1 /*
2 * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
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).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #ifndef SHARE_VM_PRIMS_JVMTITAGMAP_HPP
26 #define SHARE_VM_PRIMS_JVMTITAGMAP_HPP
27
28 #ifndef KERNEL
29 #include "gc_interface/collectedHeap.hpp"
30 #include "jvmtifiles/jvmti.h"
31 #include "jvmtifiles/jvmtiEnv.hpp"
32 #include "memory/allocation.hpp"
33 #include "memory/genCollectedHeap.hpp"
34 #include "memory/universe.hpp"
35 #endif
36
37 // JvmtiTagMap
38
39 #ifndef _JAVA_JVMTI_TAG_MAP_H_
40 #define _JAVA_JVMTI_TAG_MAP_H_
41
42 // forward references
43 class JvmtiTagHashmap;
44 class JvmtiTagHashmapEntry;
45 class JvmtiTagHashmapEntryClosure;
46
47 class JvmtiTagMap : public CHeapObj {
48 private:
49
50 enum{
51 n_hashmaps = 2, // encapsulates 2 hashmaps
52 max_free_entries = 4096 // maximum number of free entries per env
53 };
54
55 // memory region for young generation
56 static MemRegion _young_gen;
57 static void get_young_generation();
58
59 JvmtiEnv* _env; // the jvmti environment
60 Mutex _lock; // lock for this tag map
61 JvmtiTagHashmap* _hashmap[n_hashmaps]; // the hashmaps
62
63 JvmtiTagHashmapEntry* _free_entries; // free list for this environment
64 int _free_entries_count; // number of entries on the free list
65
66 // create a tag map
67 JvmtiTagMap(JvmtiEnv* env);
68
69 // accessors
70 inline Mutex* lock() { return &_lock; }
71 inline JvmtiEnv* env() const { return _env; }
72
73 // rehash tags maps for generation start to end
74 void rehash(int start, int end);
75
76 // indicates if the object is in the young generation
77 static bool is_in_young(oop o);
78
79 // iterate over all entries in this tag map
80 void entry_iterate(JvmtiTagHashmapEntryClosure* closure);
81
82 public:
83
84 // indicates if this tag map is locked
85 bool is_locked() { return lock()->is_locked(); }
86
87 // return the appropriate hashmap for a given object
88 JvmtiTagHashmap* hashmap_for(oop o);
89
90 // create/destroy entries
91 JvmtiTagHashmapEntry* create_entry(jweak ref, jlong tag);
92 void destroy_entry(JvmtiTagHashmapEntry* entry);
93
94 // returns true if the hashmaps are empty
95 bool is_empty();
96
97 // return tag for the given environment
98 static JvmtiTagMap* tag_map_for(JvmtiEnv* env);
99
100 // destroy tag map
101 ~JvmtiTagMap();
102
103 // set/get tag
104 void set_tag(jobject obj, jlong tag);
105 jlong get_tag(jobject obj);
106
107 // deprecated heap iteration functions
108 void iterate_over_heap(jvmtiHeapObjectFilter object_filter,
109 KlassHandle klass,
110 jvmtiHeapObjectCallback heap_object_callback,
111 const void* user_data);
112
113 void iterate_over_reachable_objects(jvmtiHeapRootCallback heap_root_callback,
114 jvmtiStackReferenceCallback stack_ref_callback,
115 jvmtiObjectReferenceCallback object_ref_callback,
116 const void* user_data);
117
118 void iterate_over_objects_reachable_from_object(jobject object,
119 jvmtiObjectReferenceCallback object_reference_callback,
120 const void* user_data);
121
122
123 // advanced (JVMTI 1.1) heap iteration functions
124 void iterate_through_heap(jint heap_filter,
125 KlassHandle klass,
126 const jvmtiHeapCallbacks* callbacks,
127 const void* user_data);
128
129 void follow_references(jint heap_filter,
130 KlassHandle klass,
131 jobject initial_object,
132 const jvmtiHeapCallbacks* callbacks,
133 const void* user_data);
134
135 // get tagged objects
136 jvmtiError get_objects_with_tags(const jlong* tags, jint count,
137 jint* count_ptr, jobject** object_result_ptr,
138 jlong** tag_result_ptr);
139
140 // call post-GC to rehash the tag maps.
141 static void gc_epilogue(bool full);
142
143 // call after referencing processing has completed (CMS)
144 static void cms_ref_processing_epilogue();
145 };
146
147 #endif /* _JAVA_JVMTI_TAG_MAP_H_ */
148
149 #endif // SHARE_VM_PRIMS_JVMTITAGMAP_HPP