X-Git-Url: http://plrg.eecs.uci.edu/git/?p=model-checker.git;a=blobdiff_plain;f=threads.h;h=939676027ecea091b776735a0b372dcd515ad1ad;hp=44e1013768e911c6aaec6aa8564fd2a629b94cc7;hb=8362b1efa92635ab49bd937edf451e3b2e0981bc;hpb=5e5d8b86e9dbbfb4873adc717508f0b66679f13c

diff --git a/threads.h b/threads.h
index 44e1013..9396760 100644
--- a/threads.h
+++ b/threads.h
@@ -1,43 +1,132 @@
+/** @file threads.h
+ *  @brief Model Checker Thread class.
+ */
+
 #ifndef __THREADS_H__
 #define __THREADS_H__
 
 #include <ucontext.h>
+#include <stdint.h>
+#include <vector>
 
+#include "mymemory.h"
 #include "libthreads.h"
 
+typedef int thread_id_t;
+
 #define THREAD_ID_T_NONE	-1
 
+/** @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 has yielded to the model-checker but is ready to run. Used
+	 * during an action that caused a context switch to the model-checking
+	 * context.
+	 */
 	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:
-	void * operator new(size_t size);
-	void operator delete(void *ptr);
-	Thread(thrd_t *t, void (*func)(), void *a);
-	Thread(thrd_t *t);
+	Thread(thrd_t *t, void (*func)(void *), void *a);
 	~Thread();
 	void complete();
-	int swap(Thread *t);
+
+	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 thread to the waiting list for this thread.
+	 * @param t The Thread to add
+	 */
+	void push_wait_list(Thread *t) { wait_list.push_back(t); }
+
+	/**
+	 * Remove one Thread from the waiting list
+	 * @return The Thread that was removed from the waiting list
+	 */
+	Thread * pop_wait_list() {
+		Thread *ret = wait_list.front();
+		wait_list.pop_back();
+		return ret;
+	}
+
+	friend void thread_startup();
+
+	SNAPSHOTALLOC
 private:
 	int create_context();
+	Thread *parent;
+	ModelAction *creation;
 
-	void (*start_routine)();
+	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 Threads waiting on this Thread. Particularly, this list is
+	 * used for thread joins, where another Thread waits for this Thread to
+	 * complete
+	 */
+	std::vector<Thread *> 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;
 };
 
 Thread * thread_current();
@@ -47,4 +136,14 @@ 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_H__ */