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_BFSCLOSURE_HPP
26 #define SHARE_JFR_LEAKPROFILER_CHAINS_BFSCLOSURE_HPP
27
28 #include "jfr/leakprofiler/chains/jfrbitset.hpp"
29 #include "jfr/leakprofiler/utilities/unifiedOopRef.hpp"
30 #include "memory/iterator.hpp"
31
32 class Edge;
33 class EdgeStore;
34 class EdgeQueue;
35
36 // Class responsible for iterating the heap breadth-first
37 class BFSClosure : public BasicOopIterateClosure {
38 private:
39 EdgeQueue* _edge_queue;
40 EdgeStore* _edge_store;
41 JFRBitSet* _mark_bits;
42 const Edge* _current_parent;
43 mutable size_t _current_frontier_level;
44 mutable size_t _next_frontier_idx;
45 mutable size_t _prev_frontier_idx;
46 size_t _dfs_fallback_idx;
47 bool _use_dfs;
48
49 void log_completed_frontier() const;
50 void log_dfs_fallback() const;
51
52 bool is_complete() const;
53 void step_frontier() const;
54
55 void closure_impl(UnifiedOopRef reference, const oop pointee);
56 void add_chain(UnifiedOopRef reference, const oop pointee);
57 void dfs_fallback();
58
59 void iterate(const Edge* parent);
60 void process(UnifiedOopRef reference, const oop pointee);
61
62 void process_root_set();
63 void process_queue();
64
65 public:
66 virtual ReferenceIterationMode reference_iteration_mode() { return DO_FIELDS_EXCEPT_REFERENT; }
67
68 BFSClosure(EdgeQueue* edge_queue, EdgeStore* edge_store, JFRBitSet* mark_bits);
69 void process();
70 void do_root(UnifiedOopRef ref);
71
72 virtual void do_oop(oop* ref);
73 virtual void do_oop(narrowOop* ref);
74 };
75
76 #endif // SHARE_JFR_LEAKPROFILER_CHAINS_BFSCLOSURE_HPP