1 /*
   2  * Copyright (c) 2001, 2012, 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/objectStartArray.hpp"
  29 #include "gc_implementation/parallelScavenge/psGCAdaptivePolicyCounters.hpp"
  30 #include "gc_implementation/parallelScavenge/psOldGen.hpp"
  31 #include "gc_implementation/parallelScavenge/psYoungGen.hpp"
  32 #include "gc_implementation/shared/gcPolicyCounters.hpp"
  33 #include "gc_interface/collectedHeap.inline.hpp"
  34 #include "utilities/ostream.hpp"
  35 
  36 class AdjoiningGenerations;
  37 class GCTaskManager;
  38 class PSAdaptiveSizePolicy;
  39 class GenerationSizer;
  40 class CollectorPolicy;
  41 
  42 class ParallelScavengeHeap : public CollectedHeap {
  43   friend class VMStructs;
  44  private:
  45   static PSYoungGen* _young_gen;
  46   static PSOldGen*   _old_gen;
  47 
  48   // Sizing policy for entire heap
  49   static PSAdaptiveSizePolicy* _size_policy;
  50   static PSGCAdaptivePolicyCounters*   _gc_policy_counters;
  51 
  52   static ParallelScavengeHeap* _psh;
  53 
  54   size_t _young_gen_alignment;
  55   size_t _old_gen_alignment;
  56 
  57   GenerationSizer* _collector_policy;
  58 
  59   inline size_t set_alignment(size_t& var, size_t val);
  60 
  61   // Collection of generations that are adjacent in the
  62   // space reserved for the heap.
  63   AdjoiningGenerations* _gens;
  64   unsigned int _death_march_count;
  65 
  66   static GCTaskManager*          _gc_task_manager;      // The task manager.
  67 
  68  protected:
  69   static inline size_t total_invocations();
  70   HeapWord* allocate_new_tlab(size_t size);
  71 
  72   inline bool should_alloc_in_eden(size_t size) const;
  73   inline void death_march_check(HeapWord* const result, size_t size);
  74   HeapWord* mem_allocate_old_gen(size_t size);
  75 
  76  public:
  77   ParallelScavengeHeap() : CollectedHeap() {
  78     _death_march_count = 0;
  79     set_alignment(_young_gen_alignment, intra_heap_alignment());
  80     set_alignment(_old_gen_alignment, intra_heap_alignment());
  81   }
  82 
  83   // For use by VM operations
  84   enum CollectionType {
  85     Scavenge,
  86     MarkSweep
  87   };
  88 
  89   ParallelScavengeHeap::Name kind() const {
  90     return CollectedHeap::ParallelScavengeHeap;
  91   }
  92 
  93   virtual CollectorPolicy* collector_policy() const { return (CollectorPolicy*) _collector_policy; }
  94 
  95   static PSYoungGen* young_gen()     { return _young_gen; }
  96   static PSOldGen* old_gen()         { return _old_gen; }
  97 
  98   virtual PSAdaptiveSizePolicy* size_policy() { return _size_policy; }
  99 
 100   static PSGCAdaptivePolicyCounters* gc_policy_counters() { return _gc_policy_counters; }
 101 
 102   static ParallelScavengeHeap* heap();
 103 
 104   static GCTaskManager* const gc_task_manager() { return _gc_task_manager; }
 105 
 106   AdjoiningGenerations* gens() { return _gens; }
 107 
 108   // Returns JNI_OK on success
 109   virtual jint initialize();
 110 
 111   void post_initialize();
 112   void update_counters();
 113   // The alignment used for the various generations.
 114   size_t young_gen_alignment() const { return _young_gen_alignment; }
 115   size_t old_gen_alignment()  const { return _old_gen_alignment; }
 116 
 117   // The alignment used for eden and survivors within the young gen
 118   // and for boundary between young gen and old gen.
 119   size_t intra_heap_alignment() const { return 64 * K * HeapWordSize; }
 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 #ifdef ASSERT
 146   virtual bool is_in_partial_collection(const void *p);
 147 #endif
 148 
 149   bool is_in_young(oop p);        // reserved part
 150   bool is_in_old(oop p);          // reserved part
 151 
 152   // Memory allocation.   "gc_time_limit_was_exceeded" will
 153   // be set to true if the adaptive size policy determine that
 154   // an excessive amount of time is being spent doing collections
 155   // and caused a NULL to be returned.  If a NULL is not returned,
 156   // "gc_time_limit_was_exceeded" has an undefined meaning.
 157   HeapWord* mem_allocate(size_t size,
 158                          bool* gc_overhead_limit_was_exceeded);
 159 
 160   // Allocation attempt(s) during a safepoint. It should never be called
 161   // to allocate a new TLAB as this allocation might be satisfied out
 162   // of the old generation.
 163   HeapWord* failed_mem_allocate(size_t size);
 164 
 165   // Support for System.gc()
 166   void collect(GCCause::Cause cause);
 167 
 168   // These also should be called by the vm thread at a safepoint (e.g., from a
 169   // VM operation).
 170   //
 171   // The first collects the young generation only, unless the scavenge fails; it
 172   // will then attempt a full gc.  The second collects the entire heap; if
 173   // maximum_compaction is true, it will compact everything and clear all soft
 174   // references.
 175   inline void invoke_scavenge();
 176 
 177   // Perform a full collection
 178   virtual void do_full_collection(bool clear_all_soft_refs);
 179 
 180   bool supports_inline_contig_alloc() const { return !UseNUMA; }
 181 
 182   HeapWord** top_addr() const { return !UseNUMA ? young_gen()->top_addr() : (HeapWord**)-1; }
 183   HeapWord** end_addr() const { return !UseNUMA ? young_gen()->end_addr() : (HeapWord**)-1; }
 184 
 185   void ensure_parsability(bool retire_tlabs);
 186   void accumulate_statistics_all_tlabs();
 187   void resize_all_tlabs();
 188 
 189   size_t unsafe_max_alloc();
 190 
 191   bool supports_tlab_allocation() const { return true; }
 192 
 193   size_t tlab_capacity(Thread* thr) const;
 194   size_t unsafe_max_tlab_alloc(Thread* thr) const;
 195 
 196   // Can a compiler initialize a new object without store barriers?
 197   // This permission only extends from the creation of a new object
 198   // via a TLAB up to the first subsequent safepoint.
 199   virtual bool can_elide_tlab_store_barriers() const {
 200     return true;
 201   }
 202 
 203   virtual bool card_mark_must_follow_store() const {
 204     return false;
 205   }
 206 
 207   // Return true if we don't we need a store barrier for
 208   // initializing stores to an object at this address.
 209   virtual bool can_elide_initializing_store_barrier(oop new_obj);
 210 
 211   void oop_iterate(ExtendedOopClosure* cl);
 212   void object_iterate(ObjectClosure* cl);
 213   void safe_object_iterate(ObjectClosure* cl) { object_iterate(cl); }
 214 
 215   HeapWord* block_start(const void* addr) const;
 216   size_t block_size(const HeapWord* addr) const;
 217   bool block_is_obj(const HeapWord* addr) const;
 218 
 219   jlong millis_since_last_gc();
 220 
 221   void prepare_for_verify();
 222   virtual void print_on(outputStream* st) const;
 223   virtual void print_on_error(outputStream* st) const;
 224   virtual void print_gc_threads_on(outputStream* st) const;
 225   virtual void gc_threads_do(ThreadClosure* tc) const;
 226   virtual void print_tracing_info() const;
 227 
 228   void verify(bool silent, VerifyOption option /* ignored */);
 229 
 230   void print_heap_change(size_t prev_used);
 231 
 232   // Resize the young generation.  The reserved space for the
 233   // generation may be expanded in preparation for the resize.
 234   void resize_young_gen(size_t eden_size, size_t survivor_size);
 235 
 236   // Resize the old generation.  The reserved space for the
 237   // generation may be expanded in preparation for the resize.
 238   void resize_old_gen(size_t desired_free_space);
 239 
 240   // Save the tops of the spaces in all generations
 241   void record_gen_tops_before_GC() PRODUCT_RETURN;
 242 
 243   // Mangle the unused parts of all spaces in the heap
 244   void gen_mangle_unused_area() PRODUCT_RETURN;
 245 
 246   // Call these in sequential code around the processing of strong roots.
 247   class ParStrongRootsScope : public MarkingCodeBlobClosure::MarkScope {
 248   public:
 249     ParStrongRootsScope();
 250     ~ParStrongRootsScope();
 251   };
 252 };
 253 
 254 inline size_t ParallelScavengeHeap::set_alignment(size_t& var, size_t val)
 255 {
 256   assert(is_power_of_2((intptr_t)val), "must be a power of 2");
 257   var = round_to(val, intra_heap_alignment());
 258   return var;
 259 }
 260 
 261 #endif // SHARE_VM_GC_IMPLEMENTATION_PARALLELSCAVENGE_PARALLELSCAVENGEHEAP_HPP