1 /*
   2  * Copyright (c) 2001, 2015, 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
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  24 
  25 #ifndef SHARE_VM_GC_IMPLEMENTATION_PARALLELSCAVENGE_PARALLELSCAVENGEHEAP_HPP
  26 #define SHARE_VM_GC_IMPLEMENTATION_PARALLELSCAVENGE_PARALLELSCAVENGEHEAP_HPP
  27 
  28 #include "gc_implementation/parallelScavenge/generationSizer.hpp"
  29 #include "gc_implementation/parallelScavenge/objectStartArray.hpp"
  30 #include "gc_implementation/parallelScavenge/psGCAdaptivePolicyCounters.hpp"
  31 #include "gc_implementation/parallelScavenge/psOldGen.hpp"
  32 #include "gc_implementation/parallelScavenge/psYoungGen.hpp"
  33 #include "gc_implementation/shared/gcPolicyCounters.hpp"
  34 #include "gc_implementation/shared/gcWhen.hpp"
  35 #include "gc_interface/collectedHeap.inline.hpp"
  36 #include "memory/collectorPolicy.hpp"
  37 #include "memory/strongRootsScope.hpp"
  38 #include "utilities/ostream.hpp"
  39 
  40 class AdjoiningGenerations;
  41 class GCHeapSummary;
  42 class GCTaskManager;
  43 class PSAdaptiveSizePolicy;
  44 class PSHeapSummary;
  45 
  46 class ParallelScavengeHeap : public CollectedHeap {
  47   friend class VMStructs;
  48  private:
  49   static PSYoungGen* _young_gen;
  50   static PSOldGen*   _old_gen;
  51 
  52   // Sizing policy for entire heap
  53   static PSAdaptiveSizePolicy*       _size_policy;
  54   static PSGCAdaptivePolicyCounters* _gc_policy_counters;
  55 
  56   static ParallelScavengeHeap* _psh;
  57 
  58   GenerationSizer* _collector_policy;
  59 
  60   // Collection of generations that are adjacent in the
  61   // space reserved for the heap.
  62   AdjoiningGenerations* _gens;
  63   unsigned int _death_march_count;
  64 
  65   // The task manager
  66   static GCTaskManager* _gc_task_manager;
  67 
  68   void trace_heap(GCWhen::Type when, const GCTracer* tracer);
  69 
  70  protected:
  71   static inline size_t total_invocations();
  72   HeapWord* allocate_new_tlab(size_t size);
  73 
  74   inline bool should_alloc_in_eden(size_t size) const;
  75   inline void death_march_check(HeapWord* const result, size_t size);
  76   HeapWord* mem_allocate_old_gen(size_t size);
  77 
  78  public:
  79   ParallelScavengeHeap() : CollectedHeap(), _death_march_count(0) { }
  80 
  81   // For use by VM operations
  82   enum CollectionType {
  83     Scavenge,
  84     MarkSweep
  85   };
  86 
  87   virtual Name kind() const {
  88     return CollectedHeap::ParallelScavengeHeap;
  89   }
  90 
  91   virtual CollectorPolicy* collector_policy() const { return (CollectorPolicy*) _collector_policy; }
  92 
  93   static PSYoungGen* young_gen() { return _young_gen; }
  94   static PSOldGen* old_gen()     { return _old_gen; }
  95 
  96   virtual PSAdaptiveSizePolicy* size_policy() { return _size_policy; }
  97 
  98   static PSGCAdaptivePolicyCounters* gc_policy_counters() { return _gc_policy_counters; }
  99 
 100   static ParallelScavengeHeap* heap();
 101 
 102   static GCTaskManager* const gc_task_manager() { return _gc_task_manager; }
 103 
 104   AdjoiningGenerations* gens() { return _gens; }
 105 
 106   // Returns JNI_OK on success
 107   virtual jint initialize();
 108 
 109   void post_initialize();
 110   void update_counters();
 111 
 112   // The alignment used for the various areas
 113   size_t space_alignment()      { return _collector_policy->space_alignment(); }
 114   size_t generation_alignment() { return _collector_policy->gen_alignment(); }
 115 
 116   // Return the (conservative) maximum heap alignment
 117   static size_t conservative_max_heap_alignment() {
 118     return CollectorPolicy::compute_heap_alignment();
 119   }
 120 
 121   size_t capacity() const;
 122   size_t used() const;
 123 
 124   // Return "true" if all generations have reached the
 125   // maximal committed limit that they can reach, without a garbage
 126   // collection.
 127   virtual bool is_maximal_no_gc() const;
 128 
 129   // Return true if the reference points to an object that
 130   // can be moved in a partial collection.  For currently implemented
 131   // generational collectors that means during a collection of
 132   // the young gen.
 133   virtual bool is_scavengable(const void* addr);
 134 
 135   // Does this heap support heap inspection? (+PrintClassHistogram)
 136   bool supports_heap_inspection() const { return true; }
 137 
 138   size_t max_capacity() const;
 139 
 140   // Whether p is in the allocated part of the heap
 141   bool is_in(const void* p) const;
 142 
 143   bool is_in_reserved(const void* p) const;
 144 
 145   bool is_in_young(oop p);  // reserved part
 146   bool is_in_old(oop p);    // reserved part
 147 
 148   // Memory allocation.   "gc_time_limit_was_exceeded" will
 149   // be set to true if the adaptive size policy determine that
 150   // an excessive amount of time is being spent doing collections
 151   // and caused a NULL to be returned.  If a NULL is not returned,
 152   // "gc_time_limit_was_exceeded" has an undefined meaning.
 153   HeapWord* mem_allocate(size_t size, bool* gc_overhead_limit_was_exceeded);
 154 
 155   // Allocation attempt(s) during a safepoint. It should never be called
 156   // to allocate a new TLAB as this allocation might be satisfied out
 157   // of the old generation.
 158   HeapWord* failed_mem_allocate(size_t size);
 159 
 160   // Support for System.gc()
 161   void collect(GCCause::Cause cause);
 162 
 163   // These also should be called by the vm thread at a safepoint (e.g., from a
 164   // VM operation).
 165   //
 166   // The first collects the young generation only, unless the scavenge fails; it
 167   // will then attempt a full gc.  The second collects the entire heap; if
 168   // maximum_compaction is true, it will compact everything and clear all soft
 169   // references.
 170   inline void invoke_scavenge();
 171 
 172   // Perform a full collection
 173   virtual void do_full_collection(bool clear_all_soft_refs);
 174 
 175   bool supports_inline_contig_alloc() const { return !UseNUMA; }
 176 
 177   HeapWord** top_addr() const { return !UseNUMA ? young_gen()->top_addr() : (HeapWord**)-1; }
 178   HeapWord** end_addr() const { return !UseNUMA ? young_gen()->end_addr() : (HeapWord**)-1; }
 179 
 180   void ensure_parsability(bool retire_tlabs);
 181   void accumulate_statistics_all_tlabs();
 182   void resize_all_tlabs();
 183 
 184   bool supports_tlab_allocation() const { return true; }
 185 
 186   size_t tlab_capacity(Thread* thr) const;
 187   size_t tlab_used(Thread* thr) const;
 188   size_t unsafe_max_tlab_alloc(Thread* thr) const;
 189 
 190   // Can a compiler initialize a new object without store barriers?
 191   // This permission only extends from the creation of a new object
 192   // via a TLAB up to the first subsequent safepoint.
 193   virtual bool can_elide_tlab_store_barriers() const {
 194     return true;
 195   }
 196 
 197   virtual bool card_mark_must_follow_store() const {
 198     return false;
 199   }
 200 
 201   // Return true if we don't we need a store barrier for
 202   // initializing stores to an object at this address.
 203   virtual bool can_elide_initializing_store_barrier(oop new_obj);
 204 
 205   void object_iterate(ObjectClosure* cl);
 206   void safe_object_iterate(ObjectClosure* cl) { object_iterate(cl); }
 207 
 208   HeapWord* block_start(const void* addr) const;
 209   size_t block_size(const HeapWord* addr) const;
 210   bool block_is_obj(const HeapWord* addr) const;
 211 
 212   jlong millis_since_last_gc();
 213 
 214   void prepare_for_verify();
 215   PSHeapSummary create_ps_heap_summary();
 216   virtual void print_on(outputStream* st) const;
 217   virtual void print_on_error(outputStream* st) const;
 218   virtual void print_gc_threads_on(outputStream* st) const;
 219   virtual void gc_threads_do(ThreadClosure* tc) const;
 220   virtual void print_tracing_info() const;
 221 
 222   void verify(bool silent, VerifyOption option /* ignored */);
 223 
 224   void print_heap_change(size_t prev_used);
 225 
 226   // Resize the young generation.  The reserved space for the
 227   // generation may be expanded in preparation for the resize.
 228   void resize_young_gen(size_t eden_size, size_t survivor_size);
 229 
 230   // Resize the old generation.  The reserved space for the
 231   // generation may be expanded in preparation for the resize.
 232   void resize_old_gen(size_t desired_free_space);
 233 
 234   // Save the tops of the spaces in all generations
 235   void record_gen_tops_before_GC() PRODUCT_RETURN;
 236 
 237   // Mangle the unused parts of all spaces in the heap
 238   void gen_mangle_unused_area() PRODUCT_RETURN;
 239 
 240   // Call these in sequential code around the processing of strong roots.
 241   class ParStrongRootsScope : public MarkScope {
 242    public:
 243     ParStrongRootsScope();
 244     ~ParStrongRootsScope();
 245   };
 246 };
 247 
 248 #endif // SHARE_VM_GC_IMPLEMENTATION_PARALLELSCAVENGE_PARALLELSCAVENGEHEAP_HPP