1 /*
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 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.
 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).
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15  * You should have received a copy of the GNU General Public License version
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24 
25 #ifndef SHARE_JFR_LEAKPROFILER_CHAINS_DFSCLOSURE_HPP
26 #define SHARE_JFR_LEAKPROFILER_CHAINS_DFSCLOSURE_HPP
27 
28 #include "jfr/leakprofiler/utilities/unifiedOopRef.hpp"
29 #include "memory/iterator.hpp"
30 
31 class BitSet;
32 class Edge;
33 class EdgeStore;
34 class EdgeQueue;
35 
36 // Class responsible for iterating the heap depth-first
37 class DFSClosure : public BasicOopIterateClosure {
38  private:
39   // max dfs depth should not exceed size of stack
40   static const size_t max_dfs_depth = 4000;
41   static UnifiedOopRef _reference_stack[max_dfs_depth];
42 
43   EdgeStore* _edge_store;
44   BitSet* _mark_bits;
45   const Edge*_start_edge;
46   size_t _max_depth;
47   size_t _depth;
48   bool _ignore_root_set;
49 
50   DFSClosure(EdgeStore* edge_store, BitSet* mark_bits, const Edge* start_edge);
51 
52   void add_chain();
53   void closure_impl(UnifiedOopRef reference, const oop pointee);
54 
55  public:
56   virtual ReferenceIterationMode reference_iteration_mode() { return DO_FIELDS_EXCEPT_REFERENT; }
57 
58   static void find_leaks_from_edge(EdgeStore* edge_store, BitSet* mark_bits, const Edge* start_edge);
59   static void find_leaks_from_root_set(EdgeStore* edge_store, BitSet* mark_bits);
60   void do_root(UnifiedOopRef ref);
61 
62   virtual void do_oop(oop* ref);
63   virtual void do_oop(narrowOop* ref);
64 };
65 
66 #endif // SHARE_JFR_LEAKPROFILER_CHAINS_DFSCLOSURE_HPP