ceph/src/crush/CrushTreeDumper.h

   1 // -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
   2 // vim: ts=8 sw=2 smarttab
   3 /*
   4  * Ceph distributed storage system
   5  *
   6  * Copyright (C) 2015 Mirantis Inc
   7  *
   8  * Author: Mykola Golub <mgolub@mirantis.com>
   9  *
  10  *  This library is free software; you can redistribute it and/or
  11  *  modify it under the terms of the GNU Lesser General Public
  12  *  License as published by the Free Software Foundation; either
  13  *  version 2.1 of the License, or (at your option) any later version.
  14  *
  15  */
  16
  17 #ifndef CRUSH_TREE_DUMPER_H
  18 #define CRUSH_TREE_DUMPER_H
  19
  20 #include "CrushWrapper.h"
  21
  22 /**
  23  * CrushTreeDumper:
  24  * A helper class and functions to dump a crush tree.
  25  *
  26  * Example:
  27  *
  28  *  class SimpleDumper : public CrushTreeDumper::Dumper<ostream> {
  29  *  public:
  30  *    SimpleDumper(const CrushWrapper *crush) :
  31  *      CrushTreeDumper::Dumper<ostream>(crush) {}
  32  *  protected:
  33  *    virtual void dump_item(const CrushTreeDumper::Item &qi, ostream *out) {
  34  *      *out << qi.id;
  35  *      for (int k = 0; k < qi.depth; k++)
  36  *        *out << "-";
  37  *      if (qi.is_bucket())
  38  *        *out << crush->get_item_name(qi.id)
  39  *      else
  40  *        *out << "osd." << qi.id;
  41  *      *out << "\n";
  42  *    }
  43  *  };
  44  *
  45  *  SimpleDumper(crush).dump(out);
  46  *
  47  */
  48
  49 namespace CrushTreeDumper {
  50
  51   struct Item {
  52     int id;
  53     int depth;
  54     float weight;
  55     list<int> children;
  56
  57     Item() : id(0), depth(0), weight(0) {}
  58     Item(int i, int d, float w) : id(i), depth(d), weight(w) {}
  59
  60     bool is_bucket() const { return id < 0; }
  61   };
  62
  63   template <typename F>
  64   class Dumper : public list<Item> {
  65   public:
  66     explicit Dumper(const CrushWrapper *crush_) : crush(crush_) {
  67       crush->find_roots(roots);
  68       root = roots.begin();
  69     }
  70
  71     virtual ~Dumper() {}
  72
  73     virtual void reset() {
  74       root = roots.begin();
  75       touched.clear();
  76       clear();
  77     }
  78
  79     bool next(Item &qi) {
  80       if (empty()) {
  81         if (root == roots.end())
  82           return false;
  83         push_back(Item(*root, 0, crush->get_bucket_weightf(*root)));
  84         ++root;
  85       }
  86
  87       qi = front();
  88       pop_front();
  89       touched.insert(qi.id);
  90
  91       if (qi.is_bucket()) {
  92         // queue bucket contents...
  93         int s = crush->get_bucket_size(qi.id);
  94         for (int k = s - 1; k >= 0; k--) {
  95           int id = crush->get_bucket_item(qi.id, k);
  96           qi.children.push_back(id);
  97           push_front(Item(id, qi.depth + 1,
  98                           crush->get_bucket_item_weightf(qi.id, k)));
  99         }
 100       }
 101       return true;
 102     }
 103
 104     void dump(F *f) {
 105       reset();
 106       Item qi;
 107       while (next(qi))
 108         dump_item(qi, f);
 109     }
 110
 111     bool is_touched(int id) const { return touched.count(id) > 0; }
 112
 113   protected:
 114     virtual void dump_item(const Item &qi, F *f) = 0;
 115
 116   protected:
 117     const CrushWrapper *crush;
 118
 119   private:
 120     set<int> touched;
 121     set<int> roots;
 122     set<int>::iterator root;
 123   };
 124
 125   inline void dump_item_fields(const CrushWrapper *crush,
 126                                const Item &qi, Formatter *f) {
 127     f->dump_int("id", qi.id);
 128     if (qi.is_bucket()) {
 129       int type = crush->get_bucket_type(qi.id);
 130       f->dump_string("name", crush->get_item_name(qi.id));
 131       f->dump_string("type", crush->get_type_name(type));
 132       f->dump_int("type_id", type);
 133     } else {
 134       f->dump_stream("name") << "osd." << qi.id;
 135       f->dump_string("type", crush->get_type_name(0));
 136       f->dump_int("type_id", 0);
 137       f->dump_float("crush_weight", qi.weight);
 138       f->dump_unsigned("depth", qi.depth);
 139     }
 140   }
 141
 142   inline void dump_bucket_children(const CrushWrapper *crush,
 143                                    const Item &qi, Formatter *f) {
 144     if (!qi.is_bucket())
 145       return;
 146
 147     f->open_array_section("children");
 148     for (list<int>::const_iterator i = qi.children.begin();
 149          i != qi.children.end();
 150          ++i) {
 151       f->dump_int("child", *i);
 152     }
 153     f->close_section();
 154   }
 155
 156   class FormattingDumper : public Dumper<Formatter> {
 157   public:
 158     explicit FormattingDumper(const CrushWrapper *crush) : Dumper<Formatter>(crush) {}
 159
 160   protected:
 161     void dump_item(const Item &qi, Formatter *f) override {
 162       f->open_object_section("item");
 163       dump_item_fields(qi, f);
 164       dump_bucket_children(qi, f);
 165       f->close_section();
 166     }
 167
 168     virtual void dump_item_fields(const Item &qi, Formatter *f) {
 169       CrushTreeDumper::dump_item_fields(crush, qi, f);
 170     }
 171
 172     virtual void dump_bucket_children(const Item &qi, Formatter *f) {
 173       CrushTreeDumper::dump_bucket_children(crush, qi, f);
 174     }
 175   };
 176
 177 }
 178
 179 #endif