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 #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 "utilities/ostream.hpp"
  38 
  39 class AdjoiningGenerations;
  40 class GCHeapSummary;
  41 class GCTaskManager;
  42 class PSAdaptiveSizePolicy;
  43 class PSHeapSummary;
  44 
  45 class ParallelScavengeHeap : public CollectedHeap {
  46   friend class VMStructs;
  47  private:
  48   static PSYoungGen* _young_gen;
  49   static PSOldGen*   _old_gen;
  50 
  51   // Sizing policy for entire heap
  52   static PSAdaptiveSizePolicy*       _size_policy;
  53   static PSGCAdaptivePolicyCounters* _gc_policy_counters;
  54 
  55   static ParallelScavengeHeap* _psh;
  56 
  57   GenerationSizer* _collector_policy;
  58 
  59   // Collection of generations that are adjacent in the
  60   // space reserved for the heap.
  61   AdjoiningGenerations* _gens;
  62   unsigned int _death_march_count;
  63 
  64   // The task manager
  65   static GCTaskManager* _gc_task_manager;
  66 
  67   void trace_heap(GCWhen::Type when, const GCTracer* tracer);
  68 
  69  protected:
  70   static inline size_t total_invocations();
  71   HeapWord* allocate_new_tlab(size_t size);
  72 
  73   inline bool should_alloc_in_eden(size_t size) const;
  74   inline void death_march_check(HeapWord* const result, size_t size);
  75   HeapWord* mem_allocate_old_gen(size_t size);
  76 
  77  public:
  78   ParallelScavengeHeap() : CollectedHeap(), _death_march_count(0) { }
  79 
  80   // For use by VM operations
  81   enum CollectionType {
  82     Scavenge,
  83     MarkSweep
  84   };
  85 
  86   ParallelScavengeHeap::Name kind() const {
  87     return CollectedHeap::ParallelScavengeHeap;
  88   }
  89 
  90   virtual CollectorPolicy* collector_policy() const { return (CollectorPolicy*) _collector_policy; }
  91 
  92   static PSYoungGen* young_gen() { return _young_gen; }
  93   static PSOldGen* old_gen()     { return _old_gen; }
  94 
  95   virtual PSAdaptiveSizePolicy* size_policy() { return _size_policy; }
  96 
  97   static PSGCAdaptivePolicyCounters* gc_policy_counters() { return _gc_policy_counters; }
  98 
  99   static ParallelScavengeHeap* heap();
 100 
 101   static GCTaskManager* const gc_task_manager() { return _gc_task_manager; }
 102 
 103   AdjoiningGenerations* gens() { return _gens; }
 104 
 105   // Returns JNI_OK on success
 106   virtual jint initialize();
 107 
 108   void post_initialize();
 109   void update_counters();
 110 
 111   // The alignment used for the various areas
 112   size_t space_alignment()      { return _collector_policy->space_alignment(); }
 113   size_t generation_alignment() { return _collector_policy->gen_alignment(); }
 114 
 115   // Return the (conservative) maximum heap alignment
 116   static size_t conservative_max_heap_alignment() {
 117     return CollectorPolicy::compute_heap_alignment();
 118   }
 119 
 120   size_t capacity() const;
 121   size_t used() const;
 122 
 123   // Return "true" if all generations have reached the
 124   // maximal committed limit that they can reach, without a garbage
 125   // collection.
 126   virtual bool is_maximal_no_gc() const;
 127 
 128   // Return true if the reference points to an object that
 129   // can be moved in a partial collection.  For currently implemented
 130   // generational collectors that means during a collection of
 131   // the young gen.
 132   virtual bool is_scavengable(const void* addr);
 133 
 134   // Does this heap support heap inspection? (+PrintClassHistogram)
 135   bool supports_heap_inspection() const { return true; }
 136 
 137   size_t max_capacity() const;
 138 
 139   // Whether p is in the allocated part of the heap
 140   bool is_in(const void* p) const;
 141 
 142   bool is_in_reserved(const void* p) const;
 143 
 144 #ifdef ASSERT
 145   virtual bool is_in_partial_collection(const void *p);
 146 #endif
 147 
 148   bool is_in_young(oop p);  // reserved part
 149   bool is_in_old(oop p);    // reserved part
 150 
 151   // Memory allocation.   "gc_time_limit_was_exceeded" will
 152   // be set to true if the adaptive size policy determine that
 153   // an excessive amount of time is being spent doing collections
 154   // and caused a NULL to be returned.  If a NULL is not returned,
 155   // "gc_time_limit_was_exceeded" has an undefined meaning.
 156   HeapWord* mem_allocate(size_t size, bool* gc_overhead_limit_was_exceeded);
 157 
 158   // Allocation attempt(s) during a safepoint. It should never be called
 159   // to allocate a new TLAB as this allocation might be satisfied out
 160   // of the old generation.
 161   HeapWord* failed_mem_allocate(size_t size);
 162 
 163   // Support for System.gc()
 164   void collect(GCCause::Cause cause);
 165 
 166   // These also should be called by the vm thread at a safepoint (e.g., from a
 167   // VM operation).
 168   //
 169   // The first collects the young generation only, unless the scavenge fails; it
 170   // will then attempt a full gc.  The second collects the entire heap; if
 171   // maximum_compaction is true, it will compact everything and clear all soft
 172   // references.
 173   inline void invoke_scavenge();
 174 
 175   // Perform a full collection
 176   virtual void do_full_collection(bool clear_all_soft_refs);
 177 
 178   bool supports_inline_contig_alloc() const { return !UseNUMA; }
 179 
 180   HeapWord** top_addr() const { return !UseNUMA ? young_gen()->top_addr() : (HeapWord**)-1; }
 181   HeapWord** end_addr() const { return !UseNUMA ? young_gen()->end_addr() : (HeapWord**)-1; }
 182 
 183   void ensure_parsability(bool retire_tlabs);
 184   void accumulate_statistics_all_tlabs();
 185   void resize_all_tlabs();
 186 
 187   bool supports_tlab_allocation() const { return true; }
 188 
 189   size_t tlab_capacity(Thread* thr) const;
 190   size_t tlab_used(Thread* thr) const;
 191   size_t unsafe_max_tlab_alloc(Thread* thr) const;
 192 
 193   // Can a compiler initialize a new object without store barriers?
 194   // This permission only extends from the creation of a new object
 195   // via a TLAB up to the first subsequent safepoint.
 196   virtual bool can_elide_tlab_store_barriers() const {
 197     return true;
 198   }
 199 
 200   virtual bool card_mark_must_follow_store() const {
 201     return false;
 202   }
 203 
 204   // Return true if we don't we need a store barrier for
 205   // initializing stores to an object at this address.
 206   virtual bool can_elide_initializing_store_barrier(oop new_obj);
 207 
 208   void oop_iterate(ExtendedOopClosure* cl);
 209   void object_iterate(ObjectClosure* cl);
 210   void safe_object_iterate(ObjectClosure* cl) { object_iterate(cl); }
 211 
 212   HeapWord* block_start(const void* addr) const;
 213   size_t block_size(const HeapWord* addr) const;
 214   bool block_is_obj(const HeapWord* addr) const;
 215 
 216   jlong millis_since_last_gc();
 217 
 218   void prepare_for_verify();
 219   PSHeapSummary create_ps_heap_summary();
 220   virtual void print_on(outputStream* st) const;
 221   virtual void print_on_error(outputStream* st) const;
 222   virtual void print_gc_threads_on(outputStream* st) const;
 223   virtual void gc_threads_do(ThreadClosure* tc) const;
 224   virtual void print_tracing_info() const;
 225 
 226   void verify(bool silent, VerifyOption option /* ignored */);
 227 
 228   void print_heap_change(size_t prev_used);
 229 
 230   // Resize the young generation.  The reserved space for the
 231   // generation may be expanded in preparation for the resize.
 232   void resize_young_gen(size_t eden_size, size_t survivor_size);
 233 
 234   // Resize the old generation.  The reserved space for the
 235   // generation may be expanded in preparation for the resize.
 236   void resize_old_gen(size_t desired_free_space);
 237 
 238   // Save the tops of the spaces in all generations
 239   void record_gen_tops_before_GC() PRODUCT_RETURN;
 240 
 241   // Mangle the unused parts of all spaces in the heap
 242   void gen_mangle_unused_area() PRODUCT_RETURN;
 243 
 244   // Call these in sequential code around the processing of strong roots.
 245   class ParStrongRootsScope : public MarkingCodeBlobClosure::MarkScope {
 246    public:
 247     ParStrongRootsScope();
 248     ~ParStrongRootsScope();
 249   };
 250 };
 251 
 252 #endif // SHARE_VM_GC_IMPLEMENTATION_PARALLELSCAVENGE_PARALLELSCAVENGEHEAP_HPP