+/** @file threads-model.h
+ * @brief Model Checker Thread class.
+ */
+
+#ifndef __THREADS_MODEL_H__
+#define __THREADS_MODEL_H__
+
+#include <ucontext.h>
+#include <stdint.h>
+#include <vector>
+
+#include "mymemory.h"
+#include "libthreads.h"
+#include "modeltypes.h"
+
+/** @brief Represents the state of a user Thread */
+typedef enum thread_state {
+ /** Thread was just created and hasn't run yet */
+ THREAD_CREATED,
+ /** Thread is running */
+ THREAD_RUNNING,
+ /** Thread is not currently running but is ready to run */
+ THREAD_READY,
+ /**
+ * Thread is waiting on another action (e.g., thread completion, lock
+ * release, etc.)
+ */
+ THREAD_BLOCKED,
+ /** Thread has completed its execution */
+ THREAD_COMPLETED
+} thread_state;
+
+class ModelAction;
+
+/** @brief A Thread is created for each user-space thread */
+class Thread {
+public:
+ Thread(thread_id_t tid);
+ Thread(thrd_t *t, void (*func)(void *), void *a);
+ ~Thread();
+ void complete();
+
+ static int swap(ucontext_t *ctxt, Thread *t);
+ static int swap(Thread *t, ucontext_t *ctxt);
+
+ thread_state get_state() { return state; }
+ void set_state(thread_state s) { state = s; }
+ thread_id_t get_id();
+ thrd_t get_thrd_t() { return *user_thread; }
+ Thread * get_parent() { return parent; }
+
+ void set_creation(ModelAction *act) { creation = act; }
+ ModelAction * get_creation() { return creation; }
+
+ /**
+ * Set a return value for the last action in this thread (e.g., for an
+ * atomic read).
+ * @param value The value to return
+ */
+ void set_return_value(uint64_t value) { last_action_val = value; }
+
+ /**
+ * Retrieve a return value for the last action in this thread. Used,
+ * for instance, for an atomic read to return the 'read' value. Should
+ * be called from a user context.
+ * @return The value 'returned' by the action
+ */
+ uint64_t get_return_value() { return last_action_val; }
+
+ /** @return True if this thread is finished executing */
+ bool is_complete() { return state == THREAD_COMPLETED; }
+
+ /** @return True if this thread is blocked */
+ bool is_blocked() { return state == THREAD_BLOCKED; }
+
+ /** @return True if no threads are waiting on this Thread */
+ bool wait_list_empty() { return wait_list.empty(); }
+
+ /**
+ * Add a ModelAction to the waiting list for this thread.
+ * @param t The ModelAction to add. Must be a JOIN.
+ */
+ void push_wait_list(ModelAction *act) { wait_list.push_back(act); }
+
+ unsigned int num_wait_list() {
+ return wait_list.size();
+ }
+
+ ModelAction * get_waiter(unsigned int i) {
+ return wait_list[i];
+ }
+
+ ModelAction * get_pending() { return pending; }
+ void set_pending(ModelAction *act) { pending = act; }
+ /**
+ * Remove one ModelAction from the waiting list
+ * @return The ModelAction that was removed from the waiting list
+ */
+ ModelAction * pop_wait_list() {
+ ModelAction *ret = wait_list.front();
+ wait_list.pop_back();
+ return ret;
+ }
+
+ bool is_model_thread() { return model_thread; }
+
+ friend void thread_startup();
+
+ /**
+ * Intentionally NOT allocated with MODELALLOC or SNAPSHOTALLOC.
+ * Threads should be allocated on the user's normal (snapshotting) heap
+ * to allow their allocation/deallocation to follow the same pattern as
+ * the rest of the backtracked/replayed program.
+ */
+private:
+ int create_context();
+ Thread *parent;
+ ModelAction *creation;
+
+ ModelAction *pending;
+ void (*start_routine)(void *);
+ void *arg;
+ ucontext_t context;
+ void *stack;
+ thrd_t *user_thread;
+ thread_id_t id;
+ thread_state state;
+
+ /**
+ * A list of ModelActions waiting on this Thread. Particularly, this
+ * list is used for thread joins, where another Thread waits for this
+ * Thread to complete
+ */
+ std::vector< ModelAction *, SnapshotAlloc<ModelAction *> > wait_list;
+
+ /**
+ * The value returned by the last action in this thread
+ * @see Thread::set_return_value()
+ * @see Thread::get_return_value()
+ */
+ uint64_t last_action_val;
+
+ /** @brief Is this Thread a special model-checker thread? */
+ const bool model_thread;
+};
+
+Thread * thread_current();
+
+static inline thread_id_t thrd_to_id(thrd_t t)
+{
+ return t;
+}
+
+static inline thread_id_t int_to_id(int i)
+{
+ return i;
+}
+
+static inline int id_to_int(thread_id_t id)
+{
+ return id;
+}
+
+#endif /* __THREADS_MODEL_H__ */
projects / model-checker.git / commitdiff