1 /*
 2  * Copyright (c) 2021, Red Hat, Inc. 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_SERVICES_HEAPOBJECTSTATISTICS_HPP
26 #define SHARE_SERVICES_HEAPOBJECTSTATISTICS_HPP
27 
28 #include "memory/allocation.hpp"
29 #include "oops/oopsHierarchy.hpp"
30 #include "runtime/task.hpp"
31 #include "runtime/vmOperation.hpp"
32 
33 class outputStream;
34 
35 class HeapObjectStatisticsTask : public PeriodicTask {
36 public:
37   HeapObjectStatisticsTask();
38   void task();
39 };
40 
41 class HeapObjectStatistics : public CHeapObj<mtGC> {
42 private:
43   static HeapObjectStatistics* _instance;
44 
45   HeapObjectStatisticsTask _task;
46   uint64_t _num_samples;
47   uint64_t _num_objects;
48   uint64_t _num_ihashed;
49   uint64_t _num_ihashed_moved;
50   uint64_t _num_locked;
51   uint64_t _lds;
52 
53   static void increase_counter(uint64_t& counter, uint64_t val = 1);
54 
55   void print(outputStream* out) const;
56 
57 public:
58   static void initialize();
59   static void shutdown();
60 
61   static HeapObjectStatistics* instance();
62 
63   HeapObjectStatistics();
64   void start();
65   void stop();
66 
67   void begin_sample();
68   void visit_object(oop object);
69 };
70 
71 #endif // SHARE_SERVICES_HEAPOBJECTSTATISTICS_HPP