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