1 /*
2 * Copyright (c) 1997, 2005, 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 #define ARENA_ALIGN_M1 (((size_t)(ARENA_AMALLOC_ALIGNMENT)) - 1)
26 #define ARENA_ALIGN_MASK (~((size_t)ARENA_ALIGN_M1))
27 #define ARENA_ALIGN(x) ((((size_t)(x)) + ARENA_ALIGN_M1) & ARENA_ALIGN_MASK)
28
29 // All classes in the virtual machine must be subclassed
30 // by one of the following allocation classes:
31 //
32 // For objects allocated in the resource area (see resourceArea.hpp).
33 // - ResourceObj
34 //
35 // For objects allocated in the C-heap (managed by: free & malloc).
36 // - CHeapObj
37 //
38 // For objects allocated on the stack.
39 // - StackObj
40 //
41 // For embedded objects.
42 // - ValueObj
43 //
44 // For classes used as name spaces.
45 // - AllStatic
46 //
47 // The printable subclasses are used for debugging and define virtual
48 // member functions for printing. Classes that avoid allocating the
49 // vtbl entries in the objects should therefore not be the printable
50 // subclasses.
51 //
52 // The following macros and function should be used to allocate memory
53 // directly in the resource area or in the C-heap:
54 //
55 // NEW_RESOURCE_ARRAY(type,size)
56 // NEW_RESOURCE_OBJ(type)
57 // NEW_C_HEAP_ARRAY(type,size)
58 // NEW_C_HEAP_OBJ(type)
59 // char* AllocateHeap(size_t size, const char* name);
60 // void FreeHeap(void* p);
61 //
62 // C-heap allocation can be traced using +PrintHeapAllocation.
63 // malloc and free should therefore never called directly.
64
65 // Base class for objects allocated in the C-heap.
66
67 // In non product mode we introduce a super class for all allocation classes
68 // that supports printing.
69 // We avoid the superclass in product mode since some C++ compilers add
70 // a word overhead for empty super classes.
71
72 #ifdef PRODUCT
73 #define ALLOCATION_SUPER_CLASS_SPEC
74 #else
75 #define ALLOCATION_SUPER_CLASS_SPEC : public AllocatedObj
76 class AllocatedObj {
77 public:
78 // Printing support
79 void print() const;
80 void print_value() const;
81
82 virtual void print_on(outputStream* st) const;
83 virtual void print_value_on(outputStream* st) const;
84 };
85 #endif
86
87 class CHeapObj ALLOCATION_SUPER_CLASS_SPEC {
88 public:
89 void* operator new(size_t size);
90 void operator delete(void* p);
91 void* new_array(size_t size);
92 };
93
94 // Base class for objects allocated on the stack only.
95 // Calling new or delete will result in fatal error.
96
97 class StackObj ALLOCATION_SUPER_CLASS_SPEC {
98 public:
99 void* operator new(size_t size);
100 void operator delete(void* p);
101 };
102
103 // Base class for objects used as value objects.
104 // Calling new or delete will result in fatal error.
105 //
106 // Portability note: Certain compilers (e.g. gcc) will
107 // always make classes bigger if it has a superclass, even
108 // if the superclass does not have any virtual methods or
109 // instance fields. The HotSpot implementation relies on this
110 // not to happen. So never make a ValueObj class a direct subclass
111 // of this object, but use the VALUE_OBJ_CLASS_SPEC class instead, e.g.,
112 // like this:
113 //
114 // class A VALUE_OBJ_CLASS_SPEC {
115 // ...
116 // }
117 //
118 // With gcc and possible other compilers the VALUE_OBJ_CLASS_SPEC can
119 // be defined as a an empty string "".
120 //
121 class _ValueObj {
122 public:
123 void* operator new(size_t size);
124 void operator delete(void* p);
125 };
126
127 // Base class for classes that constitute name spaces.
128
129 class AllStatic {
130 public:
131 AllStatic() { ShouldNotCallThis(); }
132 ~AllStatic() { ShouldNotCallThis(); }
133 };
134
135
136 //------------------------------Chunk------------------------------------------
137 // Linked list of raw memory chunks
138 class Chunk: public CHeapObj {
139 protected:
140 Chunk* _next; // Next Chunk in list
141 const size_t _len; // Size of this Chunk
142 public:
143 void* operator new(size_t size, size_t length);
144 void operator delete(void* p);
145 Chunk(size_t length);
146
147 enum {
148 // default sizes; make them slightly smaller than 2**k to guard against
149 // buddy-system style malloc implementations
150 #ifdef _LP64
151 slack = 40, // [RGV] Not sure if this is right, but make it
152 // a multiple of 8.
153 #else
154 slack = 20, // suspected sizeof(Chunk) + internal malloc headers
155 #endif
156
157 init_size = 1*K - slack, // Size of first chunk
158 medium_size= 10*K - slack, // Size of medium-sized chunk
159 size = 32*K - slack, // Default size of an Arena chunk (following the first)
160 non_pool_size = init_size + 32 // An initial size which is not one of above
161 };
162
163 void chop(); // Chop this chunk
164 void next_chop(); // Chop next chunk
165 static size_t aligned_overhead_size(void) { return ARENA_ALIGN(sizeof(Chunk)); }
166
167 size_t length() const { return _len; }
168 Chunk* next() const { return _next; }
169 void set_next(Chunk* n) { _next = n; }
170 // Boundaries of data area (possibly unused)
171 char* bottom() const { return ((char*) this) + aligned_overhead_size(); }
172 char* top() const { return bottom() + _len; }
173 bool contains(char* p) const { return bottom() <= p && p <= top(); }
174
175 // Start the chunk_pool cleaner task
176 static void start_chunk_pool_cleaner_task();
177
178 static void clean_chunk_pool();
179 };
180
181 //------------------------------Arena------------------------------------------
182 // Fast allocation of memory
183 class Arena: public CHeapObj {
184 protected:
185 friend class ResourceMark;
186 friend class HandleMark;
187 friend class NoHandleMark;
188 Chunk *_first; // First chunk
189 Chunk *_chunk; // current chunk
190 char *_hwm, *_max; // High water mark and max in current chunk
191 void* grow(size_t x); // Get a new Chunk of at least size x
192 NOT_PRODUCT(size_t _size_in_bytes;) // Size of arena (used for memory usage tracing)
193 NOT_PRODUCT(static size_t _bytes_allocated;) // total #bytes allocated since start
194 friend class AllocStats;
195 debug_only(void* malloc(size_t size);)
196 debug_only(void* internal_malloc_4(size_t x);)
197 public:
198 Arena();
199 Arena(size_t init_size);
200 Arena(Arena *old);
201 ~Arena();
202 void destruct_contents();
203 char* hwm() const { return _hwm; }
204
205 // Fast allocate in the arena. Common case is: pointer test + increment.
206 void* Amalloc(size_t x) {
207 assert(is_power_of_2(ARENA_AMALLOC_ALIGNMENT) , "should be a power of 2");
208 x = ARENA_ALIGN(x);
209 debug_only(if (UseMallocOnly) return malloc(x);)
210 NOT_PRODUCT(_bytes_allocated += x);
211 if (_hwm + x > _max) {
212 return grow(x);
213 } else {
214 char *old = _hwm;
215 _hwm += x;
216 return old;
217 }
218 }
219 // Further assume size is padded out to words
220 void *Amalloc_4(size_t x) {
221 assert( (x&(sizeof(char*)-1)) == 0, "misaligned size" );
222 debug_only(if (UseMallocOnly) return malloc(x);)
223 NOT_PRODUCT(_bytes_allocated += x);
224 if (_hwm + x > _max) {
225 return grow(x);
226 } else {
227 char *old = _hwm;
228 _hwm += x;
229 return old;
230 }
231 }
232
233 // Allocate with 'double' alignment. It is 8 bytes on sparc.
234 // In other cases Amalloc_D() should be the same as Amalloc_4().
235 void* Amalloc_D(size_t x) {
236 assert( (x&(sizeof(char*)-1)) == 0, "misaligned size" );
237 debug_only(if (UseMallocOnly) return malloc(x);)
238 #if defined(SPARC) && !defined(_LP64)
239 #define DALIGN_M1 7
240 size_t delta = (((size_t)_hwm + DALIGN_M1) & ~DALIGN_M1) - (size_t)_hwm;
241 x += delta;
242 #endif
243 NOT_PRODUCT(_bytes_allocated += x);
244 if (_hwm + x > _max) {
245 return grow(x); // grow() returns a result aligned >= 8 bytes.
246 } else {
247 char *old = _hwm;
248 _hwm += x;
249 #if defined(SPARC) && !defined(_LP64)
250 old += delta; // align to 8-bytes
251 #endif
252 return old;
253 }
254 }
255
256 // Fast delete in area. Common case is: NOP (except for storage reclaimed)
257 void Afree(void *ptr, size_t size) {
258 #ifdef ASSERT
259 if (ZapResourceArea) memset(ptr, badResourceValue, size); // zap freed memory
260 if (UseMallocOnly) return;
261 #endif
262 if (((char*)ptr) + size == _hwm) _hwm = (char*)ptr;
263 }
264
265 void *Arealloc( void *old_ptr, size_t old_size, size_t new_size );
266
267 // Move contents of this arena into an empty arena
268 Arena *move_contents(Arena *empty_arena);
269
270 // Determine if pointer belongs to this Arena or not.
271 bool contains( const void *ptr ) const;
272
273 // Total of all chunks in use (not thread-safe)
274 size_t used() const;
275
276 // Total # of bytes used
277 size_t size_in_bytes() const NOT_PRODUCT({ return _size_in_bytes; }) PRODUCT_RETURN0;
278 void set_size_in_bytes(size_t size) NOT_PRODUCT({ _size_in_bytes = size; }) PRODUCT_RETURN;
279 static void free_malloced_objects(Chunk* chunk, char* hwm, char* max, char* hwm2) PRODUCT_RETURN;
280 static void free_all(char** start, char** end) PRODUCT_RETURN;
281
282 private:
283 // Reset this Arena to empty, access will trigger grow if necessary
284 void reset(void) {
285 _first = _chunk = NULL;
286 _hwm = _max = NULL;
287 }
288 };
289
290 // One of the following macros must be used when allocating
291 // an array or object from an arena
292 #define NEW_ARENA_ARRAY(arena, type, size) \
293 (type*) (arena)->Amalloc((size) * sizeof(type))
294
295 #define REALLOC_ARENA_ARRAY(arena, type, old, old_size, new_size) \
296 (type*) (arena)->Arealloc((char*)(old), (old_size) * sizeof(type), \
297 (new_size) * sizeof(type) )
298
299 #define FREE_ARENA_ARRAY(arena, type, old, size) \
300 (arena)->Afree((char*)(old), (size) * sizeof(type))
301
302 #define NEW_ARENA_OBJ(arena, type) \
303 NEW_ARENA_ARRAY(arena, type, 1)
304
305
306 //%note allocation_1
307 extern char* resource_allocate_bytes(size_t size);
308 extern char* resource_allocate_bytes(Thread* thread, size_t size);
309 extern char* resource_reallocate_bytes( char *old, size_t old_size, size_t new_size);
310 extern void resource_free_bytes( char *old, size_t size );
311
312 //----------------------------------------------------------------------
313 // Base class for objects allocated in the resource area per default.
314 // Optionally, objects may be allocated on the C heap with
315 // new(ResourceObj::C_HEAP) Foo(...) or in an Arena with new (&arena)
316 // ResourceObj's can be allocated within other objects, but don't use
317 // new or delete (allocation_type is unknown). If new is used to allocate,
318 // use delete to deallocate.
319 class ResourceObj ALLOCATION_SUPER_CLASS_SPEC {
320 public:
321 enum allocation_type { STACK_OR_EMBEDDED = 0, RESOURCE_AREA, C_HEAP, ARENA, allocation_mask = 0x3 };
322 static void set_allocation_type(address res, allocation_type type) NOT_DEBUG_RETURN;
323 #ifdef ASSERT
324 private:
325 // When this object is allocated on stack the new() operator is not
326 // called but garbage on stack may look like a valid allocation_type.
327 // Store negated 'this' pointer when new() is called to distinguish cases.
328 uintptr_t _allocation;
329 public:
330 allocation_type get_allocation_type() const;
331 bool allocated_on_stack() const { return get_allocation_type() == STACK_OR_EMBEDDED; }
332 bool allocated_on_res_area() const { return get_allocation_type() == RESOURCE_AREA; }
333 bool allocated_on_C_heap() const { return get_allocation_type() == C_HEAP; }
334 bool allocated_on_arena() const { return get_allocation_type() == ARENA; }
335 ResourceObj(); // default construtor
336 ResourceObj(const ResourceObj& r); // default copy construtor
337 ResourceObj& operator=(const ResourceObj& r); // default copy assignment
338 ~ResourceObj();
339 #endif // ASSERT
340
341 public:
342 void* operator new(size_t size, allocation_type type);
343 void* operator new(size_t size, Arena *arena) {
344 address res = (address)arena->Amalloc(size);
345 DEBUG_ONLY(set_allocation_type(res, ARENA);)
346 return res;
347 }
348 void* operator new(size_t size) {
349 address res = (address)resource_allocate_bytes(size);
350 DEBUG_ONLY(set_allocation_type(res, RESOURCE_AREA);)
351 return res;
352 }
353 void operator delete(void* p);
354 };
355
356 // One of the following macros must be used when allocating an array
357 // or object to determine whether it should reside in the C heap on in
358 // the resource area.
359
360 #define NEW_RESOURCE_ARRAY(type, size)\
361 (type*) resource_allocate_bytes((size) * sizeof(type))
362
363 #define NEW_RESOURCE_ARRAY_IN_THREAD(thread, type, size)\
364 (type*) resource_allocate_bytes(thread, (size) * sizeof(type))
365
366 #define REALLOC_RESOURCE_ARRAY(type, old, old_size, new_size)\
367 (type*) resource_reallocate_bytes((char*)(old), (old_size) * sizeof(type), (new_size) * sizeof(type) )
368
369 #define FREE_RESOURCE_ARRAY(type, old, size)\
370 resource_free_bytes((char*)(old), (size) * sizeof(type))
371
372 #define FREE_FAST(old)\
373 /* nop */
374
375 #define NEW_RESOURCE_OBJ(type)\
376 NEW_RESOURCE_ARRAY(type, 1)
377
378 #define NEW_C_HEAP_ARRAY(type, size)\
379 (type*) (AllocateHeap((size) * sizeof(type), XSTR(type) " in " __FILE__))
380
381 #define REALLOC_C_HEAP_ARRAY(type, old, size)\
382 (type*) (ReallocateHeap((char*)old, (size) * sizeof(type), XSTR(type) " in " __FILE__))
383
384 #define FREE_C_HEAP_ARRAY(type,old) \
385 FreeHeap((char*)(old))
386
387 #define NEW_C_HEAP_OBJ(type)\
388 NEW_C_HEAP_ARRAY(type, 1)
389
390 extern bool warn_new_operator;
391
392 // for statistics
393 #ifndef PRODUCT
394 class AllocStats : StackObj {
395 int start_mallocs, start_frees;
396 size_t start_malloc_bytes, start_res_bytes;
397 public:
398 AllocStats();
399
400 int num_mallocs(); // since creation of receiver
401 size_t alloc_bytes();
402 size_t resource_bytes();
403 int num_frees();
404 void print();
405 };
406 #endif
407
408
409 //------------------------------ReallocMark---------------------------------
410 // Code which uses REALLOC_RESOURCE_ARRAY should check an associated
411 // ReallocMark, which is declared in the same scope as the reallocated
412 // pointer. Any operation that could __potentially__ cause a reallocation
413 // should check the ReallocMark.
414 class ReallocMark: public StackObj {
415 protected:
416 NOT_PRODUCT(int _nesting;)
417
418 public:
419 ReallocMark() PRODUCT_RETURN;
420 void check() PRODUCT_RETURN;
421 };