Mon, 07 Feb 2011 10:34:39 -0800
7017124: Fix some VM stats to avoid 32-bit overflow
Summary: Added new method inc_stat_counter() to increment long statistic values and use atomic long load and store.
Reviewed-by: dholmes, jrose, phh, never
1 /*
2 * Copyright (c) 1997, 2011, 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 */
25 #include "precompiled.hpp"
26 #include "memory/allocation.hpp"
27 #include "memory/allocation.inline.hpp"
28 #include "memory/resourceArea.hpp"
29 #include "runtime/os.hpp"
30 #include "runtime/task.hpp"
31 #include "runtime/threadCritical.hpp"
32 #include "utilities/ostream.hpp"
33 #ifdef TARGET_OS_FAMILY_linux
34 # include "os_linux.inline.hpp"
35 #endif
36 #ifdef TARGET_OS_FAMILY_solaris
37 # include "os_solaris.inline.hpp"
38 #endif
39 #ifdef TARGET_OS_FAMILY_windows
40 # include "os_windows.inline.hpp"
41 #endif
43 void* CHeapObj::operator new(size_t size){
44 return (void *) AllocateHeap(size, "CHeapObj-new");
45 }
47 void CHeapObj::operator delete(void* p){
48 FreeHeap(p);
49 }
51 void* StackObj::operator new(size_t size) { ShouldNotCallThis(); return 0; };
52 void StackObj::operator delete(void* p) { ShouldNotCallThis(); };
53 void* _ValueObj::operator new(size_t size) { ShouldNotCallThis(); return 0; };
54 void _ValueObj::operator delete(void* p) { ShouldNotCallThis(); };
56 void* ResourceObj::operator new(size_t size, allocation_type type) {
57 address res;
58 switch (type) {
59 case C_HEAP:
60 res = (address)AllocateHeap(size, "C_Heap: ResourceOBJ");
61 DEBUG_ONLY(set_allocation_type(res, C_HEAP);)
62 break;
63 case RESOURCE_AREA:
64 // new(size) sets allocation type RESOURCE_AREA.
65 res = (address)operator new(size);
66 break;
67 default:
68 ShouldNotReachHere();
69 }
70 return res;
71 }
73 void ResourceObj::operator delete(void* p) {
74 assert(((ResourceObj *)p)->allocated_on_C_heap(),
75 "delete only allowed for C_HEAP objects");
76 DEBUG_ONLY(((ResourceObj *)p)->_allocation_t[0] = (uintptr_t)badHeapOopVal;)
77 FreeHeap(p);
78 }
80 #ifdef ASSERT
81 void ResourceObj::set_allocation_type(address res, allocation_type type) {
82 // Set allocation type in the resource object
83 uintptr_t allocation = (uintptr_t)res;
84 assert((allocation & allocation_mask) == 0, "address should be aligned to 4 bytes at least");
85 assert(type <= allocation_mask, "incorrect allocation type");
86 ResourceObj* resobj = (ResourceObj *)res;
87 resobj->_allocation_t[0] = ~(allocation + type);
88 if (type != STACK_OR_EMBEDDED) {
89 // Called from operator new() and CollectionSetChooser(),
90 // set verification value.
91 resobj->_allocation_t[1] = (uintptr_t)&(resobj->_allocation_t[1]) + type;
92 }
93 }
95 ResourceObj::allocation_type ResourceObj::get_allocation_type() const {
96 assert(~(_allocation_t[0] | allocation_mask) == (uintptr_t)this, "lost resource object");
97 return (allocation_type)((~_allocation_t[0]) & allocation_mask);
98 }
100 bool ResourceObj::is_type_set() const {
101 allocation_type type = (allocation_type)(_allocation_t[1] & allocation_mask);
102 return get_allocation_type() == type &&
103 (_allocation_t[1] - type) == (uintptr_t)(&_allocation_t[1]);
104 }
106 ResourceObj::ResourceObj() { // default constructor
107 if (~(_allocation_t[0] | allocation_mask) != (uintptr_t)this) {
108 // Operator new() is not called for allocations
109 // on stack and for embedded objects.
110 set_allocation_type((address)this, STACK_OR_EMBEDDED);
111 } else if (allocated_on_stack()) { // STACK_OR_EMBEDDED
112 // For some reason we got a value which resembles
113 // an embedded or stack object (operator new() does not
114 // set such type). Keep it since it is valid value
115 // (even if it was garbage).
116 // Ignore garbage in other fields.
117 } else if (is_type_set()) {
118 // Operator new() was called and type was set.
119 assert(!allocated_on_stack(),
120 err_msg("not embedded or stack, this(" PTR_FORMAT ") type %d a[0]=(" PTR_FORMAT ") a[1]=(" PTR_FORMAT ")",
121 this, get_allocation_type(), _allocation_t[0], _allocation_t[1]));
122 } else {
123 // Operator new() was not called.
124 // Assume that it is embedded or stack object.
125 set_allocation_type((address)this, STACK_OR_EMBEDDED);
126 }
127 _allocation_t[1] = 0; // Zap verification value
128 }
130 ResourceObj::ResourceObj(const ResourceObj& r) { // default copy constructor
131 // Used in ClassFileParser::parse_constant_pool_entries() for ClassFileStream.
132 // Note: garbage may resembles valid value.
133 assert(~(_allocation_t[0] | allocation_mask) != (uintptr_t)this || !is_type_set(),
134 err_msg("embedded or stack only, this(" PTR_FORMAT ") type %d a[0]=(" PTR_FORMAT ") a[1]=(" PTR_FORMAT ")",
135 this, get_allocation_type(), _allocation_t[0], _allocation_t[1]));
136 set_allocation_type((address)this, STACK_OR_EMBEDDED);
137 _allocation_t[1] = 0; // Zap verification value
138 }
140 ResourceObj& ResourceObj::operator=(const ResourceObj& r) { // default copy assignment
141 // Used in InlineTree::ok_to_inline() for WarmCallInfo.
142 assert(allocated_on_stack(),
143 err_msg("copy only into local, this(" PTR_FORMAT ") type %d a[0]=(" PTR_FORMAT ") a[1]=(" PTR_FORMAT ")",
144 this, get_allocation_type(), _allocation_t[0], _allocation_t[1]));
145 // Keep current _allocation_t value;
146 return *this;
147 }
149 ResourceObj::~ResourceObj() {
150 // allocated_on_C_heap() also checks that encoded (in _allocation) address == this.
151 if (!allocated_on_C_heap()) { // ResourceObj::delete() will zap _allocation for C_heap.
152 _allocation_t[0] = (uintptr_t)badHeapOopVal; // zap type
153 }
154 }
155 #endif // ASSERT
158 void trace_heap_malloc(size_t size, const char* name, void* p) {
159 // A lock is not needed here - tty uses a lock internally
160 tty->print_cr("Heap malloc " INTPTR_FORMAT " " SIZE_FORMAT " %s", p, size, name == NULL ? "" : name);
161 }
164 void trace_heap_free(void* p) {
165 // A lock is not needed here - tty uses a lock internally
166 tty->print_cr("Heap free " INTPTR_FORMAT, p);
167 }
169 bool warn_new_operator = false; // see vm_main
171 //--------------------------------------------------------------------------------------
172 // ChunkPool implementation
174 // MT-safe pool of chunks to reduce malloc/free thrashing
175 // NB: not using Mutex because pools are used before Threads are initialized
176 class ChunkPool {
177 Chunk* _first; // first cached Chunk; its first word points to next chunk
178 size_t _num_chunks; // number of unused chunks in pool
179 size_t _num_used; // number of chunks currently checked out
180 const size_t _size; // size of each chunk (must be uniform)
182 // Our three static pools
183 static ChunkPool* _large_pool;
184 static ChunkPool* _medium_pool;
185 static ChunkPool* _small_pool;
187 // return first element or null
188 void* get_first() {
189 Chunk* c = _first;
190 if (_first) {
191 _first = _first->next();
192 _num_chunks--;
193 }
194 return c;
195 }
197 public:
198 // All chunks in a ChunkPool has the same size
199 ChunkPool(size_t size) : _size(size) { _first = NULL; _num_chunks = _num_used = 0; }
201 // Allocate a new chunk from the pool (might expand the pool)
202 void* allocate(size_t bytes) {
203 assert(bytes == _size, "bad size");
204 void* p = NULL;
205 { ThreadCritical tc;
206 _num_used++;
207 p = get_first();
208 if (p == NULL) p = os::malloc(bytes);
209 }
210 if (p == NULL)
211 vm_exit_out_of_memory(bytes, "ChunkPool::allocate");
213 return p;
214 }
216 // Return a chunk to the pool
217 void free(Chunk* chunk) {
218 assert(chunk->length() + Chunk::aligned_overhead_size() == _size, "bad size");
219 ThreadCritical tc;
220 _num_used--;
222 // Add chunk to list
223 chunk->set_next(_first);
224 _first = chunk;
225 _num_chunks++;
226 }
228 // Prune the pool
229 void free_all_but(size_t n) {
230 // if we have more than n chunks, free all of them
231 ThreadCritical tc;
232 if (_num_chunks > n) {
233 // free chunks at end of queue, for better locality
234 Chunk* cur = _first;
235 for (size_t i = 0; i < (n - 1) && cur != NULL; i++) cur = cur->next();
237 if (cur != NULL) {
238 Chunk* next = cur->next();
239 cur->set_next(NULL);
240 cur = next;
242 // Free all remaining chunks
243 while(cur != NULL) {
244 next = cur->next();
245 os::free(cur);
246 _num_chunks--;
247 cur = next;
248 }
249 }
250 }
251 }
253 // Accessors to preallocated pool's
254 static ChunkPool* large_pool() { assert(_large_pool != NULL, "must be initialized"); return _large_pool; }
255 static ChunkPool* medium_pool() { assert(_medium_pool != NULL, "must be initialized"); return _medium_pool; }
256 static ChunkPool* small_pool() { assert(_small_pool != NULL, "must be initialized"); return _small_pool; }
258 static void initialize() {
259 _large_pool = new ChunkPool(Chunk::size + Chunk::aligned_overhead_size());
260 _medium_pool = new ChunkPool(Chunk::medium_size + Chunk::aligned_overhead_size());
261 _small_pool = new ChunkPool(Chunk::init_size + Chunk::aligned_overhead_size());
262 }
264 static void clean() {
265 enum { BlocksToKeep = 5 };
266 _small_pool->free_all_but(BlocksToKeep);
267 _medium_pool->free_all_but(BlocksToKeep);
268 _large_pool->free_all_but(BlocksToKeep);
269 }
270 };
272 ChunkPool* ChunkPool::_large_pool = NULL;
273 ChunkPool* ChunkPool::_medium_pool = NULL;
274 ChunkPool* ChunkPool::_small_pool = NULL;
276 void chunkpool_init() {
277 ChunkPool::initialize();
278 }
280 void
281 Chunk::clean_chunk_pool() {
282 ChunkPool::clean();
283 }
286 //--------------------------------------------------------------------------------------
287 // ChunkPoolCleaner implementation
288 //
290 class ChunkPoolCleaner : public PeriodicTask {
291 enum { CleaningInterval = 5000 }; // cleaning interval in ms
293 public:
294 ChunkPoolCleaner() : PeriodicTask(CleaningInterval) {}
295 void task() {
296 ChunkPool::clean();
297 }
298 };
300 //--------------------------------------------------------------------------------------
301 // Chunk implementation
303 void* Chunk::operator new(size_t requested_size, size_t length) {
304 // requested_size is equal to sizeof(Chunk) but in order for the arena
305 // allocations to come out aligned as expected the size must be aligned
306 // to expected arean alignment.
307 // expect requested_size but if sizeof(Chunk) doesn't match isn't proper size we must align it.
308 assert(ARENA_ALIGN(requested_size) == aligned_overhead_size(), "Bad alignment");
309 size_t bytes = ARENA_ALIGN(requested_size) + length;
310 switch (length) {
311 case Chunk::size: return ChunkPool::large_pool()->allocate(bytes);
312 case Chunk::medium_size: return ChunkPool::medium_pool()->allocate(bytes);
313 case Chunk::init_size: return ChunkPool::small_pool()->allocate(bytes);
314 default: {
315 void *p = os::malloc(bytes);
316 if (p == NULL)
317 vm_exit_out_of_memory(bytes, "Chunk::new");
318 return p;
319 }
320 }
321 }
323 void Chunk::operator delete(void* p) {
324 Chunk* c = (Chunk*)p;
325 switch (c->length()) {
326 case Chunk::size: ChunkPool::large_pool()->free(c); break;
327 case Chunk::medium_size: ChunkPool::medium_pool()->free(c); break;
328 case Chunk::init_size: ChunkPool::small_pool()->free(c); break;
329 default: os::free(c);
330 }
331 }
333 Chunk::Chunk(size_t length) : _len(length) {
334 _next = NULL; // Chain on the linked list
335 }
338 void Chunk::chop() {
339 Chunk *k = this;
340 while( k ) {
341 Chunk *tmp = k->next();
342 // clear out this chunk (to detect allocation bugs)
343 if (ZapResourceArea) memset(k->bottom(), badResourceValue, k->length());
344 delete k; // Free chunk (was malloc'd)
345 k = tmp;
346 }
347 }
349 void Chunk::next_chop() {
350 _next->chop();
351 _next = NULL;
352 }
355 void Chunk::start_chunk_pool_cleaner_task() {
356 #ifdef ASSERT
357 static bool task_created = false;
358 assert(!task_created, "should not start chuck pool cleaner twice");
359 task_created = true;
360 #endif
361 ChunkPoolCleaner* cleaner = new ChunkPoolCleaner();
362 cleaner->enroll();
363 }
365 //------------------------------Arena------------------------------------------
367 Arena::Arena(size_t init_size) {
368 size_t round_size = (sizeof (char *)) - 1;
369 init_size = (init_size+round_size) & ~round_size;
370 _first = _chunk = new (init_size) Chunk(init_size);
371 _hwm = _chunk->bottom(); // Save the cached hwm, max
372 _max = _chunk->top();
373 set_size_in_bytes(init_size);
374 }
376 Arena::Arena() {
377 _first = _chunk = new (Chunk::init_size) Chunk(Chunk::init_size);
378 _hwm = _chunk->bottom(); // Save the cached hwm, max
379 _max = _chunk->top();
380 set_size_in_bytes(Chunk::init_size);
381 }
383 Arena::Arena(Arena *a) : _chunk(a->_chunk), _hwm(a->_hwm), _max(a->_max), _first(a->_first) {
384 set_size_in_bytes(a->size_in_bytes());
385 }
387 Arena *Arena::move_contents(Arena *copy) {
388 copy->destruct_contents();
389 copy->_chunk = _chunk;
390 copy->_hwm = _hwm;
391 copy->_max = _max;
392 copy->_first = _first;
393 copy->set_size_in_bytes(size_in_bytes());
394 // Destroy original arena
395 reset();
396 return copy; // Return Arena with contents
397 }
399 Arena::~Arena() {
400 destruct_contents();
401 }
403 // Destroy this arenas contents and reset to empty
404 void Arena::destruct_contents() {
405 if (UseMallocOnly && _first != NULL) {
406 char* end = _first->next() ? _first->top() : _hwm;
407 free_malloced_objects(_first, _first->bottom(), end, _hwm);
408 }
409 _first->chop();
410 reset();
411 }
414 // Total of all Chunks in arena
415 size_t Arena::used() const {
416 size_t sum = _chunk->length() - (_max-_hwm); // Size leftover in this Chunk
417 register Chunk *k = _first;
418 while( k != _chunk) { // Whilst have Chunks in a row
419 sum += k->length(); // Total size of this Chunk
420 k = k->next(); // Bump along to next Chunk
421 }
422 return sum; // Return total consumed space.
423 }
426 // Grow a new Chunk
427 void* Arena::grow( size_t x ) {
428 // Get minimal required size. Either real big, or even bigger for giant objs
429 size_t len = MAX2(x, (size_t) Chunk::size);
431 Chunk *k = _chunk; // Get filled-up chunk address
432 _chunk = new (len) Chunk(len);
434 if (_chunk == NULL)
435 vm_exit_out_of_memory(len * Chunk::aligned_overhead_size(), "Arena::grow");
437 if (k) k->set_next(_chunk); // Append new chunk to end of linked list
438 else _first = _chunk;
439 _hwm = _chunk->bottom(); // Save the cached hwm, max
440 _max = _chunk->top();
441 set_size_in_bytes(size_in_bytes() + len);
442 void* result = _hwm;
443 _hwm += x;
444 return result;
445 }
449 // Reallocate storage in Arena.
450 void *Arena::Arealloc(void* old_ptr, size_t old_size, size_t new_size) {
451 assert(new_size >= 0, "bad size");
452 if (new_size == 0) return NULL;
453 #ifdef ASSERT
454 if (UseMallocOnly) {
455 // always allocate a new object (otherwise we'll free this one twice)
456 char* copy = (char*)Amalloc(new_size);
457 size_t n = MIN2(old_size, new_size);
458 if (n > 0) memcpy(copy, old_ptr, n);
459 Afree(old_ptr,old_size); // Mostly done to keep stats accurate
460 return copy;
461 }
462 #endif
463 char *c_old = (char*)old_ptr; // Handy name
464 // Stupid fast special case
465 if( new_size <= old_size ) { // Shrink in-place
466 if( c_old+old_size == _hwm) // Attempt to free the excess bytes
467 _hwm = c_old+new_size; // Adjust hwm
468 return c_old;
469 }
471 // make sure that new_size is legal
472 size_t corrected_new_size = ARENA_ALIGN(new_size);
474 // See if we can resize in-place
475 if( (c_old+old_size == _hwm) && // Adjusting recent thing
476 (c_old+corrected_new_size <= _max) ) { // Still fits where it sits
477 _hwm = c_old+corrected_new_size; // Adjust hwm
478 return c_old; // Return old pointer
479 }
481 // Oops, got to relocate guts
482 void *new_ptr = Amalloc(new_size);
483 memcpy( new_ptr, c_old, old_size );
484 Afree(c_old,old_size); // Mostly done to keep stats accurate
485 return new_ptr;
486 }
489 // Determine if pointer belongs to this Arena or not.
490 bool Arena::contains( const void *ptr ) const {
491 #ifdef ASSERT
492 if (UseMallocOnly) {
493 // really slow, but not easy to make fast
494 if (_chunk == NULL) return false;
495 char** bottom = (char**)_chunk->bottom();
496 for (char** p = (char**)_hwm - 1; p >= bottom; p--) {
497 if (*p == ptr) return true;
498 }
499 for (Chunk *c = _first; c != NULL; c = c->next()) {
500 if (c == _chunk) continue; // current chunk has been processed
501 char** bottom = (char**)c->bottom();
502 for (char** p = (char**)c->top() - 1; p >= bottom; p--) {
503 if (*p == ptr) return true;
504 }
505 }
506 return false;
507 }
508 #endif
509 if( (void*)_chunk->bottom() <= ptr && ptr < (void*)_hwm )
510 return true; // Check for in this chunk
511 for (Chunk *c = _first; c; c = c->next()) {
512 if (c == _chunk) continue; // current chunk has been processed
513 if ((void*)c->bottom() <= ptr && ptr < (void*)c->top()) {
514 return true; // Check for every chunk in Arena
515 }
516 }
517 return false; // Not in any Chunk, so not in Arena
518 }
521 #ifdef ASSERT
522 void* Arena::malloc(size_t size) {
523 assert(UseMallocOnly, "shouldn't call");
524 // use malloc, but save pointer in res. area for later freeing
525 char** save = (char**)internal_malloc_4(sizeof(char*));
526 return (*save = (char*)os::malloc(size));
527 }
529 // for debugging with UseMallocOnly
530 void* Arena::internal_malloc_4(size_t x) {
531 assert( (x&(sizeof(char*)-1)) == 0, "misaligned size" );
532 if (_hwm + x > _max) {
533 return grow(x);
534 } else {
535 char *old = _hwm;
536 _hwm += x;
537 return old;
538 }
539 }
540 #endif
543 //--------------------------------------------------------------------------------------
544 // Non-product code
546 #ifndef PRODUCT
547 // The global operator new should never be called since it will usually indicate
548 // a memory leak. Use CHeapObj as the base class of such objects to make it explicit
549 // that they're allocated on the C heap.
550 // Commented out in product version to avoid conflicts with third-party C++ native code.
551 // %% note this is causing a problem on solaris debug build. the global
552 // new is being called from jdk source and causing data corruption.
553 // src/share/native/sun/awt/font/fontmanager/textcache/hsMemory.cpp::hsSoftNew
554 // define CATCH_OPERATOR_NEW_USAGE if you want to use this.
555 #ifdef CATCH_OPERATOR_NEW_USAGE
556 void* operator new(size_t size){
557 static bool warned = false;
558 if (!warned && warn_new_operator)
559 warning("should not call global (default) operator new");
560 warned = true;
561 return (void *) AllocateHeap(size, "global operator new");
562 }
563 #endif
565 void AllocatedObj::print() const { print_on(tty); }
566 void AllocatedObj::print_value() const { print_value_on(tty); }
568 void AllocatedObj::print_on(outputStream* st) const {
569 st->print_cr("AllocatedObj(" INTPTR_FORMAT ")", this);
570 }
572 void AllocatedObj::print_value_on(outputStream* st) const {
573 st->print("AllocatedObj(" INTPTR_FORMAT ")", this);
574 }
576 julong Arena::_bytes_allocated = 0;
578 void Arena::inc_bytes_allocated(size_t x) { inc_stat_counter(&_bytes_allocated, x); }
580 AllocStats::AllocStats() {
581 start_mallocs = os::num_mallocs;
582 start_frees = os::num_frees;
583 start_malloc_bytes = os::alloc_bytes;
584 start_mfree_bytes = os::free_bytes;
585 start_res_bytes = Arena::_bytes_allocated;
586 }
588 julong AllocStats::num_mallocs() { return os::num_mallocs - start_mallocs; }
589 julong AllocStats::alloc_bytes() { return os::alloc_bytes - start_malloc_bytes; }
590 julong AllocStats::num_frees() { return os::num_frees - start_frees; }
591 julong AllocStats::free_bytes() { return os::free_bytes - start_mfree_bytes; }
592 julong AllocStats::resource_bytes() { return Arena::_bytes_allocated - start_res_bytes; }
593 void AllocStats::print() {
594 tty->print_cr(UINT64_FORMAT " mallocs (" UINT64_FORMAT "MB), "
595 UINT64_FORMAT" frees (" UINT64_FORMAT "MB), " UINT64_FORMAT "MB resrc",
596 num_mallocs(), alloc_bytes()/M, num_frees(), free_bytes()/M, resource_bytes()/M);
597 }
600 // debugging code
601 inline void Arena::free_all(char** start, char** end) {
602 for (char** p = start; p < end; p++) if (*p) os::free(*p);
603 }
605 void Arena::free_malloced_objects(Chunk* chunk, char* hwm, char* max, char* hwm2) {
606 assert(UseMallocOnly, "should not call");
607 // free all objects malloced since resource mark was created; resource area
608 // contains their addresses
609 if (chunk->next()) {
610 // this chunk is full, and some others too
611 for (Chunk* c = chunk->next(); c != NULL; c = c->next()) {
612 char* top = c->top();
613 if (c->next() == NULL) {
614 top = hwm2; // last junk is only used up to hwm2
615 assert(c->contains(hwm2), "bad hwm2");
616 }
617 free_all((char**)c->bottom(), (char**)top);
618 }
619 assert(chunk->contains(hwm), "bad hwm");
620 assert(chunk->contains(max), "bad max");
621 free_all((char**)hwm, (char**)max);
622 } else {
623 // this chunk was partially used
624 assert(chunk->contains(hwm), "bad hwm");
625 assert(chunk->contains(hwm2), "bad hwm2");
626 free_all((char**)hwm, (char**)hwm2);
627 }
628 }
631 ReallocMark::ReallocMark() {
632 #ifdef ASSERT
633 Thread *thread = ThreadLocalStorage::get_thread_slow();
634 _nesting = thread->resource_area()->nesting();
635 #endif
636 }
638 void ReallocMark::check() {
639 #ifdef ASSERT
640 if (_nesting != Thread::current()->resource_area()->nesting()) {
641 fatal("allocation bug: array could grow within nested ResourceMark");
642 }
643 #endif
644 }
646 #endif // Non-product