23 */ |
23 */ |
24 |
24 |
25 #ifndef SHARE_VM_CLASSFILE_STRINGTABLE_HPP |
25 #ifndef SHARE_VM_CLASSFILE_STRINGTABLE_HPP |
26 #define SHARE_VM_CLASSFILE_STRINGTABLE_HPP |
26 #define SHARE_VM_CLASSFILE_STRINGTABLE_HPP |
27 |
27 |
28 #include "utilities/hashtable.hpp" |
28 #include "gc/shared/oopStorage.hpp" |
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29 #include "gc/shared/oopStorageParState.hpp" |
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30 #include "memory/allocation.hpp" |
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31 #include "memory/padded.hpp" |
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32 #include "oops/oop.hpp" |
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33 #include "oops/weakHandle.hpp" |
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34 #include "utilities/concurrentHashTable.hpp" |
29 |
35 |
30 template <class T, class N> class CompactHashtable; |
36 template <class T, class N> class CompactHashtable; |
31 class CompactStringTableWriter; |
37 class CompactStringTableWriter; |
32 class FileMapInfo; |
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33 class SerializeClosure; |
38 class SerializeClosure; |
34 |
39 |
35 class StringTable : public RehashableHashtable<oop, mtSymbol> { |
40 class StringTable; |
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41 class StringTableConfig; |
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42 typedef ConcurrentHashTable<WeakHandle<vm_string_table_data>, |
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43 StringTableConfig, mtSymbol> StringTableHash; |
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44 |
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45 class StringTableCreateEntry; |
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46 |
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47 class StringTable : public CHeapObj<mtSymbol>{ |
36 friend class VMStructs; |
48 friend class VMStructs; |
37 friend class Symbol; |
49 friend class Symbol; |
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50 friend class StringTableConfig; |
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51 friend class StringTableCreateEntry; |
38 |
52 |
39 private: |
53 private: |
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54 void grow(JavaThread* jt); |
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55 void clean_dead_entries(JavaThread* jt); |
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56 |
40 // The string table |
57 // The string table |
41 static StringTable* _the_table; |
58 static StringTable* _the_table; |
42 |
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43 // Shared string table |
59 // Shared string table |
44 static CompactHashtable<oop, char> _shared_table; |
60 static CompactHashtable<oop, char> _shared_table; |
45 static bool _shared_string_mapped; |
61 static bool _shared_string_mapped; |
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62 static bool _alt_hash; |
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63 private: |
46 |
64 |
47 // Set if one bucket is out of balance due to hash algorithm deficiency |
65 // Set if one bucket is out of balance due to hash algorithm deficiency |
48 static bool _needs_rehashing; |
66 StringTableHash* _local_table; |
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67 size_t _current_size; |
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68 volatile bool _has_work; |
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69 volatile bool _needs_rehashing; |
49 |
70 |
50 // Claimed high water mark for parallel chunked scanning |
71 OopStorage* _weak_handles; |
51 static volatile int _parallel_claimed_idx; |
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52 |
72 |
53 static oop intern(Handle string_or_null, jchar* chars, int length, TRAPS); |
73 volatile size_t _items; |
54 oop basic_add(int index, Handle string_or_null, jchar* name, int len, |
74 DEFINE_PAD_MINUS_SIZE(1, DEFAULT_CACHE_LINE_SIZE, sizeof(volatile size_t)); |
55 unsigned int hashValue, TRAPS); |
75 volatile size_t _uncleaned_items; |
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76 DEFINE_PAD_MINUS_SIZE(2, DEFAULT_CACHE_LINE_SIZE, sizeof(volatile size_t)); |
56 |
77 |
57 oop lookup_in_main_table(int index, jchar* chars, int length, unsigned int hashValue); |
78 double get_load_factor(); |
58 static oop lookup_shared(jchar* name, int len, unsigned int hash); |
79 double get_dead_factor(); |
59 |
80 |
60 // Apply the give oop closure to the entries to the buckets |
81 void check_concurrent_work(); |
61 // in the range [start_idx, end_idx). |
82 void trigger_concurrent_work(); |
62 static void buckets_oops_do(OopClosure* f, int start_idx, int end_idx); |
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63 |
83 |
64 typedef StringTable::BucketUnlinkContext BucketUnlinkContext; |
84 static uintx item_added(); |
65 // Unlink or apply the give oop closure to the entries to the buckets |
85 static void item_removed(); |
66 // in the range [start_idx, end_idx). Unlinked bucket entries are collected in the given |
86 static size_t items_to_clean(size_t ncl); |
67 // context to be freed later. |
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68 // This allows multiple threads to work on the table at once. |
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69 static void buckets_unlink_or_oops_do(BoolObjectClosure* is_alive, OopClosure* f, int start_idx, int end_idx, BucketUnlinkContext* context); |
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70 |
87 |
71 // Hashing algorithm, used as the hash value used by the |
88 StringTable(); |
72 // StringTable for bucket selection and comparison (stored in the |
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73 // HashtableEntry structures). This is used in the String.intern() method. |
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74 static unsigned int hash_string(const jchar* s, int len); |
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75 static unsigned int hash_string(oop string); |
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76 static unsigned int alt_hash_string(const jchar* s, int len); |
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77 |
89 |
78 // Accessors for the string roots in the hashtable entries. |
90 static oop intern(Handle string_or_null_h, jchar* name, int len, TRAPS); |
79 // Use string_object_no_keepalive() only when the value is not returned |
91 oop do_intern(Handle string_or_null, jchar* name, int len, uintx hash, TRAPS); |
80 // outside of a scope where a thread transition is possible. |
92 oop do_lookup(jchar* name, int len, uintx hash); |
81 static oop string_object(HashtableEntry<oop, mtSymbol>* entry); |
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82 static oop string_object_no_keepalive(HashtableEntry<oop, mtSymbol>* entry); |
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83 static void set_string_object(HashtableEntry<oop, mtSymbol>* entry, oop string); |
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84 |
93 |
85 StringTable() : RehashableHashtable<oop, mtSymbol>((int)StringTableSize, |
94 void concurrent_work(JavaThread* jt); |
86 sizeof (HashtableEntry<oop, mtSymbol>)) {} |
95 void print_table_statistics(outputStream* st, const char* table_name); |
87 |
96 |
88 StringTable(HashtableBucket<mtSymbol>* t, int number_of_entries) |
97 void try_rehash_table(); |
89 : RehashableHashtable<oop, mtSymbol>((int)StringTableSize, sizeof (HashtableEntry<oop, mtSymbol>), t, |
98 bool do_rehash(); |
90 number_of_entries) {} |
99 |
91 public: |
100 public: |
92 // The string table |
101 // The string table |
93 static StringTable* the_table() { return _the_table; } |
102 static StringTable* the_table() { return _the_table; } |
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103 size_t table_size(Thread* thread = NULL); |
94 |
104 |
95 // Size of one bucket in the string table. Used when checking for rollover. |
105 static OopStorage* weak_storage() { return the_table()->_weak_handles; } |
96 static uint bucket_size() { return sizeof(HashtableBucket<mtSymbol>); } |
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97 |
106 |
98 static void create_table() { |
107 static void create_table() { |
99 assert(_the_table == NULL, "One string table allowed."); |
108 assert(_the_table == NULL, "One string table allowed."); |
100 _the_table = new StringTable(); |
109 _the_table = new StringTable(); |
101 } |
110 } |
102 |
111 |
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112 static void do_concurrent_work(JavaThread* jt); |
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113 static bool has_work() { return the_table()->_has_work; } |
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114 |
103 // GC support |
115 // GC support |
104 // Delete pointers to otherwise-unreachable objects. |
116 // Delete pointers to otherwise-unreachable objects. |
105 static void unlink_or_oops_do(BoolObjectClosure* cl, OopClosure* f) { |
117 static void unlink(BoolObjectClosure* cl) { |
106 int processed = 0; |
118 unlink_or_oops_do(cl); |
107 int removed = 0; |
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108 unlink_or_oops_do(cl, f, &processed, &removed); |
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109 } |
119 } |
110 static void unlink(BoolObjectClosure* cl) { |
120 static void unlink_or_oops_do(BoolObjectClosure* is_alive, OopClosure* f = NULL, |
111 int processed = 0; |
121 int* processed = NULL, int* removed = NULL); |
112 int removed = 0; |
122 |
113 unlink_or_oops_do(cl, NULL, &processed, &removed); |
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114 } |
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115 static void unlink_or_oops_do(BoolObjectClosure* cl, OopClosure* f, int* processed, int* removed); |
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116 static void unlink(BoolObjectClosure* cl, int* processed, int* removed) { |
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117 unlink_or_oops_do(cl, NULL, processed, removed); |
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118 } |
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119 // Serially invoke "f->do_oop" on the locations of all oops in the table. |
123 // Serially invoke "f->do_oop" on the locations of all oops in the table. |
120 static void oops_do(OopClosure* f); |
124 static void oops_do(OopClosure* f); |
121 |
125 |
122 // Possibly parallel versions of the above |
126 // Possibly parallel versions of the above |
123 static void possibly_parallel_unlink_or_oops_do(BoolObjectClosure* cl, OopClosure* f, int* processed, int* removed); |
127 static void possibly_parallel_unlink( |
124 static void possibly_parallel_unlink(BoolObjectClosure* cl, int* processed, int* removed) { |
128 OopStorage::ParState<false /* concurrent */, false /* const*/>* par_state_string, |
125 possibly_parallel_unlink_or_oops_do(cl, NULL, processed, removed); |
129 BoolObjectClosure* cl, int* processed, int* removed); |
126 } |
130 static void possibly_parallel_oops_do( |
127 static void possibly_parallel_oops_do(OopClosure* f); |
131 OopStorage::ParState<false /* concurrent */, false /* const*/>* par_state_string, |
128 |
132 OopClosure* f); |
129 // Internal test. |
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130 static void test_alt_hash() PRODUCT_RETURN; |
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131 |
133 |
132 // Probing |
134 // Probing |
133 static oop lookup(Symbol* symbol); |
135 static oop lookup(Symbol* symbol); |
134 static oop lookup(jchar* chars, int length); |
136 static oop lookup(jchar* chars, int length); |
135 |
137 |
136 // Interning |
138 // Interning |
137 static oop intern(Symbol* symbol, TRAPS); |
139 static oop intern(Symbol* symbol, TRAPS); |
138 static oop intern(oop string, TRAPS); |
140 static oop intern(oop string, TRAPS); |
139 static oop intern(const char *utf8_string, TRAPS); |
141 static oop intern(const char *utf8_string, TRAPS); |
140 |
142 |
141 // Debugging |
143 // Rehash the string table if it gets out of balance |
142 static void verify(); |
144 static void rehash_table(); |
143 static void dump(outputStream* st, bool verbose=false); |
145 static bool needs_rehashing() |
144 |
146 { return StringTable::the_table()->_needs_rehashing; } |
145 enum VerifyMesgModes { |
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146 _verify_quietly = 0, |
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147 _verify_with_mesgs = 1 |
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148 }; |
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149 |
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150 enum VerifyRetTypes { |
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151 _verify_pass = 0, |
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152 _verify_fail_continue = 1, |
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153 _verify_fail_done = 2 |
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154 }; |
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155 |
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156 static VerifyRetTypes compare_entries(int bkt1, int e_cnt1, |
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157 HashtableEntry<oop, mtSymbol>* e_ptr1, |
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158 int bkt2, int e_cnt2, |
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159 HashtableEntry<oop, mtSymbol>* e_ptr2); |
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160 static VerifyRetTypes verify_entry(int bkt, int e_cnt, |
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161 HashtableEntry<oop, mtSymbol>* e_ptr, |
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162 VerifyMesgModes mesg_mode); |
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163 static int verify_and_compare_entries(); |
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164 |
147 |
165 // Sharing |
148 // Sharing |
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149 private: |
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150 oop lookup_shared(jchar* name, int len, unsigned int hash) NOT_CDS_JAVA_HEAP_RETURN_(NULL); |
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151 static void copy_shared_string_table(CompactStringTableWriter* ch_table) NOT_CDS_JAVA_HEAP_RETURN; |
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152 public: |
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153 static oop create_archived_string(oop s, Thread* THREAD); |
166 static void set_shared_string_mapped() { _shared_string_mapped = true; } |
154 static void set_shared_string_mapped() { _shared_string_mapped = true; } |
167 static bool shared_string_mapped() { return _shared_string_mapped; } |
155 static bool shared_string_mapped() { return _shared_string_mapped; } |
168 static void shared_oops_do(OopClosure* f) NOT_CDS_JAVA_HEAP_RETURN; |
156 static void shared_oops_do(OopClosure* f) NOT_CDS_JAVA_HEAP_RETURN; |
169 static bool copy_shared_string(GrowableArray<MemRegion> *string_space, |
157 static void write_to_archive() NOT_CDS_JAVA_HEAP_RETURN; |
170 CompactStringTableWriter* ch_table) NOT_CDS_JAVA_HEAP_RETURN_(false); |
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171 static oop create_archived_string(oop s, Thread* THREAD) NOT_CDS_JAVA_HEAP_RETURN_(NULL); |
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172 static void write_to_archive(GrowableArray<MemRegion> *string_space) NOT_CDS_JAVA_HEAP_RETURN; |
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173 static void serialize(SerializeClosure* soc) NOT_CDS_JAVA_HEAP_RETURN; |
158 static void serialize(SerializeClosure* soc) NOT_CDS_JAVA_HEAP_RETURN; |
174 |
159 |
175 // Rehash the symbol table if it gets out of balance |
160 // Jcmd |
176 static void rehash_table(); |
161 static void dump(outputStream* st, bool verbose=false); |
177 static bool needs_rehashing() { return _needs_rehashing; } |
162 // Debugging |
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163 static size_t verify_and_compare_entries(); |
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164 static void verify(); |
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165 }; |
178 |
166 |
179 // Parallel chunked scanning |
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180 static void clear_parallel_claimed_index() { _parallel_claimed_idx = 0; } |
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181 static int parallel_claimed_index() { return _parallel_claimed_idx; } |
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182 }; |
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183 #endif // SHARE_VM_CLASSFILE_STRINGTABLE_HPP |
167 #endif // SHARE_VM_CLASSFILE_STRINGTABLE_HPP |