1 /*
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3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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5  * This code is free software; you can redistribute it and/or modify it
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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).
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24 
25 #ifndef SHARE_MEMORY_HEAPSHARED_HPP
26 #define SHARE_MEMORY_HEAPSHARED_HPP
27 
28 #include "classfile/compactHashtable.hpp"
29 #include "classfile/systemDictionary.hpp"
30 #include "memory/allocation.hpp"
31 #include "memory/metaspaceShared.hpp"
32 #include "oops/compressedOops.hpp"
33 #include "oops/objArrayKlass.hpp"
34 #include "oops/oop.hpp"
35 #include "oops/typeArrayKlass.hpp"
36 #include "utilities/bitMap.hpp"
37 #include "utilities/growableArray.hpp"
38 #include "utilities/resourceHash.hpp"
39 
40 #if INCLUDE_CDS_JAVA_HEAP
41 struct ArchivableStaticFieldInfo {
42   const char* klass_name;
43   const char* field_name;
44   InstanceKlass* klass;
45   int offset;
46   BasicType type;
47 };
48 
49 // A dump time sub-graph info for Klass _k. It includes the entry points
50 // (static fields in _k's mirror) of the archived sub-graphs reachable
51 // from _k's mirror. It also contains a list of Klasses of the objects
52 // within the sub-graphs.
53 class KlassSubGraphInfo: public CHeapObj<mtClass> {
54  private:
55   // The class that contains the static field(s) as the entry point(s)
56   // of archived object sub-graph(s).
57   Klass* _k;
58   // A list of classes need to be loaded and initialized before the archived
59   // object sub-graphs can be accessed at runtime.
60   GrowableArray<Klass*>* _subgraph_object_klasses;
61   // A list of _k's static fields as the entry points of archived sub-graphs.
62   // For each entry field, it is a tuple of field_offset, field_value and
63   // is_closed_archive flag.
64   GrowableArray<juint>*  _subgraph_entry_fields;
65 
66  public:
KlassSubGraphInfo(Klass * k)67   KlassSubGraphInfo(Klass* k) :
68     _k(k),  _subgraph_object_klasses(NULL),
69     _subgraph_entry_fields(NULL) {}
~KlassSubGraphInfo()70   ~KlassSubGraphInfo() {
71     if (_subgraph_object_klasses != NULL) {
72       delete _subgraph_object_klasses;
73     }
74     if (_subgraph_entry_fields != NULL) {
75       delete _subgraph_entry_fields;
76     }
77   };
78 
klass()79   Klass* klass()            { return _k; }
subgraph_object_klasses()80   GrowableArray<Klass*>* subgraph_object_klasses() {
81     return _subgraph_object_klasses;
82   }
subgraph_entry_fields()83   GrowableArray<juint>*  subgraph_entry_fields() {
84     return _subgraph_entry_fields;
85   }
86   void add_subgraph_entry_field(int static_field_offset, oop v,
87                                 bool is_closed_archive);
88   void add_subgraph_object_klass(Klass *orig_k, Klass *relocated_k);
num_subgraph_object_klasses()89   int num_subgraph_object_klasses() {
90     return _subgraph_object_klasses == NULL ? 0 :
91            _subgraph_object_klasses->length();
92   }
93 };
94 
95 // An archived record of object sub-graphs reachable from static
96 // fields within _k's mirror. The record is reloaded from the archive
97 // at runtime.
98 class ArchivedKlassSubGraphInfoRecord {
99  private:
100   Klass* _k;
101 
102   // contains pairs of field offset and value for each subgraph entry field
103   Array<juint>* _entry_field_records;
104 
105   // klasses of objects in archived sub-graphs referenced from the entry points
106   // (static fields) in the containing class
107   Array<Klass*>* _subgraph_object_klasses;
108  public:
ArchivedKlassSubGraphInfoRecord()109   ArchivedKlassSubGraphInfoRecord() :
110     _k(NULL), _entry_field_records(NULL), _subgraph_object_klasses(NULL) {}
111   void init(KlassSubGraphInfo* info);
klass() const112   Klass* klass() const { return _k; }
entry_field_records() const113   Array<juint>*  entry_field_records() const { return _entry_field_records; }
subgraph_object_klasses() const114   Array<Klass*>* subgraph_object_klasses() const { return _subgraph_object_klasses; }
115 };
116 #endif // INCLUDE_CDS_JAVA_HEAP
117 
118 class HeapShared: AllStatic {
119   friend class VerifySharedOopClosure;
120  private:
121 
122 #if INCLUDE_CDS_JAVA_HEAP
123   static bool _closed_archive_heap_region_mapped;
124   static bool _open_archive_heap_region_mapped;
125   static bool _archive_heap_region_fixed;
126 
oop_equals(oop const & p1,oop const & p2)127   static bool oop_equals(oop const& p1, oop const& p2) {
128     return oopDesc::equals(p1, p2);
129   }
130   static unsigned oop_hash(oop const& p);
131 
132   typedef ResourceHashtable<oop, oop,
133       HeapShared::oop_hash,
134       HeapShared::oop_equals,
135       15889, // prime number
136       ResourceObj::C_HEAP> ArchivedObjectCache;
137   static ArchivedObjectCache* _archived_object_cache;
138 
klass_equals(Klass * const & p1,Klass * const & p2)139   static bool klass_equals(Klass* const& p1, Klass* const& p2) {
140     return primitive_equals<Klass*>(p1, p2);
141   }
142 
klass_hash(Klass * const & klass)143   static unsigned klass_hash(Klass* const& klass) {
144     return primitive_hash<address>((address)klass);
145   }
146 
147   class DumpTimeKlassSubGraphInfoTable
148     : public ResourceHashtable<Klass*, KlassSubGraphInfo,
149                                HeapShared::klass_hash,
150                                HeapShared::klass_equals,
151                                137, // prime number
152                                ResourceObj::C_HEAP> {
153   public:
154     int _count;
155   };
156 
157 public: // solaris compiler wants this for RunTimeKlassSubGraphInfoTable
record_equals_compact_hashtable_entry(const ArchivedKlassSubGraphInfoRecord * value,const Klass * key,int len_unused)158   inline static bool record_equals_compact_hashtable_entry(
159        const ArchivedKlassSubGraphInfoRecord* value, const Klass* key, int len_unused) {
160     return (value->klass() == key);
161   }
162 
163 private:
164   typedef OffsetCompactHashtable<
165     const Klass*,
166     const ArchivedKlassSubGraphInfoRecord*,
167     record_equals_compact_hashtable_entry
168     > RunTimeKlassSubGraphInfoTable;
169 
170   static DumpTimeKlassSubGraphInfoTable* _dump_time_subgraph_info_table;
171   static RunTimeKlassSubGraphInfoTable _run_time_subgraph_info_table;
172 
173   static void check_closed_archive_heap_region_object(InstanceKlass* k,
174                                                       Thread* THREAD);
175 
176   static void archive_object_subgraphs(ArchivableStaticFieldInfo fields[],
177                                        int num,
178                                        bool is_closed_archive,
179                                        Thread* THREAD);
180 
181   // Archive object sub-graph starting from the given static field
182   // in Klass k's mirror.
183   static void archive_reachable_objects_from_static_field(
184     InstanceKlass* k, const char* klass_name,
185     int field_offset, const char* field_name,
186     bool is_closed_archive, TRAPS);
187 
188   static void verify_subgraph_from_static_field(
189     InstanceKlass* k, int field_offset) PRODUCT_RETURN;
190   static void verify_reachable_objects_from(oop obj, bool is_archived) PRODUCT_RETURN;
191   static void verify_subgraph_from(oop orig_obj) PRODUCT_RETURN;
192 
193   static KlassSubGraphInfo* get_subgraph_info(Klass *k);
194 
195   static void init_subgraph_entry_fields(ArchivableStaticFieldInfo fields[],
196                                          int num, Thread* THREAD);
197 
198   // Used by decode_from_archive
199   static address _narrow_oop_base;
200   static int     _narrow_oop_shift;
201 
202   typedef ResourceHashtable<oop, bool,
203       HeapShared::oop_hash,
204       HeapShared::oop_equals,
205       15889, // prime number
206       ResourceObj::C_HEAP> SeenObjectsTable;
207 
208   static SeenObjectsTable *_seen_objects_table;
209 
init_seen_objects_table()210   static void init_seen_objects_table() {
211     assert(_seen_objects_table == NULL, "must be");
212     _seen_objects_table = new (ResourceObj::C_HEAP, mtClass)SeenObjectsTable();
213   }
delete_seen_objects_table()214   static void delete_seen_objects_table() {
215     assert(_seen_objects_table != NULL, "must be");
216     delete _seen_objects_table;
217     _seen_objects_table = NULL;
218   }
219 
220   // Statistics (for one round of start_recording_subgraph ... done_recording_subgraph)
221   static int _num_new_walked_objs;
222   static int _num_new_archived_objs;
223   static int _num_old_recorded_klasses;
224 
225   // Statistics (for all archived subgraphs)
226   static int _num_total_subgraph_recordings;
227   static int _num_total_walked_objs;
228   static int _num_total_archived_objs;
229   static int _num_total_recorded_klasses;
230   static int _num_total_verifications;
231 
232   static void start_recording_subgraph(InstanceKlass *k, const char* klass_name);
233   static void done_recording_subgraph(InstanceKlass *k, const char* klass_name);
234 
235   static bool has_been_seen_during_subgraph_recording(oop obj);
236   static void set_has_been_seen_during_subgraph_recording(oop obj);
237 
238  public:
create_archived_object_cache()239   static void create_archived_object_cache() {
240     _archived_object_cache =
241       new (ResourceObj::C_HEAP, mtClass)ArchivedObjectCache();
242   }
destroy_archived_object_cache()243   static void destroy_archived_object_cache() {
244     delete _archived_object_cache;
245     _archived_object_cache = NULL;
246   }
archived_object_cache()247   static ArchivedObjectCache* archived_object_cache() {
248     return _archived_object_cache;
249   }
250 
251   static oop find_archived_heap_object(oop obj);
252   static oop archive_heap_object(oop obj, Thread* THREAD);
253   static oop materialize_archived_object(narrowOop v);
254 
255   static void archive_klass_objects(Thread* THREAD);
256 
set_archive_heap_region_fixed()257   static void set_archive_heap_region_fixed() {
258     _archive_heap_region_fixed = true;
259   }
archive_heap_region_fixed()260   static bool archive_heap_region_fixed() {
261     return _archive_heap_region_fixed;
262   }
263 
264   static void archive_java_heap_objects(GrowableArray<MemRegion> *closed,
265                                         GrowableArray<MemRegion> *open);
266   static void copy_closed_archive_heap_objects(GrowableArray<MemRegion> * closed_archive);
267   static void copy_open_archive_heap_objects(GrowableArray<MemRegion> * open_archive);
268 
269   static oop archive_reachable_objects_from(int level,
270                                             KlassSubGraphInfo* subgraph_info,
271                                             oop orig_obj,
272                                             bool is_closed_archive,
273                                             TRAPS);
274 
275   static ResourceBitMap calculate_oopmap(MemRegion region);
276 #endif // INCLUDE_CDS_JAVA_HEAP
277 
278  public:
is_heap_object_archiving_allowed()279   static bool is_heap_object_archiving_allowed() {
280     CDS_JAVA_HEAP_ONLY(return (UseG1GC && UseCompressedOops && UseCompressedClassPointers);)
281     NOT_CDS_JAVA_HEAP(return false;)
282   }
283 
is_heap_region(int idx)284   static bool is_heap_region(int idx) {
285     CDS_JAVA_HEAP_ONLY(return (idx >= MetaspaceShared::first_closed_archive_heap_region &&
286                                idx <= MetaspaceShared::last_open_archive_heap_region));
287     NOT_CDS_JAVA_HEAP_RETURN_(false);
288   }
289 
set_closed_archive_heap_region_mapped()290   static void set_closed_archive_heap_region_mapped() {
291     CDS_JAVA_HEAP_ONLY(_closed_archive_heap_region_mapped = true);
292     NOT_CDS_JAVA_HEAP_RETURN;
293   }
closed_archive_heap_region_mapped()294   static bool closed_archive_heap_region_mapped() {
295     CDS_JAVA_HEAP_ONLY(return _closed_archive_heap_region_mapped);
296     NOT_CDS_JAVA_HEAP_RETURN_(false);
297   }
set_open_archive_heap_region_mapped()298   static void set_open_archive_heap_region_mapped() {
299     CDS_JAVA_HEAP_ONLY(_open_archive_heap_region_mapped = true);
300     NOT_CDS_JAVA_HEAP_RETURN;
301   }
open_archive_heap_region_mapped()302   static bool open_archive_heap_region_mapped() {
303     CDS_JAVA_HEAP_ONLY(return _open_archive_heap_region_mapped);
304     NOT_CDS_JAVA_HEAP_RETURN_(false);
305   }
306 
307   static void fixup_mapped_heap_regions() NOT_CDS_JAVA_HEAP_RETURN;
308 
309   inline static bool is_archived_object(oop p) NOT_CDS_JAVA_HEAP_RETURN_(false);
310 
311   static void initialize_from_archived_subgraph(Klass* k) NOT_CDS_JAVA_HEAP_RETURN;
312 
313   // NarrowOops stored in the CDS archive may use a different encoding scheme
314   // than CompressedOops::{base,shift} -- see FileMapInfo::map_heap_regions_impl.
315   // To decode them, do not use CompressedOops::decode_not_null. Use this
316   // function instead.
317   inline static oop decode_from_archive(narrowOop v) NOT_CDS_JAVA_HEAP_RETURN_(NULL);
318 
319   static void init_narrow_oop_decoding(address base, int shift) NOT_CDS_JAVA_HEAP_RETURN;
320 
321   static void patch_archived_heap_embedded_pointers(MemRegion mem, address  oopmap,
322                                                     size_t oopmap_in_bits) NOT_CDS_JAVA_HEAP_RETURN;
323 
324   static void init_subgraph_entry_fields(Thread* THREAD) NOT_CDS_JAVA_HEAP_RETURN;
325   static void write_subgraph_info_table() NOT_CDS_JAVA_HEAP_RETURN;
326   static void serialize_subgraph_info_table_header(SerializeClosure* soc) NOT_CDS_JAVA_HEAP_RETURN;
327 };
328 #endif // SHARE_MEMORY_HEAPSHARED_HPP
329