1 /*
   2  * Copyright (c) 1997, 2014, 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 #include "precompiled.hpp"
  26 #include "memory/allocation.hpp"
  27 #include "memory/allocation.inline.hpp"
  28 #include "memory/genCollectedHeap.hpp"
  29 #include "memory/metaspaceShared.hpp"
  30 #include "memory/resourceArea.hpp"
  31 #include "memory/universe.hpp"
  32 #include "runtime/atomic.hpp"
  33 #include "runtime/os.hpp"
  34 #include "runtime/task.hpp"
  35 #include "runtime/threadCritical.hpp"
  36 #include "services/memTracker.hpp"
  37 #include "utilities/ostream.hpp"
  38 
  39 #ifdef TARGET_OS_FAMILY_linux
  40 # include "os_linux.inline.hpp"
  41 #endif
  42 #ifdef TARGET_OS_FAMILY_solaris
  43 # include "os_solaris.inline.hpp"
  44 #endif
  45 #ifdef TARGET_OS_FAMILY_windows
  46 # include "os_windows.inline.hpp"
  47 #endif
  48 #ifdef TARGET_OS_FAMILY_aix
  49 # include "os_aix.inline.hpp"
  50 #endif
  51 #ifdef TARGET_OS_FAMILY_bsd
  52 # include "os_bsd.inline.hpp"
  53 #endif
  54 
  55 void* StackObj::operator new(size_t size)     throw() { ShouldNotCallThis(); return 0; }
  56 void  StackObj::operator delete(void* p)              { ShouldNotCallThis(); }
  57 void* StackObj::operator new [](size_t size)  throw() { ShouldNotCallThis(); return 0; }
  58 void  StackObj::operator delete [](void* p)           { ShouldNotCallThis(); }
  59 
  60 void* _ValueObj::operator new(size_t size)    throw() { ShouldNotCallThis(); return 0; }
  61 void  _ValueObj::operator delete(void* p)             { ShouldNotCallThis(); }
  62 void* _ValueObj::operator new [](size_t size) throw() { ShouldNotCallThis(); return 0; }
  63 void  _ValueObj::operator delete [](void* p)          { ShouldNotCallThis(); }
  64 
  65 void* MetaspaceObj::operator new(size_t size, ClassLoaderData* loader_data,
  66                                  size_t word_size, bool read_only,
  67                                  MetaspaceObj::Type type, TRAPS) throw() {
  68   // Klass has it's own operator new
  69   return Metaspace::allocate(loader_data, word_size, read_only,
  70                              type, CHECK_NULL);
  71 }
  72 
  73 bool MetaspaceObj::is_shared() const {
  74   return MetaspaceShared::is_in_shared_space(this);
  75 }
  76 
  77 bool MetaspaceObj::is_metaspace_object() const {
  78   return Metaspace::contains((void*)this);
  79 }
  80 
  81 void MetaspaceObj::print_address_on(outputStream* st) const {
  82   st->print(" {" INTPTR_FORMAT "}", p2i(this));
  83 }
  84 
  85 void* ResourceObj::operator new(size_t size, allocation_type type, MEMFLAGS flags) throw() {
  86   address res;
  87   switch (type) {
  88    case C_HEAP:
  89     res = (address)AllocateHeap(size, flags, CALLER_PC);
  90     DEBUG_ONLY(set_allocation_type(res, C_HEAP);)
  91     break;
  92    case RESOURCE_AREA:
  93     // new(size) sets allocation type RESOURCE_AREA.
  94     res = (address)operator new(size);
  95     break;
  96    default:
  97     ShouldNotReachHere();
  98   }
  99   return res;
 100 }
 101 
 102 void* ResourceObj::operator new [](size_t size, allocation_type type, MEMFLAGS flags) throw() {
 103   return (address) operator new(size, type, flags);
 104 }
 105 
 106 void* ResourceObj::operator new(size_t size, const std::nothrow_t&  nothrow_constant,
 107     allocation_type type, MEMFLAGS flags) throw() {
 108   //should only call this with std::nothrow, use other operator new() otherwise
 109   address res;
 110   switch (type) {
 111    case C_HEAP:
 112     res = (address)AllocateHeap(size, flags, CALLER_PC, AllocFailStrategy::RETURN_NULL);
 113     DEBUG_ONLY(if (res!= NULL) set_allocation_type(res, C_HEAP);)
 114     break;
 115    case RESOURCE_AREA:
 116     // new(size) sets allocation type RESOURCE_AREA.
 117     res = (address)operator new(size, std::nothrow);
 118     break;
 119    default:
 120     ShouldNotReachHere();
 121   }
 122   return res;
 123 }
 124 
 125 void* ResourceObj::operator new [](size_t size, const std::nothrow_t&  nothrow_constant,
 126     allocation_type type, MEMFLAGS flags) throw() {
 127   return (address)operator new(size, nothrow_constant, type, flags);
 128 }
 129 
 130 void ResourceObj::operator delete(void* p) {
 131   assert(((ResourceObj *)p)->allocated_on_C_heap(),
 132          "delete only allowed for C_HEAP objects");
 133   DEBUG_ONLY(((ResourceObj *)p)->_allocation_t[0] = (uintptr_t)badHeapOopVal;)
 134   FreeHeap(p);
 135 }
 136 
 137 void ResourceObj::operator delete [](void* p) {
 138   operator delete(p);
 139 }
 140 
 141 #ifdef ASSERT
 142 void ResourceObj::set_allocation_type(address res, allocation_type type) {
 143     // Set allocation type in the resource object
 144     uintptr_t allocation = (uintptr_t)res;
 145     assert((allocation & allocation_mask) == 0, err_msg("address should be aligned to 4 bytes at least: " INTPTR_FORMAT, p2i(res)));
 146     assert(type <= allocation_mask, "incorrect allocation type");
 147     ResourceObj* resobj = (ResourceObj *)res;
 148     resobj->_allocation_t[0] = ~(allocation + type);
 149     if (type != STACK_OR_EMBEDDED) {
 150       // Called from operator new() and CollectionSetChooser(),
 151       // set verification value.
 152       resobj->_allocation_t[1] = (uintptr_t)&(resobj->_allocation_t[1]) + type;
 153     }
 154 }
 155 
 156 ResourceObj::allocation_type ResourceObj::get_allocation_type() const {
 157     assert(~(_allocation_t[0] | allocation_mask) == (uintptr_t)this, "lost resource object");
 158     return (allocation_type)((~_allocation_t[0]) & allocation_mask);
 159 }
 160 
 161 bool ResourceObj::is_type_set() const {
 162     allocation_type type = (allocation_type)(_allocation_t[1] & allocation_mask);
 163     return get_allocation_type()  == type &&
 164            (_allocation_t[1] - type) == (uintptr_t)(&_allocation_t[1]);
 165 }
 166 
 167 ResourceObj::ResourceObj() { // default constructor
 168     if (~(_allocation_t[0] | allocation_mask) != (uintptr_t)this) {
 169       // Operator new() is not called for allocations
 170       // on stack and for embedded objects.
 171       set_allocation_type((address)this, STACK_OR_EMBEDDED);
 172     } else if (allocated_on_stack()) { // STACK_OR_EMBEDDED
 173       // For some reason we got a value which resembles
 174       // an embedded or stack object (operator new() does not
 175       // set such type). Keep it since it is valid value
 176       // (even if it was garbage).
 177       // Ignore garbage in other fields.
 178     } else if (is_type_set()) {
 179       // Operator new() was called and type was set.
 180       assert(!allocated_on_stack(),
 181              err_msg("not embedded or stack, this(" PTR_FORMAT ") type %d a[0]=(" PTR_FORMAT ") a[1]=(" PTR_FORMAT ")",
 182                      p2i(this), get_allocation_type(), _allocation_t[0], _allocation_t[1]));
 183     } else {
 184       // Operator new() was not called.
 185       // Assume that it is embedded or stack object.
 186       set_allocation_type((address)this, STACK_OR_EMBEDDED);
 187     }
 188     _allocation_t[1] = 0; // Zap verification value
 189 }
 190 
 191 ResourceObj::ResourceObj(const ResourceObj& r) { // default copy constructor
 192     // Used in ClassFileParser::parse_constant_pool_entries() for ClassFileStream.
 193     // Note: garbage may resembles valid value.
 194     assert(~(_allocation_t[0] | allocation_mask) != (uintptr_t)this || !is_type_set(),
 195            err_msg("embedded or stack only, this(" PTR_FORMAT ") type %d a[0]=(" PTR_FORMAT ") a[1]=(" PTR_FORMAT ")",
 196                    p2i(this), get_allocation_type(), _allocation_t[0], _allocation_t[1]));
 197     set_allocation_type((address)this, STACK_OR_EMBEDDED);
 198     _allocation_t[1] = 0; // Zap verification value
 199 }
 200 
 201 ResourceObj& ResourceObj::operator=(const ResourceObj& r) { // default copy assignment
 202     // Used in InlineTree::ok_to_inline() for WarmCallInfo.
 203     assert(allocated_on_stack(),
 204            err_msg("copy only into local, this(" PTR_FORMAT ") type %d a[0]=(" PTR_FORMAT ") a[1]=(" PTR_FORMAT ")",
 205                    p2i(this), get_allocation_type(), _allocation_t[0], _allocation_t[1]));
 206     // Keep current _allocation_t value;
 207     return *this;
 208 }
 209 
 210 ResourceObj::~ResourceObj() {
 211     // allocated_on_C_heap() also checks that encoded (in _allocation) address == this.
 212     if (!allocated_on_C_heap()) { // ResourceObj::delete() will zap _allocation for C_heap.
 213       _allocation_t[0] = (uintptr_t)badHeapOopVal; // zap type
 214     }
 215 }
 216 #endif // ASSERT
 217 
 218 
 219 void trace_heap_malloc(size_t size, const char* name, void* p) {
 220   // A lock is not needed here - tty uses a lock internally
 221   tty->print_cr("Heap malloc " INTPTR_FORMAT " " SIZE_FORMAT " %s", p2i(p), size, name == NULL ? "" : name);
 222 }
 223 
 224 
 225 void trace_heap_free(void* p) {
 226   // A lock is not needed here - tty uses a lock internally
 227   tty->print_cr("Heap free   " INTPTR_FORMAT, p2i(p));
 228 }
 229 
 230 //--------------------------------------------------------------------------------------
 231 // ChunkPool implementation
 232 
 233 // MT-safe pool of chunks to reduce malloc/free thrashing
 234 // NB: not using Mutex because pools are used before Threads are initialized
 235 class ChunkPool: public CHeapObj<mtInternal> {
 236   Chunk*       _first;        // first cached Chunk; its first word points to next chunk
 237   size_t       _num_chunks;   // number of unused chunks in pool
 238   size_t       _num_used;     // number of chunks currently checked out
 239   const size_t _size;         // size of each chunk (must be uniform)
 240 
 241   // Our four static pools
 242   static ChunkPool* _large_pool;
 243   static ChunkPool* _medium_pool;
 244   static ChunkPool* _small_pool;
 245   static ChunkPool* _tiny_pool;
 246 
 247   // return first element or null
 248   void* get_first() {
 249     Chunk* c = _first;
 250     if (_first) {
 251       _first = _first->next();
 252       _num_chunks--;
 253     }
 254     return c;
 255   }
 256 
 257  public:
 258   // All chunks in a ChunkPool has the same size
 259    ChunkPool(size_t size) : _size(size) { _first = NULL; _num_chunks = _num_used = 0; }
 260 
 261   // Allocate a new chunk from the pool (might expand the pool)
 262   _NOINLINE_ void* allocate(size_t bytes, AllocFailType alloc_failmode) {
 263     assert(bytes == _size, "bad size");
 264     void* p = NULL;
 265     // No VM lock can be taken inside ThreadCritical lock, so os::malloc
 266     // should be done outside ThreadCritical lock due to NMT
 267     { ThreadCritical tc;
 268       _num_used++;
 269       p = get_first();
 270     }
 271     if (p == NULL) p = os::malloc(bytes, mtChunk, CURRENT_PC);
 272     if (p == NULL && alloc_failmode == AllocFailStrategy::EXIT_OOM) {
 273       vm_exit_out_of_memory(bytes, OOM_MALLOC_ERROR, "ChunkPool::allocate");
 274     }
 275     return p;
 276   }
 277 
 278   // Return a chunk to the pool
 279   void free(Chunk* chunk) {
 280     assert(chunk->length() + Chunk::aligned_overhead_size() == _size, "bad size");
 281     ThreadCritical tc;
 282     _num_used--;
 283 
 284     // Add chunk to list
 285     chunk->set_next(_first);
 286     _first = chunk;
 287     _num_chunks++;
 288   }
 289 
 290   // Prune the pool
 291   void free_all_but(size_t n) {
 292     Chunk* cur = NULL;
 293     Chunk* next;
 294     {
 295     // if we have more than n chunks, free all of them
 296     ThreadCritical tc;
 297     if (_num_chunks > n) {
 298       // free chunks at end of queue, for better locality
 299         cur = _first;
 300       for (size_t i = 0; i < (n - 1) && cur != NULL; i++) cur = cur->next();
 301 
 302       if (cur != NULL) {
 303           next = cur->next();
 304         cur->set_next(NULL);
 305         cur = next;
 306 
 307           _num_chunks = n;
 308         }
 309       }
 310     }
 311 
 312     // Free all remaining chunks, outside of ThreadCritical
 313     // to avoid deadlock with NMT
 314         while(cur != NULL) {
 315           next = cur->next();
 316       os::free(cur, mtChunk);
 317           cur = next;
 318         }
 319       }
 320 
 321   // Accessors to preallocated pool's
 322   static ChunkPool* large_pool()  { assert(_large_pool  != NULL, "must be initialized"); return _large_pool;  }
 323   static ChunkPool* medium_pool() { assert(_medium_pool != NULL, "must be initialized"); return _medium_pool; }
 324   static ChunkPool* small_pool()  { assert(_small_pool  != NULL, "must be initialized"); return _small_pool;  }
 325   static ChunkPool* tiny_pool()   { assert(_tiny_pool   != NULL, "must be initialized"); return _tiny_pool;   }
 326 
 327   static void initialize() {
 328     _large_pool  = new ChunkPool(Chunk::size        + Chunk::aligned_overhead_size());
 329     _medium_pool = new ChunkPool(Chunk::medium_size + Chunk::aligned_overhead_size());
 330     _small_pool  = new ChunkPool(Chunk::init_size   + Chunk::aligned_overhead_size());
 331     _tiny_pool   = new ChunkPool(Chunk::tiny_size   + Chunk::aligned_overhead_size());
 332   }
 333 
 334   static void clean() {
 335     enum { BlocksToKeep = 5 };
 336      _tiny_pool->free_all_but(BlocksToKeep);
 337      _small_pool->free_all_but(BlocksToKeep);
 338      _medium_pool->free_all_but(BlocksToKeep);
 339      _large_pool->free_all_but(BlocksToKeep);
 340   }
 341 };
 342 
 343 ChunkPool* ChunkPool::_large_pool  = NULL;
 344 ChunkPool* ChunkPool::_medium_pool = NULL;
 345 ChunkPool* ChunkPool::_small_pool  = NULL;
 346 ChunkPool* ChunkPool::_tiny_pool   = NULL;
 347 
 348 void chunkpool_init() {
 349   ChunkPool::initialize();
 350 }
 351 
 352 void
 353 Chunk::clean_chunk_pool() {
 354   ChunkPool::clean();
 355 }
 356 
 357 
 358 //--------------------------------------------------------------------------------------
 359 // ChunkPoolCleaner implementation
 360 //
 361 
 362 class ChunkPoolCleaner : public PeriodicTask {
 363   enum { CleaningInterval = 5000 };      // cleaning interval in ms
 364 
 365  public:
 366    ChunkPoolCleaner() : PeriodicTask(CleaningInterval) {}
 367    void task() {
 368      ChunkPool::clean();
 369    }
 370 };
 371 
 372 //--------------------------------------------------------------------------------------
 373 // Chunk implementation
 374 
 375 void* Chunk::operator new (size_t requested_size, AllocFailType alloc_failmode, size_t length) throw() {
 376   // requested_size is equal to sizeof(Chunk) but in order for the arena
 377   // allocations to come out aligned as expected the size must be aligned
 378   // to expected arena alignment.
 379   // expect requested_size but if sizeof(Chunk) doesn't match isn't proper size we must align it.
 380   assert(ARENA_ALIGN(requested_size) == aligned_overhead_size(), "Bad alignment");
 381   size_t bytes = ARENA_ALIGN(requested_size) + length;
 382   switch (length) {
 383    case Chunk::size:        return ChunkPool::large_pool()->allocate(bytes, alloc_failmode);
 384    case Chunk::medium_size: return ChunkPool::medium_pool()->allocate(bytes, alloc_failmode);
 385    case Chunk::init_size:   return ChunkPool::small_pool()->allocate(bytes, alloc_failmode);
 386    case Chunk::tiny_size:   return ChunkPool::tiny_pool()->allocate(bytes, alloc_failmode);
 387    default: {
 388      void* p = os::malloc(bytes, mtChunk, CALLER_PC);
 389      if (p == NULL && alloc_failmode == AllocFailStrategy::EXIT_OOM) {
 390        vm_exit_out_of_memory(bytes, OOM_MALLOC_ERROR, "Chunk::new");
 391      }
 392      return p;
 393    }
 394   }
 395 }
 396 
 397 void Chunk::operator delete(void* p) {
 398   Chunk* c = (Chunk*)p;
 399   switch (c->length()) {
 400    case Chunk::size:        ChunkPool::large_pool()->free(c); break;
 401    case Chunk::medium_size: ChunkPool::medium_pool()->free(c); break;
 402    case Chunk::init_size:   ChunkPool::small_pool()->free(c); break;
 403    case Chunk::tiny_size:   ChunkPool::tiny_pool()->free(c); break;
 404    default:                 os::free(c, mtChunk);
 405   }
 406 }
 407 
 408 Chunk::Chunk(size_t length) : _len(length) {
 409   _next = NULL;         // Chain on the linked list
 410 }
 411 
 412 
 413 void Chunk::chop() {
 414   Chunk *k = this;
 415   while( k ) {
 416     Chunk *tmp = k->next();
 417     // clear out this chunk (to detect allocation bugs)
 418     if (ZapResourceArea) memset(k->bottom(), badResourceValue, k->length());
 419     delete k;                   // Free chunk (was malloc'd)
 420     k = tmp;
 421   }
 422 }
 423 
 424 void Chunk::next_chop() {
 425   _next->chop();
 426   _next = NULL;
 427 }
 428 
 429 
 430 void Chunk::start_chunk_pool_cleaner_task() {
 431 #ifdef ASSERT
 432   static bool task_created = false;
 433   assert(!task_created, "should not start chuck pool cleaner twice");
 434   task_created = true;
 435 #endif
 436   ChunkPoolCleaner* cleaner = new ChunkPoolCleaner();
 437   cleaner->enroll();
 438 }
 439 
 440 //------------------------------Arena------------------------------------------
 441 NOT_PRODUCT(volatile jint Arena::_instance_count = 0;)
 442 
 443 Arena::Arena(size_t init_size) {
 444   size_t round_size = (sizeof (char *)) - 1;
 445   init_size = (init_size+round_size) & ~round_size;
 446   _first = _chunk = new (AllocFailStrategy::EXIT_OOM, init_size) Chunk(init_size);
 447   _hwm = _chunk->bottom();      // Save the cached hwm, max
 448   _max = _chunk->top();
 449   _size_in_bytes = 0;
 450   set_size_in_bytes(init_size);
 451   NOT_PRODUCT(Atomic::inc(&_instance_count);)
 452 }
 453 
 454 Arena::Arena() {
 455   _first = _chunk = new (AllocFailStrategy::EXIT_OOM, Chunk::init_size) Chunk(Chunk::init_size);
 456   _hwm = _chunk->bottom();      // Save the cached hwm, max
 457   _max = _chunk->top();
 458   _size_in_bytes = 0;
 459   set_size_in_bytes(Chunk::init_size);
 460   NOT_PRODUCT(Atomic::inc(&_instance_count);)
 461 }
 462 
 463 Arena *Arena::move_contents(Arena *copy) {
 464   copy->destruct_contents();
 465   copy->_chunk = _chunk;
 466   copy->_hwm   = _hwm;
 467   copy->_max   = _max;
 468   copy->_first = _first;
 469 
 470   // workaround rare racing condition, which could double count
 471   // the arena size by native memory tracking
 472   size_t size = size_in_bytes();
 473   set_size_in_bytes(0);
 474   copy->set_size_in_bytes(size);
 475   // Destroy original arena
 476   reset();
 477   return copy;            // Return Arena with contents
 478 }
 479 
 480 Arena::~Arena() {
 481   destruct_contents();
 482   NOT_PRODUCT(Atomic::dec(&_instance_count);)
 483 }
 484 
 485 void* Arena::operator new(size_t size) throw() {
 486   assert(false, "Use dynamic memory type binding");
 487   return NULL;
 488 }
 489 
 490 void* Arena::operator new (size_t size, const std::nothrow_t&  nothrow_constant) throw() {
 491   assert(false, "Use dynamic memory type binding");
 492   return NULL;
 493 }
 494 
 495   // dynamic memory type binding
 496 void* Arena::operator new(size_t size, MEMFLAGS flags) throw() {
 497 #ifdef ASSERT
 498   void* p = (void*)AllocateHeap(size, flags|otArena, CALLER_PC);
 499   if (PrintMallocFree) trace_heap_malloc(size, "Arena-new", p);
 500   return p;
 501 #else
 502   return (void *) AllocateHeap(size, flags|otArena, CALLER_PC);
 503 #endif
 504 }
 505 
 506 void* Arena::operator new(size_t size, const std::nothrow_t& nothrow_constant, MEMFLAGS flags) throw() {
 507 #ifdef ASSERT
 508   void* p = os::malloc(size, flags|otArena, CALLER_PC);
 509   if (PrintMallocFree) trace_heap_malloc(size, "Arena-new", p);
 510   return p;
 511 #else
 512   return os::malloc(size, flags|otArena, CALLER_PC);
 513 #endif
 514 }
 515 
 516 void Arena::operator delete(void* p) {
 517   FreeHeap(p);
 518 }
 519 
 520 // Destroy this arenas contents and reset to empty
 521 void Arena::destruct_contents() {
 522   if (UseMallocOnly && _first != NULL) {
 523     char* end = _first->next() ? _first->top() : _hwm;
 524     free_malloced_objects(_first, _first->bottom(), end, _hwm);
 525   }
 526   // reset size before chop to avoid a rare racing condition
 527   // that can have total arena memory exceed total chunk memory
 528   set_size_in_bytes(0);
 529   _first->chop();
 530   reset();
 531 }
 532 
 533 // This is high traffic method, but many calls actually don't
 534 // change the size
 535 void Arena::set_size_in_bytes(size_t size) {
 536   if (_size_in_bytes != size) {
 537     _size_in_bytes = size;
 538     MemTracker::record_arena_size((address)this, size);
 539   }
 540 }
 541 
 542 // Total of all Chunks in arena
 543 size_t Arena::used() const {
 544   size_t sum = _chunk->length() - (_max-_hwm); // Size leftover in this Chunk
 545   register Chunk *k = _first;
 546   while( k != _chunk) {         // Whilst have Chunks in a row
 547     sum += k->length();         // Total size of this Chunk
 548     k = k->next();              // Bump along to next Chunk
 549   }
 550   return sum;                   // Return total consumed space.
 551 }
 552 
 553 void Arena::signal_out_of_memory(size_t sz, const char* whence) const {
 554   vm_exit_out_of_memory(sz, OOM_MALLOC_ERROR, whence);
 555 }
 556 
 557 // Grow a new Chunk
 558 void* Arena::grow(size_t x, AllocFailType alloc_failmode) {
 559   // Get minimal required size.  Either real big, or even bigger for giant objs
 560   size_t len = MAX2(x, (size_t) Chunk::size);
 561 
 562   Chunk *k = _chunk;            // Get filled-up chunk address

 563 
 564   Chunk* tmp_chunk;
 565   tmp_chunk = new (alloc_failmode, len) Chunk(len);
 566   if (tmp_chunk == NULL) {
 567     return NULL;
 568   }
 569   _chunk = tmp_chunk;
 570 
 571   if (k) k->set_next(_chunk);   // Append new chunk to end of linked list
 572   else _first = _chunk;
 573   _hwm  = _chunk->bottom();     // Save the cached hwm, max
 574   _max =  _chunk->top();
 575   set_size_in_bytes(size_in_bytes() + len);
 576   void* result = _hwm;
 577   _hwm += x;
 578   return result;
 579 }
 580 
 581 
 582 
 583 // Reallocate storage in Arena.
 584 void *Arena::Arealloc(void* old_ptr, size_t old_size, size_t new_size, AllocFailType alloc_failmode) {
 585   assert(new_size >= 0, "bad size");
 586   if (new_size == 0) return NULL;
 587 #ifdef ASSERT
 588   if (UseMallocOnly) {
 589     // always allocate a new object  (otherwise we'll free this one twice)
 590     char* copy = (char*)Amalloc(new_size, alloc_failmode);
 591     if (copy == NULL) {
 592       return NULL;
 593     }
 594     size_t n = MIN2(old_size, new_size);
 595     if (n > 0) memcpy(copy, old_ptr, n);
 596     Afree(old_ptr,old_size);    // Mostly done to keep stats accurate
 597     return copy;
 598   }
 599 #endif
 600   char *c_old = (char*)old_ptr; // Handy name
 601   // Stupid fast special case
 602   if( new_size <= old_size ) {  // Shrink in-place
 603     if( c_old+old_size == _hwm) // Attempt to free the excess bytes
 604       _hwm = c_old+new_size;    // Adjust hwm
 605     return c_old;
 606   }
 607 
 608   // make sure that new_size is legal
 609   size_t corrected_new_size = ARENA_ALIGN(new_size);
 610 
 611   // See if we can resize in-place
 612   if( (c_old+old_size == _hwm) &&       // Adjusting recent thing
 613       (c_old+corrected_new_size <= _max) ) {      // Still fits where it sits
 614     _hwm = c_old+corrected_new_size;      // Adjust hwm
 615     return c_old;               // Return old pointer
 616   }
 617 
 618   // Oops, got to relocate guts
 619   void *new_ptr = Amalloc(new_size, alloc_failmode);
 620   if (new_ptr == NULL) {
 621     return NULL;
 622   }
 623   memcpy( new_ptr, c_old, old_size );
 624   Afree(c_old,old_size);        // Mostly done to keep stats accurate
 625   return new_ptr;
 626 }
 627 
 628 
 629 // Determine if pointer belongs to this Arena or not.
 630 bool Arena::contains( const void *ptr ) const {
 631 #ifdef ASSERT
 632   if (UseMallocOnly) {
 633     // really slow, but not easy to make fast
 634     if (_chunk == NULL) return false;
 635     char** bottom = (char**)_chunk->bottom();
 636     for (char** p = (char**)_hwm - 1; p >= bottom; p--) {
 637       if (*p == ptr) return true;
 638     }
 639     for (Chunk *c = _first; c != NULL; c = c->next()) {
 640       if (c == _chunk) continue;  // current chunk has been processed
 641       char** bottom = (char**)c->bottom();
 642       for (char** p = (char**)c->top() - 1; p >= bottom; p--) {
 643         if (*p == ptr) return true;
 644       }
 645     }
 646     return false;
 647   }
 648 #endif
 649   if( (void*)_chunk->bottom() <= ptr && ptr < (void*)_hwm )
 650     return true;                // Check for in this chunk
 651   for (Chunk *c = _first; c; c = c->next()) {
 652     if (c == _chunk) continue;  // current chunk has been processed
 653     if ((void*)c->bottom() <= ptr && ptr < (void*)c->top()) {
 654       return true;              // Check for every chunk in Arena
 655     }
 656   }
 657   return false;                 // Not in any Chunk, so not in Arena
 658 }
 659 
 660 
 661 #ifdef ASSERT
 662 void* Arena::malloc(size_t size) {
 663   assert(UseMallocOnly, "shouldn't call");
 664   // use malloc, but save pointer in res. area for later freeing
 665   char** save = (char**)internal_malloc_4(sizeof(char*));
 666   return (*save = (char*)os::malloc(size, mtChunk));
 667 }
 668 
 669 // for debugging with UseMallocOnly
 670 void* Arena::internal_malloc_4(size_t x) {
 671   assert( (x&(sizeof(char*)-1)) == 0, "misaligned size" );
 672   check_for_overflow(x, "Arena::internal_malloc_4");
 673   if (_hwm + x > _max) {
 674     return grow(x);
 675   } else {
 676     char *old = _hwm;
 677     _hwm += x;
 678     return old;
 679   }
 680 }
 681 #endif
 682 
 683 
 684 //--------------------------------------------------------------------------------------
 685 // Non-product code
 686 
 687 #ifndef PRODUCT
 688 // The global operator new should never be called since it will usually indicate
 689 // a memory leak.  Use CHeapObj as the base class of such objects to make it explicit
 690 // that they're allocated on the C heap.
 691 // Commented out in product version to avoid conflicts with third-party C++ native code.
 692 //
 693 // In C++98/03 the throwing new operators are defined with the following signature:
 694 //
 695 // void* operator new(std::size_tsize) throw(std::bad_alloc);
 696 // void* operator new[](std::size_tsize) throw(std::bad_alloc);
 697 //
 698 // while all the other (non-throwing) new and delete operators are defined with an empty
 699 // throw clause (i.e. "operator delete(void* p) throw()") which means that they do not
 700 // throw any exceptions (see section 18.4 of the C++ standard).
 701 //
 702 // In the new C++11/14 standard, the signature of the throwing new operators was changed
 703 // by completely omitting the throw clause (which effectively means they could throw any
 704 // exception) while all the other new/delete operators where changed to have a 'nothrow'
 705 // clause instead of an empty throw clause.
 706 //
 707 // Unfortunately, the support for exception specifications among C++ compilers is still
 708 // very fragile. While some more strict compilers like AIX xlC or HP aCC reject to
 709 // override the default throwing new operator with a user operator with an empty throw()
 710 // clause, the MS Visual C++ compiler warns for every non-empty throw clause like
 711 // throw(std::bad_alloc) that it will ignore the exception specification. The following
 712 // operator definitions have been checked to correctly work with all currently supported
 713 // compilers and they should be upwards compatible with C++11/14. Therefore
 714 // PLEASE BE CAREFUL if you change the signature of the following operators!
 715 
 716 void* operator new(size_t size) /* throw(std::bad_alloc) */ {
 717   fatal("Should not call global operator new");
 718   return 0;
 719 }
 720 
 721 void* operator new [](size_t size) /* throw(std::bad_alloc) */ {
 722   fatal("Should not call global operator new[]");
 723   return 0;
 724 }
 725 
 726 void* operator new(size_t size, const std::nothrow_t&  nothrow_constant) throw() {
 727   fatal("Should not call global operator new");
 728   return 0;
 729 }
 730 
 731 void* operator new [](size_t size, std::nothrow_t&  nothrow_constant) throw() {
 732   fatal("Should not call global operator new[]");
 733   return 0;
 734 }
 735 
 736 void operator delete(void* p) throw() {
 737   fatal("Should not call global delete");
 738 }
 739 
 740 void operator delete [](void* p) throw() {
 741   fatal("Should not call global delete []");
 742 }
 743 
 744 void AllocatedObj::print() const       { print_on(tty); }
 745 void AllocatedObj::print_value() const { print_value_on(tty); }
 746 
 747 void AllocatedObj::print_on(outputStream* st) const {
 748   st->print_cr("AllocatedObj(" INTPTR_FORMAT ")", p2i(this));
 749 }
 750 
 751 void AllocatedObj::print_value_on(outputStream* st) const {
 752   st->print("AllocatedObj(" INTPTR_FORMAT ")", p2i(this));
 753 }
 754 
 755 julong Arena::_bytes_allocated = 0;
 756 
 757 void Arena::inc_bytes_allocated(size_t x) { inc_stat_counter(&_bytes_allocated, x); }
 758 
 759 AllocStats::AllocStats() {
 760   start_mallocs      = os::num_mallocs;
 761   start_frees        = os::num_frees;
 762   start_malloc_bytes = os::alloc_bytes;
 763   start_mfree_bytes  = os::free_bytes;
 764   start_res_bytes    = Arena::_bytes_allocated;
 765 }
 766 
 767 julong  AllocStats::num_mallocs() { return os::num_mallocs - start_mallocs; }
 768 julong  AllocStats::alloc_bytes() { return os::alloc_bytes - start_malloc_bytes; }
 769 julong  AllocStats::num_frees()   { return os::num_frees - start_frees; }
 770 julong  AllocStats::free_bytes()  { return os::free_bytes - start_mfree_bytes; }
 771 julong  AllocStats::resource_bytes() { return Arena::_bytes_allocated - start_res_bytes; }
 772 void    AllocStats::print() {
 773   tty->print_cr(UINT64_FORMAT " mallocs (" UINT64_FORMAT "MB), "
 774                 UINT64_FORMAT" frees (" UINT64_FORMAT "MB), " UINT64_FORMAT "MB resrc",
 775                 num_mallocs(), alloc_bytes()/M, num_frees(), free_bytes()/M, resource_bytes()/M);
 776 }
 777 
 778 
 779 // debugging code
 780 inline void Arena::free_all(char** start, char** end) {
 781   for (char** p = start; p < end; p++) if (*p) os::free(*p);
 782 }
 783 
 784 void Arena::free_malloced_objects(Chunk* chunk, char* hwm, char* max, char* hwm2) {
 785   assert(UseMallocOnly, "should not call");
 786   // free all objects malloced since resource mark was created; resource area
 787   // contains their addresses
 788   if (chunk->next()) {
 789     // this chunk is full, and some others too
 790     for (Chunk* c = chunk->next(); c != NULL; c = c->next()) {
 791       char* top = c->top();
 792       if (c->next() == NULL) {
 793         top = hwm2;     // last junk is only used up to hwm2
 794         assert(c->contains(hwm2), "bad hwm2");
 795       }
 796       free_all((char**)c->bottom(), (char**)top);
 797     }
 798     assert(chunk->contains(hwm), "bad hwm");
 799     assert(chunk->contains(max), "bad max");
 800     free_all((char**)hwm, (char**)max);
 801   } else {
 802     // this chunk was partially used
 803     assert(chunk->contains(hwm), "bad hwm");
 804     assert(chunk->contains(hwm2), "bad hwm2");
 805     free_all((char**)hwm, (char**)hwm2);
 806   }
 807 }
 808 
 809 
 810 ReallocMark::ReallocMark() {
 811 #ifdef ASSERT
 812   Thread *thread = ThreadLocalStorage::get_thread_slow();
 813   _nesting = thread->resource_area()->nesting();
 814 #endif
 815 }
 816 
 817 void ReallocMark::check() {
 818 #ifdef ASSERT
 819   if (_nesting != Thread::current()->resource_area()->nesting()) {
 820     fatal("allocation bug: array could grow within nested ResourceMark");
 821   }
 822 #endif
 823 }
 824 
 825 #endif // Non-product
--- EOF ---