1/*
2 * Copyright (c) 2014, 2019, Oracle and/or its affiliates. All rights reserved.
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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7 * published by the Free Software Foundation.
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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_JFR_LEAKPROFILER_SAMPLING_OBJECTSAMPLER_HPP
26#define SHARE_JFR_LEAKPROFILER_SAMPLING_OBJECTSAMPLER_HPP
27
28#include "memory/allocation.hpp"
29#include "jfr/utilities/jfrTime.hpp"
30
31typedef u8 traceid;
32
33class BoolObjectClosure;
34class JfrStackTrace;
35class OopClosure;
36class ObjectSample;
37class ObjectSampler;
38class SampleList;
39class SamplePriorityQueue;
40class Thread;
41
42// Class reponsible for holding samples and
43// making sure the samples are evenly distributed as
44// new entries are added and removed.
45class ObjectSampler : public CHeapObj<mtTracing> {
46 friend class EventEmitter;
47 friend class JfrRecorderService;
48 friend class LeakProfiler;
49 friend class StartOperation;
50 friend class StopOperation;
51 friend class ObjectSampleCheckpoint;
52 friend class WriteObjectSampleStacktrace;
53 private:
54 SamplePriorityQueue* _priority_queue;
55 SampleList* _list;
56 JfrTicks _last_sweep;
57 size_t _total_allocated;
58 size_t _threshold;
59 size_t _size;
60 bool _dead_samples;
61
62 // Lifecycle
63 explicit ObjectSampler(size_t size);
64 ~ObjectSampler();
65 static bool create(size_t size);
66 static bool is_created();
67 static ObjectSampler* sampler();
68 static void destroy();
69
70 // For operations that require exclusive access (non-safepoint)
71 static ObjectSampler* acquire();
72 static void release();
73
74 // Stacktrace
75 static void fill_stacktrace(JfrStackTrace* stacktrace, JavaThread* thread);
76 traceid stacktrace_id(const JfrStackTrace* stacktrace, JavaThread* thread);
77
78 // Sampling
79 static void sample(HeapWord* object, size_t size, JavaThread* thread);
80 void add(HeapWord* object, size_t size, traceid thread_id, JfrStackTrace* stacktrace, JavaThread* thread);
81 void scavenge();
82 void remove_dead(ObjectSample* sample);
83
84 // Called by GC
85 static void oops_do(BoolObjectClosure* is_alive, OopClosure* f);
86
87 const ObjectSample* item_at(int index) const;
88 ObjectSample* item_at(int index);
89 int item_count() const;
90 const ObjectSample* first() const;
91 const ObjectSample* last() const;
92 const ObjectSample* last_resolved() const;
93 void set_last_resolved(const ObjectSample* sample);
94 const JfrTicks& last_sweep() const;
95};
96
97#endif // SHARE_JFR_LEAKPROFILER_SAMPLING_OBJECTSAMPLER_HPP
98