+/** @file model.h
+ * @brief Core model checker.
+ */
+
#ifndef __MODEL_H__
#define __MODEL_H__
#include <list>
-#include <map>
+#include <vector>
+#include <cstddef>
+#include <ucontext.h>
#include "schedule.h"
+#include "mymemory.h"
#include "libthreads.h"
-#include "libatomic.h"
#include "threads.h"
-#include "tree.h"
+#include "action.h"
+#include "clockvector.h"
+#include "hashtable.h"
+
+/* Forward declaration */
+class NodeStack;
+class CycleGraph;
+class Promise;
+
+/**
+ * Model checker parameter structure. Holds run-time configuration options for
+ * the model checker.
+ */
+struct model_params {
+};
-#define VALUE_NONE -1
+/** @brief The central structure for model-checking */
+class ModelChecker {
+public:
+ ModelChecker(struct model_params params);
+ ~ModelChecker();
-typedef enum action_type {
- THREAD_CREATE,
- THREAD_YIELD,
- THREAD_JOIN,
- ATOMIC_READ,
- ATOMIC_WRITE
-} action_type_t;
+ /** @returns the context for the main model-checking system thread */
+ ucontext_t * get_system_context() { return &system_context; }
-typedef std::list<class ModelAction *> action_list_t;
+ /** Prints an execution summary with trace information. */
+ void print_summary();
-class ModelAction {
-public:
- ModelAction(action_type_t type, memory_order order, void *loc, int value);
- void print(void);
+ Thread * schedule_next_thread();
- thread_id_t get_tid() { return tid; }
- action_type get_type() { return type; }
- memory_order get_mo() { return order; }
- void *get_location() { return location; }
+ void add_thread(Thread *t);
+ void remove_thread(Thread *t);
+ Thread * get_thread(thread_id_t tid) { return thread_map->get(id_to_int(tid)); }
- TreeNode *get_node() { return node; }
- void set_node(TreeNode *n) { node = n; }
-private:
- action_type type;
- memory_order order;
- void *location;
- thread_id_t tid;
- int value;
- TreeNode *node;
-};
+ thread_id_t get_next_id();
+ int get_num_threads();
+ modelclock_t get_next_seq_num();
-class Backtrack {
-public:
- Backtrack(ModelAction *d, action_list_t *t) {
- diverge = d;
- actionTrace = t;
- //currentIterator = actionTrace->getFirst();
- }
- ModelAction *get_diverge() { return diverge; }
- action_list_t *get_trace() { return actionTrace; }
+ /** @return The currently executing Thread. */
+ Thread * get_current_thread() { return scheduler->get_current_thread(); }
+
+ int switch_to_master(ModelAction *act);
+ ClockVector * get_cv(thread_id_t tid);
+ bool next_execution();
+ bool isfeasible();
+ bool isfinalfeasible();
+ void check_promises(ClockVector *old_cv, ClockVector * merge_cv);
+ void get_release_seq_heads(ModelAction *act,
+ std::vector<const ModelAction *> *release_heads);
+
+ void finish_execution();
+
+ MEMALLOC
private:
- ModelAction *diverge;
- /* unused for now; will be used when re-exploring this path? */
- //MyListElement *currentIterator;
- action_list_t *actionTrace;
-};
+ /** The scheduler to use: tracks the running/ready Threads */
+ Scheduler *scheduler;
-class ModelChecker {
-public:
- ModelChecker();
- ~ModelChecker();
- class Scheduler *scheduler;
- Thread *system_thread;
+ int next_thread_id;
+ modelclock_t used_sequence_numbers;
+ int num_executions;
- void add_system_thread(Thread *t);
+ const model_params params;
+ /**
+ * Stores the ModelAction for the current thread action. Call this
+ * immediately before switching from user- to system-context to pass
+ * data between them.
+ * @param act The ModelAction created by the user-thread action
+ */
void set_current_action(ModelAction *act) { current_action = act; }
- ModelAction *get_last_conflict(ModelAction *act);
- void check_current_action(void);
- void set_backtracking(ModelAction *act);
- void print_trace(void);
+ void check_current_action();
- int add_thread(Thread *t);
- Thread *get_thread(thread_id_t tid) { return thread_map[tid]; }
+ bool take_step();
- void assign_id(Thread *t);
+ ModelAction * get_last_conflict(ModelAction *act);
+ void set_backtracking(ModelAction *act);
+ thread_id_t get_next_replay_thread();
+ ModelAction * get_next_backtrack();
+ void reset_to_initial_state();
+ void resolve_promises(ModelAction *curr);
+ void compute_promises(ModelAction *curr);
+
+ void add_action_to_lists(ModelAction *act);
+ ModelAction * get_last_action(thread_id_t tid);
+ ModelAction * get_parent_action(thread_id_t tid);
+ ModelAction * get_last_seq_cst(const void *location);
+ void build_reads_from_past(ModelAction *curr);
+ ModelAction * process_rmw(ModelAction *curr);
+ void post_r_modification_order(ModelAction *curr, const ModelAction *rf);
+ void r_modification_order(ModelAction *curr, const ModelAction *rf);
+ void w_modification_order(ModelAction *curr);
+ bool release_seq_head(const ModelAction *rf,
+ std::vector<const ModelAction *> *release_heads) const;
+
+ ModelAction *current_action;
+ ModelAction *diverge;
+ thread_id_t nextThread;
- int switch_to_master(ModelAction *act);
-private:
- int used_thread_id;
- class ModelAction *current_action;
+ ucontext_t system_context;
action_list_t *action_trace;
- std::map<thread_id_t, class Thread *> thread_map;
- class TreeNode *rootNode, *currentNode;
+ HashTable<int, Thread *, int> *thread_map;
+
+ /** Per-object list of actions. Maps an object (i.e., memory location)
+ * to a trace of all actions performed on the object. */
+ HashTable<const void *, action_list_t, uintptr_t, 4> *obj_map;
+
+ HashTable<void *, std::vector<action_list_t>, uintptr_t, 4 > *obj_thrd_map;
+ std::vector<Promise *> *promises;
+ std::vector<ModelAction *> *thrd_last_action;
+ NodeStack *node_stack;
+ ModelAction *next_backtrack;
+
+ /**
+ * @brief The modification order graph
+ *
+ * A direceted acyclic graph recording observations of the modification
+ * order on all the atomic objects in the system. This graph should
+ * never contain any cycles, as that represents a violation of the
+ * memory model (total ordering). This graph really consists of many
+ * disjoint (unconnected) subgraphs, each graph corresponding to a
+ * separate ordering on a distinct object.
+ *
+ * The edges in this graph represent the "ordered before" relation,
+ * such that <tt>a --> b</tt> means <tt>a</tt> was ordered before
+ * <tt>b</tt>.
+ */
+ CycleGraph *mo_graph;
+
+ bool failed_promise;
};
extern ModelChecker *model;
-int thread_switch_to_master(ModelAction *act);
-
#endif /* __MODEL_H__ */