1 /*
   2  * Copyright (c) 2001, 2013, 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 "classfile/systemDictionary.hpp"
  27 #include "gc_implementation/shared/gcHeapSummary.hpp"
  28 #include "gc_implementation/shared/gcTrace.hpp"
  29 #include "gc_implementation/shared/gcTraceTime.hpp"
  30 #include "gc_implementation/shared/gcWhen.hpp"
  31 #include "gc_implementation/shared/vmGCOperations.hpp"
  32 #include "gc_interface/allocTracer.hpp"
  33 #include "gc_interface/collectedHeap.hpp"
  34 #include "gc_interface/collectedHeap.inline.hpp"
  35 #include "memory/metaspace.hpp"
  36 #include "oops/oop.inline.hpp"
  37 #include "oops/instanceMirrorKlass.hpp"
  38 #include "runtime/init.hpp"
  39 #include "runtime/thread.inline.hpp"
  40 #include "services/heapDumper.hpp"
  41 
  42 
  43 #ifdef ASSERT
  44 int CollectedHeap::_fire_out_of_memory_count = 0;
  45 #endif
  46 
  47 size_t CollectedHeap::_filler_array_max_size = 0;
  48 
  49 template <>
  50 void EventLogBase<GCMessage>::print(outputStream* st, GCMessage& m) {
  51   st->print_cr("GC heap %s", m.is_before ? "before" : "after");
  52   st->print_raw(m);
  53 }
  54 
  55 void GCHeapLog::log_heap(bool before) {
  56   if (!should_log()) {
  57     return;
  58   }
  59 
  60   double timestamp = fetch_timestamp();
  61   MutexLockerEx ml(&_mutex, Mutex::_no_safepoint_check_flag);
  62   int index = compute_log_index();
  63   _records[index].thread = NULL; // Its the GC thread so it's not that interesting.
  64   _records[index].timestamp = timestamp;
  65   _records[index].data.is_before = before;
  66   stringStream st(_records[index].data.buffer(), _records[index].data.size());
  67   if (before) {
  68     Universe::print_heap_before_gc(&st, true);
  69   } else {
  70     Universe::print_heap_after_gc(&st, true);
  71   }
  72 }
  73 
  74 VirtualSpaceSummary CollectedHeap::create_heap_space_summary() {
  75   size_t capacity_in_words = capacity() / HeapWordSize;
  76 
  77   return VirtualSpaceSummary(
  78     reserved_region().start(), reserved_region().start() + capacity_in_words, reserved_region().end());
  79 }
  80 
  81 GCHeapSummary CollectedHeap::create_heap_summary() {
  82   VirtualSpaceSummary heap_space = create_heap_space_summary();
  83   return GCHeapSummary(heap_space, used());
  84 }
  85 
  86 MetaspaceSummary CollectedHeap::create_metaspace_summary() {
  87   const MetaspaceSizes meta_space(
  88       0, /*MetaspaceAux::capacity_in_bytes(),*/
  89       0, /*MetaspaceAux::used_in_bytes(),*/
  90       MetaspaceAux::reserved_in_bytes());
  91   const MetaspaceSizes data_space(
  92       0, /*MetaspaceAux::capacity_in_bytes(Metaspace::NonClassType),*/
  93       0, /*MetaspaceAux::used_in_bytes(Metaspace::NonClassType),*/
  94       MetaspaceAux::reserved_in_bytes(Metaspace::NonClassType));
  95   const MetaspaceSizes class_space(
  96       0, /*MetaspaceAux::capacity_in_bytes(Metaspace::ClassType),*/
  97       0, /*MetaspaceAux::used_in_bytes(Metaspace::ClassType),*/
  98       MetaspaceAux::reserved_in_bytes(Metaspace::ClassType));
  99 
 100   return MetaspaceSummary(meta_space, data_space, class_space);
 101 }
 102 
 103 void CollectedHeap::print_heap_before_gc() {
 104   if (PrintHeapAtGC) {
 105     Universe::print_heap_before_gc();
 106   }
 107   if (_gc_heap_log != NULL) {
 108     _gc_heap_log->log_heap_before();
 109   }
 110 }
 111 
 112 void CollectedHeap::print_heap_after_gc() {
 113   if (PrintHeapAtGC) {
 114     Universe::print_heap_after_gc();
 115   }
 116   if (_gc_heap_log != NULL) {
 117     _gc_heap_log->log_heap_after();
 118   }
 119 }
 120 
 121 void CollectedHeap::trace_heap(GCWhen::Type when, GCTracer* gc_tracer) {
 122   const GCHeapSummary& heap_summary = create_heap_summary();
 123   const MetaspaceSummary& metaspace_summary = create_metaspace_summary();
 124   gc_tracer->report_gc_heap_summary(when, heap_summary, metaspace_summary);
 125 }
 126 
 127 void CollectedHeap::trace_heap_before_gc(GCTracer* gc_tracer) {
 128   trace_heap(GCWhen::BeforeGC, gc_tracer);
 129 }
 130 
 131 void CollectedHeap::trace_heap_after_gc(GCTracer* gc_tracer) {
 132   trace_heap(GCWhen::AfterGC, gc_tracer);
 133 }
 134 
 135 // Memory state functions.
 136 
 137 
 138 CollectedHeap::CollectedHeap() : _n_par_threads(0)
 139 {
 140   const size_t max_len = size_t(arrayOopDesc::max_array_length(T_INT));
 141   const size_t elements_per_word = HeapWordSize / sizeof(jint);
 142   _filler_array_max_size = align_object_size(filler_array_hdr_size() +
 143                                              max_len / elements_per_word);
 144 
 145   _barrier_set = NULL;
 146   _is_gc_active = false;
 147   _total_collections = _total_full_collections = 0;
 148   _gc_cause = _gc_lastcause = GCCause::_no_gc;
 149   NOT_PRODUCT(_promotion_failure_alot_count = 0;)
 150   NOT_PRODUCT(_promotion_failure_alot_gc_number = 0;)
 151 
 152   if (UsePerfData) {
 153     EXCEPTION_MARK;
 154 
 155     // create the gc cause jvmstat counters
 156     _perf_gc_cause = PerfDataManager::create_string_variable(SUN_GC, "cause",
 157                              80, GCCause::to_string(_gc_cause), CHECK);
 158 
 159     _perf_gc_lastcause =
 160                 PerfDataManager::create_string_variable(SUN_GC, "lastCause",
 161                              80, GCCause::to_string(_gc_lastcause), CHECK);
 162   }
 163   _defer_initial_card_mark = false; // strengthened by subclass in pre_initialize() below.
 164   // Create the ring log
 165   if (LogEvents) {
 166     _gc_heap_log = new GCHeapLog();
 167   } else {
 168     _gc_heap_log = NULL;
 169   }
 170 }
 171 
 172 // This interface assumes that it's being called by the
 173 // vm thread. It collects the heap assuming that the
 174 // heap lock is already held and that we are executing in
 175 // the context of the vm thread.
 176 void CollectedHeap::collect_as_vm_thread(GCCause::Cause cause) {
 177   assert(Thread::current()->is_VM_thread(), "Precondition#1");
 178   assert(Heap_lock->is_locked(), "Precondition#2");
 179   GCCauseSetter gcs(this, cause);
 180   switch (cause) {
 181     case GCCause::_heap_inspection:
 182     case GCCause::_heap_dump:
 183     case GCCause::_metadata_GC_threshold : {
 184       HandleMark hm;
 185       do_full_collection(false);        // don't clear all soft refs
 186       break;
 187     }
 188     case GCCause::_last_ditch_collection: {
 189       HandleMark hm;
 190       do_full_collection(true);         // do clear all soft refs
 191       break;
 192     }
 193     default:
 194       ShouldNotReachHere(); // Unexpected use of this function
 195   }
 196 }
 197 MetaWord* CollectedHeap::satisfy_failed_metadata_allocation(
 198                                               ClassLoaderData* loader_data,
 199                                               size_t size, Metaspace::MetadataType mdtype) {
 200   return collector_policy()->satisfy_failed_metadata_allocation(loader_data, size, mdtype);
 201 }
 202 
 203 
 204 void CollectedHeap::pre_initialize() {
 205   // Used for ReduceInitialCardMarks (when COMPILER2 is used);
 206   // otherwise remains unused.
 207 #ifdef COMPILER2
 208   _defer_initial_card_mark =    ReduceInitialCardMarks && can_elide_tlab_store_barriers()
 209                              && (DeferInitialCardMark || card_mark_must_follow_store());
 210 #else
 211   assert(_defer_initial_card_mark == false, "Who would set it?");
 212 #endif
 213 }
 214 
 215 #ifndef PRODUCT
 216 void CollectedHeap::check_for_bad_heap_word_value(HeapWord* addr, size_t size) {
 217   if (CheckMemoryInitialization && ZapUnusedHeapArea) {
 218     for (size_t slot = 0; slot < size; slot += 1) {
 219       assert((*(intptr_t*) (addr + slot)) != ((intptr_t) badHeapWordVal),
 220              "Found badHeapWordValue in post-allocation check");
 221     }
 222   }
 223 }
 224 
 225 void CollectedHeap::check_for_non_bad_heap_word_value(HeapWord* addr, size_t size) {
 226   if (CheckMemoryInitialization && ZapUnusedHeapArea) {
 227     for (size_t slot = 0; slot < size; slot += 1) {
 228       assert((*(intptr_t*) (addr + slot)) == ((intptr_t) badHeapWordVal),
 229              "Found non badHeapWordValue in pre-allocation check");
 230     }
 231   }
 232 }
 233 #endif // PRODUCT
 234 
 235 #ifdef ASSERT
 236 void CollectedHeap::check_for_valid_allocation_state() {
 237   Thread *thread = Thread::current();
 238   // How to choose between a pending exception and a potential
 239   // OutOfMemoryError?  Don't allow pending exceptions.
 240   // This is a VM policy failure, so how do we exhaustively test it?
 241   assert(!thread->has_pending_exception(),
 242          "shouldn't be allocating with pending exception");
 243   if (StrictSafepointChecks) {
 244     assert(thread->allow_allocation(),
 245            "Allocation done by thread for which allocation is blocked "
 246            "by No_Allocation_Verifier!");
 247     // Allocation of an oop can always invoke a safepoint,
 248     // hence, the true argument
 249     thread->check_for_valid_safepoint_state(true);
 250   }
 251 }
 252 #endif
 253 
 254 HeapWord* CollectedHeap::allocate_from_tlab_slow(KlassHandle klass, Thread* thread, size_t size) {
 255 
 256   // Retain tlab and allocate object in shared space if
 257   // the amount free in the tlab is too large to discard.
 258   if (thread->tlab().free() > thread->tlab().refill_waste_limit()) {
 259     thread->tlab().record_slow_allocation(size);
 260     return NULL;
 261   }
 262 
 263   // Discard tlab and allocate a new one.
 264   // To minimize fragmentation, the last TLAB may be smaller than the rest.
 265   size_t new_tlab_size = thread->tlab().compute_size(size);
 266 
 267   thread->tlab().clear_before_allocation();
 268 
 269   if (new_tlab_size == 0) {
 270     return NULL;
 271   }
 272 
 273   // Allocate a new TLAB...
 274   HeapWord* obj = Universe::heap()->allocate_new_tlab(new_tlab_size);
 275   if (obj == NULL) {
 276     return NULL;
 277   }
 278 
 279   AllocTracer::send_allocation_in_new_tlab_event(klass, new_tlab_size * HeapWordSize, size * HeapWordSize);
 280 
 281   if (ZeroTLAB) {
 282     // ..and clear it.
 283     Copy::zero_to_words(obj, new_tlab_size);
 284   } else {
 285     // ...and zap just allocated object.
 286 #ifdef ASSERT
 287     // Skip mangling the space corresponding to the object header to
 288     // ensure that the returned space is not considered parsable by
 289     // any concurrent GC thread.
 290     size_t hdr_size = oopDesc::header_size();
 291     Copy::fill_to_words(obj + hdr_size, new_tlab_size - hdr_size, badHeapWordVal);
 292 #endif // ASSERT
 293   }
 294   thread->tlab().fill(obj, obj + size, new_tlab_size);
 295   return obj;
 296 }
 297 
 298 void CollectedHeap::flush_deferred_store_barrier(JavaThread* thread) {
 299   MemRegion deferred = thread->deferred_card_mark();
 300   if (!deferred.is_empty()) {
 301     assert(_defer_initial_card_mark, "Otherwise should be empty");
 302     {
 303       // Verify that the storage points to a parsable object in heap
 304       DEBUG_ONLY(oop old_obj = oop(deferred.start());)
 305       assert(is_in(old_obj), "Not in allocated heap");
 306       assert(!can_elide_initializing_store_barrier(old_obj),
 307              "Else should have been filtered in new_store_pre_barrier()");
 308       assert(old_obj->is_oop(true), "Not an oop");
 309       assert(deferred.word_size() == (size_t)(old_obj->size()),
 310              "Mismatch: multiple objects?");
 311     }
 312     BarrierSet* bs = barrier_set();
 313     assert(bs->has_write_region_opt(), "No write_region() on BarrierSet");
 314     bs->write_region(deferred);
 315     // "Clear" the deferred_card_mark field
 316     thread->set_deferred_card_mark(MemRegion());
 317   }
 318   assert(thread->deferred_card_mark().is_empty(), "invariant");
 319 }
 320 
 321 // Helper for ReduceInitialCardMarks. For performance,
 322 // compiled code may elide card-marks for initializing stores
 323 // to a newly allocated object along the fast-path. We
 324 // compensate for such elided card-marks as follows:
 325 // (a) Generational, non-concurrent collectors, such as
 326 //     GenCollectedHeap(ParNew,DefNew,Tenured) and
 327 //     ParallelScavengeHeap(ParallelGC, ParallelOldGC)
 328 //     need the card-mark if and only if the region is
 329 //     in the old gen, and do not care if the card-mark
 330 //     succeeds or precedes the initializing stores themselves,
 331 //     so long as the card-mark is completed before the next
 332 //     scavenge. For all these cases, we can do a card mark
 333 //     at the point at which we do a slow path allocation
 334 //     in the old gen, i.e. in this call.
 335 // (b) GenCollectedHeap(ConcurrentMarkSweepGeneration) requires
 336 //     in addition that the card-mark for an old gen allocated
 337 //     object strictly follow any associated initializing stores.
 338 //     In these cases, the memRegion remembered below is
 339 //     used to card-mark the entire region either just before the next
 340 //     slow-path allocation by this thread or just before the next scavenge or
 341 //     CMS-associated safepoint, whichever of these events happens first.
 342 //     (The implicit assumption is that the object has been fully
 343 //     initialized by this point, a fact that we assert when doing the
 344 //     card-mark.)
 345 // (c) G1CollectedHeap(G1) uses two kinds of write barriers. When a
 346 //     G1 concurrent marking is in progress an SATB (pre-write-)barrier is
 347 //     is used to remember the pre-value of any store. Initializing
 348 //     stores will not need this barrier, so we need not worry about
 349 //     compensating for the missing pre-barrier here. Turning now
 350 //     to the post-barrier, we note that G1 needs a RS update barrier
 351 //     which simply enqueues a (sequence of) dirty cards which may
 352 //     optionally be refined by the concurrent update threads. Note
 353 //     that this barrier need only be applied to a non-young write,
 354 //     but, like in CMS, because of the presence of concurrent refinement
 355 //     (much like CMS' precleaning), must strictly follow the oop-store.
 356 //     Thus, using the same protocol for maintaining the intended
 357 //     invariants turns out, serendepitously, to be the same for both
 358 //     G1 and CMS.
 359 //
 360 // For any future collector, this code should be reexamined with
 361 // that specific collector in mind, and the documentation above suitably
 362 // extended and updated.
 363 oop CollectedHeap::new_store_pre_barrier(JavaThread* thread, oop new_obj) {
 364   // If a previous card-mark was deferred, flush it now.
 365   flush_deferred_store_barrier(thread);
 366   if (can_elide_initializing_store_barrier(new_obj)) {
 367     // The deferred_card_mark region should be empty
 368     // following the flush above.
 369     assert(thread->deferred_card_mark().is_empty(), "Error");
 370   } else {
 371     MemRegion mr((HeapWord*)new_obj, new_obj->size());
 372     assert(!mr.is_empty(), "Error");
 373     if (_defer_initial_card_mark) {
 374       // Defer the card mark
 375       thread->set_deferred_card_mark(mr);
 376     } else {
 377       // Do the card mark
 378       BarrierSet* bs = barrier_set();
 379       assert(bs->has_write_region_opt(), "No write_region() on BarrierSet");
 380       bs->write_region(mr);
 381     }
 382   }
 383   return new_obj;
 384 }
 385 
 386 size_t CollectedHeap::filler_array_hdr_size() {
 387   return size_t(align_object_offset(arrayOopDesc::header_size(T_INT))); // align to Long
 388 }
 389 
 390 size_t CollectedHeap::filler_array_min_size() {
 391   return align_object_size(filler_array_hdr_size()); // align to MinObjAlignment
 392 }
 393 
 394 #ifdef ASSERT
 395 void CollectedHeap::fill_args_check(HeapWord* start, size_t words)
 396 {
 397   assert(words >= min_fill_size(), "too small to fill");
 398   assert(words % MinObjAlignment == 0, "unaligned size");
 399   assert(Universe::heap()->is_in_reserved(start), "not in heap");
 400   assert(Universe::heap()->is_in_reserved(start + words - 1), "not in heap");
 401 }
 402 
 403 void CollectedHeap::zap_filler_array(HeapWord* start, size_t words, bool zap)
 404 {
 405   if (ZapFillerObjects && zap) {
 406     Copy::fill_to_words(start + filler_array_hdr_size(),
 407                         words - filler_array_hdr_size(), 0XDEAFBABE);
 408   }
 409 }
 410 #endif // ASSERT
 411 
 412 void
 413 CollectedHeap::fill_with_array(HeapWord* start, size_t words, bool zap)
 414 {
 415   assert(words >= filler_array_min_size(), "too small for an array");
 416   assert(words <= filler_array_max_size(), "too big for a single object");
 417 
 418   const size_t payload_size = words - filler_array_hdr_size();
 419   const size_t len = payload_size * HeapWordSize / sizeof(jint);
 420   assert((int)len >= 0, err_msg("size too large " SIZE_FORMAT " becomes %d", words, (int)len));
 421 
 422   // Set the length first for concurrent GC.
 423   ((arrayOop)start)->set_length((int)len);
 424   post_allocation_setup_common(Universe::intArrayKlassObj(), start);
 425   DEBUG_ONLY(zap_filler_array(start, words, zap);)
 426 }
 427 
 428 void
 429 CollectedHeap::fill_with_object_impl(HeapWord* start, size_t words, bool zap)
 430 {
 431   assert(words <= filler_array_max_size(), "too big for a single object");
 432 
 433   if (words >= filler_array_min_size()) {
 434     fill_with_array(start, words, zap);
 435   } else if (words > 0) {
 436     assert(words == min_fill_size(), "unaligned size");
 437     post_allocation_setup_common(SystemDictionary::Object_klass(), start);
 438   }
 439 }
 440 
 441 void CollectedHeap::fill_with_object(HeapWord* start, size_t words, bool zap)
 442 {
 443   DEBUG_ONLY(fill_args_check(start, words);)
 444   HandleMark hm;  // Free handles before leaving.
 445   fill_with_object_impl(start, words, zap);
 446 }
 447 
 448 void CollectedHeap::fill_with_objects(HeapWord* start, size_t words, bool zap)
 449 {
 450   DEBUG_ONLY(fill_args_check(start, words);)
 451   HandleMark hm;  // Free handles before leaving.
 452 
 453 #ifdef _LP64
 454   // A single array can fill ~8G, so multiple objects are needed only in 64-bit.
 455   // First fill with arrays, ensuring that any remaining space is big enough to
 456   // fill.  The remainder is filled with a single object.
 457   const size_t min = min_fill_size();
 458   const size_t max = filler_array_max_size();
 459   while (words > max) {
 460     const size_t cur = words - max >= min ? max : max - min;
 461     fill_with_array(start, cur, zap);
 462     start += cur;
 463     words -= cur;
 464   }
 465 #endif
 466 
 467   fill_with_object_impl(start, words, zap);
 468 }
 469 
 470 HeapWord* CollectedHeap::allocate_new_tlab(size_t size) {
 471   guarantee(false, "thread-local allocation buffers not supported");
 472   return NULL;
 473 }
 474 
 475 void CollectedHeap::ensure_parsability(bool retire_tlabs) {
 476   // The second disjunct in the assertion below makes a concession
 477   // for the start-up verification done while the VM is being
 478   // created. Callers be careful that you know that mutators
 479   // aren't going to interfere -- for instance, this is permissible
 480   // if we are still single-threaded and have either not yet
 481   // started allocating (nothing much to verify) or we have
 482   // started allocating but are now a full-fledged JavaThread
 483   // (and have thus made our TLAB's) available for filling.
 484   assert(SafepointSynchronize::is_at_safepoint() ||
 485          !is_init_completed(),
 486          "Should only be called at a safepoint or at start-up"
 487          " otherwise concurrent mutator activity may make heap "
 488          " unparsable again");
 489   const bool use_tlab = UseTLAB;
 490   const bool deferred = _defer_initial_card_mark;
 491   // The main thread starts allocating via a TLAB even before it
 492   // has added itself to the threads list at vm boot-up.
 493   assert(!use_tlab || Threads::first() != NULL,
 494          "Attempt to fill tlabs before main thread has been added"
 495          " to threads list is doomed to failure!");
 496   for (JavaThread *thread = Threads::first(); thread; thread = thread->next()) {
 497      if (use_tlab) thread->tlab().make_parsable(retire_tlabs);
 498 #ifdef COMPILER2
 499      // The deferred store barriers must all have been flushed to the
 500      // card-table (or other remembered set structure) before GC starts
 501      // processing the card-table (or other remembered set).
 502      if (deferred) flush_deferred_store_barrier(thread);
 503 #else
 504      assert(!deferred, "Should be false");
 505      assert(thread->deferred_card_mark().is_empty(), "Should be empty");
 506 #endif
 507   }
 508 }
 509 
 510 void CollectedHeap::accumulate_statistics_all_tlabs() {
 511   if (UseTLAB) {
 512     assert(SafepointSynchronize::is_at_safepoint() ||
 513          !is_init_completed(),
 514          "should only accumulate statistics on tlabs at safepoint");
 515 
 516     ThreadLocalAllocBuffer::accumulate_statistics_before_gc();
 517   }
 518 }
 519 
 520 void CollectedHeap::resize_all_tlabs() {
 521   if (UseTLAB) {
 522     assert(SafepointSynchronize::is_at_safepoint() ||
 523          !is_init_completed(),
 524          "should only resize tlabs at safepoint");
 525 
 526     ThreadLocalAllocBuffer::resize_all_tlabs();
 527   }
 528 }
 529 
 530 void CollectedHeap::pre_full_gc_dump(GCTimer* timer) {
 531   if (HeapDumpBeforeFullGC) {
 532     GCTraceTime tt("Heap Dump (before full gc): ", PrintGCDetails, false, timer);
 533     // We are doing a "major" collection and a heap dump before
 534     // major collection has been requested.
 535     HeapDumper::dump_heap();
 536   }
 537   if (PrintClassHistogramBeforeFullGC) {
 538     GCTraceTime tt("Class Histogram (before full gc): ", PrintGCDetails, true, timer);
 539     VM_GC_HeapInspection inspector(gclog_or_tty, false /* ! full gc */);
 540     inspector.doit();
 541   }
 542 }
 543 
 544 void CollectedHeap::post_full_gc_dump(GCTimer* timer) {
 545   if (HeapDumpAfterFullGC) {
 546     GCTraceTime tt("Heap Dump (after full gc): ", PrintGCDetails, false, timer);
 547     HeapDumper::dump_heap();
 548   }
 549   if (PrintClassHistogramAfterFullGC) {
 550     GCTraceTime tt("Class Histogram (after full gc): ", PrintGCDetails, true, timer);
 551     VM_GC_HeapInspection inspector(gclog_or_tty, false /* ! full gc */);
 552     inspector.doit();
 553   }
 554 }
 555 
 556 oop CollectedHeap::Class_obj_allocate(KlassHandle klass, int size, KlassHandle real_klass, TRAPS) {
 557   debug_only(check_for_valid_allocation_state());
 558   assert(!Universe::heap()->is_gc_active(), "Allocation during gc not allowed");
 559   assert(size >= 0, "int won't convert to size_t");
 560   HeapWord* obj;
 561     assert(ScavengeRootsInCode > 0, "must be");
 562     obj = common_mem_allocate_init(real_klass, size, CHECK_NULL);
 563   post_allocation_setup_common(klass, obj);
 564   assert(Universe::is_bootstrapping() ||
 565          !((oop)obj)->is_array(), "must not be an array");
 566   NOT_PRODUCT(Universe::heap()->check_for_bad_heap_word_value(obj, size));
 567   oop mirror = (oop)obj;
 568 
 569   java_lang_Class::set_oop_size(mirror, size);
 570 
 571   // Setup indirections
 572   if (!real_klass.is_null()) {
 573     java_lang_Class::set_klass(mirror, real_klass());
 574     real_klass->set_java_mirror(mirror);
 575   }
 576 
 577   InstanceMirrorKlass* mk = InstanceMirrorKlass::cast(mirror->klass());
 578   assert(size == mk->instance_size(real_klass), "should have been set");
 579 
 580   // notify jvmti and dtrace
 581   post_allocation_notify(klass, (oop)obj);
 582 
 583   return mirror;
 584 }
 585 
 586 /////////////// Unit tests ///////////////
 587 
 588 #ifndef PRODUCT
 589 void CollectedHeap::test_is_in() {
 590   CollectedHeap* heap = Universe::heap();
 591 
 592   uintptr_t epsilon    = (uintptr_t) MinObjAlignment;
 593   uintptr_t heap_start = (uintptr_t) heap->_reserved.start();
 594   uintptr_t heap_end   = (uintptr_t) heap->_reserved.end();
 595 
 596   // Test that NULL is not in the heap.
 597   assert(!heap->is_in(NULL), "NULL is unexpectedly in the heap");
 598 
 599   // Test that a pointer to before the heap start is reported as outside the heap.
 600   assert(heap_start >= ((uintptr_t)NULL + epsilon), "sanity");
 601   void* before_heap = (void*)(heap_start - epsilon);
 602   assert(!heap->is_in(before_heap),
 603       err_msg("before_heap: " PTR_FORMAT " is unexpectedly in the heap", before_heap));
 604 
 605   // Test that a pointer to after the heap end is reported as outside the heap.
 606   assert(heap_end <= ((uintptr_t)-1 - epsilon), "sanity");
 607   void* after_heap = (void*)(heap_end + epsilon);
 608   assert(!heap->is_in(after_heap),
 609       err_msg("after_heap: " PTR_FORMAT " is unexpectedly in the heap", after_heap));
 610 }
 611 #endif