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.
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_JFR_LEAKPROFILER_CHAINS_EDGESTORE_HPP
26 #define SHARE_JFR_LEAKPROFILER_CHAINS_EDGESTORE_HPP
27
28 #include "jfr/leakprofiler/chains/edge.hpp"
29 #include "jfr/leakprofiler/utilities/unifiedOopRef.hpp"
30 #include "jfr/utilities/jfrHashtable.hpp"
31 #include "memory/allocation.hpp"
32
33 typedef u8 traceid;
34
35 class StoredEdge : public Edge {
36 private:
37 mutable traceid _gc_root_id;
38 size_t _skip_length;
39
40 public:
41 StoredEdge();
42 StoredEdge(const Edge* parent, UnifiedOopRef reference);
43 StoredEdge(const Edge& edge);
44 StoredEdge(const StoredEdge& edge);
45
46 traceid gc_root_id() const { return _gc_root_id; }
47 void set_gc_root_id(traceid root_id) const { _gc_root_id = root_id; }
48
49 bool is_skip_edge() const { return _skip_length != 0; }
50 size_t skip_length() const { return _skip_length; }
51 void set_skip_length(size_t length) { _skip_length = length; }
52
53 void set_parent(const Edge* edge) { this->_parent = edge; }
54
55 StoredEdge* parent() const {
56 return const_cast<StoredEdge*>(static_cast<const StoredEdge*>(Edge::parent()));
57 }
58 };
59
60 class EdgeStore : public CHeapObj<mtTracing> {
61 typedef HashTableHost<StoredEdge, traceid, JfrHashtableEntry, EdgeStore> EdgeHashTable;
62 typedef EdgeHashTable::HashEntry EdgeEntry;
63 template <typename,
64 typename,
65 template<typename, typename> class,
66 typename,
67 size_t>
68 friend class HashTableHost;
69 friend class EventEmitter;
70 friend class ObjectSampleWriter;
71 friend class ObjectSampleCheckpoint;
72 private:
73 static traceid _edge_id_counter;
74 EdgeHashTable* _edges;
75
76 // Hash table callbacks
77 void on_link(EdgeEntry* entry);
78 bool on_equals(uintptr_t hash, const EdgeEntry* entry);
79 void on_unlink(EdgeEntry* entry);
80
81 StoredEdge* get(UnifiedOopRef reference) const;
82 StoredEdge* put(UnifiedOopRef reference);
83 traceid gc_root_id(const Edge* edge) const;
84
85 bool put_edges(StoredEdge** previous, const Edge** current, size_t length);
86 bool put_skip_edge(StoredEdge** previous, const Edge** current, size_t distance_to_root);
87 void put_chain_epilogue(StoredEdge* leak_context_edge, const Edge* root) const;
88
89 StoredEdge* associate_leak_context_with_candidate(const Edge* edge);
90 void store_gc_root_id_in_leak_context_edge(StoredEdge* leak_context_edge, const Edge* root) const;
91 StoredEdge* link_new_edge(StoredEdge** previous, const Edge** current);
92 void link_with_existing_chain(const StoredEdge* current_stored, StoredEdge** previous, size_t previous_length);
93
94 template <typename T>
95 void iterate(T& functor) const { _edges->iterate_value<T>(functor); }
96
97 DEBUG_ONLY(bool contains(UnifiedOopRef reference) const;)
98
99 public:
100 EdgeStore();
101 ~EdgeStore();
102
103 bool is_empty() const;
104 traceid get_id(const Edge* edge) const;
105 void put_chain(const Edge* chain, size_t length);
106 };
107
108 #endif // SHARE_JFR_LEAKPROFILER_CHAINS_EDGESTORE_HPP