2 * @brief Core model checker.
15 #include "hashtable.h"
16 #include "workqueue.h"
18 #include "modeltypes.h"
20 /* Forward declaration */
27 /** @brief Shorthand for a list of release sequence heads */
28 typedef std::vector< const ModelAction *, ModelAlloc<const ModelAction *> > rel_heads_list_t;
31 * Model checker parameter structure. Holds run-time configuration options for
37 unsigned int fairwindow;
38 unsigned int enabledcount;
41 struct PendingFutureValue {
43 modelclock_t expiration;
48 * Structure for holding small ModelChecker members that should be snapshotted
50 struct model_snapshot_members {
51 ModelAction *current_action;
53 modelclock_t used_sequence_numbers;
55 ModelAction *next_backtrack;
58 /** @brief The central structure for model-checking */
61 ModelChecker(struct model_params params);
64 /** @returns the context for the main model-checking system thread */
65 ucontext_t * get_system_context() { return &system_context; }
67 /** Prints an execution summary with trace information. */
69 #if SUPPORT_MOD_ORDER_DUMP
70 void dumpGraph(char *filename);
73 void add_thread(Thread *t);
74 void remove_thread(Thread *t);
75 Thread * get_thread(thread_id_t tid);
76 Thread * get_thread(ModelAction *act);
78 thread_id_t get_next_id();
79 int get_num_threads();
80 Thread * get_current_thread();
82 int switch_to_master(ModelAction *act);
83 ClockVector * get_cv(thread_id_t tid);
84 ModelAction * get_parent_action(thread_id_t tid);
85 bool next_execution();
87 bool isfeasibleotherthanRMW();
88 bool isfinalfeasible();
89 void check_promises(ClockVector *old_cv, ClockVector * merge_cv);
90 void get_release_seq_heads(ModelAction *act, rel_heads_list_t *release_heads);
91 void finish_execution();
92 bool isfeasibleprefix();
93 void set_assert() {asserted=true;}
95 /** @brief Alert the model-checker that an incorrectly-ordered
96 * synchronization was made */
97 void set_bad_synchronization() { bad_synchronization = true; }
99 const model_params params;
103 /** The scheduler to use: tracks the running/ready Threads */
104 Scheduler *scheduler;
106 bool thin_air_constraint_may_allow(const ModelAction * writer, const ModelAction *reader);
107 bool has_asserted() {return asserted;}
108 void reset_asserted() {asserted=false;}
110 int num_feasible_executions;
111 bool promises_expired();
113 modelclock_t get_next_seq_num();
116 * Stores the ModelAction for the current thread action. Call this
117 * immediately before switching from user- to system-context to pass
119 * @param act The ModelAction created by the user-thread action
121 void set_current_action(ModelAction *act) { priv->current_action = act; }
122 Thread * check_current_action(ModelAction *curr);
123 ModelAction * initialize_curr_action(ModelAction *curr);
124 bool process_read(ModelAction *curr, bool second_part_of_rmw);
125 bool process_write(ModelAction *curr);
126 bool process_mutex(ModelAction *curr);
127 bool process_thread_action(ModelAction *curr);
128 bool check_action_enabled(ModelAction *curr);
132 void check_recency(ModelAction *curr, const ModelAction *rf);
133 ModelAction * get_last_conflict(ModelAction *act);
134 void set_backtracking(ModelAction *act);
135 Thread * get_next_thread(ModelAction *curr);
136 ModelAction * get_next_backtrack();
137 void reset_to_initial_state();
138 bool resolve_promises(ModelAction *curr);
139 void compute_promises(ModelAction *curr);
141 void check_curr_backtracking(ModelAction * curr);
142 void add_action_to_lists(ModelAction *act);
143 ModelAction * get_last_action(thread_id_t tid) const;
144 ModelAction * get_last_seq_cst(ModelAction *curr) const;
145 ModelAction * get_last_unlock(ModelAction *curr) const;
146 void build_reads_from_past(ModelAction *curr);
147 ModelAction * process_rmw(ModelAction *curr);
148 void post_r_modification_order(ModelAction *curr, const ModelAction *rf);
149 bool r_modification_order(ModelAction *curr, const ModelAction *rf);
150 bool w_modification_order(ModelAction *curr);
151 bool release_seq_head(const ModelAction *rf, rel_heads_list_t *release_heads) const;
152 bool resolve_release_sequences(void *location, work_queue_t *work_queue);
153 void do_complete_join(ModelAction *join);
155 ModelAction *diverge;
156 ModelAction *earliest_diverge;
158 ucontext_t system_context;
159 action_list_t *action_trace;
160 HashTable<int, Thread *, int> *thread_map;
162 /** Per-object list of actions. Maps an object (i.e., memory location)
163 * to a trace of all actions performed on the object. */
164 HashTable<const void *, action_list_t, uintptr_t, 4> *obj_map;
166 /** Per-object list of actions. Maps an object (i.e., memory location)
167 * to a trace of all actions performed on the object. */
168 HashTable<const void *, action_list_t, uintptr_t, 4> *lock_waiters_map;
170 HashTable<void *, std::vector<action_list_t>, uintptr_t, 4 > *obj_thrd_map;
171 std::vector<Promise *> *promises;
172 std::vector<struct PendingFutureValue> *futurevalues;
175 * List of acquire actions that might synchronize with one or more
176 * release sequence. Release sequences might be determined lazily as
177 * promises are fulfilled and modification orders are established. Each
178 * ModelAction in this list must be an acquire operation.
180 std::vector<ModelAction *> *pending_acq_rel_seq;
182 std::vector<ModelAction *> *thrd_last_action;
183 NodeStack *node_stack;
185 /** Private data members that should be snapshotted. They are grouped
186 * together for efficiency and maintainability. */
187 struct model_snapshot_members *priv;
190 * @brief The modification order graph
192 * A directed acyclic graph recording observations of the modification
193 * order on all the atomic objects in the system. This graph should
194 * never contain any cycles, as that represents a violation of the
195 * memory model (total ordering). This graph really consists of many
196 * disjoint (unconnected) subgraphs, each graph corresponding to a
197 * separate ordering on a distinct object.
199 * The edges in this graph represent the "ordered before" relation,
200 * such that <tt>a --> b</tt> means <tt>a</tt> was ordered before
203 CycleGraph *mo_graph;
207 /** @brief Incorrectly-ordered synchronization was made */
208 bool bad_synchronization;
211 extern ModelChecker *model;
213 #endif /* __MODEL_H__ */