| /* |
| * Copyright (c) 2000, 2012, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| * |
| */ |
| |
| #include "precompiled.hpp" |
| #include "classfile/symbolTable.hpp" |
| #include "classfile/systemDictionary.hpp" |
| #include "classfile/vmSymbols.hpp" |
| #include "code/icBuffer.hpp" |
| #include "gc_implementation/shared/collectorCounters.hpp" |
| #include "gc_implementation/shared/vmGCOperations.hpp" |
| #include "gc_interface/collectedHeap.inline.hpp" |
| #include "memory/compactPermGen.hpp" |
| #include "memory/filemap.hpp" |
| #include "memory/gcLocker.inline.hpp" |
| #include "memory/genCollectedHeap.hpp" |
| #include "memory/genOopClosures.inline.hpp" |
| #include "memory/generation.inline.hpp" |
| #include "memory/generationSpec.hpp" |
| #include "memory/permGen.hpp" |
| #include "memory/resourceArea.hpp" |
| #include "memory/sharedHeap.hpp" |
| #include "memory/space.hpp" |
| #include "oops/oop.inline.hpp" |
| #include "oops/oop.inline2.hpp" |
| #include "runtime/aprofiler.hpp" |
| #include "runtime/biasedLocking.hpp" |
| #include "runtime/fprofiler.hpp" |
| #include "runtime/handles.hpp" |
| #include "runtime/handles.inline.hpp" |
| #include "runtime/java.hpp" |
| #include "runtime/vmThread.hpp" |
| #include "services/memoryService.hpp" |
| #include "utilities/vmError.hpp" |
| #include "utilities/workgroup.hpp" |
| #ifndef SERIALGC |
| #include "gc_implementation/concurrentMarkSweep/concurrentMarkSweepThread.hpp" |
| #include "gc_implementation/concurrentMarkSweep/vmCMSOperations.hpp" |
| #endif |
| |
| GenCollectedHeap* GenCollectedHeap::_gch; |
| NOT_PRODUCT(size_t GenCollectedHeap::_skip_header_HeapWords = 0;) |
| |
| // The set of potentially parallel tasks in strong root scanning. |
| enum GCH_process_strong_roots_tasks { |
| // We probably want to parallelize both of these internally, but for now... |
| GCH_PS_younger_gens, |
| // Leave this one last. |
| GCH_PS_NumElements |
| }; |
| |
| GenCollectedHeap::GenCollectedHeap(GenCollectorPolicy *policy) : |
| SharedHeap(policy), |
| _gen_policy(policy), |
| _gen_process_strong_tasks(new SubTasksDone(GCH_PS_NumElements)), |
| _full_collections_completed(0) |
| { |
| if (_gen_process_strong_tasks == NULL || |
| !_gen_process_strong_tasks->valid()) { |
| vm_exit_during_initialization("Failed necessary allocation."); |
| } |
| assert(policy != NULL, "Sanity check"); |
| _preloading_shared_classes = false; |
| } |
| |
| jint GenCollectedHeap::initialize() { |
| CollectedHeap::pre_initialize(); |
| |
| int i; |
| _n_gens = gen_policy()->number_of_generations(); |
| |
| // While there are no constraints in the GC code that HeapWordSize |
| // be any particular value, there are multiple other areas in the |
| // system which believe this to be true (e.g. oop->object_size in some |
| // cases incorrectly returns the size in wordSize units rather than |
| // HeapWordSize). |
| guarantee(HeapWordSize == wordSize, "HeapWordSize must equal wordSize"); |
| |
| // The heap must be at least as aligned as generations. |
| size_t alignment = Generation::GenGrain; |
| |
| _gen_specs = gen_policy()->generations(); |
| PermanentGenerationSpec *perm_gen_spec = |
| collector_policy()->permanent_generation(); |
| |
| // Make sure the sizes are all aligned. |
| for (i = 0; i < _n_gens; i++) { |
| _gen_specs[i]->align(alignment); |
| } |
| perm_gen_spec->align(alignment); |
| |
| // If we are dumping the heap, then allocate a wasted block of address |
| // space in order to push the heap to a lower address. This extra |
| // address range allows for other (or larger) libraries to be loaded |
| // without them occupying the space required for the shared spaces. |
| |
| if (DumpSharedSpaces) { |
| uintx reserved = 0; |
| uintx block_size = 64*1024*1024; |
| while (reserved < SharedDummyBlockSize) { |
| char* dummy = os::reserve_memory(block_size); |
| reserved += block_size; |
| } |
| } |
| |
| // Allocate space for the heap. |
| |
| char* heap_address; |
| size_t total_reserved = 0; |
| int n_covered_regions = 0; |
| ReservedSpace heap_rs(0); |
| |
| heap_address = allocate(alignment, perm_gen_spec, &total_reserved, |
| &n_covered_regions, &heap_rs); |
| |
| if (UseSharedSpaces) { |
| if (!heap_rs.is_reserved() || heap_address != heap_rs.base()) { |
| if (heap_rs.is_reserved()) { |
| heap_rs.release(); |
| } |
| FileMapInfo* mapinfo = FileMapInfo::current_info(); |
| mapinfo->fail_continue("Unable to reserve shared region."); |
| allocate(alignment, perm_gen_spec, &total_reserved, &n_covered_regions, |
| &heap_rs); |
| } |
| } |
| |
| if (!heap_rs.is_reserved()) { |
| vm_shutdown_during_initialization( |
| "Could not reserve enough space for object heap"); |
| return JNI_ENOMEM; |
| } |
| |
| _reserved = MemRegion((HeapWord*)heap_rs.base(), |
| (HeapWord*)(heap_rs.base() + heap_rs.size())); |
| |
| // It is important to do this in a way such that concurrent readers can't |
| // temporarily think somethings in the heap. (Seen this happen in asserts.) |
| _reserved.set_word_size(0); |
| _reserved.set_start((HeapWord*)heap_rs.base()); |
| size_t actual_heap_size = heap_rs.size() - perm_gen_spec->misc_data_size() |
| - perm_gen_spec->misc_code_size(); |
| _reserved.set_end((HeapWord*)(heap_rs.base() + actual_heap_size)); |
| |
| _rem_set = collector_policy()->create_rem_set(_reserved, n_covered_regions); |
| set_barrier_set(rem_set()->bs()); |
| |
| _gch = this; |
| |
| for (i = 0; i < _n_gens; i++) { |
| ReservedSpace this_rs = heap_rs.first_part(_gen_specs[i]->max_size(), |
| UseSharedSpaces, UseSharedSpaces); |
| _gens[i] = _gen_specs[i]->init(this_rs, i, rem_set()); |
| heap_rs = heap_rs.last_part(_gen_specs[i]->max_size()); |
| } |
| _perm_gen = perm_gen_spec->init(heap_rs, PermSize, rem_set()); |
| |
| clear_incremental_collection_failed(); |
| |
| #ifndef SERIALGC |
| // If we are running CMS, create the collector responsible |
| // for collecting the CMS generations. |
| if (collector_policy()->is_concurrent_mark_sweep_policy()) { |
| bool success = create_cms_collector(); |
| if (!success) return JNI_ENOMEM; |
| } |
| #endif // SERIALGC |
| |
| return JNI_OK; |
| } |
| |
| |
| char* GenCollectedHeap::allocate(size_t alignment, |
| PermanentGenerationSpec* perm_gen_spec, |
| size_t* _total_reserved, |
| int* _n_covered_regions, |
| ReservedSpace* heap_rs){ |
| const char overflow_msg[] = "The size of the object heap + VM data exceeds " |
| "the maximum representable size"; |
| |
| // Now figure out the total size. |
| size_t total_reserved = 0; |
| int n_covered_regions = 0; |
| const size_t pageSize = UseLargePages ? |
| os::large_page_size() : os::vm_page_size(); |
| |
| for (int i = 0; i < _n_gens; i++) { |
| total_reserved += _gen_specs[i]->max_size(); |
| if (total_reserved < _gen_specs[i]->max_size()) { |
| vm_exit_during_initialization(overflow_msg); |
| } |
| n_covered_regions += _gen_specs[i]->n_covered_regions(); |
| } |
| assert(total_reserved % pageSize == 0, |
| err_msg("Gen size; total_reserved=" SIZE_FORMAT ", pageSize=" |
| SIZE_FORMAT, total_reserved, pageSize)); |
| total_reserved += perm_gen_spec->max_size(); |
| assert(total_reserved % pageSize == 0, |
| err_msg("Perm size; total_reserved=" SIZE_FORMAT ", pageSize=" |
| SIZE_FORMAT ", perm gen max=" SIZE_FORMAT, total_reserved, |
| pageSize, perm_gen_spec->max_size())); |
| |
| if (total_reserved < perm_gen_spec->max_size()) { |
| vm_exit_during_initialization(overflow_msg); |
| } |
| n_covered_regions += perm_gen_spec->n_covered_regions(); |
| |
| // Add the size of the data area which shares the same reserved area |
| // as the heap, but which is not actually part of the heap. |
| size_t s = perm_gen_spec->misc_data_size() + perm_gen_spec->misc_code_size(); |
| |
| total_reserved += s; |
| if (total_reserved < s) { |
| vm_exit_during_initialization(overflow_msg); |
| } |
| |
| if (UseLargePages) { |
| assert(total_reserved != 0, "total_reserved cannot be 0"); |
| total_reserved = round_to(total_reserved, os::large_page_size()); |
| if (total_reserved < os::large_page_size()) { |
| vm_exit_during_initialization(overflow_msg); |
| } |
| } |
| |
| // Calculate the address at which the heap must reside in order for |
| // the shared data to be at the required address. |
| |
| char* heap_address; |
| if (UseSharedSpaces) { |
| |
| // Calculate the address of the first word beyond the heap. |
| FileMapInfo* mapinfo = FileMapInfo::current_info(); |
| int lr = CompactingPermGenGen::n_regions - 1; |
| size_t capacity = align_size_up(mapinfo->space_capacity(lr), alignment); |
| heap_address = mapinfo->region_base(lr) + capacity; |
| |
| // Calculate the address of the first word of the heap. |
| heap_address -= total_reserved; |
| } else { |
| heap_address = NULL; // any address will do. |
| if (UseCompressedOops) { |
| heap_address = Universe::preferred_heap_base(total_reserved, Universe::UnscaledNarrowOop); |
| *_total_reserved = total_reserved; |
| *_n_covered_regions = n_covered_regions; |
| *heap_rs = ReservedHeapSpace(total_reserved, alignment, |
| UseLargePages, heap_address); |
| |
| if (heap_address != NULL && !heap_rs->is_reserved()) { |
| // Failed to reserve at specified address - the requested memory |
| // region is taken already, for example, by 'java' launcher. |
| // Try again to reserver heap higher. |
| heap_address = Universe::preferred_heap_base(total_reserved, Universe::ZeroBasedNarrowOop); |
| *heap_rs = ReservedHeapSpace(total_reserved, alignment, |
| UseLargePages, heap_address); |
| |
| if (heap_address != NULL && !heap_rs->is_reserved()) { |
| // Failed to reserve at specified address again - give up. |
| heap_address = Universe::preferred_heap_base(total_reserved, Universe::HeapBasedNarrowOop); |
| assert(heap_address == NULL, ""); |
| *heap_rs = ReservedHeapSpace(total_reserved, alignment, |
| UseLargePages, heap_address); |
| } |
| } |
| return heap_address; |
| } |
| } |
| |
| *_total_reserved = total_reserved; |
| *_n_covered_regions = n_covered_regions; |
| *heap_rs = ReservedHeapSpace(total_reserved, alignment, |
| UseLargePages, heap_address); |
| |
| return heap_address; |
| } |
| |
| |
| void GenCollectedHeap::post_initialize() { |
| SharedHeap::post_initialize(); |
| TwoGenerationCollectorPolicy *policy = |
| (TwoGenerationCollectorPolicy *)collector_policy(); |
| guarantee(policy->is_two_generation_policy(), "Illegal policy type"); |
| DefNewGeneration* def_new_gen = (DefNewGeneration*) get_gen(0); |
| assert(def_new_gen->kind() == Generation::DefNew || |
| def_new_gen->kind() == Generation::ParNew || |
| def_new_gen->kind() == Generation::ASParNew, |
| "Wrong generation kind"); |
| |
| Generation* old_gen = get_gen(1); |
| assert(old_gen->kind() == Generation::ConcurrentMarkSweep || |
| old_gen->kind() == Generation::ASConcurrentMarkSweep || |
| old_gen->kind() == Generation::MarkSweepCompact, |
| "Wrong generation kind"); |
| |
| policy->initialize_size_policy(def_new_gen->eden()->capacity(), |
| old_gen->capacity(), |
| def_new_gen->from()->capacity()); |
| policy->initialize_gc_policy_counters(); |
| } |
| |
| void GenCollectedHeap::ref_processing_init() { |
| SharedHeap::ref_processing_init(); |
| for (int i = 0; i < _n_gens; i++) { |
| _gens[i]->ref_processor_init(); |
| } |
| } |
| |
| size_t GenCollectedHeap::capacity() const { |
| size_t res = 0; |
| for (int i = 0; i < _n_gens; i++) { |
| res += _gens[i]->capacity(); |
| } |
| return res; |
| } |
| |
| size_t GenCollectedHeap::used() const { |
| size_t res = 0; |
| for (int i = 0; i < _n_gens; i++) { |
| res += _gens[i]->used(); |
| } |
| return res; |
| } |
| |
| // Save the "used_region" for generations level and lower, |
| // and, if perm is true, for perm gen. |
| void GenCollectedHeap::save_used_regions(int level, bool perm) { |
| assert(level < _n_gens, "Illegal level parameter"); |
| for (int i = level; i >= 0; i--) { |
| _gens[i]->save_used_region(); |
| } |
| if (perm) { |
| perm_gen()->save_used_region(); |
| } |
| } |
| |
| size_t GenCollectedHeap::max_capacity() const { |
| size_t res = 0; |
| for (int i = 0; i < _n_gens; i++) { |
| res += _gens[i]->max_capacity(); |
| } |
| return res; |
| } |
| |
| // Update the _full_collections_completed counter |
| // at the end of a stop-world full GC. |
| unsigned int GenCollectedHeap::update_full_collections_completed() { |
| MonitorLockerEx ml(FullGCCount_lock, Mutex::_no_safepoint_check_flag); |
| assert(_full_collections_completed <= _total_full_collections, |
| "Can't complete more collections than were started"); |
| _full_collections_completed = _total_full_collections; |
| ml.notify_all(); |
| return _full_collections_completed; |
| } |
| |
| // Update the _full_collections_completed counter, as appropriate, |
| // at the end of a concurrent GC cycle. Note the conditional update |
| // below to allow this method to be called by a concurrent collector |
| // without synchronizing in any manner with the VM thread (which |
| // may already have initiated a STW full collection "concurrently"). |
| unsigned int GenCollectedHeap::update_full_collections_completed(unsigned int count) { |
| MonitorLockerEx ml(FullGCCount_lock, Mutex::_no_safepoint_check_flag); |
| assert((_full_collections_completed <= _total_full_collections) && |
| (count <= _total_full_collections), |
| "Can't complete more collections than were started"); |
| if (count > _full_collections_completed) { |
| _full_collections_completed = count; |
| ml.notify_all(); |
| } |
| return _full_collections_completed; |
| } |
| |
| |
| #ifndef PRODUCT |
| // Override of memory state checking method in CollectedHeap: |
| // Some collectors (CMS for example) can't have badHeapWordVal written |
| // in the first two words of an object. (For instance , in the case of |
| // CMS these words hold state used to synchronize between certain |
| // (concurrent) GC steps and direct allocating mutators.) |
| // The skip_header_HeapWords() method below, allows us to skip |
| // over the requisite number of HeapWord's. Note that (for |
| // generational collectors) this means that those many words are |
| // skipped in each object, irrespective of the generation in which |
| // that object lives. The resultant loss of precision seems to be |
| // harmless and the pain of avoiding that imprecision appears somewhat |
| // higher than we are prepared to pay for such rudimentary debugging |
| // support. |
| void GenCollectedHeap::check_for_non_bad_heap_word_value(HeapWord* addr, |
| size_t size) { |
| if (CheckMemoryInitialization && ZapUnusedHeapArea) { |
| // We are asked to check a size in HeapWords, |
| // but the memory is mangled in juint words. |
| juint* start = (juint*) (addr + skip_header_HeapWords()); |
| juint* end = (juint*) (addr + size); |
| for (juint* slot = start; slot < end; slot += 1) { |
| assert(*slot == badHeapWordVal, |
| "Found non badHeapWordValue in pre-allocation check"); |
| } |
| } |
| } |
| #endif |
| |
| HeapWord* GenCollectedHeap::attempt_allocation(size_t size, |
| bool is_tlab, |
| bool first_only) { |
| HeapWord* res; |
| for (int i = 0; i < _n_gens; i++) { |
| if (_gens[i]->should_allocate(size, is_tlab)) { |
| res = _gens[i]->allocate(size, is_tlab); |
| if (res != NULL) return res; |
| else if (first_only) break; |
| } |
| } |
| // Otherwise... |
| return NULL; |
| } |
| |
| HeapWord* GenCollectedHeap::mem_allocate(size_t size, |
| bool* gc_overhead_limit_was_exceeded) { |
| return collector_policy()->mem_allocate_work(size, |
| false /* is_tlab */, |
| gc_overhead_limit_was_exceeded); |
| } |
| |
| bool GenCollectedHeap::must_clear_all_soft_refs() { |
| return _gc_cause == GCCause::_last_ditch_collection; |
| } |
| |
| bool GenCollectedHeap::should_do_concurrent_full_gc(GCCause::Cause cause) { |
| return UseConcMarkSweepGC && |
| ((cause == GCCause::_gc_locker && GCLockerInvokesConcurrent) || |
| (cause == GCCause::_java_lang_system_gc && ExplicitGCInvokesConcurrent)); |
| } |
| |
| void GenCollectedHeap::do_collection(bool full, |
| bool clear_all_soft_refs, |
| size_t size, |
| bool is_tlab, |
| int max_level) { |
| bool prepared_for_verification = false; |
| ResourceMark rm; |
| DEBUG_ONLY(Thread* my_thread = Thread::current();) |
| |
| assert(SafepointSynchronize::is_at_safepoint(), "should be at safepoint"); |
| assert(my_thread->is_VM_thread() || |
| my_thread->is_ConcurrentGC_thread(), |
| "incorrect thread type capability"); |
| assert(Heap_lock->is_locked(), |
| "the requesting thread should have the Heap_lock"); |
| guarantee(!is_gc_active(), "collection is not reentrant"); |
| assert(max_level < n_gens(), "sanity check"); |
| |
| if (GC_locker::check_active_before_gc()) { |
| return; // GC is disabled (e.g. JNI GetXXXCritical operation) |
| } |
| |
| const bool do_clear_all_soft_refs = clear_all_soft_refs || |
| collector_policy()->should_clear_all_soft_refs(); |
| |
| ClearedAllSoftRefs casr(do_clear_all_soft_refs, collector_policy()); |
| |
| const size_t perm_prev_used = perm_gen()->used(); |
| |
| print_heap_before_gc(); |
| if (Verbose) { |
| gclog_or_tty->print_cr("GC Cause: %s", GCCause::to_string(gc_cause())); |
| } |
| |
| { |
| FlagSetting fl(_is_gc_active, true); |
| |
| bool complete = full && (max_level == (n_gens()-1)); |
| const char* gc_cause_str = "GC "; |
| if (complete) { |
| GCCause::Cause cause = gc_cause(); |
| if (cause == GCCause::_java_lang_system_gc) { |
| gc_cause_str = "Full GC (System) "; |
| } else { |
| gc_cause_str = "Full GC "; |
| } |
| } |
| gclog_or_tty->date_stamp(PrintGC && PrintGCDateStamps); |
| TraceCPUTime tcpu(PrintGCDetails, true, gclog_or_tty); |
| TraceTime t(gc_cause_str, PrintGCDetails, false, gclog_or_tty); |
| |
| gc_prologue(complete); |
| increment_total_collections(complete); |
| |
| size_t gch_prev_used = used(); |
| |
| int starting_level = 0; |
| if (full) { |
| // Search for the oldest generation which will collect all younger |
| // generations, and start collection loop there. |
| for (int i = max_level; i >= 0; i--) { |
| if (_gens[i]->full_collects_younger_generations()) { |
| starting_level = i; |
| break; |
| } |
| } |
| } |
| |
| bool must_restore_marks_for_biased_locking = false; |
| |
| int max_level_collected = starting_level; |
| for (int i = starting_level; i <= max_level; i++) { |
| if (_gens[i]->should_collect(full, size, is_tlab)) { |
| if (i == n_gens() - 1) { // a major collection is to happen |
| if (!complete) { |
| // The full_collections increment was missed above. |
| increment_total_full_collections(); |
| } |
| pre_full_gc_dump(); // do any pre full gc dumps |
| } |
| // Timer for individual generations. Last argument is false: no CR |
| TraceTime t1(_gens[i]->short_name(), PrintGCDetails, false, gclog_or_tty); |
| TraceCollectorStats tcs(_gens[i]->counters()); |
| TraceMemoryManagerStats tmms(_gens[i]->kind(),gc_cause()); |
| |
| size_t prev_used = _gens[i]->used(); |
| _gens[i]->stat_record()->invocations++; |
| _gens[i]->stat_record()->accumulated_time.start(); |
| |
| // Must be done anew before each collection because |
| // a previous collection will do mangling and will |
| // change top of some spaces. |
| record_gen_tops_before_GC(); |
| |
| if (PrintGC && Verbose) { |
| gclog_or_tty->print("level=%d invoke=%d size=" SIZE_FORMAT, |
| i, |
| _gens[i]->stat_record()->invocations, |
| size*HeapWordSize); |
| } |
| |
| if (VerifyBeforeGC && i >= VerifyGCLevel && |
| total_collections() >= VerifyGCStartAt) { |
| HandleMark hm; // Discard invalid handles created during verification |
| if (!prepared_for_verification) { |
| prepare_for_verify(); |
| prepared_for_verification = true; |
| } |
| gclog_or_tty->print(" VerifyBeforeGC:"); |
| Universe::verify(true); |
| } |
| COMPILER2_PRESENT(DerivedPointerTable::clear()); |
| |
| if (!must_restore_marks_for_biased_locking && |
| _gens[i]->performs_in_place_marking()) { |
| // We perform this mark word preservation work lazily |
| // because it's only at this point that we know whether we |
| // absolutely have to do it; we want to avoid doing it for |
| // scavenge-only collections where it's unnecessary |
| must_restore_marks_for_biased_locking = true; |
| BiasedLocking::preserve_marks(); |
| } |
| |
| // Do collection work |
| { |
| // Note on ref discovery: For what appear to be historical reasons, |
| // GCH enables and disabled (by enqueing) refs discovery. |
| // In the future this should be moved into the generation's |
| // collect method so that ref discovery and enqueueing concerns |
| // are local to a generation. The collect method could return |
| // an appropriate indication in the case that notification on |
| // the ref lock was needed. This will make the treatment of |
| // weak refs more uniform (and indeed remove such concerns |
| // from GCH). XXX |
| |
| HandleMark hm; // Discard invalid handles created during gc |
| save_marks(); // save marks for all gens |
| // We want to discover references, but not process them yet. |
| // This mode is disabled in process_discovered_references if the |
| // generation does some collection work, or in |
| // enqueue_discovered_references if the generation returns |
| // without doing any work. |
| ReferenceProcessor* rp = _gens[i]->ref_processor(); |
| // If the discovery of ("weak") refs in this generation is |
| // atomic wrt other collectors in this configuration, we |
| // are guaranteed to have empty discovered ref lists. |
| if (rp->discovery_is_atomic()) { |
| rp->enable_discovery(true /*verify_disabled*/, true /*verify_no_refs*/); |
| rp->setup_policy(do_clear_all_soft_refs); |
| } else { |
| // collect() below will enable discovery as appropriate |
| } |
| _gens[i]->collect(full, do_clear_all_soft_refs, size, is_tlab); |
| if (!rp->enqueuing_is_done()) { |
| rp->enqueue_discovered_references(); |
| } else { |
| rp->set_enqueuing_is_done(false); |
| } |
| rp->verify_no_references_recorded(); |
| } |
| max_level_collected = i; |
| |
| // Determine if allocation request was met. |
| if (size > 0) { |
| if (!is_tlab || _gens[i]->supports_tlab_allocation()) { |
| if (size*HeapWordSize <= _gens[i]->unsafe_max_alloc_nogc()) { |
| size = 0; |
| } |
| } |
| } |
| |
| COMPILER2_PRESENT(DerivedPointerTable::update_pointers()); |
| |
| _gens[i]->stat_record()->accumulated_time.stop(); |
| |
| update_gc_stats(i, full); |
| |
| if (VerifyAfterGC && i >= VerifyGCLevel && |
| total_collections() >= VerifyGCStartAt) { |
| HandleMark hm; // Discard invalid handles created during verification |
| gclog_or_tty->print(" VerifyAfterGC:"); |
| Universe::verify(false); |
| } |
| |
| if (PrintGCDetails) { |
| gclog_or_tty->print(":"); |
| _gens[i]->print_heap_change(prev_used); |
| } |
| } |
| } |
| |
| // Update "complete" boolean wrt what actually transpired -- |
| // for instance, a promotion failure could have led to |
| // a whole heap collection. |
| complete = complete || (max_level_collected == n_gens() - 1); |
| |
| if (complete) { // We did a "major" collection |
| post_full_gc_dump(); // do any post full gc dumps |
| } |
| |
| if (PrintGCDetails) { |
| print_heap_change(gch_prev_used); |
| |
| // Print perm gen info for full GC with PrintGCDetails flag. |
| if (complete) { |
| print_perm_heap_change(perm_prev_used); |
| } |
| } |
| |
| for (int j = max_level_collected; j >= 0; j -= 1) { |
| // Adjust generation sizes. |
| _gens[j]->compute_new_size(); |
| } |
| |
| if (complete) { |
| // Ask the permanent generation to adjust size for full collections |
| perm()->compute_new_size(); |
| update_full_collections_completed(); |
| } |
| |
| // Track memory usage and detect low memory after GC finishes |
| MemoryService::track_memory_usage(); |
| |
| gc_epilogue(complete); |
| |
| if (must_restore_marks_for_biased_locking) { |
| BiasedLocking::restore_marks(); |
| } |
| } |
| |
| AdaptiveSizePolicy* sp = gen_policy()->size_policy(); |
| AdaptiveSizePolicyOutput(sp, total_collections()); |
| |
| print_heap_after_gc(); |
| |
| #ifdef TRACESPINNING |
| ParallelTaskTerminator::print_termination_counts(); |
| #endif |
| |
| if (ExitAfterGCNum > 0 && total_collections() == ExitAfterGCNum) { |
| tty->print_cr("Stopping after GC #%d", ExitAfterGCNum); |
| vm_exit(-1); |
| } |
| } |
| |
| HeapWord* GenCollectedHeap::satisfy_failed_allocation(size_t size, bool is_tlab) { |
| return collector_policy()->satisfy_failed_allocation(size, is_tlab); |
| } |
| |
| void GenCollectedHeap::set_par_threads(uint t) { |
| SharedHeap::set_par_threads(t); |
| _gen_process_strong_tasks->set_n_threads(t); |
| } |
| |
| void GenCollectedHeap:: |
| gen_process_strong_roots(int level, |
| bool younger_gens_as_roots, |
| bool activate_scope, |
| bool collecting_perm_gen, |
| SharedHeap::ScanningOption so, |
| OopsInGenClosure* not_older_gens, |
| bool do_code_roots, |
| OopsInGenClosure* older_gens) { |
| // General strong roots. |
| |
| if (!do_code_roots) { |
| SharedHeap::process_strong_roots(activate_scope, collecting_perm_gen, so, |
| not_older_gens, NULL, older_gens); |
| } else { |
| bool do_code_marking = (activate_scope || nmethod::oops_do_marking_is_active()); |
| CodeBlobToOopClosure code_roots(not_older_gens, /*do_marking=*/ do_code_marking); |
| SharedHeap::process_strong_roots(activate_scope, collecting_perm_gen, so, |
| not_older_gens, &code_roots, older_gens); |
| } |
| |
| if (younger_gens_as_roots) { |
| if (!_gen_process_strong_tasks->is_task_claimed(GCH_PS_younger_gens)) { |
| for (int i = 0; i < level; i++) { |
| not_older_gens->set_generation(_gens[i]); |
| _gens[i]->oop_iterate(not_older_gens); |
| } |
| not_older_gens->reset_generation(); |
| } |
| } |
| // When collection is parallel, all threads get to cooperate to do |
| // older-gen scanning. |
| for (int i = level+1; i < _n_gens; i++) { |
| older_gens->set_generation(_gens[i]); |
| rem_set()->younger_refs_iterate(_gens[i], older_gens); |
| older_gens->reset_generation(); |
| } |
| |
| _gen_process_strong_tasks->all_tasks_completed(); |
| } |
| |
| void GenCollectedHeap::gen_process_weak_roots(OopClosure* root_closure, |
| CodeBlobClosure* code_roots, |
| OopClosure* non_root_closure) { |
| SharedHeap::process_weak_roots(root_closure, code_roots, non_root_closure); |
| // "Local" "weak" refs |
| for (int i = 0; i < _n_gens; i++) { |
| _gens[i]->ref_processor()->weak_oops_do(root_closure); |
| } |
| } |
| |
| #define GCH_SINCE_SAVE_MARKS_ITERATE_DEFN(OopClosureType, nv_suffix) \ |
| void GenCollectedHeap:: \ |
| oop_since_save_marks_iterate(int level, \ |
| OopClosureType* cur, \ |
| OopClosureType* older) { \ |
| _gens[level]->oop_since_save_marks_iterate##nv_suffix(cur); \ |
| for (int i = level+1; i < n_gens(); i++) { \ |
| _gens[i]->oop_since_save_marks_iterate##nv_suffix(older); \ |
| } \ |
| perm_gen()->oop_since_save_marks_iterate##nv_suffix(older); \ |
| } |
| |
| ALL_SINCE_SAVE_MARKS_CLOSURES(GCH_SINCE_SAVE_MARKS_ITERATE_DEFN) |
| |
| #undef GCH_SINCE_SAVE_MARKS_ITERATE_DEFN |
| |
| bool GenCollectedHeap::no_allocs_since_save_marks(int level) { |
| for (int i = level; i < _n_gens; i++) { |
| if (!_gens[i]->no_allocs_since_save_marks()) return false; |
| } |
| return perm_gen()->no_allocs_since_save_marks(); |
| } |
| |
| bool GenCollectedHeap::supports_inline_contig_alloc() const { |
| return _gens[0]->supports_inline_contig_alloc(); |
| } |
| |
| HeapWord** GenCollectedHeap::top_addr() const { |
| return _gens[0]->top_addr(); |
| } |
| |
| HeapWord** GenCollectedHeap::end_addr() const { |
| return _gens[0]->end_addr(); |
| } |
| |
| size_t GenCollectedHeap::unsafe_max_alloc() { |
| return _gens[0]->unsafe_max_alloc_nogc(); |
| } |
| |
| // public collection interfaces |
| |
| void GenCollectedHeap::collect(GCCause::Cause cause) { |
| if (should_do_concurrent_full_gc(cause)) { |
| #ifndef SERIALGC |
| // mostly concurrent full collection |
| collect_mostly_concurrent(cause); |
| #else // SERIALGC |
| ShouldNotReachHere(); |
| #endif // SERIALGC |
| } else { |
| #ifdef ASSERT |
| if (cause == GCCause::_scavenge_alot) { |
| // minor collection only |
| collect(cause, 0); |
| } else { |
| // Stop-the-world full collection |
| collect(cause, n_gens() - 1); |
| } |
| #else |
| // Stop-the-world full collection |
| collect(cause, n_gens() - 1); |
| #endif |
| } |
| } |
| |
| void GenCollectedHeap::collect(GCCause::Cause cause, int max_level) { |
| // The caller doesn't have the Heap_lock |
| assert(!Heap_lock->owned_by_self(), "this thread should not own the Heap_lock"); |
| MutexLocker ml(Heap_lock); |
| collect_locked(cause, max_level); |
| } |
| |
| // This interface assumes that it's being called by the |
| // vm thread. It collects the heap assuming that the |
| // heap lock is already held and that we are executing in |
| // the context of the vm thread. |
| void GenCollectedHeap::collect_as_vm_thread(GCCause::Cause cause) { |
| assert(Thread::current()->is_VM_thread(), "Precondition#1"); |
| assert(Heap_lock->is_locked(), "Precondition#2"); |
| GCCauseSetter gcs(this, cause); |
| switch (cause) { |
| case GCCause::_heap_inspection: |
| case GCCause::_heap_dump: { |
| HandleMark hm; |
| do_full_collection(false, // don't clear all soft refs |
| n_gens() - 1); |
| break; |
| } |
| default: // XXX FIX ME |
| ShouldNotReachHere(); // Unexpected use of this function |
| } |
| } |
| |
| void GenCollectedHeap::collect_locked(GCCause::Cause cause) { |
| // The caller has the Heap_lock |
| assert(Heap_lock->owned_by_self(), "this thread should own the Heap_lock"); |
| collect_locked(cause, n_gens() - 1); |
| } |
| |
| // this is the private collection interface |
| // The Heap_lock is expected to be held on entry. |
| |
| void GenCollectedHeap::collect_locked(GCCause::Cause cause, int max_level) { |
| if (_preloading_shared_classes) { |
| report_out_of_shared_space(SharedPermGen); |
| } |
| // Read the GC count while holding the Heap_lock |
| unsigned int gc_count_before = total_collections(); |
| unsigned int full_gc_count_before = total_full_collections(); |
| { |
| MutexUnlocker mu(Heap_lock); // give up heap lock, execute gets it back |
| VM_GenCollectFull op(gc_count_before, full_gc_count_before, |
| cause, max_level); |
| VMThread::execute(&op); |
| } |
| } |
| |
| #ifndef SERIALGC |
| bool GenCollectedHeap::create_cms_collector() { |
| |
| assert(((_gens[1]->kind() == Generation::ConcurrentMarkSweep) || |
| (_gens[1]->kind() == Generation::ASConcurrentMarkSweep)) && |
| _perm_gen->as_gen()->kind() == Generation::ConcurrentMarkSweep, |
| "Unexpected generation kinds"); |
| // Skip two header words in the block content verification |
| NOT_PRODUCT(_skip_header_HeapWords = CMSCollector::skip_header_HeapWords();) |
| CMSCollector* collector = new CMSCollector( |
| (ConcurrentMarkSweepGeneration*)_gens[1], |
| (ConcurrentMarkSweepGeneration*)_perm_gen->as_gen(), |
| _rem_set->as_CardTableRS(), |
| (ConcurrentMarkSweepPolicy*) collector_policy()); |
| |
| if (collector == NULL || !collector->completed_initialization()) { |
| if (collector) { |
| delete collector; // Be nice in embedded situation |
| } |
| vm_shutdown_during_initialization("Could not create CMS collector"); |
| return false; |
| } |
| return true; // success |
| } |
| |
| void GenCollectedHeap::collect_mostly_concurrent(GCCause::Cause cause) { |
| assert(!Heap_lock->owned_by_self(), "Should not own Heap_lock"); |
| |
| MutexLocker ml(Heap_lock); |
| // Read the GC counts while holding the Heap_lock |
| unsigned int full_gc_count_before = total_full_collections(); |
| unsigned int gc_count_before = total_collections(); |
| { |
| MutexUnlocker mu(Heap_lock); |
| VM_GenCollectFullConcurrent op(gc_count_before, full_gc_count_before, cause); |
| VMThread::execute(&op); |
| } |
| } |
| #endif // SERIALGC |
| |
| |
| void GenCollectedHeap::do_full_collection(bool clear_all_soft_refs, |
| int max_level) { |
| int local_max_level; |
| if (!incremental_collection_will_fail(false /* don't consult_young */) && |
| gc_cause() == GCCause::_gc_locker) { |
| local_max_level = 0; |
| } else { |
| local_max_level = max_level; |
| } |
| |
| do_collection(true /* full */, |
| clear_all_soft_refs /* clear_all_soft_refs */, |
| 0 /* size */, |
| false /* is_tlab */, |
| local_max_level /* max_level */); |
| // Hack XXX FIX ME !!! |
| // A scavenge may not have been attempted, or may have |
| // been attempted and failed, because the old gen was too full |
| if (local_max_level == 0 && gc_cause() == GCCause::_gc_locker && |
| incremental_collection_will_fail(false /* don't consult_young */)) { |
| if (PrintGCDetails) { |
| gclog_or_tty->print_cr("GC locker: Trying a full collection " |
| "because scavenge failed"); |
| } |
| // This time allow the old gen to be collected as well |
| do_collection(true /* full */, |
| clear_all_soft_refs /* clear_all_soft_refs */, |
| 0 /* size */, |
| false /* is_tlab */, |
| n_gens() - 1 /* max_level */); |
| } |
| } |
| |
| bool GenCollectedHeap::is_in_young(oop p) { |
| bool result = ((HeapWord*)p) < _gens[_n_gens - 1]->reserved().start(); |
| assert(result == _gens[0]->is_in_reserved(p), |
| err_msg("incorrect test - result=%d, p=" PTR_FORMAT, result, (void*)p)); |
| return result; |
| } |
| |
| // Returns "TRUE" iff "p" points into the committed areas of the heap. |
| bool GenCollectedHeap::is_in(const void* p) const { |
| #ifndef ASSERT |
| guarantee(VerifyBeforeGC || |
| VerifyDuringGC || |
| VerifyBeforeExit || |
| PrintAssembly || |
| tty->count() != 0 || // already printing |
| VerifyAfterGC || |
| VMError::fatal_error_in_progress(), "too expensive"); |
| |
| #endif |
| // This might be sped up with a cache of the last generation that |
| // answered yes. |
| for (int i = 0; i < _n_gens; i++) { |
| if (_gens[i]->is_in(p)) return true; |
| } |
| if (_perm_gen->as_gen()->is_in(p)) return true; |
| // Otherwise... |
| return false; |
| } |
| |
| #ifdef ASSERT |
| // Don't implement this by using is_in_young(). This method is used |
| // in some cases to check that is_in_young() is correct. |
| bool GenCollectedHeap::is_in_partial_collection(const void* p) { |
| assert(is_in_reserved(p) || p == NULL, |
| "Does not work if address is non-null and outside of the heap"); |
| // The order of the generations is young (low addr), old, perm (high addr) |
| return p < _gens[_n_gens - 2]->reserved().end() && p != NULL; |
| } |
| #endif |
| |
| void GenCollectedHeap::oop_iterate(OopClosure* cl) { |
| for (int i = 0; i < _n_gens; i++) { |
| _gens[i]->oop_iterate(cl); |
| } |
| } |
| |
| void GenCollectedHeap::oop_iterate(MemRegion mr, OopClosure* cl) { |
| for (int i = 0; i < _n_gens; i++) { |
| _gens[i]->oop_iterate(mr, cl); |
| } |
| } |
| |
| void GenCollectedHeap::object_iterate(ObjectClosure* cl) { |
| for (int i = 0; i < _n_gens; i++) { |
| _gens[i]->object_iterate(cl); |
| } |
| perm_gen()->object_iterate(cl); |
| } |
| |
| void GenCollectedHeap::safe_object_iterate(ObjectClosure* cl) { |
| for (int i = 0; i < _n_gens; i++) { |
| _gens[i]->safe_object_iterate(cl); |
| } |
| perm_gen()->safe_object_iterate(cl); |
| } |
| |
| void GenCollectedHeap::object_iterate_since_last_GC(ObjectClosure* cl) { |
| for (int i = 0; i < _n_gens; i++) { |
| _gens[i]->object_iterate_since_last_GC(cl); |
| } |
| } |
| |
| Space* GenCollectedHeap::space_containing(const void* addr) const { |
| for (int i = 0; i < _n_gens; i++) { |
| Space* res = _gens[i]->space_containing(addr); |
| if (res != NULL) return res; |
| } |
| Space* res = perm_gen()->space_containing(addr); |
| if (res != NULL) return res; |
| // Otherwise... |
| assert(false, "Could not find containing space"); |
| return NULL; |
| } |
| |
| |
| HeapWord* GenCollectedHeap::block_start(const void* addr) const { |
| assert(is_in_reserved(addr), "block_start of address outside of heap"); |
| for (int i = 0; i < _n_gens; i++) { |
| if (_gens[i]->is_in_reserved(addr)) { |
| assert(_gens[i]->is_in(addr), |
| "addr should be in allocated part of generation"); |
| return _gens[i]->block_start(addr); |
| } |
| } |
| if (perm_gen()->is_in_reserved(addr)) { |
| assert(perm_gen()->is_in(addr), |
| "addr should be in allocated part of perm gen"); |
| return perm_gen()->block_start(addr); |
| } |
| assert(false, "Some generation should contain the address"); |
| return NULL; |
| } |
| |
| size_t GenCollectedHeap::block_size(const HeapWord* addr) const { |
| assert(is_in_reserved(addr), "block_size of address outside of heap"); |
| for (int i = 0; i < _n_gens; i++) { |
| if (_gens[i]->is_in_reserved(addr)) { |
| assert(_gens[i]->is_in(addr), |
| "addr should be in allocated part of generation"); |
| return _gens[i]->block_size(addr); |
| } |
| } |
| if (perm_gen()->is_in_reserved(addr)) { |
| assert(perm_gen()->is_in(addr), |
| "addr should be in allocated part of perm gen"); |
| return perm_gen()->block_size(addr); |
| } |
| assert(false, "Some generation should contain the address"); |
| return 0; |
| } |
| |
| bool GenCollectedHeap::block_is_obj(const HeapWord* addr) const { |
| assert(is_in_reserved(addr), "block_is_obj of address outside of heap"); |
| assert(block_start(addr) == addr, "addr must be a block start"); |
| for (int i = 0; i < _n_gens; i++) { |
| if (_gens[i]->is_in_reserved(addr)) { |
| return _gens[i]->block_is_obj(addr); |
| } |
| } |
| if (perm_gen()->is_in_reserved(addr)) { |
| return perm_gen()->block_is_obj(addr); |
| } |
| assert(false, "Some generation should contain the address"); |
| return false; |
| } |
| |
| bool GenCollectedHeap::supports_tlab_allocation() const { |
| for (int i = 0; i < _n_gens; i += 1) { |
| if (_gens[i]->supports_tlab_allocation()) { |
| return true; |
| } |
| } |
| return false; |
| } |
| |
| size_t GenCollectedHeap::tlab_capacity(Thread* thr) const { |
| size_t result = 0; |
| for (int i = 0; i < _n_gens; i += 1) { |
| if (_gens[i]->supports_tlab_allocation()) { |
| result += _gens[i]->tlab_capacity(); |
| } |
| } |
| return result; |
| } |
| |
| size_t GenCollectedHeap::unsafe_max_tlab_alloc(Thread* thr) const { |
| size_t result = 0; |
| for (int i = 0; i < _n_gens; i += 1) { |
| if (_gens[i]->supports_tlab_allocation()) { |
| result += _gens[i]->unsafe_max_tlab_alloc(); |
| } |
| } |
| return result; |
| } |
| |
| HeapWord* GenCollectedHeap::allocate_new_tlab(size_t size) { |
| bool gc_overhead_limit_was_exceeded; |
| return collector_policy()->mem_allocate_work(size /* size */, |
| true /* is_tlab */, |
| &gc_overhead_limit_was_exceeded); |
| } |
| |
| // Requires "*prev_ptr" to be non-NULL. Deletes and a block of minimal size |
| // from the list headed by "*prev_ptr". |
| static ScratchBlock *removeSmallestScratch(ScratchBlock **prev_ptr) { |
| bool first = true; |
| size_t min_size = 0; // "first" makes this conceptually infinite. |
| ScratchBlock **smallest_ptr, *smallest; |
| ScratchBlock *cur = *prev_ptr; |
| while (cur) { |
| assert(*prev_ptr == cur, "just checking"); |
| if (first || cur->num_words < min_size) { |
| smallest_ptr = prev_ptr; |
| smallest = cur; |
| min_size = smallest->num_words; |
| first = false; |
| } |
| prev_ptr = &cur->next; |
| cur = cur->next; |
| } |
| smallest = *smallest_ptr; |
| *smallest_ptr = smallest->next; |
| return smallest; |
| } |
| |
| // Sort the scratch block list headed by res into decreasing size order, |
| // and set "res" to the result. |
| static void sort_scratch_list(ScratchBlock*& list) { |
| ScratchBlock* sorted = NULL; |
| ScratchBlock* unsorted = list; |
| while (unsorted) { |
| ScratchBlock *smallest = removeSmallestScratch(&unsorted); |
| smallest->next = sorted; |
| sorted = smallest; |
| } |
| list = sorted; |
| } |
| |
| ScratchBlock* GenCollectedHeap::gather_scratch(Generation* requestor, |
| size_t max_alloc_words) { |
| ScratchBlock* res = NULL; |
| for (int i = 0; i < _n_gens; i++) { |
| _gens[i]->contribute_scratch(res, requestor, max_alloc_words); |
| } |
| sort_scratch_list(res); |
| return res; |
| } |
| |
| void GenCollectedHeap::release_scratch() { |
| for (int i = 0; i < _n_gens; i++) { |
| _gens[i]->reset_scratch(); |
| } |
| } |
| |
| class GenPrepareForVerifyClosure: public GenCollectedHeap::GenClosure { |
| void do_generation(Generation* gen) { |
| gen->prepare_for_verify(); |
| } |
| }; |
| |
| void GenCollectedHeap::prepare_for_verify() { |
| ensure_parsability(false); // no need to retire TLABs |
| GenPrepareForVerifyClosure blk; |
| generation_iterate(&blk, false); |
| perm_gen()->prepare_for_verify(); |
| } |
| |
| |
| void GenCollectedHeap::generation_iterate(GenClosure* cl, |
| bool old_to_young) { |
| if (old_to_young) { |
| for (int i = _n_gens-1; i >= 0; i--) { |
| cl->do_generation(_gens[i]); |
| } |
| } else { |
| for (int i = 0; i < _n_gens; i++) { |
| cl->do_generation(_gens[i]); |
| } |
| } |
| } |
| |
| void GenCollectedHeap::space_iterate(SpaceClosure* cl) { |
| for (int i = 0; i < _n_gens; i++) { |
| _gens[i]->space_iterate(cl, true); |
| } |
| perm_gen()->space_iterate(cl, true); |
| } |
| |
| bool GenCollectedHeap::is_maximal_no_gc() const { |
| for (int i = 0; i < _n_gens; i++) { // skip perm gen |
| if (!_gens[i]->is_maximal_no_gc()) { |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| void GenCollectedHeap::save_marks() { |
| for (int i = 0; i < _n_gens; i++) { |
| _gens[i]->save_marks(); |
| } |
| perm_gen()->save_marks(); |
| } |
| |
| void GenCollectedHeap::compute_new_generation_sizes(int collectedGen) { |
| for (int i = 0; i <= collectedGen; i++) { |
| _gens[i]->compute_new_size(); |
| } |
| } |
| |
| GenCollectedHeap* GenCollectedHeap::heap() { |
| assert(_gch != NULL, "Uninitialized access to GenCollectedHeap::heap()"); |
| assert(_gch->kind() == CollectedHeap::GenCollectedHeap, "not a generational heap"); |
| return _gch; |
| } |
| |
| |
| void GenCollectedHeap::prepare_for_compaction() { |
| Generation* scanning_gen = _gens[_n_gens-1]; |
| // Start by compacting into same gen. |
| CompactPoint cp(scanning_gen, NULL, NULL); |
| while (scanning_gen != NULL) { |
| scanning_gen->prepare_for_compaction(&cp); |
| scanning_gen = prev_gen(scanning_gen); |
| } |
| } |
| |
| GCStats* GenCollectedHeap::gc_stats(int level) const { |
| return _gens[level]->gc_stats(); |
| } |
| |
| void GenCollectedHeap::verify(bool silent, VerifyOption option /* ignored */) { |
| if (!silent) { |
| gclog_or_tty->print("permgen "); |
| } |
| perm_gen()->verify(); |
| for (int i = _n_gens-1; i >= 0; i--) { |
| Generation* g = _gens[i]; |
| if (!silent) { |
| gclog_or_tty->print(g->name()); |
| gclog_or_tty->print(" "); |
| } |
| g->verify(); |
| } |
| if (!silent) { |
| gclog_or_tty->print("remset "); |
| } |
| rem_set()->verify(); |
| } |
| |
| void GenCollectedHeap::print_on(outputStream* st) const { |
| for (int i = 0; i < _n_gens; i++) { |
| _gens[i]->print_on(st); |
| } |
| perm_gen()->print_on(st); |
| } |
| |
| void GenCollectedHeap::gc_threads_do(ThreadClosure* tc) const { |
| if (workers() != NULL) { |
| workers()->threads_do(tc); |
| } |
| #ifndef SERIALGC |
| if (UseConcMarkSweepGC) { |
| ConcurrentMarkSweepThread::threads_do(tc); |
| } |
| #endif // SERIALGC |
| } |
| |
| void GenCollectedHeap::print_gc_threads_on(outputStream* st) const { |
| #ifndef SERIALGC |
| if (UseParNewGC) { |
| workers()->print_worker_threads_on(st); |
| } |
| if (UseConcMarkSweepGC) { |
| ConcurrentMarkSweepThread::print_all_on(st); |
| } |
| #endif // SERIALGC |
| } |
| |
| void GenCollectedHeap::print_tracing_info() const { |
| if (TraceGen0Time) { |
| get_gen(0)->print_summary_info(); |
| } |
| if (TraceGen1Time) { |
| get_gen(1)->print_summary_info(); |
| } |
| } |
| |
| void GenCollectedHeap::print_heap_change(size_t prev_used) const { |
| if (PrintGCDetails && Verbose) { |
| gclog_or_tty->print(" " SIZE_FORMAT |
| "->" SIZE_FORMAT |
| "(" SIZE_FORMAT ")", |
| prev_used, used(), capacity()); |
| } else { |
| gclog_or_tty->print(" " SIZE_FORMAT "K" |
| "->" SIZE_FORMAT "K" |
| "(" SIZE_FORMAT "K)", |
| prev_used / K, used() / K, capacity() / K); |
| } |
| } |
| |
| //New method to print perm gen info with PrintGCDetails flag |
| void GenCollectedHeap::print_perm_heap_change(size_t perm_prev_used) const { |
| gclog_or_tty->print(", [%s :", perm_gen()->short_name()); |
| perm_gen()->print_heap_change(perm_prev_used); |
| gclog_or_tty->print("]"); |
| } |
| |
| class GenGCPrologueClosure: public GenCollectedHeap::GenClosure { |
| private: |
| bool _full; |
| public: |
| void do_generation(Generation* gen) { |
| gen->gc_prologue(_full); |
| } |
| GenGCPrologueClosure(bool full) : _full(full) {}; |
| }; |
| |
| void GenCollectedHeap::gc_prologue(bool full) { |
| assert(InlineCacheBuffer::is_empty(), "should have cleaned up ICBuffer"); |
| |
| always_do_update_barrier = false; |
| // Fill TLAB's and such |
| CollectedHeap::accumulate_statistics_all_tlabs(); |
| ensure_parsability(true); // retire TLABs |
| |
| // Call allocation profiler |
| AllocationProfiler::iterate_since_last_gc(); |
| // Walk generations |
| GenGCPrologueClosure blk(full); |
| generation_iterate(&blk, false); // not old-to-young. |
| perm_gen()->gc_prologue(full); |
| }; |
| |
| class GenGCEpilogueClosure: public GenCollectedHeap::GenClosure { |
| private: |
| bool _full; |
| public: |
| void do_generation(Generation* gen) { |
| gen->gc_epilogue(_full); |
| } |
| GenGCEpilogueClosure(bool full) : _full(full) {}; |
| }; |
| |
| void GenCollectedHeap::gc_epilogue(bool full) { |
| #ifdef COMPILER2 |
| assert(DerivedPointerTable::is_empty(), "derived pointer present"); |
| size_t actual_gap = pointer_delta((HeapWord*) (max_uintx-3), *(end_addr())); |
| guarantee(actual_gap > (size_t)FastAllocateSizeLimit, "inline allocation wraps"); |
| #endif /* COMPILER2 */ |
| |
| resize_all_tlabs(); |
| |
| GenGCEpilogueClosure blk(full); |
| generation_iterate(&blk, false); // not old-to-young. |
| perm_gen()->gc_epilogue(full); |
| |
| if (!CleanChunkPoolAsync) { |
| Chunk::clean_chunk_pool(); |
| } |
| |
| always_do_update_barrier = UseConcMarkSweepGC; |
| }; |
| |
| #ifndef PRODUCT |
| class GenGCSaveTopsBeforeGCClosure: public GenCollectedHeap::GenClosure { |
| private: |
| public: |
| void do_generation(Generation* gen) { |
| gen->record_spaces_top(); |
| } |
| }; |
| |
| void GenCollectedHeap::record_gen_tops_before_GC() { |
| if (ZapUnusedHeapArea) { |
| GenGCSaveTopsBeforeGCClosure blk; |
| generation_iterate(&blk, false); // not old-to-young. |
| perm_gen()->record_spaces_top(); |
| } |
| } |
| #endif // not PRODUCT |
| |
| class GenEnsureParsabilityClosure: public GenCollectedHeap::GenClosure { |
| public: |
| void do_generation(Generation* gen) { |
| gen->ensure_parsability(); |
| } |
| }; |
| |
| void GenCollectedHeap::ensure_parsability(bool retire_tlabs) { |
| CollectedHeap::ensure_parsability(retire_tlabs); |
| GenEnsureParsabilityClosure ep_cl; |
| generation_iterate(&ep_cl, false); |
| perm_gen()->ensure_parsability(); |
| } |
| |
| oop GenCollectedHeap::handle_failed_promotion(Generation* gen, |
| oop obj, |
| size_t obj_size) { |
| assert(obj_size == (size_t)obj->size(), "bad obj_size passed in"); |
| HeapWord* result = NULL; |
| |
| // First give each higher generation a chance to allocate the promoted object. |
| Generation* allocator = next_gen(gen); |
| if (allocator != NULL) { |
| do { |
| result = allocator->allocate(obj_size, false); |
| } while (result == NULL && (allocator = next_gen(allocator)) != NULL); |
| } |
| |
| if (result == NULL) { |
| // Then give gen and higher generations a chance to expand and allocate the |
| // object. |
| do { |
| result = gen->expand_and_allocate(obj_size, false); |
| } while (result == NULL && (gen = next_gen(gen)) != NULL); |
| } |
| |
| if (result != NULL) { |
| Copy::aligned_disjoint_words((HeapWord*)obj, result, obj_size); |
| } |
| return oop(result); |
| } |
| |
| class GenTimeOfLastGCClosure: public GenCollectedHeap::GenClosure { |
| jlong _time; // in ms |
| jlong _now; // in ms |
| |
| public: |
| GenTimeOfLastGCClosure(jlong now) : _time(now), _now(now) { } |
| |
| jlong time() { return _time; } |
| |
| void do_generation(Generation* gen) { |
| _time = MIN2(_time, gen->time_of_last_gc(_now)); |
| } |
| }; |
| |
| jlong GenCollectedHeap::millis_since_last_gc() { |
| // We need a monotonically non-deccreasing time in ms but |
| // os::javaTimeMillis() does not guarantee monotonicity. |
| jlong now = os::javaTimeNanos() / NANOSECS_PER_MILLISEC; |
| GenTimeOfLastGCClosure tolgc_cl(now); |
| // iterate over generations getting the oldest |
| // time that a generation was collected |
| generation_iterate(&tolgc_cl, false); |
| tolgc_cl.do_generation(perm_gen()); |
| |
| // javaTimeNanos() is guaranteed to be monotonically non-decreasing |
| // provided the underlying platform provides such a time source |
| // (and it is bug free). So we still have to guard against getting |
| // back a time later than 'now'. |
| jlong retVal = now - tolgc_cl.time(); |
| if (retVal < 0) { |
| NOT_PRODUCT(warning("time warp: "INT64_FORMAT, retVal);) |
| return 0; |
| } |
| return retVal; |
| } |