+/** @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"
-
-#define VALUE_NONE -1
-
-typedef enum action_type {
- THREAD_CREATE,
- THREAD_YIELD,
- THREAD_JOIN,
- ATOMIC_READ,
- ATOMIC_WRITE
-} action_type_t;
-
-typedef std::list<class ModelAction *> action_list_t;
-
-class ModelAction {
-public:
- ModelAction(action_type_t type, memory_order order, void *loc, int value);
- void print(void);
-
- thread_id_t get_tid() { return tid; }
- action_type get_type() { return type; }
- memory_order get_mo() { return order; }
- void * get_location() { return location; }
-
- 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;
+#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 {
+ int maxreads;
};
-class Backtrack {
-public:
- Backtrack(ModelAction *d, action_list_t *t) {
- diverge = d;
- actionTrace = t;
- iter = actionTrace->begin();
- }
- ModelAction * get_diverge() { return diverge; }
- action_list_t * get_trace() { return actionTrace; }
- void advance_state() { iter++; }
- ModelAction * get_state() {
- return iter == actionTrace->end() ? NULL : *iter;
- }
-private:
- ModelAction *diverge;
- action_list_t *actionTrace;
- /* points to position in actionTrace as we replay */
- action_list_t::iterator iter;
+/**
+ * Structure for holding small ModelChecker members that should be snapshotted
+ */
+struct model_snapshot_members {
+ ModelAction *current_action;
+ int next_thread_id;
+ modelclock_t used_sequence_numbers;
+ Thread *nextThread;
+ ModelAction *next_backtrack;
+
+ /** @see ModelChecker::lazy_sync_size */
+ unsigned int lazy_sync_size;
};
+/** @brief The central structure for model-checking */
class ModelChecker {
public:
- ModelChecker();
+ ModelChecker(struct model_params params);
~ModelChecker();
- class Scheduler *scheduler;
- Thread *system_thread;
- void add_system_thread(Thread *t);
+ /** @returns the context for the main model-checking system thread */
+ ucontext_t * get_system_context() { return &system_context; }
- void set_current_action(ModelAction *act) { current_action = act; }
- void check_current_action(void);
- void print_summary(void);
- Thread * schedule_next_thread();
+ /** Prints an execution summary with trace information. */
+ void print_summary();
- int add_thread(Thread *t);
+ void add_thread(Thread *t);
void remove_thread(Thread *t);
- Thread * get_thread(thread_id_t tid) { return thread_map[tid]; }
+ Thread * get_thread(thread_id_t tid) { return thread_map->get(id_to_int(tid)); }
- int get_next_id();
+ thread_id_t get_next_id();
+ int get_num_threads();
+ modelclock_t get_next_seq_num();
- int switch_to_master(ModelAction *act);
+ /** @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);
+ ModelAction * get_parent_action(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();
+ bool isfeasibleprefix();
+ void set_assert() {asserted=true;}
+
+ MEMALLOC
private:
- int used_thread_id;
+ /** The scheduler to use: tracks the running/ready Threads */
+ Scheduler *scheduler;
+
+ bool has_asserted() {return asserted;}
+ void reset_asserted() {asserted=false;}
int num_executions;
+ 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) { priv->current_action = act; }
+ Thread * check_current_action(ModelAction *curr);
+ bool process_read(ModelAction *curr, Thread * th, bool second_part_of_rmw);
+
+ bool take_step();
+
+ void check_recency(ModelAction *curr, bool already_added);
ModelAction * get_last_conflict(ModelAction *act);
void set_backtracking(ModelAction *act);
- thread_id_t advance_backtracking_state();
- thread_id_t get_next_replay_thread();
- Backtrack * get_next_backtrack();
+ Thread * get_next_thread(ModelAction *curr);
+ ModelAction * get_next_backtrack();
void reset_to_initial_state();
+ bool 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_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);
+ bool r_modification_order(ModelAction *curr, const ModelAction *rf);
+ bool w_modification_order(ModelAction *curr);
+ bool release_seq_head(const ModelAction *rf,
+ std::vector<const ModelAction *> *release_heads) const;
+ bool resolve_release_sequences(void *location);
- class ModelAction *current_action;
- Backtrack *exploring;
- thread_id_t nextThread;
+ ModelAction *diverge;
+ ucontext_t system_context;
action_list_t *action_trace;
- std::map<thread_id_t, class Thread *> thread_map;
- class TreeNode *rootNode, *currentNode;
- std::list<class Backtrack *> backtrack_list;
+ 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;
+
+ /**
+ * Collection of lists of objects that might synchronize with one or
+ * more release sequence. Release sequences might be determined lazily
+ * as promises are fulfilled and modification orders are established.
+ * This structure maps its lists by object location. Each ModelAction
+ * in the lists should be an acquire operation.
+ */
+ HashTable<void *, std::list<ModelAction *>, uintptr_t, 4> *lazy_sync_with_release;
+
+ /**
+ * Represents the total size of the
+ * ModelChecker::lazy_sync_with_release lists. This count should be
+ * snapshotted, so it is actually a pointer to a location within
+ * ModelChecker::priv
+ */
+ unsigned int *lazy_sync_size;
+
+ std::vector<ModelAction *> *thrd_last_action;
+ NodeStack *node_stack;
+
+ /** Private data members that should be snapshotted. They are grouped
+ * together for efficiency and maintainability. */
+ struct model_snapshot_members *priv;
+
+ /**
+ * @brief The modification order graph
+ *
+ * A directed 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;
+ bool too_many_reads;
+ bool asserted;
};
extern ModelChecker *model;
-int thread_switch_to_master(ModelAction *act);
-
#endif /* __MODEL_H__ */
projects / model-checker.git / blobdiff