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24 
25 #ifndef SHARE_GC_SERIAL_TENUREDGENERATION_HPP
26 #define SHARE_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 
39 class 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
space() const54   ContiguousSpace* space() const { return _the_space; }
55 
56   void assert_correct_size_change_locking();
57 
58  public:
59   TenuredGeneration(ReservedSpace rs,
60                     size_t initial_byte_size,
61                     size_t min_byte_size,
62                     size_t max_byte_size,
63                     CardTableRS* remset);
64 
kind()65   Generation::Name kind() { return Generation::MarkSweepCompact; }
66 
67   // Printing
name() const68   const char* name() const { return "tenured generation"; }
short_name() const69   const char* short_name() const { return "Tenured"; }
70 
71   size_t unsafe_max_alloc_nogc() const;
72   size_t contiguous_available() const;
73 
74   // Iteration
75   void object_iterate(ObjectClosure* blk);
76 
77   virtual inline HeapWord* allocate(size_t word_size, bool is_tlab);
78   virtual inline HeapWord* par_allocate(size_t word_size, bool is_tlab);
79 
80   template <typename OopClosureType>
81   void oop_since_save_marks_iterate(OopClosureType* cl);
82 
83   void save_marks();
84   void reset_saved_marks();
85   bool no_allocs_since_save_marks();
86 
87   inline size_t block_size(const HeapWord* addr) const;
88 
89   inline bool block_is_obj(const HeapWord* addr) const;
90 
91   virtual void collect(bool full,
92                        bool clear_all_soft_refs,
93                        size_t size,
94                        bool is_tlab);
95 
96   HeapWord* expand_and_allocate(size_t size,
97                                 bool is_tlab,
98                                 bool parallel = false);
99 
100   virtual void prepare_for_verify();
101 
102   virtual void gc_prologue(bool full);
103   virtual void gc_epilogue(bool full);
104 
105   bool should_collect(bool   full,
106                       size_t word_size,
107                       bool   is_tlab);
108 
109   virtual void compute_new_size();
110 
111   // Performance Counter support
112   void update_counters();
113 
114   virtual void record_spaces_top();
115 
116   // Statistics
117 
118   virtual void update_gc_stats(Generation* current_generation, bool full);
119 
120   virtual bool promotion_attempt_is_safe(size_t max_promoted_in_bytes) const;
121 
122   virtual void verify();
123   virtual void print_on(outputStream* st) const;
124 };
125 
126 #endif // SHARE_GC_SERIAL_TENUREDGENERATION_HPP
127