1 /*
2 * Copyright (c) 2002, 2013, 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_MEMORY_HEAPINSPECTION_HPP
26 #define SHARE_VM_MEMORY_HEAPINSPECTION_HPP
27
28 #include "memory/allocation.inline.hpp"
29 #include "oops/oop.inline.hpp"
30
31
32 // HeapInspection
33
34 // KlassInfoTable is a bucket hash table that
35 // maps klassOops to extra information:
36 // instance count and instance word size.
37 //
38 // A KlassInfoBucket is the head of a link list
39 // of KlassInfoEntry's
40 //
41 // KlassInfoHisto is a growable array of pointers
42 // to KlassInfoEntry's and is used to sort
43 // the entries.
44
45 class KlassInfoEntry: public CHeapObj<mtInternal> {
46 private:
47 KlassInfoEntry* _next;
48 klassOop _klass;
49 long _instance_count;
50 size_t _instance_words;
51
52 public:
53 KlassInfoEntry(klassOop k, KlassInfoEntry* next) :
54 _klass(k), _instance_count(0), _instance_words(0), _next(next)
55 {}
56 KlassInfoEntry* next() { return _next; }
57 bool is_equal(klassOop k) { return k == _klass; }
58 klassOop klass() { return _klass; }
59 long count() { return _instance_count; }
60 void set_count(long ct) { _instance_count = ct; }
61 size_t words() { return _instance_words; }
62 void set_words(size_t wds) { _instance_words = wds; }
63 int compare(KlassInfoEntry* e1, KlassInfoEntry* e2);
64 void print_on(outputStream* st) const;
65 };
66
67 class KlassInfoClosure: public StackObj {
68 public:
69 // Called for each KlassInfoEntry.
70 virtual void do_cinfo(KlassInfoEntry* cie) = 0;
71 };
72
73 class KlassInfoBucket: public CHeapObj<mtInternal> {
74 private:
75 KlassInfoEntry* _list;
76 KlassInfoEntry* list() { return _list; }
77 void set_list(KlassInfoEntry* l) { _list = l; }
78 public:
79 KlassInfoEntry* lookup(const klassOop k);
80 void initialize() { _list = NULL; }
81 void empty();
82 void iterate(KlassInfoClosure* cic);
83 };
84
85 class KlassInfoTable: public StackObj {
86 private:
87 int _size;
88 static const int _num_buckets = 20011;
89
90 // An aligned reference address (typically the least
91 // address in the perm gen) used for hashing klass
92 // objects.
93 HeapWord* _ref;
94
95 KlassInfoBucket* _buckets;
96 uint hash(klassOop p);
97 KlassInfoEntry* lookup(const klassOop k);
98
99 public:
100 KlassInfoTable(HeapWord* ref);
101 ~KlassInfoTable();
102 bool record_instance(const oop obj);
103 void iterate(KlassInfoClosure* cic);
104 bool allocation_failed() { return _buckets == NULL; }
105 };
106
107 class KlassInfoHisto : public StackObj {
108 private:
109 GrowableArray<KlassInfoEntry*>* _elements;
110 GrowableArray<KlassInfoEntry*>* elements() const { return _elements; }
111 const char* _title;
112 const char* title() const { return _title; }
113 static int sort_helper(KlassInfoEntry** e1, KlassInfoEntry** e2);
114 void print_elements(outputStream* st) const;
115 static const int _histo_initial_size = 1000;
116 public:
117 KlassInfoHisto(const char* title);
118 ~KlassInfoHisto();
119 void add(KlassInfoEntry* cie);
120 void print_on(outputStream* st) const;
121 void sort();
122 };
123
124
125 class HeapInspection : public AllStatic {
126 public:
127 static void heap_inspection(outputStream* st, bool need_prologue);
128 static size_t instance_inspection(KlassInfoTable* cit,
129 KlassInfoClosure* cl,
130 bool need_prologue,
131 BoolObjectClosure* filter = NULL);
132 static HeapWord* start_of_perm_gen();
133 static void find_instances_at_safepoint(klassOop k, GrowableArray<oop>* result);
134 private:
135 static bool is_shared_heap();
136 static void prologue();
137 static void epilogue();
138 };
139
140 #endif // SHARE_VM_MEMORY_HEAPINSPECTION_HPP