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24 
25 #ifndef SHARE_UTILITIES_HASHTABLE_INLINE_HPP
26 #define SHARE_UTILITIES_HASHTABLE_INLINE_HPP
27 
28 #include "memory/allocation.inline.hpp"
29 #include "runtime/atomic.hpp"
30 #include "services/memTracker.hpp"
31 #include "utilities/hashtable.hpp"
32 #include "utilities/dtrace.hpp"
33 
34 // Inline function definitions for hashtable.hpp.
35 
36 // --------------------------------------------------------------------------
37 
38 // Initialize a table.
39 
BasicHashtable(int table_size,int entry_size)40 template <MEMFLAGS F> inline BasicHashtable<F>::BasicHashtable(int table_size, int entry_size) :
41     _entry_blocks(4) {
42   // Called on startup, no locking needed
43   initialize(table_size, entry_size, 0);
44   _buckets = NEW_C_HEAP_ARRAY2(HashtableBucket<F>, table_size, F, CURRENT_PC);
45   for (int index = 0; index < _table_size; index++) {
46     _buckets[index].clear();
47   }
48   _stats_rate = TableRateStatistics();
49 }
50 
51 
BasicHashtable(int table_size,int entry_size,HashtableBucket<F> * buckets,int number_of_entries)52 template <MEMFLAGS F> inline BasicHashtable<F>::BasicHashtable(int table_size, int entry_size,
53                                       HashtableBucket<F>* buckets,
54                                       int number_of_entries) :
55     _entry_blocks(4) {
56   // Called on startup, no locking needed
57   initialize(table_size, entry_size, number_of_entries);
58   _buckets = buckets;
59   _stats_rate = TableRateStatistics();
60 }
61 
~BasicHashtable()62 template <MEMFLAGS F> inline BasicHashtable<F>::~BasicHashtable() {
63   for (int i = 0; i < _entry_blocks.length(); i++) {
64     FREE_C_HEAP_ARRAY(char, _entry_blocks.at(i));
65   }
66   free_buckets();
67 }
68 
initialize(int table_size,int entry_size,int number_of_entries)69 template <MEMFLAGS F> inline void BasicHashtable<F>::initialize(int table_size, int entry_size,
70                                        int number_of_entries) {
71   // Called on startup, no locking needed
72   _table_size = table_size;
73   _entry_size = entry_size;
74   _free_list = NULL;
75   _first_free_entry = NULL;
76   _end_block = NULL;
77   _number_of_entries = number_of_entries;
78 }
79 
80 
81 // The following method is MT-safe and may be used with caution.
bucket(int i) const82 template <MEMFLAGS F> inline BasicHashtableEntry<F>* BasicHashtable<F>::bucket(int i) const {
83   return _buckets[i].get_entry();
84 }
85 
86 
set_entry(BasicHashtableEntry<F> * l)87 template <MEMFLAGS F> inline void HashtableBucket<F>::set_entry(BasicHashtableEntry<F>* l) {
88   // Warning: Preserve store ordering.  The PackageEntryTable, ModuleEntryTable and
89   //          SystemDictionary are read without locks.  The new entry must be
90   //          complete before other threads can be allowed to see it
91   //          via a store to _buckets[index].
92   Atomic::release_store(&_entry, l);
93 }
94 
95 
get_entry() const96 template <MEMFLAGS F> inline BasicHashtableEntry<F>* HashtableBucket<F>::get_entry() const {
97   // Warning: Preserve load ordering.  The PackageEntryTable, ModuleEntryTable and
98   //          SystemDictionary are read without locks.  The new entry must be
99   //          complete before other threads can be allowed to see it
100   //          via a store to _buckets[index].
101   return Atomic::load_acquire(&_entry);
102 }
103 
104 
set_entry(int index,BasicHashtableEntry<F> * entry)105 template <MEMFLAGS F> inline void BasicHashtable<F>::set_entry(int index, BasicHashtableEntry<F>* entry) {
106   _buckets[index].set_entry(entry);
107   if (entry != NULL) {
108     JFR_ONLY(_stats_rate.add();)
109   } else {
110     JFR_ONLY(_stats_rate.remove();)
111   }
112 }
113 
114 
add_entry(int index,BasicHashtableEntry<F> * entry)115 template <MEMFLAGS F> inline void BasicHashtable<F>::add_entry(int index, BasicHashtableEntry<F>* entry) {
116   entry->set_next(bucket(index));
117   _buckets[index].set_entry(entry);
118   ++_number_of_entries;
119   JFR_ONLY(_stats_rate.add();)
120 }
121 
free_entry(BasicHashtableEntry<F> * entry)122 template <MEMFLAGS F> inline void BasicHashtable<F>::free_entry(BasicHashtableEntry<F>* entry) {
123   entry->set_next(_free_list);
124   _free_list = entry;
125   --_number_of_entries;
126   JFR_ONLY(_stats_rate.remove();)
127 }
128 
129 #endif // SHARE_UTILITIES_HASHTABLE_INLINE_HPP
130