X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=threads.h;h=91db236f4bddb904fbd7944c35c00b39bbfce092;hb=9db4729d3e6ab5f3ec5fd8a2560d95026332fecf;hp=e7cd792a134c4b5e223b6f9465af4eaf83753b1e;hpb=baf7877f639380a66770d974ad4312c42dda338b;p=model-checker.git

diff --git a/threads.h b/threads.h
index e7cd792..91db236 100644
--- a/threads.h
+++ b/threads.h
@@ -7,13 +7,11 @@
 
 #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
+#include "modeltypes.h"
 
 /** @brief Represents the state of a user Thread */
 typedef enum thread_state {
@@ -21,12 +19,13 @@ typedef enum thread_state {
 	THREAD_CREATED,
 	/** Thread is running */
 	THREAD_RUNNING,
+	/** Thread is not currently running but is ready to run */
+	THREAD_READY,
 	/**
-	 * 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 is waiting on another action (e.g., thread completion, lock
+	 * release, etc.)
 	 */
-	THREAD_READY,
+	THREAD_BLOCKED,
 	/** Thread has completed its execution */
 	THREAD_COMPLETED
 } thread_state;
@@ -36,6 +35,7 @@ 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();
@@ -67,14 +67,57 @@ public:
 	 */
 	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();
 
-	SNAPSHOTALLOC
+	/**
+	 * 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;
@@ -83,12 +126,22 @@ private:
 	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();