObjBase::operator delete(p);
218 }
219
220 void operator delete [] (void* p) {
221 CHeapObjBase::operator delete[](p);
222 }
223 };
224
225 // Base class for objects allocated on the stack only.
226 // Calling new or delete will result in fatal error.
227
228 class StackObj {
229 public:
230 void* operator new(size_t size) = delete;
231 void* operator new [](size_t size) = delete;
232 void operator delete(void* p) = delete;
233 void operator delete [](void* p) = delete;
234 };
235
236 // Base class for objects stored in Metaspace.
237 // Calling delete will result in fatal error.
238 //
239 // Do not inherit from something with a vptr because this class does
240 // not introduce one. This class is used to allocate both shared read-only
241 // and shared read-write classes.
242 //
243
244 class ClassLoaderData;
245 class MetaspaceClosure;
246
247 class MetaspaceObj {
248 // There are functions that all subtypes of MetaspaceObj are expected
249 // to implement, so that templates which are defined for this class hierarchy
250 // can work uniformly. Within the sub-hierarchy of Metadata, these are virtuals.
251 // Elsewhere in the hierarchy of MetaspaceObj, type(), size(), and/or on_stack()
252 // can be static if constant.
253 //
254 // The following functions are required by MetaspaceClosure:
255 // void metaspace_pointers_do(MetaspaceClosure* it) { <walk my refs> }
256 // int size() const { return align_up(sizeof(<This>), wordSize) / wordSize; }
257 // MetaspaceObj::Type type() const { return <This>Type; }
258 //
259 // The following functions are required by MetadataFactory::free_metadata():
260 // bool on_stack() { return false; }
261 // void deallocate_contents(ClassLoaderData* loader_data);
262
263 friend class VMStructs;
264 // When CDS is enabled, all shared metaspace objects are mapped
265 // into a single contiguous memory block, so we can use these
266 // two pointers to quickly determine if something is in the
267 // shared metaspace.
268 // When CDS is not enabled, both pointers are set to null.
269 static void* _shared_metaspace_base; // (inclusive) low address
270 static void* _shared_metaspace_top; // (exclusive) high address
271
272 public:
273
274 // Returns true if the pointer points to a valid MetaspaceObj. A valid
275 // MetaspaceObj is MetaWord-aligned and contained within either
276 // non-shared or shared metaspace.
277 static bool is_valid(const MetaspaceObj* p);
278
279 #if INCLUDE_CDS
280 static bool is_shared(const MetaspaceObj* p) {
281 // If no shared metaspace regions are mapped, _shared_metaspace_{base,top} will
282 // both be null and all values of p will be rejected quickly.
283 return (((void*)p) < _shared_metaspace_top &&
284 ((void*)p) >= _shared_metaspace_base);
285 }
286 bool is_shared() const { return MetaspaceObj::is_shared(this); }
287 #else
288 static bool is_shared(const MetaspaceObj* p) { return false; }
289 bool is_shared() const { return false; }
290 #endif
291
292 void print_address_on(outputStream* st) const; // nonvirtual address printing
293
294 static void set_shared_metaspace_range(void* base, void* top) {
295 _shared_metaspace_base = base;
296 _shared_metaspace_top = top;
297 }
298
299 static void* shared_metaspace_base() { return _shared_metaspace_base; }
300 static void* shared_metaspace_top() { return _shared_metaspace_top; }
301
302 #define METASPACE_OBJ_TYPES_DO(f) \
303 f(Class) \
304 f(Symbol) \
305 f(TypeArrayU1) \
306 f(TypeArrayU2) \
307 f(TypeArrayU4) \
308 f(TypeArrayU8) \
309 f(TypeArrayOther) \
310 f(Method) \
311 f(ConstMethod) \
312 f(MethodData) \
313 f(ConstantPool) \
314 f(ConstantPoolCache) \
315 f(Annotations) \
316 f(MethodCounters) \
317 f(RecordComponent)
318
319 #define METASPACE_OBJ_TYPE_DECLARE(name) name ## Type,
320 #define METASPACE_OBJ_TYPE_NAME_CASE(name) case name ## Type: return #name;
321
322 enum Type {
323 // Types are MetaspaceObj::ClassType, MetaspaceObj::SymbolType, etc
324 METASPACE_OBJ_TYPES_DO(METASPACE_OBJ_TYPE_DECLARE)
325 _number_of_types
326 };
327
328 static const char * type_name(Type type) {
329 switch(type) {
330 METASPACE_OBJ_TYPES_DO(METASPACE_OBJ_TYPE_NAME_CASE)
331 default:
332 ShouldNotReachHere();
333 return nullptr;
334 }
335 }
336
337 static MetaspaceObj::Type array_type(size_t elem_size) {
338 switch (elem_size) {
339 case 1: return TypeArrayU1Type;
340 case 2: return TypeArrayU2Type;
341 case 4: return TypeArrayU4Type;
342 case 8: return TypeArrayU8Type;
343 default:
344 return TypeArrayOtherType;
345 }
346 }
347
348 void* operator new(size_t size, ClassLoaderData* loader_data,
349 size_t word_size,
350 Type type, JavaThread* thread) throw();
351 // can't use TRAPS from this header file.
352 void* operator new(size_t size, ClassLoaderData* loader_data,
353 size_t word_size,
354 Type type) throw();
355 void operator delete(void* p) = delete;
356
357 // Declare a *static* method with the same signature in any subclass of MetaspaceObj
358 // that should be read-only by default. See symbol.hpp for an example. This function
359 // is used by the templates in metaspaceClosure.hpp
360 static bool is_read_only_by_default() { return false; }
361 };
362
363 // Base class for classes that constitute name spaces.
364
365 class Arena;
366
367 extern char* resource_allocate_bytes(size_t size,
368 AllocFailType alloc_failmode = AllocFailStrategy::EXIT_OOM);
369 extern char* resource_allocate_bytes(Thread* thread, size_t size,
370 AllocFailType alloc_failmode = AllocFailStrategy::EXIT_OOM);
371 extern char* resource_reallocate_bytes( char *old, size_t old_size, size_t new_size,
372 AllocFailType alloc_failmode = AllocFailStrategy::EXIT_OOM);
373 extern void resource_free_bytes( Thread* thread, char *old, size_t size );
374
375 //----------------------------------------------------------------------
376 // Base class for objects allocated in the resource area.
377 class ResourceObj {
378 public:
379 void* operator new(size_t size) {
380 return resource_allocate_bytes(size);
381 }
382
383 void* operator new(size_t size, const std::nothrow_t& nothrow_constant) throw() {
384 return resource_allocate_bytes(size, AllocFailStrategy::RETURN_NULL);
385 }
386
387 void* operator new [](size_t size) throw() = delete;
388 void* operator new [](size_t size, const std::nothrow_t& nothrow_constant) throw() = delete;
389
390 void operator delete(void* p) = delete;
391 void operator delete [](void* p) = delete;
392 };
393
394 class ArenaObj {
395 public:
396 void* operator new(size_t size, Arena *arena) throw();
397 void* operator new [](size_t size, Arena *arena) throw() = delete;
398
399 void* operator new [](size_t size) throw() = delete;
400 void* operator new [](size_t size, const std::nothrow_t& nothrow_constant) throw() = delete;
401
402 void operator delete(void* p) = delete;
403 void operator delete [](void* p) = delete;
404 };
405
406 //----------------------------------------------------------------------
407 // Base class for objects allocated in the resource area per default.
408 // Optionally, objects may be allocated on the C heap with
409 // new (AnyObj::C_HEAP) Foo(...) or in an Arena with new (&arena).
410 // AnyObj's can be allocated within other objects, but don't use
411 // new or delete (allocation_type is unknown). If new is used to allocate,
412 // use delete to deallocate.
413 class AnyObj {
414 public:
415 enum allocation_type { STACK_OR_EMBEDDED = 0, RESOURCE_AREA, C_HEAP, ARENA, allocation_mask = 0x3 };
416 static void set_allocation_type(address res, allocation_type type) NOT_DEBUG_RETURN;
417 #ifdef ASSERT
418 private:
419 // When this object is allocated on stack the new() operator is not
420 // called but garbage on stack may look like a valid allocation_type.
421 // Store negated 'this' pointer when new() is called to distinguish cases.
422 // Use second array's element for verification value to distinguish garbage.
423 uintptr_t _allocation_t[2];
424 bool is_type_set() const;
425 void initialize_allocation_info();
426 public:
427 allocation_type get_allocation_type() const;
428 bool allocated_on_stack_or_embedded() const { return get_allocation_type() == STACK_OR_EMBEDDED; }
429 bool allocated_on_res_area() const { return get_allocation_type() == RESOURCE_AREA; }
430 bool allocated_on_C_heap() const { return get_allocation_type() == C_HEAP; }
431 bool allocated_on_arena() const { return get_allocation_type() == ARENA; }
432 protected:
433 AnyObj(); // default constructor
434 AnyObj(const AnyObj& r); // default copy constructor
435 AnyObj& operator=(const AnyObj& r); // default copy assignment
436 ~AnyObj();
437 #endif // ASSERT
438
439 public:
440 // CHeap allocations
441 void* operator new(size_t size, MemTag mem_tag) throw();
442 void* operator new [](size_t size, MemTag mem_tag) throw() = delete;
443 void* operator new(size_t size, const std::nothrow_t& nothrow_constant, MemTag mem_tag) throw();
444 void* operator new [](size_t size, const std::nothrow_t& nothrow_constant, MemTag mem_tag) throw() = delete;
445
446 // Arena allocations
447 void* operator new(size_t size, Arena *arena);
448 void* operator new [](size_t size, Arena *arena) = delete;
449
450 // Resource allocations
451 void* operator new(size_t size) {
452 address res = (address)resource_allocate_bytes(size);
453 DEBUG_ONLY(set_allocation_type(res, RESOURCE_AREA);)
454 return res;
455 }
456 void* operator new(size_t size, const std::nothrow_t& nothrow_constant) throw() {
457 address res = (address)resource_allocate_bytes(size, AllocFailStrategy::RETURN_NULL);
458 DEBUG_ONLY(if (res != nullptr) set_allocation_type(res, RESOURCE_AREA);)
459 return res;
460 }
461
462 void* operator new [](size_t size) = delete;
463 void* operator new [](size_t size, const std::nothrow_t& nothrow_constant) = delete;
464 void operator delete(void* p);
465 void operator delete [](void* p) = delete;
466
467 #ifndef PRODUCT
468 // Printing support
469 void print() const;
470 virtual void print_on(outputStream* st) const;
471 #endif // PRODUCT
472 };
473
474 // One of the following macros must be used when allocating an array
475 // or object to determine whether it should reside in the C heap on in
476 // the resource area.
477
478 #define NEW_RESOURCE_ARRAY(type, size)\
479 (type*) resource_allocate_bytes((size) * sizeof(type))
480
481 #define NEW_RESOURCE_ARRAY_RETURN_NULL(type, size)\
482 (type*) resource_allocate_bytes((size) * sizeof(type), AllocFailStrategy::RETURN_NULL)
483
484 #define NEW_RESOURCE_ARRAY_IN_THREAD(thread, type, size)\
485 (type*) resource_allocate_bytes(thread, (size) * sizeof(type))
486
487 #define NEW_RESOURCE_ARRAY_IN_THREAD_RETURN_NULL(thread, type, size)\
488 (type*) resource_allocate_bytes(thread, (size) * sizeof(type), AllocFailStrategy::RETURN_NULL)
489
490 #define REALLOC_RESOURCE_ARRAY(type, old, old_size, new_size)\
491 (type*) resource_reallocate_bytes((char*)(old), (old_size) * sizeof(type), (new_size) * sizeof(type))
492
493 #define REALLOC_RESOURCE_ARRAY_RETURN_NULL(type, old, old_size, new_size)\
494 (type*) resource_reallocate_bytes((char*)(old), (old_size) * sizeof(type),\
495 (new_size) * sizeof(type), AllocFailStrategy::RETURN_NULL)
496
497 #define FREE_RESOURCE_ARRAY(type, old, size)\
498 resource_free_bytes(Thread::current(), (char*)(old), (size) * sizeof(type))
499
500 #define FREE_RESOURCE_ARRAY_IN_THREAD(thread, type, old, size)\
501 resource_free_bytes(thread, (char*)(old), (size) * sizeof(type))
502
503 #define FREE_FAST(old)\
504 /* nop */
505
506 #define NEW_RESOURCE_OBJ(type)\
507 NEW_RESOURCE_ARRAY(type, 1)
508
509 #define NEW_RESOURCE_OBJ_RETURN_NULL(type)\
510 NEW_RESOURCE_ARRAY_RETURN_NULL(type, 1)
511
512 #define NEW_C_HEAP_ARRAY3(type, size, mem_tag, pc, allocfail)\
513 (type*) AllocateHeap((size) * sizeof(type), mem_tag, pc, allocfail)
514
515 #define NEW_C_HEAP_ARRAY2(type, size, mem_tag, pc)\
516 (type*) (AllocateHeap((size) * sizeof(type), mem_tag, pc))
517
518 #define NEW_C_HEAP_ARRAY(type, size, mem_tag)\
519 (type*) (AllocateHeap((size) * sizeof(type), mem_tag))
520
521 #define NEW_C_HEAP_ARRAY2_RETURN_NULL(type, size, mem_tag, pc)\
522 NEW_C_HEAP_ARRAY3(type, (size), mem_tag, pc, AllocFailStrategy::RETURN_NULL)
523
524 #define NEW_C_HEAP_ARRAY_RETURN_NULL(type, size, mem_tag)\
525 NEW_C_HEAP_ARRAY2(type, (size), mem_tag, AllocFailStrategy::RETURN_NULL)
526
527 #define REALLOC_C_HEAP_ARRAY(type, old, size, mem_tag)\
528 (type*) (ReallocateHeap((char*)(old), (size) * sizeof(type), mem_tag))
529
530 #define REALLOC_C_HEAP_ARRAY_RETURN_NULL(type, old, size, mem_tag)\
531 (type*) (ReallocateHeap((char*)(old), (size) * sizeof(type), mem_tag, AllocFailStrategy::RETURN_NULL))
532
533 #define FREE_C_HEAP_ARRAY(type, old) \
534 FreeHeap((char*)(old))
535
536 // allocate type in heap without calling ctor
537 #define NEW_C_HEAP_OBJ(type, mem_tag)\
538 NEW_C_HEAP_ARRAY(type, 1, mem_tag)
539
540 #define NEW_C_HEAP_OBJ_RETURN_NULL(type, mem_tag)\
541 NEW_C_HEAP_ARRAY_RETURN_NULL(type, 1, mem_tag)
542
543 // deallocate obj of type in heap without calling dtor
544 #define FREE_C_HEAP_OBJ(objname)\
545 FreeHeap((char*)objname);
546
547
548 //------------------------------ReallocMark---------------------------------
549 // Code which uses REALLOC_RESOURCE_ARRAY should check an associated
550 // ReallocMark, which is declared in the same scope as the reallocated
551 // pointer. Any operation that could __potentially__ cause a reallocation
552 // should check the ReallocMark.
553 class ReallocMark: public StackObj {
554 protected:
555 NOT_PRODUCT(int _nesting;)
556
557 public:
558 ReallocMark() PRODUCT_RETURN;
559 void check(Arena* arena = nullptr) PRODUCT_RETURN;
560 };
561
562 // Uses mmapped memory for all allocations. All allocations are initially
563 // zero-filled. No pre-touching.
564 template <class E>
565 class MmapArrayAllocator : public AllStatic {
566 private:
567 static size_t size_for(size_t length);
568
569 public:
570 static E* allocate_or_null(size_t length, MemTag mem_tag);
571 static E* allocate(size_t length, MemTag mem_tag);
572 static void free(E* addr, size_t length);
573 };
574
575 // Uses malloc:ed memory for all allocations.
576 template <class E>
577 class MallocArrayAllocator : public AllStatic {
578 public:
579 static size_t size_for(size_t length);
580
581 static E* allocate(size_t length, MemTag mem_tag);
582 static E* reallocate(E* addr, size_t new_length, MemTag mem_tag);
583 static void free(E* addr);
584 };
585
586 #endif // SHARE_MEMORY_ALLOCATION_HPP