src/base/stats/group.hh

   1 /*
   2  * Copyright (c) 2019 Arm Limited
   3  * All rights reserved
   4  *
   5  * The license below extends only to copyright in the software and shall
   6  * not be construed as granting a license to any other intellectual
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   8  * to a hardware implementation of the functionality of the software
   9  * licensed hereunder.  You may use the software subject to the license
  10  * terms below provided that you ensure that this notice is replicated
  11  * unmodified and in its entirety in all distributions of the software,
  12  * modified or unmodified, in source code or in binary form.
  13  *
  14  * Redistribution and use in source and binary forms, with or without
  15  * modification, are permitted provided that the following conditions are
  16  * met: redistributions of source code must retain the above copyright
  17  * notice, this list of conditions and the following disclaimer;
  18  * redistributions in binary form must reproduce the above copyright
  19  * notice, this list of conditions and the following disclaimer in the
  20  * documentation and/or other materials provided with the distribution;
  21  * neither the name of the copyright holders nor the names of its
  22  * contributors may be used to endorse or promote products derived from
  23  * this software without specific prior written permission.
  24  *
  25  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  26  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  27  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  28  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  29  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  30  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  31  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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  35  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  36  *
  37  * Authors: Andreas Sandberg
  38  */
  39
  40 #ifndef __BASE_STATS_GROUP_HH__
  41 #define __BASE_STATS_GROUP_HH__
  42
  43 #include <map>
  44 #include <vector>
  45 #include <string>
  46
  47 /**
  48  * Convenience macro to add a stat to a statistics group.
  49  *
  50  * This macro is used to add a stat to a Stats::Group in the
  51  * initilization list in the Group's constructor. The macro
  52  * automatically assigns the stat to the current group and gives it
  53  * the same name as in the class. For example:
  54  *
  55  * \code
  56  * struct MyStats : public Stats::Group
  57  * {
  58  *     Stats::Scalar scalar0;
  59  *     Stats::Scalar scalar1;
  60  *
  61  *     Group()
  62  *         : ADD_STAT(scalar0, "Description of scalar0"),
  63  *           scalar1(this, "scalar1", "Description of scalar1")
  64  *     {
  65  *     }
  66  * };
  67  * \endcode
  68  */
  69 #define ADD_STAT(n, ...) n(this, # n, __VA_ARGS__)
  70
  71 namespace Stats {
  72
  73 class Info;
  74
  75 /**
  76  * Statistics container.
  77  *
  78  * A stat group is a hierarchical structure that contain statistics
  79  * and other groups. Groups are used by the stat system to reflect
  80  * gem5's SimObject hierarchy and to expose internal hierarchy within
  81  * an object. They can also be used to conveniently group stats into
  82  * their own class/struct and then be merged into the parent group
  83  * (typically a SimObject).
  84  */
  85 class Group
  86 {
  87   public:
  88     Group() = delete;
  89     Group(const Group &) = delete;
  90     Group &operator=(const Group &) = delete;
  91
  92     /**
  93      * Construct a new statistics group.
  94      *
  95      * The constructor takes two parameters, a parent and a name. The
  96      * parent group should typically be specified. However, there are
  97      * special cases where the parent group may be null. One such
  98      * special case is SimObjects where the Python code performs late
  99      * binding of the group parent.
 100      *
 101      * If the name parameter is NULL, the group gets merged into the
 102      * parent group instead of creating a sub-group. Stats belonging
 103      * to a merged group behave as if they have been added directly to
 104      * the parent group.
 105      *
 106      * @param parent Parent group to associate this object to.
 107      * @param name Name of this group, can be NULL to merge this group
 108      * with the parent group.
 109      */
 110     Group(Group *parent, const char *name = nullptr);
 111
 112     virtual ~Group();
 113
 114     /**
 115      * Callback to set stat parameters.
 116      *
 117      * This callback is typically used for complex stats (e.g.,
 118      * distributions) that need parameters in addition to a name and a
 119      * description. Stat names and descriptions should typically be
 120      * set from the constructor usingo from the constructor using the
 121      * ADD_STAT macro.
 122      */
 123     virtual void regStats();
 124
 125     /**
 126      * Callback to reset stats.
 127      */
 128     virtual void resetStats();
 129
 130     /**
 131      * Register a stat with this group. This method is normally called
 132      * automatically when a stat is instantiated.
 133      */
 134     void addStat(Stats::Info *info);
 135
 136     /**
 137      * Get all child groups associated with this object.
 138      */
 139     const std::map<std::string, Group *> &getStatGroups() const;
 140
 141     /**
 142      * Get all stats associated with this object.
 143      */
 144     const std::vector<Info *> &getStats() const;
 145
 146      /**
 147      * Add a stat block as a child of this block
 148      *
 149      * This method may only be called from a Group constructor or from
 150      * regStats. It's typically only called explicitly from Python
 151      * when setting up the SimObject hierarchy.
 152      */
 153     void addStatGroup(const char *name, Group *block);
 154
 155   private:
 156     /**
 157      * Merge the contents (stats & children) of a block to this block.
 158      *
 159      * This is called on a parent group by the child when it is being
 160      * merged into the parent.
 161      */
 162     void mergeStatGroup(Group *block);
 163
 164   private:
 165     /** Parent pointer if merged into parent */
 166     Group *const mergedParent;
 167
 168     std::map<std::string, Group *> statGroups;
 169     std::vector<Group *> mergedStatGroups;
 170     std::vector<Info *> stats;
 171 };
 172
 173 } // namespace Stats
 174
 175 #endif // __BASE_STATS_GROUP_HH__