X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;ds=sidebyside;f=libthreads.c;h=2ffe958ed193909cc2960fabcf28c9ee4d3eae4c;hb=dcd84cc88d70497bdc173c4bb78ce30afe4fb5c5;hp=bd7f501df3cc4c76a1d7bb30c982f66df802cc1e;hpb=6ac83ab66e4c564ffd0470ad25d5554eb5d52f28;p=model-checker.git

diff --git a/libthreads.c b/libthreads.c
index bd7f501..2ffe958 100644
--- a/libthreads.c
+++ b/libthreads.c
@@ -1,19 +1,25 @@
 #include <string.h>
 #include <stdlib.h>
 
-//#define CONFIG_DEBUG
-
 #include "libthreads.h"
+#include "schedule.h"
+#include "common.h"
 
-#define STACK_SIZE (1024 * 1024)
+/* global "model" object */
+#include "model.h"
 
-static struct thread *current, *main_thread;
+#define STACK_SIZE (1024 * 1024)
 
 static void *stack_allocate(size_t size)
 {
 	return malloc(size);
 }
 
+static void stack_free(void *stack)
+{
+	free(stack);
+}
+
 static int create_context(struct thread *t)
 {
 	int ret;
@@ -32,7 +38,7 @@ static int create_context(struct thread *t)
 	t->context.uc_stack.ss_sp = t->stack;
 	t->context.uc_stack.ss_size = STACK_SIZE;
 	t->context.uc_stack.ss_flags = 0;
-	t->context.uc_link = &main_thread->context;
+	t->context.uc_link = &model->system_thread->context;
 	makecontext(&t->context, t->start_routine, 1, t->arg);
 
 	return 0;
@@ -41,58 +47,68 @@ static int create_context(struct thread *t)
 static int create_initial_thread(struct thread *t)
 {
 	memset(t, 0, sizeof(*t));
+	model->assign_id(t);
 	return create_context(t);
 }
 
-static int thread_swap(struct thread *old, struct thread *new)
+static int thread_swap(struct thread *t1, struct thread *t2)
 {
-	return swapcontext(&old->context, &new->context);
+	return swapcontext(&t1->context, &t2->context);
 }
 
-static int thread_yield()
+static void thread_dispose(struct thread *t)
 {
-	struct thread *old, *next;
+	DEBUG("completed thread %d\n", thread_current()->id);
+	t->state = THREAD_COMPLETED;
+	stack_free(t->stack);
+}
 
-	DBG();
-	if (current) {
-		old = current;
-		schedule_add_thread(old);
-	} else {
-		old = main_thread;
+/*
+ * Return 1 if found next thread, 0 otherwise
+ */
+static int thread_system_next(void)
+{
+	struct thread *curr, *next;
+
+	curr = thread_current();
+	if (curr) {
+		if (curr->state == THREAD_READY)
+			model->scheduler->add_thread(curr);
+		else if (curr->state == THREAD_RUNNING)
+			/* Stopped while running; i.e., completed */
+			thread_dispose(curr);
+		else
+			DEBUG("ERROR: current thread in unexpected state??\n");
 	}
-	schedule_choose_next(&next);
-	current = next;
-	return thread_swap(old, next);
+	next = model->scheduler->next_thread();
+	if (next)
+		next->state = THREAD_RUNNING;
+	DEBUG("(%d, %d)\n", curr ? curr->id : -1, next ? next->id : -1);
+	if (!next)
+		return 1;
+	return thread_swap(model->system_thread, next);
 }
 
-static int master_thread_yield()
+static void thread_wait_finish(void)
 {
-	struct thread *next;
 
 	DBG();
 
-	if (current) {
-		DEBUG("completed thread %d\n", current->index);
-		current->completed = 1;
-	}
-	schedule_choose_next(&next);
-	if (next && !next->completed) {
-		current = next;
-		return thread_swap(main_thread, next);
-	}
-	return 1;
+	while (!thread_system_next());
 }
 
-int thread_create(struct thread *t, void (*start_routine), void *arg)
+/*
+ * User program API functions
+ */
+int thread_create(struct thread *t, void (*start_routine)(), void *arg)
 {
-	static int created = 1;
 	int ret = 0;
 
 	DBG();
 
 	memset(t, 0, sizeof(*t));
-	t->index = created++;
-	DEBUG("create thread %d\n", t->index);
+	model->assign_id(t);
+	DEBUG("create thread %d\n", t->id);
 
 	t->start_routine = start_routine;
 	t->arg = arg;
@@ -102,52 +118,53 @@ int thread_create(struct thread *t, void (*start_routine), void *arg)
 	if (ret)
 		return ret;
 
-	schedule_add_thread(t);
+	t->state = THREAD_CREATED;
+
+	model->scheduler->add_thread(t);
 	return 0;
 }
 
 void thread_join(struct thread *t)
 {
-	while (!t->completed)
+	while (t->state != THREAD_COMPLETED)
 		thread_yield();
 }
 
-void a(int *idx)
+int thread_yield(void)
 {
-	int i;
+	struct thread *old, *next;
 
-	for (i = 0; i < 10; i++) {
-		printf("Thread %d, loop %d\n", *idx, i);
-		if (i % 2)
-			thread_yield();
-	}
+	DBG();
+	old = thread_current();
+	old->state = THREAD_READY;
+	next = model->system_thread;
+	return thread_swap(old, next);
 }
 
-void user_main()
+struct thread *thread_current(void)
 {
-	struct thread t1, t2;
-	int i = 2, j = 3;
-
-	printf("%s() creating 2 threads\n", __func__);
-	thread_create(&t1, &a, &i);
-	thread_create(&t2, &a, &j);
-
-	thread_join(&t1);
-	thread_join(&t2);
-	printf("%s() is finished\n", __func__);
+	return model->scheduler->get_current_thread();
 }
 
+/*
+ * Main system function
+ */
 int main()
 {
 	struct thread user_thread;
+	struct thread *main_thread;
+
+	model = new ModelChecker();
 
-	main_thread = malloc(sizeof(struct thread));
+	main_thread = (struct thread *)malloc(sizeof(*main_thread));
 	create_initial_thread(main_thread);
+	model->add_system_thread(main_thread);
 
+	/* Start user program */
 	thread_create(&user_thread, &user_main, NULL);
 
 	/* Wait for all threads to complete */
-	while (master_thread_yield() == 0);
+	thread_wait_finish();
 
 	DEBUG("Exiting\n");
 	return 0;