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3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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24 
25 #ifndef SHARE_VM_MEMORY_ALLOCATION_HPP
26 #define SHARE_VM_MEMORY_ALLOCATION_HPP
27 
28 #include "runtime/globals.hpp"
29 #include "utilities/globalDefinitions.hpp"
30 #include "utilities/macros.hpp"
31 
32 #include <new>
33 
34 class AllocFailStrategy {
35 public:
36   enum AllocFailEnum { EXIT_OOM, RETURN_NULL };
37 };
38 typedef AllocFailStrategy::AllocFailEnum AllocFailType;
39 
40 // The virtual machine must never call one of the implicitly declared
41 // global allocation or deletion functions.  (Such calls may result in
42 // link-time or run-time errors.)  For convenience and documentation of
43 // intended use, classes in the virtual machine may be derived from one
44 // of the following allocation classes, some of which define allocation
45 // and deletion functions.
46 // Note: std::malloc and std::free should never called directly.
47 
48 //
49 // For objects allocated in the resource area (see resourceArea.hpp).
50 // - ResourceObj
51 //
52 // For objects allocated in the C-heap (managed by: free & malloc and tracked with NMT)
53 // - CHeapObj
54 //
55 // For objects allocated on the stack.
56 // - StackObj
57 //
58 // For classes used as name spaces.
59 // - AllStatic
60 //
61 // For classes in Metaspace (class data)
62 // - MetaspaceObj
63 //
64 // The printable subclasses are used for debugging and define virtual
65 // member functions for printing. Classes that avoid allocating the
66 // vtbl entries in the objects should therefore not be the printable
67 // subclasses.
68 //
69 // The following macros and function should be used to allocate memory
70 // directly in the resource area or in the C-heap, The _OBJ variants
71 // of the NEW/FREE_C_HEAP macros are used for alloc/dealloc simple
72 // objects which are not inherited from CHeapObj, note constructor and
73 // destructor are not called. The preferable way to allocate objects
74 // is using the new operator.
75 //
76 // WARNING: The array variant must only be used for a homogenous array
77 // where all objects are of the exact type specified. If subtypes are
78 // stored in the array then must pay attention to calling destructors
79 // at needed.
80 //
81 //   NEW_RESOURCE_ARRAY(type, size)
82 //   NEW_RESOURCE_OBJ(type)
83 //   NEW_C_HEAP_ARRAY(type, size)
84 //   NEW_C_HEAP_OBJ(type, memflags)
85 //   FREE_C_HEAP_ARRAY(type, old)
86 //   FREE_C_HEAP_OBJ(objname, type, memflags)
87 //   char* AllocateHeap(size_t size, const char* name);
88 //   void  FreeHeap(void* p);
89 //
90 
91 // In non product mode we introduce a super class for all allocation classes
92 // that supports printing.
93 // We avoid the superclass in product mode to save space.
94 
95 #ifdef PRODUCT
96 #define ALLOCATION_SUPER_CLASS_SPEC
97 #else
98 #define ALLOCATION_SUPER_CLASS_SPEC : public AllocatedObj
99 class AllocatedObj {
100  public:
101   // Printing support
102   void print() const;
103   void print_value() const;
104 
105   virtual void print_on(outputStream* st) const;
106   virtual void print_value_on(outputStream* st) const;
107 };
108 #endif
109 
110 #define MEMORY_TYPES_DO(f) \
111   /* Memory type by sub systems. It occupies lower byte. */  \
112   f(mtJavaHeap,      "Java Heap")   /* Java heap                                 */ \
113   f(mtClass,         "Class")       /* Java classes                              */ \
114   f(mtThread,        "Thread")      /* thread objects                            */ \
115   f(mtThreadStack,   "Thread Stack")                                                \
116   f(mtCode,          "Code")        /* generated code                            */ \
117   f(mtGC,            "GC")                                                          \
118   f(mtCompiler,      "Compiler")                                                    \
119   f(mtInternal,      "Internal")    /* memory used by VM, but does not belong to */ \
120                                     /* any of above categories, and not used by  */ \
121                                     /* NMT                                       */ \
122   f(mtOther,         "Other")       /* memory not used by VM                     */ \
123   f(mtSymbol,        "Symbol")                                                      \
124   f(mtNMT,           "Native Memory Tracking")  /* memory used by NMT            */ \
125   f(mtClassShared,   "Shared class space")      /* class data sharing            */ \
126   f(mtChunk,         "Arena Chunk") /* chunk that holds content of arenas        */ \
127   f(mtTest,          "Test")        /* Test type for verifying NMT               */ \
128   f(mtTracing,       "Tracing")                                                     \
129   f(mtLogging,       "Logging")                                                     \
130   f(mtArguments,     "Arguments")                                                   \
131   f(mtModule,        "Module")                                                      \
132   f(mtSafepoint,     "Safepoint")                                                   \
133   f(mtNone,          "Unknown")                                                     \
134   //end
135 
136 #define MEMORY_TYPE_DECLARE_ENUM(type, human_readable) \
137   type,
138 
139 /*
140  * Memory types
141  */
142 enum MemoryType {
143   MEMORY_TYPES_DO(MEMORY_TYPE_DECLARE_ENUM)
144   mt_number_of_types   // number of memory types (mtDontTrack
145                        // is not included as validate type)
146 };
147 
148 typedef MemoryType MEMFLAGS;
149 
150 
151 #if INCLUDE_NMT
152 
153 extern bool NMT_track_callsite;
154 
155 #else
156 
157 const bool NMT_track_callsite = false;
158 
159 #endif // INCLUDE_NMT
160 
161 class NativeCallStack;
162 
163 
164 char* AllocateHeap(size_t size,
165                    MEMFLAGS flags,
166                    const NativeCallStack& stack,
167                    AllocFailType alloc_failmode = AllocFailStrategy::EXIT_OOM);
168 char* AllocateHeap(size_t size,
169                    MEMFLAGS flags,
170                    AllocFailType alloc_failmode = AllocFailStrategy::EXIT_OOM);
171 
172 char* ReallocateHeap(char *old,
173                      size_t size,
174                      MEMFLAGS flag,
175                      AllocFailType alloc_failmode = AllocFailStrategy::EXIT_OOM);
176 
177 void FreeHeap(void* p);
178 
179 template <MEMFLAGS F> class CHeapObj ALLOCATION_SUPER_CLASS_SPEC {
180  public:
operator new(size_t size)181   ALWAYSINLINE void* operator new(size_t size) throw() {
182     return (void*)AllocateHeap(size, F);
183   }
184 
operator new(size_t size,const NativeCallStack & stack)185   ALWAYSINLINE void* operator new(size_t size,
186                                   const NativeCallStack& stack) throw() {
187     return (void*)AllocateHeap(size, F, stack);
188   }
189 
operator new(size_t size,const std::nothrow_t &,const NativeCallStack & stack)190   ALWAYSINLINE void* operator new(size_t size, const std::nothrow_t&,
191                                   const NativeCallStack& stack) throw() {
192     return (void*)AllocateHeap(size, F, stack, AllocFailStrategy::RETURN_NULL);
193   }
194 
operator new(size_t size,const std::nothrow_t &)195   ALWAYSINLINE void* operator new(size_t size, const std::nothrow_t&) throw() {
196     return (void*)AllocateHeap(size, F, AllocFailStrategy::RETURN_NULL);
197   }
198 
operator new[](size_t size)199   ALWAYSINLINE void* operator new[](size_t size) throw() {
200     return (void*)AllocateHeap(size, F);
201   }
202 
operator new[](size_t size,const NativeCallStack & stack)203   ALWAYSINLINE void* operator new[](size_t size,
204                                   const NativeCallStack& stack) throw() {
205     return (void*)AllocateHeap(size, F, stack);
206   }
207 
operator new[](size_t size,const std::nothrow_t &,const NativeCallStack & stack)208   ALWAYSINLINE void* operator new[](size_t size, const std::nothrow_t&,
209                                     const NativeCallStack& stack) throw() {
210     return (void*)AllocateHeap(size, F, stack, AllocFailStrategy::RETURN_NULL);
211   }
212 
operator new[](size_t size,const std::nothrow_t &)213   ALWAYSINLINE void* operator new[](size_t size, const std::nothrow_t&) throw() {
214     return (void*)AllocateHeap(size, F, AllocFailStrategy::RETURN_NULL);
215   }
216 
operator delete(void * p)217   void  operator delete(void* p)     { FreeHeap(p); }
operator delete[](void * p)218   void  operator delete [] (void* p) { FreeHeap(p); }
219 };
220 
221 // Base class for objects allocated on the stack only.
222 // Calling new or delete will result in fatal error.
223 
224 class StackObj ALLOCATION_SUPER_CLASS_SPEC {
225  private:
226   void* operator new(size_t size) throw();
227   void* operator new [](size_t size) throw();
228 #ifdef __IBMCPP__
229  public:
230 #endif
231   void  operator delete(void* p);
232   void  operator delete [](void* p);
233 };
234 
235 // Base class for objects stored in Metaspace.
236 // Calling delete will result in fatal error.
237 //
238 // Do not inherit from something with a vptr because this class does
239 // not introduce one.  This class is used to allocate both shared read-only
240 // and shared read-write classes.
241 //
242 
243 class ClassLoaderData;
244 class MetaspaceClosure;
245 
246 class MetaspaceObj {
247   friend class VMStructs;
248   // When CDS is enabled, all shared metaspace objects are mapped
249   // into a single contiguous memory block, so we can use these
250   // two pointers to quickly determine if something is in the
251   // shared metaspace.
252   //
253   // When CDS is not enabled, both pointers are set to NULL.
254   static void* _shared_metaspace_base; // (inclusive) low address
255   static void* _shared_metaspace_top;  // (exclusive) high address
256 
257  public:
258   bool is_metaspace_object() const;
is_shared() const259   bool is_shared() const {
260     // If no shared metaspace regions are mapped, _shared_metaspace_{base,top} will
261     // both be NULL and all values of p will be rejected quickly.
262     return (((void*)this) < _shared_metaspace_top && ((void*)this) >= _shared_metaspace_base);
263   }
264   void print_address_on(outputStream* st) const;  // nonvirtual address printing
265 
set_shared_metaspace_range(void * base,void * top)266   static void set_shared_metaspace_range(void* base, void* top) {
267     _shared_metaspace_base = base;
268     _shared_metaspace_top = top;
269   }
shared_metaspace_base()270   static void* shared_metaspace_base() { return _shared_metaspace_base; }
shared_metaspace_top()271   static void* shared_metaspace_top()  { return _shared_metaspace_top;  }
272 
273 #define METASPACE_OBJ_TYPES_DO(f) \
274   f(Class) \
275   f(Symbol) \
276   f(TypeArrayU1) \
277   f(TypeArrayU2) \
278   f(TypeArrayU4) \
279   f(TypeArrayU8) \
280   f(TypeArrayOther) \
281   f(Method) \
282   f(ConstMethod) \
283   f(MethodData) \
284   f(ConstantPool) \
285   f(ConstantPoolCache) \
286   f(Annotations) \
287   f(MethodCounters)
288 
289 #define METASPACE_OBJ_TYPE_DECLARE(name) name ## Type,
290 #define METASPACE_OBJ_TYPE_NAME_CASE(name) case name ## Type: return #name;
291 
292   enum Type {
293     // Types are MetaspaceObj::ClassType, MetaspaceObj::SymbolType, etc
294     METASPACE_OBJ_TYPES_DO(METASPACE_OBJ_TYPE_DECLARE)
295     _number_of_types
296   };
297 
type_name(Type type)298   static const char * type_name(Type type) {
299     switch(type) {
300     METASPACE_OBJ_TYPES_DO(METASPACE_OBJ_TYPE_NAME_CASE)
301     default:
302       ShouldNotReachHere();
303       return NULL;
304     }
305   }
306 
array_type(size_t elem_size)307   static MetaspaceObj::Type array_type(size_t elem_size) {
308     switch (elem_size) {
309     case 1: return TypeArrayU1Type;
310     case 2: return TypeArrayU2Type;
311     case 4: return TypeArrayU4Type;
312     case 8: return TypeArrayU8Type;
313     default:
314       return TypeArrayOtherType;
315     }
316   }
317 
318   void* operator new(size_t size, ClassLoaderData* loader_data,
319                      size_t word_size,
320                      Type type, Thread* thread) throw();
321                      // can't use TRAPS from this header file.
operator delete(void * p)322   void operator delete(void* p) { ShouldNotCallThis(); }
323 
324   // Declare a *static* method with the same signature in any subclass of MetaspaceObj
325   // that should be read-only by default. See symbol.hpp for an example. This function
326   // is used by the templates in metaspaceClosure.hpp
is_read_only_by_default()327   static bool is_read_only_by_default() { return false; }
328 };
329 
330 // Base class for classes that constitute name spaces.
331 
332 class Arena;
333 
334 class AllStatic {
335  public:
AllStatic()336   AllStatic()  { ShouldNotCallThis(); }
~AllStatic()337   ~AllStatic() { ShouldNotCallThis(); }
338 };
339 
340 
341 extern char* resource_allocate_bytes(size_t size,
342     AllocFailType alloc_failmode = AllocFailStrategy::EXIT_OOM);
343 extern char* resource_allocate_bytes(Thread* thread, size_t size,
344     AllocFailType alloc_failmode = AllocFailStrategy::EXIT_OOM);
345 extern char* resource_reallocate_bytes( char *old, size_t old_size, size_t new_size,
346     AllocFailType alloc_failmode = AllocFailStrategy::EXIT_OOM);
347 extern void resource_free_bytes( char *old, size_t size );
348 
349 //----------------------------------------------------------------------
350 // Base class for objects allocated in the resource area per default.
351 // Optionally, objects may be allocated on the C heap with
352 // new(ResourceObj::C_HEAP) Foo(...) or in an Arena with new (&arena)
353 // ResourceObj's can be allocated within other objects, but don't use
354 // new or delete (allocation_type is unknown).  If new is used to allocate,
355 // use delete to deallocate.
356 class ResourceObj ALLOCATION_SUPER_CLASS_SPEC {
357  public:
358   enum allocation_type { STACK_OR_EMBEDDED = 0, RESOURCE_AREA, C_HEAP, ARENA, allocation_mask = 0x3 };
359   static void set_allocation_type(address res, allocation_type type) NOT_DEBUG_RETURN;
360 #ifdef ASSERT
361  private:
362   // When this object is allocated on stack the new() operator is not
363   // called but garbage on stack may look like a valid allocation_type.
364   // Store negated 'this' pointer when new() is called to distinguish cases.
365   // Use second array's element for verification value to distinguish garbage.
366   uintptr_t _allocation_t[2];
367   bool is_type_set() const;
368  public:
369   allocation_type get_allocation_type() const;
allocated_on_stack() const370   bool allocated_on_stack()    const { return get_allocation_type() == STACK_OR_EMBEDDED; }
allocated_on_res_area() const371   bool allocated_on_res_area() const { return get_allocation_type() == RESOURCE_AREA; }
allocated_on_C_heap() const372   bool allocated_on_C_heap()   const { return get_allocation_type() == C_HEAP; }
allocated_on_arena() const373   bool allocated_on_arena()    const { return get_allocation_type() == ARENA; }
374   ResourceObj(); // default constructor
375   ResourceObj(const ResourceObj& r); // default copy constructor
376   ResourceObj& operator=(const ResourceObj& r); // default copy assignment
377   ~ResourceObj();
378 #endif // ASSERT
379 
380  public:
381   void* operator new(size_t size, allocation_type type, MEMFLAGS flags) throw();
382   void* operator new [](size_t size, allocation_type type, MEMFLAGS flags) throw();
383   void* operator new(size_t size, const std::nothrow_t&  nothrow_constant,
384       allocation_type type, MEMFLAGS flags) throw();
385   void* operator new [](size_t size, const std::nothrow_t&  nothrow_constant,
386       allocation_type type, MEMFLAGS flags) throw();
387 
388   void* operator new(size_t size, Arena *arena) throw();
389 
390   void* operator new [](size_t size, Arena *arena) throw();
391 
operator new(size_t size)392   void* operator new(size_t size) throw() {
393       address res = (address)resource_allocate_bytes(size);
394       DEBUG_ONLY(set_allocation_type(res, RESOURCE_AREA);)
395       return res;
396   }
397 
operator new(size_t size,const std::nothrow_t & nothrow_constant)398   void* operator new(size_t size, const std::nothrow_t& nothrow_constant) throw() {
399       address res = (address)resource_allocate_bytes(size, AllocFailStrategy::RETURN_NULL);
400       DEBUG_ONLY(if (res != NULL) set_allocation_type(res, RESOURCE_AREA);)
401       return res;
402   }
403 
operator new[](size_t size)404   void* operator new [](size_t size) throw() {
405       address res = (address)resource_allocate_bytes(size);
406       DEBUG_ONLY(set_allocation_type(res, RESOURCE_AREA);)
407       return res;
408   }
409 
operator new[](size_t size,const std::nothrow_t & nothrow_constant)410   void* operator new [](size_t size, const std::nothrow_t& nothrow_constant) throw() {
411       address res = (address)resource_allocate_bytes(size, AllocFailStrategy::RETURN_NULL);
412       DEBUG_ONLY(if (res != NULL) set_allocation_type(res, RESOURCE_AREA);)
413       return res;
414   }
415 
416   void  operator delete(void* p);
417   void  operator delete [](void* p);
418 };
419 
420 // One of the following macros must be used when allocating an array
421 // or object to determine whether it should reside in the C heap on in
422 // the resource area.
423 
424 #define NEW_RESOURCE_ARRAY(type, size)\
425   (type*) resource_allocate_bytes((size) * sizeof(type))
426 
427 #define NEW_RESOURCE_ARRAY_RETURN_NULL(type, size)\
428   (type*) resource_allocate_bytes((size) * sizeof(type), AllocFailStrategy::RETURN_NULL)
429 
430 #define NEW_RESOURCE_ARRAY_IN_THREAD(thread, type, size)\
431   (type*) resource_allocate_bytes(thread, (size) * sizeof(type))
432 
433 #define NEW_RESOURCE_ARRAY_IN_THREAD_RETURN_NULL(thread, type, size)\
434   (type*) resource_allocate_bytes(thread, (size) * sizeof(type), AllocFailStrategy::RETURN_NULL)
435 
436 #define REALLOC_RESOURCE_ARRAY(type, old, old_size, new_size)\
437   (type*) resource_reallocate_bytes((char*)(old), (old_size) * sizeof(type), (new_size) * sizeof(type))
438 
439 #define REALLOC_RESOURCE_ARRAY_RETURN_NULL(type, old, old_size, new_size)\
440   (type*) resource_reallocate_bytes((char*)(old), (old_size) * sizeof(type),\
441                                     (new_size) * sizeof(type), AllocFailStrategy::RETURN_NULL)
442 
443 #define FREE_RESOURCE_ARRAY(type, old, size)\
444   resource_free_bytes((char*)(old), (size) * sizeof(type))
445 
446 #define FREE_FAST(old)\
447     /* nop */
448 
449 #define NEW_RESOURCE_OBJ(type)\
450   NEW_RESOURCE_ARRAY(type, 1)
451 
452 #define NEW_RESOURCE_OBJ_RETURN_NULL(type)\
453   NEW_RESOURCE_ARRAY_RETURN_NULL(type, 1)
454 
455 #define NEW_C_HEAP_ARRAY3(type, size, memflags, pc, allocfail)\
456   (type*) AllocateHeap((size) * sizeof(type), memflags, pc, allocfail)
457 
458 #define NEW_C_HEAP_ARRAY2(type, size, memflags, pc)\
459   (type*) (AllocateHeap((size) * sizeof(type), memflags, pc))
460 
461 #define NEW_C_HEAP_ARRAY(type, size, memflags)\
462   (type*) (AllocateHeap((size) * sizeof(type), memflags))
463 
464 #define NEW_C_HEAP_ARRAY2_RETURN_NULL(type, size, memflags, pc)\
465   NEW_C_HEAP_ARRAY3(type, (size), memflags, pc, AllocFailStrategy::RETURN_NULL)
466 
467 #define NEW_C_HEAP_ARRAY_RETURN_NULL(type, size, memflags)\
468   NEW_C_HEAP_ARRAY3(type, (size), memflags, CURRENT_PC, AllocFailStrategy::RETURN_NULL)
469 
470 #define REALLOC_C_HEAP_ARRAY(type, old, size, memflags)\
471   (type*) (ReallocateHeap((char*)(old), (size) * sizeof(type), memflags))
472 
473 #define REALLOC_C_HEAP_ARRAY_RETURN_NULL(type, old, size, memflags)\
474   (type*) (ReallocateHeap((char*)(old), (size) * sizeof(type), memflags, AllocFailStrategy::RETURN_NULL))
475 
476 #define FREE_C_HEAP_ARRAY(type, old) \
477   FreeHeap((char*)(old))
478 
479 // allocate type in heap without calling ctor
480 #define NEW_C_HEAP_OBJ(type, memflags)\
481   NEW_C_HEAP_ARRAY(type, 1, memflags)
482 
483 #define NEW_C_HEAP_OBJ_RETURN_NULL(type, memflags)\
484   NEW_C_HEAP_ARRAY_RETURN_NULL(type, 1, memflags)
485 
486 // deallocate obj of type in heap without calling dtor
487 #define FREE_C_HEAP_OBJ(objname)\
488   FreeHeap((char*)objname);
489 
490 // for statistics
491 #ifndef PRODUCT
492 class AllocStats : StackObj {
493   julong start_mallocs, start_frees;
494   julong start_malloc_bytes, start_mfree_bytes, start_res_bytes;
495  public:
496   AllocStats();
497 
498   julong num_mallocs();    // since creation of receiver
499   julong alloc_bytes();
500   julong num_frees();
501   julong free_bytes();
502   julong resource_bytes();
503   void   print();
504 };
505 #endif
506 
507 
508 //------------------------------ReallocMark---------------------------------
509 // Code which uses REALLOC_RESOURCE_ARRAY should check an associated
510 // ReallocMark, which is declared in the same scope as the reallocated
511 // pointer.  Any operation that could __potentially__ cause a reallocation
512 // should check the ReallocMark.
513 class ReallocMark: public StackObj {
514 protected:
515   NOT_PRODUCT(int _nesting;)
516 
517 public:
518   ReallocMark()   PRODUCT_RETURN;
519   void check()    PRODUCT_RETURN;
520 };
521 
522 // Helper class to allocate arrays that may become large.
523 // Uses the OS malloc for allocations smaller than ArrayAllocatorMallocLimit
524 // and uses mapped memory for larger allocations.
525 // Most OS mallocs do something similar but Solaris malloc does not revert
526 // to mapped memory for large allocations. By default ArrayAllocatorMallocLimit
527 // is set so that we always use malloc except for Solaris where we set the
528 // limit to get mapped memory.
529 template <class E>
530 class ArrayAllocator : public AllStatic {
531  private:
532   static bool should_use_malloc(size_t length);
533 
534   static E* allocate_malloc(size_t length, MEMFLAGS flags);
535   static E* allocate_mmap(size_t length, MEMFLAGS flags);
536 
537   static void free_malloc(E* addr, size_t length);
538   static void free_mmap(E* addr, size_t length);
539 
540  public:
541   static E* allocate(size_t length, MEMFLAGS flags);
542   static E* reallocate(E* old_addr, size_t old_length, size_t new_length, MEMFLAGS flags);
543   static void free(E* addr, size_t length);
544 };
545 
546 // Uses mmaped memory for all allocations. All allocations are initially
547 // zero-filled. No pre-touching.
548 template <class E>
549 class MmapArrayAllocator : public AllStatic {
550  private:
551   static size_t size_for(size_t length);
552 
553  public:
554   static E* allocate_or_null(size_t length, MEMFLAGS flags);
555   static E* allocate(size_t length, MEMFLAGS flags);
556   static void free(E* addr, size_t length);
557 };
558 
559 // Uses malloc:ed memory for all allocations.
560 template <class E>
561 class MallocArrayAllocator : public AllStatic {
562  public:
563   static size_t size_for(size_t length);
564 
565   static E* allocate(size_t length, MEMFLAGS flags);
566   static void free(E* addr);
567 };
568 
569 #endif // SHARE_VM_MEMORY_ALLOCATION_HPP
570