tenuredGeneration.hpp revision 8413:92457dfb91bd 
1/*
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3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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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
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14 *
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24
25#ifndef SHARE_VM_GC_SERIAL_TENUREDGENERATION_HPP
26#define SHARE_VM_GC_SERIAL_TENUREDGENERATION_HPP
27
28#include "gc/serial/cSpaceCounters.hpp"
29#include "gc/shared/cardGeneration.hpp"
30#include "gc/shared/gcStats.hpp"
31#include "gc/shared/generationCounters.hpp"
32#include "utilities/macros.hpp"
33
34// TenuredGeneration models the heap containing old (promoted/tenured) objects
35// contained in a single contiguous space.
36//
37// Garbage collection is performed using mark-compact.
38
39class TenuredGeneration: public CardGeneration {
40  friend class VMStructs;
41  // Abstractly, this is a subtype that gets access to protected fields.
42  friend class VM_PopulateDumpSharedSpace;
43
44 protected:
45  ContiguousSpace*  _the_space;       // Actual space holding objects
46
47  GenerationCounters*   _gen_counters;
48  CSpaceCounters*       _space_counters;
49
50  // Allocation failure
51  virtual bool expand(size_t bytes, size_t expand_bytes);
52
53  // Accessing spaces
54  ContiguousSpace* space() const { return _the_space; }
55
56  void assert_correct_size_change_locking();
57 public:
58  TenuredGeneration(ReservedSpace rs, size_t initial_byte_size,
59                               int level, GenRemSet* remset);
60
61  Generation::Name kind() { return Generation::MarkSweepCompact; }
62
63  // Printing
64  const char* name() const { return "tenured generation"; }
65  const char* short_name() const { return "Tenured"; }
66
67  // Does a "full" (forced) collection invoked on this generation collect
68  // all younger generations as well? Note that this is a
69  // hack to allow the collection of the younger gen first if the flag is
70  // set.
71  virtual bool full_collects_younger_generations() const {
72    return !ScavengeBeforeFullGC;
73  }
74
75  size_t unsafe_max_alloc_nogc() const;
76  size_t contiguous_available() const;
77
78  // Iteration
79  void object_iterate(ObjectClosure* blk);
80
81  virtual inline HeapWord* allocate(size_t word_size, bool is_tlab);
82  virtual inline HeapWord* par_allocate(size_t word_size, bool is_tlab);
83
84#define TenuredGen_SINCE_SAVE_MARKS_DECL(OopClosureType, nv_suffix)     \
85  void oop_since_save_marks_iterate##nv_suffix(OopClosureType* cl);
86  TenuredGen_SINCE_SAVE_MARKS_DECL(OopsInGenClosure,_v)
87  SPECIALIZED_SINCE_SAVE_MARKS_CLOSURES(TenuredGen_SINCE_SAVE_MARKS_DECL)
88
89  void save_marks();
90  void reset_saved_marks();
91  bool no_allocs_since_save_marks();
92
93  inline size_t block_size(const HeapWord* addr) const;
94
95  inline bool block_is_obj(const HeapWord* addr) const;
96
97  virtual void collect(bool full,
98                       bool clear_all_soft_refs,
99                       size_t size,
100                       bool is_tlab);
101  HeapWord* expand_and_allocate(size_t size,
102                                bool is_tlab,
103                                bool parallel = false);
104
105  virtual void prepare_for_verify();
106
107
108  virtual void gc_prologue(bool full);
109  virtual void gc_epilogue(bool full);
110  bool should_collect(bool   full,
111                      size_t word_size,
112                      bool   is_tlab);
113
114  virtual void compute_new_size();
115
116  // Performance Counter support
117  void update_counters();
118
119  virtual void record_spaces_top();
120
121  // Statistics
122
123  virtual void update_gc_stats(int level, bool full);
124
125  virtual bool promotion_attempt_is_safe(size_t max_promoted_in_bytes) const;
126
127  virtual void verify();
128  virtual void print_on(outputStream* st) const;
129};
130
131#endif // SHARE_VM_GC_SERIAL_TENUREDGENERATION_HPP
132