src/mc/explo/DFSExplorer.hpp

   1 /* Copyright (c) 2008-2023. The SimGrid Team. All rights reserved.          */
   2
   3 /* This program is free software; you can redistribute it and/or modify it
   4  * under the terms of the license (GNU LGPL) which comes with this package. */
   5
   6 #ifndef SIMGRID_MC_SAFETY_CHECKER_HPP
   7 #define SIMGRID_MC_SAFETY_CHECKER_HPP
   8
   9 #include "src/mc/api/State.hpp"
  10 #include "src/mc/explo/Exploration.hpp"
  11
  12 #if SIMGRID_HAVE_STATEFUL_MC
  13 #include "src/mc/VisitedState.hpp"
  14 #endif
  15
  16 #include <list>
  17 #include <memory>
  18 #include <set>
  19 #include <string>
  20 #include <vector>
  21
  22 namespace simgrid::mc {
  23
  24 typedef std::list<std::shared_ptr<State>> stack_t;
  25
  26 /* Used to compare two stacks and decide which one is better to backtrack,
  27  * regarding the chosen guide in the last state. */
  28 class OpenedStatesCompare {
  29 public:
  30   bool operator()(std::shared_ptr<State> const& lhs, std::shared_ptr<State> const& rhs) const
  31   {
  32     return lhs->next_transition_guided().second > rhs->next_transition_guided().second;
  33   }
  34 };
  35
  36 class XBT_PRIVATE DFSExplorer : public Exploration {
  37
  38   XBT_DECLARE_ENUM_CLASS(ReductionMode, none, dpor);
  39
  40   ReductionMode reduction_mode_;
  41   unsigned long backtrack_count_      = 0; // for statistics
  42   unsigned long visited_states_count_ = 0; // for statistics
  43
  44   static xbt::signal<void(RemoteApp&)> on_exploration_start_signal;
  45   static xbt::signal<void(RemoteApp&)> on_backtracking_signal;
  46
  47   static xbt::signal<void(State*, RemoteApp&)> on_state_creation_signal;
  48
  49   static xbt::signal<void(State*, RemoteApp&)> on_restore_system_state_signal;
  50   static xbt::signal<void(RemoteApp&)> on_restore_initial_state_signal;
  51   static xbt::signal<void(Transition*, RemoteApp&)> on_transition_replay_signal;
  52   static xbt::signal<void(Transition*, RemoteApp&)> on_transition_execute_signal;
  53
  54   static xbt::signal<void(RemoteApp&)> on_log_state_signal;
  55
  56 public:
  57   explicit DFSExplorer(const std::vector<char*>& args, bool with_dpor, bool need_memory_info = false);
  58   void run() override;
  59   RecordTrace get_record_trace() override;
  60   std::vector<std::string> get_textual_trace() override;
  61   void log_state() override;
  62
  63   /** Called once when the exploration starts */
  64   static void on_exploration_start(std::function<void(RemoteApp& remote_app)> const& f)
  65   {
  66     on_exploration_start_signal.connect(f);
  67   }
  68   /** Called each time that the exploration backtracks from a exploration end */
  69   static void on_backtracking(std::function<void(RemoteApp& remote_app)> const& f)
  70   {
  71     on_backtracking_signal.connect(f);
  72   }
  73   /** Called each time that a new state is create */
  74   static void on_state_creation(std::function<void(State*, RemoteApp& remote_app)> const& f)
  75   {
  76     on_state_creation_signal.connect(f);
  77   }
  78   /** Called when rollbacking directly onto a previously checkpointed state */
  79   static void on_restore_system_state(std::function<void(State*, RemoteApp& remote_app)> const& f)
  80   {
  81     on_restore_system_state_signal.connect(f);
  82   }
  83   /** Called when the state to which we backtrack was not checkpointed state, forcing us to restore the initial state
  84    * before replaying some transitions */
  85   static void on_restore_initial_state(std::function<void(RemoteApp& remote_app)> const& f)
  86   {
  87     on_restore_initial_state_signal.connect(f);
  88   }
  89   /** Called when replaying a transition that was previously executed, to reach a backtracked state */
  90   static void on_transition_replay(std::function<void(Transition*, RemoteApp& remote_app)> const& f)
  91   {
  92     on_transition_replay_signal.connect(f);
  93   }
  94   /** Called when executing a new transition */
  95   static void on_transition_execute(std::function<void(Transition*, RemoteApp& remote_app)> const& f)
  96   {
  97     on_transition_execute_signal.connect(f);
  98   }
  99   /** Called when displaying the statistics at the end of the exploration */
 100   static void on_log_state(std::function<void(RemoteApp&)> const& f) { on_log_state_signal.connect(f); }
 101
 102 private:
 103   void check_non_termination(const State* current_state);
 104   void backtrack();
 105
 106   /** Stack representing the position in the exploration graph */
 107   stack_t stack_;
 108 #if SIMGRID_HAVE_STATEFUL_MC
 109   VisitedStates visited_states_;
 110   std::unique_ptr<VisitedState> visited_state_;
 111 #else
 112   void* visited_state_ = nullptr; /* The code uses it to detect whether we are doing stateful MC */
 113 #endif
 114
 115   /** Opened states are states that still contains todo actors.
 116    *  When backtracking, we pick a state from it*/
 117   std::multiset<std::shared_ptr<State>, OpenedStatesCompare> opened_states_;
 118
 119   /** Change current stack_ value to correspond to the one we would have
 120    *  had if we executed transition to get to state. This is required when
 121    *  backtracking, and achieved thanks to the fact states save their parent.*/
 122   void restore_stack(std::shared_ptr<State> state);
 123
 124   RecordTrace get_record_trace_of_stack(stack_t stack);
 125 };
 126
 127 } // namespace simgrid::mc
 128
 129 #endif