1 /*

     2  * Copyright (c) 2014, 2018, 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_VM_LEAKPROFILER_CHAINS_EDGESTORE_HPP

    26 #define SHARE_VM_LEAKPROFILER_CHAINS_EDGESTORE_HPP

    27 

    28 #include "jfr/utilities/jfrHashtable.hpp"

    29 #include "jfr/leakprofiler/chains/edge.hpp"

    30 #include "memory/allocation.hpp"

    31 

    32 typedef u8 traceid;

    33 

    34 class RoutableEdge : public Edge {

    35  private:

    36   mutable const RoutableEdge* _skip_edge;

    37   mutable size_t _skip_length;

    38   mutable bool _processed;

    39 

    40  public:

    41   RoutableEdge();

    42   RoutableEdge(const Edge* parent, const oop* reference);

    43   RoutableEdge(const Edge& edge);

    44   RoutableEdge(const RoutableEdge& edge);

    45   void operator=(const RoutableEdge& edge);

    46 

    47   const RoutableEdge* skip_edge() const { return _skip_edge; }

    48   size_t skip_length() const { return _skip_length; }

    49 

    50   bool is_skip_edge() const { return _skip_edge != NULL; }

    51   bool processed() const { return _processed; }

    52   bool is_sentinel() const {

    53     return _skip_edge == NULL && _skip_length == 1;

    54   }

    55 

    56   void set_skip_edge(const RoutableEdge* edge) const {

    57     assert(!is_skip_edge(), "invariant");

    58     assert(edge != this, "invariant");

    59     _skip_edge = edge;

    60   }

    61 

    62   void set_skip_length(size_t length) const {

    63     _skip_length = length;

    64   }

    65 

    66   void set_processed() const {

    67     assert(!_processed, "invariant");

    68     _processed = true;

    69   }

    70 

    71   // true navigation according to physical tree representation

    72   const RoutableEdge* physical_parent() const {

    73     return static_cast<const RoutableEdge*>(parent());

    74   }

    75 

    76   // logical navigation taking skip levels into account

    77   const RoutableEdge* logical_parent() const {

    78     return is_skip_edge() ? skip_edge() : physical_parent();

    79   }

    80 

    81   size_t logical_distance_to_root() const;

    82 };

    83 

    84 class EdgeStore : public CHeapObj<mtTracing> {

    85   typedef HashTableHost<RoutableEdge, traceid, Entry, EdgeStore> EdgeHashTable;

    86   typedef EdgeHashTable::HashEntry EdgeEntry;

    87   template <typename,

    88             typename,

    89             template<typename, typename> class,

    90             typename,

    91             size_t>

    92   friend class HashTableHost;

    93  private:

    94   static traceid _edge_id_counter;

    95   EdgeHashTable* _edges;

    96 

    97   // Hash table callbacks

    98   void assign_id(EdgeEntry* entry);

    99   bool equals(const Edge& query, uintptr_t hash, const EdgeEntry* entry);

   100 

   101   const Edge* get_edge(const Edge* edge) const;

   102   const Edge* put(const Edge* edge);

   103 

   104  public:

   105   EdgeStore();

   106   ~EdgeStore();

   107 

   108   void add_chain(const Edge* chain, size_t length);

   109   bool is_empty() const;

   110   size_t number_of_entries() const;

   111 

   112   traceid get_id(const Edge* edge) const;

   113   traceid get_root_id(const Edge* edge) const;

   114 

   115   template <typename T>

   116   void iterate_edges(T& functor) const { _edges->iterate_value<T>(functor); }

   117 };

   118 

   119 #endif // SHARE_VM_LEAKPROFILER_CHAINS_EDGESTORE_HPP