1 #ifdef USE_PRAGMA_IDENT_HDR
2 #pragma ident "@(#)allocation.hpp 1.77 07/05/05 17:05:42 JVM"
3 #endif
4 /*
5 * Copyright 1997-2005 Sun Microsystems, Inc. All Rights Reserved.
6 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
7 *
8 * This code is free software; you can redistribute it and/or modify it
9 * under the terms of the GNU General Public License version 2 only, as
10 * published by the Free Software Foundation.
11 *
12 * This code is distributed in the hope that it will be useful, but WITHOUT
13 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
15 * version 2 for more details (a copy is included in the LICENSE file that
16 * accompanied this code).
17 *
18 * You should have received a copy of the GNU General Public License version
19 * 2 along with this work; if not, write to the Free Software Foundation,
20 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
21 *
22 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
23 * CA 95054 USA or visit www.sun.com if you need additional information or
24 * have any questions.
25 *
26 */
27
28 #define ARENA_ALIGN_M1 (((size_t)(ARENA_AMALLOC_ALIGNMENT)) - 1)
29 #define ARENA_ALIGN_MASK (~((size_t)ARENA_ALIGN_M1))
30 #define ARENA_ALIGN(x) ((((size_t)(x)) + ARENA_ALIGN_M1) & ARENA_ALIGN_MASK)
31
32 // All classes in the virtual machine must be subclassed
33 // by one of the following allocation classes:
34 //
35 // For objects allocated in the resource area (see resourceArea.hpp).
36 // - ResourceObj
37 //
38 // For objects allocated in the C-heap (managed by: free & malloc).
39 // - CHeapObj
40 //
41 // For objects allocated on the stack.
42 // - StackObj
43 //
44 // For embedded objects.
45 // - ValueObj
46 //
47 // For classes used as name spaces.
48 // - AllStatic
49 //
50 // The printable subclasses are used for debugging and define virtual
51 // member functions for printing. Classes that avoid allocating the
52 // vtbl entries in the objects should therefore not be the printable
53 // subclasses.
54 //
55 // The following macros and function should be used to allocate memory
56 // directly in the resource area or in the C-heap:
57 //
58 // NEW_RESOURCE_ARRAY(type,size)
59 // NEW_RESOURCE_OBJ(type)
60 // NEW_C_HEAP_ARRAY(type,size)
61 // NEW_C_HEAP_OBJ(type)
62 // char* AllocateHeap(size_t size, const char* name);
63 // void FreeHeap(void* p);
64 //
65 // C-heap allocation can be traced using +PrintHeapAllocation.
66 // malloc and free should therefore never called directly.
67
68 // Base class for objects allocated in the C-heap.
69
70 // In non product mode we introduce a super class for all allocation classes
71 // that supports printing.
72 // We avoid the superclass in product mode since some C++ compilers add
73 // a word overhead for empty super classes.
74
75 #ifdef PRODUCT
76 #define ALLOCATION_SUPER_CLASS_SPEC
77 #else
78 #define ALLOCATION_SUPER_CLASS_SPEC : public AllocatedObj
79 class AllocatedObj {
80 public:
81 // Printing support
82 void print() const;
83 void print_value() const;
84
85 virtual void print_on(outputStream* st) const;
86 virtual void print_value_on(outputStream* st) const;
87 };
88 #endif
89
90 class CHeapObj ALLOCATION_SUPER_CLASS_SPEC {
91 public:
92 void* operator new(size_t size);
93 void operator delete(void* p);
94 void* new_array(size_t size);
95 };
96
97 // Base class for objects allocated on the stack only.
98 // Calling new or delete will result in fatal error.
99
100 class StackObj ALLOCATION_SUPER_CLASS_SPEC {
101 public:
102 void* operator new(size_t size);
103 void operator delete(void* p);
104 };
105
106 // Base class for objects used as value objects.
107 // Calling new or delete will result in fatal error.
108 //
109 // Portability note: Certain compilers (e.g. gcc) will
110 // always make classes bigger if it has a superclass, even
111 // if the superclass does not have any virtual methods or
112 // instance fields. The HotSpot implementation relies on this
113 // not to happen. So never make a ValueObj class a direct subclass
114 // of this object, but use the VALUE_OBJ_CLASS_SPEC class instead, e.g.,
115 // like this:
116 //
117 // class A VALUE_OBJ_CLASS_SPEC {
118 // ...
119 // }
120 //
121 // With gcc and possible other compilers the VALUE_OBJ_CLASS_SPEC can
122 // be defined as a an empty string "".
123 //
124 class _ValueObj {
125 public:
126 void* operator new(size_t size);
127 void operator delete(void* p);
128 };
129
130 // Base class for classes that constitute name spaces.
131
132 class AllStatic {
133 public:
134 AllStatic() { ShouldNotCallThis(); }
135 ~AllStatic() { ShouldNotCallThis(); }
136 };
137
138
139 //------------------------------Chunk------------------------------------------
140 // Linked list of raw memory chunks
141 class Chunk: public CHeapObj {
142 protected:
143 Chunk* _next; // Next Chunk in list
144 const size_t _len; // Size of this Chunk
145 public:
146 void* operator new(size_t size, size_t length);
147 void operator delete(void* p);
148 Chunk(size_t length);
149
150 enum {
151 // default sizes; make them slightly smaller than 2**k to guard against
152 // buddy-system style malloc implementations
153 #ifdef _LP64
154 slack = 40, // [RGV] Not sure if this is right, but make it
155 // a multiple of 8.
156 #else
157 slack = 20, // suspected sizeof(Chunk) + internal malloc headers
158 #endif
159
160 init_size = 1*K - slack, // Size of first chunk
161 medium_size= 10*K - slack, // Size of medium-sized chunk
162 size = 32*K - slack, // Default size of an Arena chunk (following the first)
163 non_pool_size = init_size + 32 // An initial size which is not one of above
164 };
165
166 void chop(); // Chop this chunk
167 void next_chop(); // Chop next chunk
168 static size_t aligned_overhead_size(void) { return ARENA_ALIGN(sizeof(Chunk)); }
169
170 size_t length() const { return _len; }
171 Chunk* next() const { return _next; }
172 void set_next(Chunk* n) { _next = n; }
173 // Boundaries of data area (possibly unused)
174 char* bottom() const { return ((char*) this) + aligned_overhead_size(); }
175 char* top() const { return bottom() + _len; }
176 bool contains(char* p) const { return bottom() <= p && p <= top(); }
177
178 // Start the chunk_pool cleaner task
179 static void start_chunk_pool_cleaner_task();
180 };
181
182
183 //------------------------------Arena------------------------------------------
184 // Fast allocation of memory
185 class Arena: public CHeapObj {
186 protected:
187 friend class ResourceMark;
188 friend class HandleMark;
189 friend class NoHandleMark;
190 Chunk *_first; // First chunk
191 Chunk *_chunk; // current chunk
192 char *_hwm, *_max; // High water mark and max in current chunk
193 void* grow(size_t x); // Get a new Chunk of at least size x
194 NOT_PRODUCT(size_t _size_in_bytes;) // Size of arena (used for memory usage tracing)
195 NOT_PRODUCT(static size_t _bytes_allocated;) // total #bytes allocated since start
196 friend class AllocStats;
197 debug_only(void* malloc(size_t size);)
198 debug_only(void* internal_malloc_4(size_t x);)
199 public:
200 Arena();
201 Arena(size_t init_size);
202 Arena(Arena *old);
203 ~Arena();
204 void destruct_contents();
205 char* hwm() const { return _hwm; }
206
207 // Fast allocate in the arena. Common case is: pointer test + increment.
208 void* Amalloc(size_t x) {
209 assert(is_power_of_2(ARENA_AMALLOC_ALIGNMENT) , "should be a power of 2");
210 x = ARENA_ALIGN(x);
211 debug_only(if (UseMallocOnly) return malloc(x);)
212 NOT_PRODUCT(_bytes_allocated += x);
213 if (_hwm + x > _max) {
214 return grow(x);
215 } else {
216 char *old = _hwm;
217 _hwm += x;
218 return old;
219 }
220 }
221 // Further assume size is padded out to words
222 void *Amalloc_4(size_t x) {
223 assert( (x&(sizeof(char*)-1)) == 0, "misaligned size" );
224 debug_only(if (UseMallocOnly) return malloc(x);)
225 NOT_PRODUCT(_bytes_allocated += x);
226 if (_hwm + x > _max) {
227 return grow(x);
228 } else {
229 char *old = _hwm;
230 _hwm += x;
231 return old;
232 }
233 }
234
235 // Allocate with 'double' alignment. It is 8 bytes on sparc.
236 // In other cases Amalloc_D() should be the same as Amalloc_4().
237 void* Amalloc_D(size_t x) {
238 assert( (x&(sizeof(char*)-1)) == 0, "misaligned size" );
239 debug_only(if (UseMallocOnly) return malloc(x);)
240 #if defined(SPARC) && !defined(_LP64)
241 #define DALIGN_M1 7
242 size_t delta = (((size_t)_hwm + DALIGN_M1) & ~DALIGN_M1) - (size_t)_hwm;
243 x += delta;
244 #endif
245 NOT_PRODUCT(_bytes_allocated += x);
246 if (_hwm + x > _max) {
247 return grow(x); // grow() returns a result aligned >= 8 bytes.
248 } else {
249 char *old = _hwm;
250 _hwm += x;
251 #if defined(SPARC) && !defined(_LP64)
252 old += delta; // align to 8-bytes
253 #endif
254 return old;
255 }
256 }
257
258 // Fast delete in area. Common case is: NOP (except for storage reclaimed)
259 void Afree(void *ptr, size_t size) {
260 #ifdef ASSERT
261 if (ZapResourceArea) memset(ptr, badResourceValue, size); // zap freed memory
262 if (UseMallocOnly) return;
263 #endif
264 if (((char*)ptr) + size == _hwm) _hwm = (char*)ptr;
265 }
266
267 void *Arealloc( void *old_ptr, size_t old_size, size_t new_size );
268
269 // Move contents of this arena into an empty arena
270 Arena *move_contents(Arena *empty_arena);
271
272 // Determine if pointer belongs to this Arena or not.
273 bool contains( const void *ptr ) const;
274
275 // Total of all chunks in use (not thread-safe)
276 size_t used() const;
277
278 // Total # of bytes used
279 size_t size_in_bytes() const NOT_PRODUCT({ return _size_in_bytes; }) PRODUCT_RETURN0;
280 void set_size_in_bytes(size_t size) NOT_PRODUCT({ _size_in_bytes = size; }) PRODUCT_RETURN;
281 static void free_malloced_objects(Chunk* chunk, char* hwm, char* max, char* hwm2) PRODUCT_RETURN;
282 static void free_all(char** start, char** end) PRODUCT_RETURN;
283
284 private:
285 // Reset this Arena to empty, access will trigger grow if necessary
286 void reset(void) {
287 _first = _chunk = NULL;
288 _hwm = _max = NULL;
289 }
290 };
291
292 // One of the following macros must be used when allocating
293 // an array or object from an arena
294 #define NEW_ARENA_ARRAY(arena, type, size)\
295 (type*) arena->Amalloc((size) * sizeof(type))
296
297 #define REALLOC_ARENA_ARRAY(arena, type, old, old_size, new_size)\
298 (type*) arena->Arealloc((char*)(old), (old_size) * sizeof(type), (new_size) * sizeof(type) )
299
300 #define FREE_ARENA_ARRAY(arena, type, old, size)\
301 arena->Afree((char*)(old), (size) * sizeof(type))
302
303 #define NEW_ARENA_OBJ(arena, type)\
304 NEW_ARENA_ARRAY(arena, type, 1)
305
306
307 //%note allocation_1
308 extern char* resource_allocate_bytes(size_t size);
309 extern char* resource_allocate_bytes(Thread* thread, size_t size);
310 extern char* resource_reallocate_bytes( char *old, size_t old_size, size_t new_size);
311 extern void resource_free_bytes( char *old, size_t size );
312
313 //----------------------------------------------------------------------
314 // Base class for objects allocated in the resource area per default.
315 // Optionally, objects may be allocated on the C heap with
316 // new(ResourceObj::C_HEAP) Foo(...) or in an Arena with new (&arena)
317 // ResourceObj's can be allocated within other objects, but don't use
318 // new or delete (allocation_type is unknown). If new is used to allocate,
319 // use delete to deallocate.
320 class ResourceObj ALLOCATION_SUPER_CLASS_SPEC {
321 public:
322 enum allocation_type { UNKNOWN = 0, C_HEAP, RESOURCE_AREA, ARENA };
323 #ifdef ASSERT
324 private:
325 allocation_type _allocation;
326 public:
327 bool allocated_on_C_heap() { return _allocation == C_HEAP; }
328 #endif // ASSERT
329
330 public:
331 void* operator new(size_t size, allocation_type type);
332 void* operator new(size_t size, Arena *arena) {
333 address res = (address)arena->Amalloc(size);
334 // Set allocation type in the resource object
335 DEBUG_ONLY(((ResourceObj *)res)->_allocation = ARENA;)
336 return res;
337 }
338 void* operator new(size_t size) {
339 address res = (address)resource_allocate_bytes(size);
340 // Set allocation type in the resource object
341 DEBUG_ONLY(((ResourceObj *)res)->_allocation = RESOURCE_AREA;)
342 return res;
343 }
344 void operator delete(void* p);
345 };
346
347 // One of the following macros must be used when allocating an array
348 // or object to determine whether it should reside in the C heap on in
349 // the resource area.
350
351 #define NEW_RESOURCE_ARRAY(type, size)\
352 (type*) resource_allocate_bytes((size) * sizeof(type))
353
354 #define NEW_RESOURCE_ARRAY_IN_THREAD(thread, type, size)\
355 (type*) resource_allocate_bytes(thread, (size) * sizeof(type))
356
357 #define REALLOC_RESOURCE_ARRAY(type, old, old_size, new_size)\
358 (type*) resource_reallocate_bytes((char*)(old), (old_size) * sizeof(type), (new_size) * sizeof(type) )
359
360 #define FREE_RESOURCE_ARRAY(type, old, size)\
361 resource_free_bytes((char*)(old), (size) * sizeof(type))
362
363 #define FREE_FAST(old)\
364 /* nop */
365
366 #define NEW_RESOURCE_OBJ(type)\
367 NEW_RESOURCE_ARRAY(type, 1)
368
369 #define NEW_C_HEAP_ARRAY(type, size)\
370 (type*) (AllocateHeap((size) * sizeof(type), XSTR(type) " in " __FILE__))
371
372 #define REALLOC_C_HEAP_ARRAY(type, old, size)\
373 (type*) (ReallocateHeap((char*)old, (size) * sizeof(type), XSTR(type) " in " __FILE__))
374
375 #define FREE_C_HEAP_ARRAY(type,old) \
376 FreeHeap((char*)(old))
377
378 #define NEW_C_HEAP_OBJ(type)\
379 NEW_C_HEAP_ARRAY(type, 1)
380
381 extern bool warn_new_operator;
382
383 // for statistics
384 #ifndef PRODUCT
385 class AllocStats : StackObj {
386 int start_mallocs, start_frees;
387 size_t start_malloc_bytes, start_res_bytes;
388 public:
389 AllocStats();
390
391 int num_mallocs(); // since creation of receiver
392 size_t alloc_bytes();
393 size_t resource_bytes();
394 int num_frees();
395 void print();
396 };
397 #endif
398
399
400 //------------------------------ReallocMark---------------------------------
401 // Code which uses REALLOC_RESOURCE_ARRAY should check an associated
402 // ReallocMark, which is declared in the same scope as the reallocated
403 // pointer. Any operation that could __potentially__ cause a reallocation
404 // should check the ReallocMark.
405 class ReallocMark: public StackObj {
406 protected:
407 NOT_PRODUCT(int _nesting;)
408
409 public:
410 ReallocMark() PRODUCT_RETURN;
411 void check() PRODUCT_RETURN;
412 };
413