X-Git-Url: http://plrg.eecs.uci.edu/git/?p=model-checker.git;a=blobdiff_plain;f=model.h;h=c3e5830211c9276ec7b5004504fbb9472df32069;hp=b2bcb96f54a79513a6eb7c7890c796a4203f0299;hb=50b95c3747f4fe79b2ab1a1a6fc303224e16e418;hpb=612a0d9b6537c8c24bcbaed2cf23a73fff65f5f1 diff --git a/model.h b/model.h index b2bcb96..c3e5830 100644 --- a/model.h +++ b/model.h @@ -1,83 +1,186 @@ +/** @file model.h + * @brief Core model checker. + */ + #ifndef __MODEL_H__ #define __MODEL_H__ #include -#include +#include #include #include #include "schedule.h" +#include "mymemory.h" #include "libthreads.h" -#include "libatomic.h" #include "threads.h" #include "action.h" +#include "clockvector.h" +#include "hashtable.h" /* Forward declaration */ -class TreeNode; +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; - void set_system_context(ucontext_t *ctxt) { system_context = ctxt; } - ucontext_t * get_system_context(void) { return system_context; } + /** @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[id_to_int(tid)]; } + Thread * get_thread(thread_id_t tid) { return thread_map->get(id_to_int(tid)); } 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 *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 *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; + ucontext_t system_context; action_list_t *action_trace; - std::map thread_map; - class TreeNode *rootNode, *currentNode; - std::list backtrack_list; + HashTable *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 *obj_map; + + HashTable, uintptr_t, 4 > *obj_thrd_map; + std::vector *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, 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 *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 a --> b means a was ordered before + * b. + */ + CycleGraph *mo_graph; + bool failed_promise; + bool too_many_reads; + bool asserted; }; extern ModelChecker *model;