rev 48000 : [mq]: open.patch
rev 48001 : [mq]: 8191564-diff.patch

   1 /*
   2  * Copyright (c) 2001, 2017, 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 "code/codeCache.hpp"
  27 #include "gc/parallel/adjoiningGenerations.hpp"
  28 #include "gc/parallel/adjoiningVirtualSpaces.hpp"
  29 #include "gc/parallel/cardTableExtension.hpp"
  30 #include "gc/parallel/gcTaskManager.hpp"
  31 #include "gc/parallel/generationSizer.hpp"
  32 #include "gc/parallel/objectStartArray.inline.hpp"
  33 #include "gc/parallel/parallelScavengeHeap.inline.hpp"
  34 #include "gc/parallel/psAdaptiveSizePolicy.hpp"
  35 #include "gc/parallel/psMarkSweep.hpp"
  36 #include "gc/parallel/psMemoryPool.hpp"
  37 #include "gc/parallel/psParallelCompact.inline.hpp"
  38 #include "gc/parallel/psPromotionManager.hpp"
  39 #include "gc/parallel/psScavenge.hpp"
  40 #include "gc/parallel/vmPSOperations.hpp"
  41 #include "gc/shared/gcHeapSummary.hpp"
  42 #include "gc/shared/gcLocker.inline.hpp"
  43 #include "gc/shared/gcWhen.hpp"
  44 #include "logging/log.hpp"
  45 #include "oops/oop.inline.hpp"
  46 #include "runtime/handles.inline.hpp"
  47 #include "runtime/java.hpp"
  48 #include "runtime/vmThread.hpp"
  49 #include "services/memoryManager.hpp"
  50 #include "services/memTracker.hpp"
  51 #include "utilities/vmError.hpp"
  52 
  53 PSYoungGen*  ParallelScavengeHeap::_young_gen = NULL;
  54 PSOldGen*    ParallelScavengeHeap::_old_gen = NULL;
  55 PSAdaptiveSizePolicy* ParallelScavengeHeap::_size_policy = NULL;
  56 PSGCAdaptivePolicyCounters* ParallelScavengeHeap::_gc_policy_counters = NULL;
  57 GCTaskManager* ParallelScavengeHeap::_gc_task_manager = NULL;
  58 
  59 jint ParallelScavengeHeap::initialize() {
  60   CollectedHeap::pre_initialize();
  61 
  62   const size_t heap_size = _collector_policy->max_heap_byte_size();
  63 
  64   ReservedSpace heap_rs = Universe::reserve_heap(heap_size, _collector_policy->heap_alignment());
  65 
  66   os::trace_page_sizes("Heap",
  67                        _collector_policy->min_heap_byte_size(),
  68                        heap_size,
  69                        generation_alignment(),
  70                        heap_rs.base(),
  71                        heap_rs.size());
  72 
  73   initialize_reserved_region((HeapWord*)heap_rs.base(), (HeapWord*)(heap_rs.base() + heap_rs.size()));
  74 
  75   CardTableExtension* const barrier_set = new CardTableExtension(reserved_region());
  76   barrier_set->initialize();
  77   set_barrier_set(barrier_set);
  78 
  79   // Make up the generations
  80   // Calculate the maximum size that a generation can grow.  This
  81   // includes growth into the other generation.  Note that the
  82   // parameter _max_gen_size is kept as the maximum
  83   // size of the generation as the boundaries currently stand.
  84   // _max_gen_size is still used as that value.
  85   double max_gc_pause_sec = ((double) MaxGCPauseMillis)/1000.0;
  86   double max_gc_minor_pause_sec = ((double) MaxGCMinorPauseMillis)/1000.0;
  87 
  88   _gens = new AdjoiningGenerations(heap_rs, _collector_policy, generation_alignment());
  89 
  90   _old_gen = _gens->old_gen();
  91   _young_gen = _gens->young_gen();
  92 
  93   const size_t eden_capacity = _young_gen->eden_space()->capacity_in_bytes();
  94   const size_t old_capacity = _old_gen->capacity_in_bytes();
  95   const size_t initial_promo_size = MIN2(eden_capacity, old_capacity);
  96   _size_policy =
  97     new PSAdaptiveSizePolicy(eden_capacity,
  98                              initial_promo_size,
  99                              young_gen()->to_space()->capacity_in_bytes(),
 100                              _collector_policy->gen_alignment(),
 101                              max_gc_pause_sec,
 102                              max_gc_minor_pause_sec,
 103                              GCTimeRatio
 104                              );
 105 
 106   assert(!UseAdaptiveGCBoundary ||
 107     (old_gen()->virtual_space()->high_boundary() ==
 108      young_gen()->virtual_space()->low_boundary()),
 109     "Boundaries must meet");
 110   // initialize the policy counters - 2 collectors, 2 generations
 111   _gc_policy_counters =
 112     new PSGCAdaptivePolicyCounters("ParScav:MSC", 2, 2, _size_policy);
 113 
 114   // Set up the GCTaskManager
 115   _gc_task_manager = GCTaskManager::create(ParallelGCThreads);
 116 
 117   if (UseParallelOldGC && !PSParallelCompact::initialize()) {
 118     return JNI_ENOMEM;
 119   }
 120 




 121 
 122   _eden_pool = new EdenMutableSpacePool(_young_gen,
 123                                         _young_gen->eden_space(),
 124                                         "PS Eden Space",
 125                                         false /* support_usage_threshold */);
 126 
 127   _survivor_pool = new SurvivorMutableSpacePool(_young_gen,
 128                                                 "PS Survivor Space",
 129                                                 false /* support_usage_threshold */);
 130 
 131   _old_pool = new PSGenerationPool(_old_gen,
 132                                    "PS Old Gen",
 133                                    true /* support_usage_threshold */);
 134 
 135   _young_manager = new GCMemoryManager("PS Scavenge", "end of minor GC");
 136   _old_manager = new GCMemoryManager("PS MarkSweep", "end of major GC");
 137 
 138   _old_manager->add_pool(_eden_pool);
 139   _old_manager->add_pool(_survivor_pool);
 140   _old_manager->add_pool(_old_pool);
 141 
 142   _young_manager->add_pool(_eden_pool);
 143   _young_manager->add_pool(_survivor_pool);
 144 
 145   return JNI_OK;
 146 }
 147 
 148 void ParallelScavengeHeap::post_initialize() {

 149   // Need to init the tenuring threshold
 150   PSScavenge::initialize();
 151   if (UseParallelOldGC) {
 152     PSParallelCompact::post_initialize();
 153   } else {
 154     PSMarkSweep::initialize();
 155   }
 156   PSPromotionManager::initialize();
 157 }
 158 
 159 void ParallelScavengeHeap::update_counters() {
 160   young_gen()->update_counters();
 161   old_gen()->update_counters();
 162   MetaspaceCounters::update_performance_counters();
 163   CompressedClassSpaceCounters::update_performance_counters();
 164 }
 165 
 166 size_t ParallelScavengeHeap::capacity() const {
 167   size_t value = young_gen()->capacity_in_bytes() + old_gen()->capacity_in_bytes();
 168   return value;
 169 }
 170 
 171 size_t ParallelScavengeHeap::used() const {
 172   size_t value = young_gen()->used_in_bytes() + old_gen()->used_in_bytes();
 173   return value;
 174 }
 175 
 176 bool ParallelScavengeHeap::is_maximal_no_gc() const {
 177   return old_gen()->is_maximal_no_gc() && young_gen()->is_maximal_no_gc();
 178 }
 179 
 180 
 181 size_t ParallelScavengeHeap::max_capacity() const {
 182   size_t estimated = reserved_region().byte_size();
 183   if (UseAdaptiveSizePolicy) {
 184     estimated -= _size_policy->max_survivor_size(young_gen()->max_size());
 185   } else {
 186     estimated -= young_gen()->to_space()->capacity_in_bytes();
 187   }
 188   return MAX2(estimated, capacity());
 189 }
 190 
 191 bool ParallelScavengeHeap::is_in(const void* p) const {
 192   return young_gen()->is_in(p) || old_gen()->is_in(p);
 193 }
 194 
 195 bool ParallelScavengeHeap::is_in_reserved(const void* p) const {
 196   return young_gen()->is_in_reserved(p) || old_gen()->is_in_reserved(p);
 197 }
 198 
 199 // There are two levels of allocation policy here.
 200 //
 201 // When an allocation request fails, the requesting thread must invoke a VM
 202 // operation, transfer control to the VM thread, and await the results of a
 203 // garbage collection. That is quite expensive, and we should avoid doing it
 204 // multiple times if possible.
 205 //
 206 // To accomplish this, we have a basic allocation policy, and also a
 207 // failed allocation policy.
 208 //
 209 // The basic allocation policy controls how you allocate memory without
 210 // attempting garbage collection. It is okay to grab locks and
 211 // expand the heap, if that can be done without coming to a safepoint.
 212 // It is likely that the basic allocation policy will not be very
 213 // aggressive.
 214 //
 215 // The failed allocation policy is invoked from the VM thread after
 216 // the basic allocation policy is unable to satisfy a mem_allocate
 217 // request. This policy needs to cover the entire range of collection,
 218 // heap expansion, and out-of-memory conditions. It should make every
 219 // attempt to allocate the requested memory.
 220 
 221 // Basic allocation policy. Should never be called at a safepoint, or
 222 // from the VM thread.
 223 //
 224 // This method must handle cases where many mem_allocate requests fail
 225 // simultaneously. When that happens, only one VM operation will succeed,
 226 // and the rest will not be executed. For that reason, this method loops
 227 // during failed allocation attempts. If the java heap becomes exhausted,
 228 // we rely on the size_policy object to force a bail out.
 229 HeapWord* ParallelScavengeHeap::mem_allocate(
 230                                      size_t size,
 231                                      bool* gc_overhead_limit_was_exceeded) {
 232   assert(!SafepointSynchronize::is_at_safepoint(), "should not be at safepoint");
 233   assert(Thread::current() != (Thread*)VMThread::vm_thread(), "should not be in vm thread");
 234   assert(!Heap_lock->owned_by_self(), "this thread should not own the Heap_lock");
 235 
 236   // In general gc_overhead_limit_was_exceeded should be false so
 237   // set it so here and reset it to true only if the gc time
 238   // limit is being exceeded as checked below.
 239   *gc_overhead_limit_was_exceeded = false;
 240 
 241   HeapWord* result = young_gen()->allocate(size);
 242 
 243   uint loop_count = 0;
 244   uint gc_count = 0;
 245   uint gclocker_stalled_count = 0;
 246 
 247   while (result == NULL) {
 248     // We don't want to have multiple collections for a single filled generation.
 249     // To prevent this, each thread tracks the total_collections() value, and if
 250     // the count has changed, does not do a new collection.
 251     //
 252     // The collection count must be read only while holding the heap lock. VM
 253     // operations also hold the heap lock during collections. There is a lock
 254     // contention case where thread A blocks waiting on the Heap_lock, while
 255     // thread B is holding it doing a collection. When thread A gets the lock,
 256     // the collection count has already changed. To prevent duplicate collections,
 257     // The policy MUST attempt allocations during the same period it reads the
 258     // total_collections() value!
 259     {
 260       MutexLocker ml(Heap_lock);
 261       gc_count = total_collections();
 262 
 263       result = young_gen()->allocate(size);
 264       if (result != NULL) {
 265         return result;
 266       }
 267 
 268       // If certain conditions hold, try allocating from the old gen.
 269       result = mem_allocate_old_gen(size);
 270       if (result != NULL) {
 271         return result;
 272       }
 273 
 274       if (gclocker_stalled_count > GCLockerRetryAllocationCount) {
 275         return NULL;
 276       }
 277 
 278       // Failed to allocate without a gc.
 279       if (GCLocker::is_active_and_needs_gc()) {
 280         // If this thread is not in a jni critical section, we stall
 281         // the requestor until the critical section has cleared and
 282         // GC allowed. When the critical section clears, a GC is
 283         // initiated by the last thread exiting the critical section; so
 284         // we retry the allocation sequence from the beginning of the loop,
 285         // rather than causing more, now probably unnecessary, GC attempts.
 286         JavaThread* jthr = JavaThread::current();
 287         if (!jthr->in_critical()) {
 288           MutexUnlocker mul(Heap_lock);
 289           GCLocker::stall_until_clear();
 290           gclocker_stalled_count += 1;
 291           continue;
 292         } else {
 293           if (CheckJNICalls) {
 294             fatal("Possible deadlock due to allocating while"
 295                   " in jni critical section");
 296           }
 297           return NULL;
 298         }
 299       }
 300     }
 301 
 302     if (result == NULL) {
 303       // Generate a VM operation
 304       VM_ParallelGCFailedAllocation op(size, gc_count);
 305       VMThread::execute(&op);
 306 
 307       // Did the VM operation execute? If so, return the result directly.
 308       // This prevents us from looping until time out on requests that can
 309       // not be satisfied.
 310       if (op.prologue_succeeded()) {
 311         assert(is_in_or_null(op.result()), "result not in heap");
 312 
 313         // If GC was locked out during VM operation then retry allocation
 314         // and/or stall as necessary.
 315         if (op.gc_locked()) {
 316           assert(op.result() == NULL, "must be NULL if gc_locked() is true");
 317           continue;  // retry and/or stall as necessary
 318         }
 319 
 320         // Exit the loop if the gc time limit has been exceeded.
 321         // The allocation must have failed above ("result" guarding
 322         // this path is NULL) and the most recent collection has exceeded the
 323         // gc overhead limit (although enough may have been collected to
 324         // satisfy the allocation).  Exit the loop so that an out-of-memory
 325         // will be thrown (return a NULL ignoring the contents of
 326         // op.result()),
 327         // but clear gc_overhead_limit_exceeded so that the next collection
 328         // starts with a clean slate (i.e., forgets about previous overhead
 329         // excesses).  Fill op.result() with a filler object so that the
 330         // heap remains parsable.
 331         const bool limit_exceeded = size_policy()->gc_overhead_limit_exceeded();
 332         const bool softrefs_clear = collector_policy()->all_soft_refs_clear();
 333 
 334         if (limit_exceeded && softrefs_clear) {
 335           *gc_overhead_limit_was_exceeded = true;
 336           size_policy()->set_gc_overhead_limit_exceeded(false);
 337           log_trace(gc)("ParallelScavengeHeap::mem_allocate: return NULL because gc_overhead_limit_exceeded is set");
 338           if (op.result() != NULL) {
 339             CollectedHeap::fill_with_object(op.result(), size);
 340           }
 341           return NULL;
 342         }
 343 
 344         return op.result();
 345       }
 346     }
 347 
 348     // The policy object will prevent us from looping forever. If the
 349     // time spent in gc crosses a threshold, we will bail out.
 350     loop_count++;
 351     if ((result == NULL) && (QueuedAllocationWarningCount > 0) &&
 352         (loop_count % QueuedAllocationWarningCount == 0)) {
 353       log_warning(gc)("ParallelScavengeHeap::mem_allocate retries %d times", loop_count);
 354       log_warning(gc)("\tsize=" SIZE_FORMAT, size);
 355     }
 356   }
 357 
 358   return result;
 359 }
 360 
 361 // A "death march" is a series of ultra-slow allocations in which a full gc is
 362 // done before each allocation, and after the full gc the allocation still
 363 // cannot be satisfied from the young gen.  This routine detects that condition;
 364 // it should be called after a full gc has been done and the allocation
 365 // attempted from the young gen. The parameter 'addr' should be the result of
 366 // that young gen allocation attempt.
 367 void
 368 ParallelScavengeHeap::death_march_check(HeapWord* const addr, size_t size) {
 369   if (addr != NULL) {
 370     _death_march_count = 0;  // death march has ended
 371   } else if (_death_march_count == 0) {
 372     if (should_alloc_in_eden(size)) {
 373       _death_march_count = 1;    // death march has started
 374     }
 375   }
 376 }
 377 
 378 HeapWord* ParallelScavengeHeap::mem_allocate_old_gen(size_t size) {
 379   if (!should_alloc_in_eden(size) || GCLocker::is_active_and_needs_gc()) {
 380     // Size is too big for eden, or gc is locked out.
 381     return old_gen()->allocate(size);
 382   }
 383 
 384   // If a "death march" is in progress, allocate from the old gen a limited
 385   // number of times before doing a GC.
 386   if (_death_march_count > 0) {
 387     if (_death_march_count < 64) {
 388       ++_death_march_count;
 389       return old_gen()->allocate(size);
 390     } else {
 391       _death_march_count = 0;
 392     }
 393   }
 394   return NULL;
 395 }
 396 
 397 void ParallelScavengeHeap::do_full_collection(bool clear_all_soft_refs) {
 398   if (UseParallelOldGC) {
 399     // The do_full_collection() parameter clear_all_soft_refs
 400     // is interpreted here as maximum_compaction which will
 401     // cause SoftRefs to be cleared.
 402     bool maximum_compaction = clear_all_soft_refs;
 403     PSParallelCompact::invoke(maximum_compaction);
 404   } else {
 405     PSMarkSweep::invoke(clear_all_soft_refs);
 406   }
 407 }
 408 
 409 // Failed allocation policy. Must be called from the VM thread, and
 410 // only at a safepoint! Note that this method has policy for allocation
 411 // flow, and NOT collection policy. So we do not check for gc collection
 412 // time over limit here, that is the responsibility of the heap specific
 413 // collection methods. This method decides where to attempt allocations,
 414 // and when to attempt collections, but no collection specific policy.
 415 HeapWord* ParallelScavengeHeap::failed_mem_allocate(size_t size) {
 416   assert(SafepointSynchronize::is_at_safepoint(), "should be at safepoint");
 417   assert(Thread::current() == (Thread*)VMThread::vm_thread(), "should be in vm thread");
 418   assert(!is_gc_active(), "not reentrant");
 419   assert(!Heap_lock->owned_by_self(), "this thread should not own the Heap_lock");
 420 
 421   // We assume that allocation in eden will fail unless we collect.
 422 
 423   // First level allocation failure, scavenge and allocate in young gen.
 424   GCCauseSetter gccs(this, GCCause::_allocation_failure);
 425   const bool invoked_full_gc = PSScavenge::invoke();
 426   HeapWord* result = young_gen()->allocate(size);
 427 
 428   // Second level allocation failure.
 429   //   Mark sweep and allocate in young generation.
 430   if (result == NULL && !invoked_full_gc) {
 431     do_full_collection(false);
 432     result = young_gen()->allocate(size);
 433   }
 434 
 435   death_march_check(result, size);
 436 
 437   // Third level allocation failure.
 438   //   After mark sweep and young generation allocation failure,
 439   //   allocate in old generation.
 440   if (result == NULL) {
 441     result = old_gen()->allocate(size);
 442   }
 443 
 444   // Fourth level allocation failure. We're running out of memory.
 445   //   More complete mark sweep and allocate in young generation.
 446   if (result == NULL) {
 447     do_full_collection(true);
 448     result = young_gen()->allocate(size);
 449   }
 450 
 451   // Fifth level allocation failure.
 452   //   After more complete mark sweep, allocate in old generation.
 453   if (result == NULL) {
 454     result = old_gen()->allocate(size);
 455   }
 456 
 457   return result;
 458 }
 459 
 460 void ParallelScavengeHeap::ensure_parsability(bool retire_tlabs) {
 461   CollectedHeap::ensure_parsability(retire_tlabs);
 462   young_gen()->eden_space()->ensure_parsability();
 463 }
 464 
 465 size_t ParallelScavengeHeap::tlab_capacity(Thread* thr) const {
 466   return young_gen()->eden_space()->tlab_capacity(thr);
 467 }
 468 
 469 size_t ParallelScavengeHeap::tlab_used(Thread* thr) const {
 470   return young_gen()->eden_space()->tlab_used(thr);
 471 }
 472 
 473 size_t ParallelScavengeHeap::unsafe_max_tlab_alloc(Thread* thr) const {
 474   return young_gen()->eden_space()->unsafe_max_tlab_alloc(thr);
 475 }
 476 
 477 HeapWord* ParallelScavengeHeap::allocate_new_tlab(size_t size) {
 478   return young_gen()->allocate(size);
 479 }
 480 
 481 void ParallelScavengeHeap::accumulate_statistics_all_tlabs() {
 482   CollectedHeap::accumulate_statistics_all_tlabs();
 483 }
 484 
 485 void ParallelScavengeHeap::resize_all_tlabs() {
 486   CollectedHeap::resize_all_tlabs();
 487 }
 488 
 489 bool ParallelScavengeHeap::can_elide_initializing_store_barrier(oop new_obj) {
 490   // We don't need barriers for stores to objects in the
 491   // young gen and, a fortiori, for initializing stores to
 492   // objects therein.
 493   return is_in_young(new_obj);
 494 }
 495 
 496 // This method is used by System.gc() and JVMTI.
 497 void ParallelScavengeHeap::collect(GCCause::Cause cause) {
 498   assert(!Heap_lock->owned_by_self(),
 499     "this thread should not own the Heap_lock");
 500 
 501   uint gc_count      = 0;
 502   uint full_gc_count = 0;
 503   {
 504     MutexLocker ml(Heap_lock);
 505     // This value is guarded by the Heap_lock
 506     gc_count      = total_collections();
 507     full_gc_count = total_full_collections();
 508   }
 509 
 510   VM_ParallelGCSystemGC op(gc_count, full_gc_count, cause);
 511   VMThread::execute(&op);
 512 }
 513 
 514 void ParallelScavengeHeap::object_iterate(ObjectClosure* cl) {
 515   young_gen()->object_iterate(cl);
 516   old_gen()->object_iterate(cl);
 517 }
 518 
 519 
 520 HeapWord* ParallelScavengeHeap::block_start(const void* addr) const {
 521   if (young_gen()->is_in_reserved(addr)) {
 522     assert(young_gen()->is_in(addr),
 523            "addr should be in allocated part of young gen");
 524     // called from os::print_location by find or VMError
 525     if (Debugging || VMError::fatal_error_in_progress())  return NULL;
 526     Unimplemented();
 527   } else if (old_gen()->is_in_reserved(addr)) {
 528     assert(old_gen()->is_in(addr),
 529            "addr should be in allocated part of old gen");
 530     return old_gen()->start_array()->object_start((HeapWord*)addr);
 531   }
 532   return 0;
 533 }
 534 
 535 size_t ParallelScavengeHeap::block_size(const HeapWord* addr) const {
 536   return oop(addr)->size();
 537 }
 538 
 539 bool ParallelScavengeHeap::block_is_obj(const HeapWord* addr) const {
 540   return block_start(addr) == addr;
 541 }
 542 
 543 jlong ParallelScavengeHeap::millis_since_last_gc() {
 544   return UseParallelOldGC ?
 545     PSParallelCompact::millis_since_last_gc() :
 546     PSMarkSweep::millis_since_last_gc();
 547 }
 548 
 549 void ParallelScavengeHeap::prepare_for_verify() {
 550   ensure_parsability(false);  // no need to retire TLABs for verification
 551 }
 552 
 553 PSHeapSummary ParallelScavengeHeap::create_ps_heap_summary() {
 554   PSOldGen* old = old_gen();
 555   HeapWord* old_committed_end = (HeapWord*)old->virtual_space()->committed_high_addr();
 556   VirtualSpaceSummary old_summary(old->reserved().start(), old_committed_end, old->reserved().end());
 557   SpaceSummary old_space(old->reserved().start(), old_committed_end, old->used_in_bytes());
 558 
 559   PSYoungGen* young = young_gen();
 560   VirtualSpaceSummary young_summary(young->reserved().start(),
 561     (HeapWord*)young->virtual_space()->committed_high_addr(), young->reserved().end());
 562 
 563   MutableSpace* eden = young_gen()->eden_space();
 564   SpaceSummary eden_space(eden->bottom(), eden->end(), eden->used_in_bytes());
 565 
 566   MutableSpace* from = young_gen()->from_space();
 567   SpaceSummary from_space(from->bottom(), from->end(), from->used_in_bytes());
 568 
 569   MutableSpace* to = young_gen()->to_space();
 570   SpaceSummary to_space(to->bottom(), to->end(), to->used_in_bytes());
 571 
 572   VirtualSpaceSummary heap_summary = create_heap_space_summary();
 573   return PSHeapSummary(heap_summary, used(), old_summary, old_space, young_summary, eden_space, from_space, to_space);
 574 }
 575 
 576 void ParallelScavengeHeap::print_on(outputStream* st) const {
 577   young_gen()->print_on(st);
 578   old_gen()->print_on(st);
 579   MetaspaceAux::print_on(st);
 580 }
 581 
 582 void ParallelScavengeHeap::print_on_error(outputStream* st) const {
 583   this->CollectedHeap::print_on_error(st);
 584 
 585   if (UseParallelOldGC) {
 586     st->cr();
 587     PSParallelCompact::print_on_error(st);
 588   }
 589 }
 590 
 591 void ParallelScavengeHeap::gc_threads_do(ThreadClosure* tc) const {
 592   PSScavenge::gc_task_manager()->threads_do(tc);
 593 }
 594 
 595 void ParallelScavengeHeap::print_gc_threads_on(outputStream* st) const {
 596   PSScavenge::gc_task_manager()->print_threads_on(st);
 597 }
 598 
 599 void ParallelScavengeHeap::print_tracing_info() const {
 600   AdaptiveSizePolicyOutput::print();
 601   log_debug(gc, heap, exit)("Accumulated young generation GC time %3.7f secs", PSScavenge::accumulated_time()->seconds());
 602   log_debug(gc, heap, exit)("Accumulated old generation GC time %3.7f secs",
 603       UseParallelOldGC ? PSParallelCompact::accumulated_time()->seconds() : PSMarkSweep::accumulated_time()->seconds());
 604 }
 605 
 606 
 607 void ParallelScavengeHeap::verify(VerifyOption option /* ignored */) {
 608   // Why do we need the total_collections()-filter below?
 609   if (total_collections() > 0) {
 610     log_debug(gc, verify)("Tenured");
 611     old_gen()->verify();
 612 
 613     log_debug(gc, verify)("Eden");
 614     young_gen()->verify();
 615   }
 616 }
 617 
 618 void ParallelScavengeHeap::trace_heap(GCWhen::Type when, const GCTracer* gc_tracer) {
 619   const PSHeapSummary& heap_summary = create_ps_heap_summary();
 620   gc_tracer->report_gc_heap_summary(when, heap_summary);
 621 
 622   const MetaspaceSummary& metaspace_summary = create_metaspace_summary();
 623   gc_tracer->report_metaspace_summary(when, metaspace_summary);
 624 }
 625 
 626 ParallelScavengeHeap* ParallelScavengeHeap::heap() {
 627   CollectedHeap* heap = Universe::heap();
 628   assert(heap != NULL, "Uninitialized access to ParallelScavengeHeap::heap()");
 629   assert(heap->kind() == CollectedHeap::ParallelScavengeHeap, "Not a ParallelScavengeHeap");
 630   return (ParallelScavengeHeap*)heap;
 631 }
 632 
 633 // Before delegating the resize to the young generation,
 634 // the reserved space for the young and old generations
 635 // may be changed to accommodate the desired resize.
 636 void ParallelScavengeHeap::resize_young_gen(size_t eden_size,
 637     size_t survivor_size) {
 638   if (UseAdaptiveGCBoundary) {
 639     if (size_policy()->bytes_absorbed_from_eden() != 0) {
 640       size_policy()->reset_bytes_absorbed_from_eden();
 641       return;  // The generation changed size already.
 642     }
 643     gens()->adjust_boundary_for_young_gen_needs(eden_size, survivor_size);
 644   }
 645 
 646   // Delegate the resize to the generation.
 647   _young_gen->resize(eden_size, survivor_size);
 648 }
 649 
 650 // Before delegating the resize to the old generation,
 651 // the reserved space for the young and old generations
 652 // may be changed to accommodate the desired resize.
 653 void ParallelScavengeHeap::resize_old_gen(size_t desired_free_space) {
 654   if (UseAdaptiveGCBoundary) {
 655     if (size_policy()->bytes_absorbed_from_eden() != 0) {
 656       size_policy()->reset_bytes_absorbed_from_eden();
 657       return;  // The generation changed size already.
 658     }
 659     gens()->adjust_boundary_for_old_gen_needs(desired_free_space);
 660   }
 661 
 662   // Delegate the resize to the generation.
 663   _old_gen->resize(desired_free_space);
 664 }
 665 
 666 ParallelScavengeHeap::ParStrongRootsScope::ParStrongRootsScope() {
 667   // nothing particular
 668 }
 669 
 670 ParallelScavengeHeap::ParStrongRootsScope::~ParStrongRootsScope() {
 671   // nothing particular
 672 }
 673 
 674 #ifndef PRODUCT
 675 void ParallelScavengeHeap::record_gen_tops_before_GC() {
 676   if (ZapUnusedHeapArea) {
 677     young_gen()->record_spaces_top();
 678     old_gen()->record_spaces_top();
 679   }
 680 }
 681 
 682 void ParallelScavengeHeap::gen_mangle_unused_area() {
 683   if (ZapUnusedHeapArea) {
 684     young_gen()->eden_space()->mangle_unused_area();
 685     young_gen()->to_space()->mangle_unused_area();
 686     young_gen()->from_space()->mangle_unused_area();
 687     old_gen()->object_space()->mangle_unused_area();
 688   }
 689 }
 690 #endif
 691 
 692 bool ParallelScavengeHeap::is_scavengable(oop obj) {
 693   return is_in_young(obj);
 694 }
 695 
 696 void ParallelScavengeHeap::register_nmethod(nmethod* nm) {
 697   CodeCache::register_scavenge_root_nmethod(nm);
 698 }
 699 
 700 void ParallelScavengeHeap::verify_nmethod(nmethod* nm) {
 701   CodeCache::verify_scavenge_root_nmethod(nm);
 702 }
 703 
 704 GrowableArray<GCMemoryManager*> ParallelScavengeHeap::memory_managers() {
 705   GrowableArray<GCMemoryManager*> memory_managers(2);
 706   memory_managers.append(_young_manager);
 707   memory_managers.append(_old_manager);
 708   return memory_managers;
 709 }
 710 
 711 GrowableArray<MemoryPool*> ParallelScavengeHeap::memory_pools() {
 712   GrowableArray<MemoryPool*> memory_pools(3);
 713   memory_pools.append(_eden_pool);
 714   memory_pools.append(_survivor_pool);
 715   memory_pools.append(_old_pool);
 716   return memory_pools;
 717 }
 718 
--- EOF ---