X-Git-Url: http://plrg.eecs.uci.edu/git/?p=model-checker.git;a=blobdiff_plain;f=threads.h;h=9456a22f2fe4942b1004a87794fa3474eaeab26b;hp=e52c324eb0fb81119d8063625c21387443105b18;hb=c1cc5e279bcba4216bde88a63dafac96d3ef47ba;hpb=9fd8ac15f03e8ca01a20563e06c44b8b93090892

diff --git a/threads.h b/threads.h
index e52c324..9456a22 100644
--- a/threads.h
+++ b/threads.h
@@ -1,7 +1,14 @@
+/** @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"
 
@@ -9,13 +16,26 @@ 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 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(thrd_t *t, void (*func)(void *), void *a);
@@ -31,13 +51,60 @@ public:
 	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); }
+
+	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;
+	}
+
 	friend void thread_startup();
 
 	SNAPSHOTALLOC
 private:
 	int create_context();
 	Thread *parent;
+	ModelAction *creation;
 
+	ModelAction *pending;
 	void (*start_routine)(void *);
 	void *arg;
 	ucontext_t context;
@@ -45,6 +112,20 @@ private:
 	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 *> 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();