Add working? solution

Assignment5/hard_affinity.c

@@ -8,25 +8,26 @@
 
 // TODO: Need to use semaphore for thread synchronization, and mutex for shared variables
 
+// Need to make sure both threads read time once, or only tick once per time increment
+
 
 #define MAX_USERNAME_LENGTH 100
 int QUANTUM;
 int CPUS;
-int TIME = 0;
 
 // Semaphore for the threads to simulate
-sem_t sim_sem;
-
-// Semaphore for the thread to control printing
 sem_t print_sem;
 
-// Mutex for simulation
-pthread_mutex_t sim_mutex;
+sem_t sim_sem;
 
 // Mutex for thread finish count
 pthread_mutex_t finish_mutex;
 int finish_count = 0;
 
+// Mutex for global time
+pthread_mutex_t time_mutex;
+int TIME = 1;
+
 typedef struct ThreadArgs {
 	int cpu_id;
 	char *print_buffer;
@@ -64,6 +65,18 @@ Queue *input_queue() {
 	return queue;
 }
 
+int getTime() {
+    pthread_mutex_lock(&time_mutex);
+    int time = TIME;
+    pthread_mutex_unlock(&time_mutex);
+    return time;
+}
+void incrementTime() {
+    pthread_mutex_lock(&time_mutex);
+    TIME++;
+    pthread_mutex_unlock(&time_mutex);
+}
+
 void *print(void *args) {
 	// Cast args and create local variables
 	ThreadArgs *thread_args = (ThreadArgs *) args;
@@ -78,39 +91,30 @@ void *print(void *args) {
 	}
 	printf("\n");
 
-	int test = 0;
-
 	while (true) {
-		pthread_mutex_lock(&sim_mutex);
+        sem_wait(&print_sem);
+        int time = getTime();
+
+        // Print the time and the print buffer
+		printf("%d", time);
+		for (int i = 0; i < CPUS; ++i) {
+            printf("\t%c",  print_buffer[i]);
+		}
+        printf("\n");
+
+        // Check if every process is done
         if (finish_count == CPUS) {
             break;
         }
 
-		printf("%d", TIME);
+        incrementTime();
 
+        // Increment the simulation semaphore to let the simulation threads run
         for (int i = 0; i < CPUS; ++i) {
-			// Allow the simulation to begin
-			//sem_post(&sim_sem);
-
-			// Wait for the simulation to finish
-			//sem_wait(&print_sem);
-
-
-			for (int j = 0; j < CPUS; ++j) {
-
-				printf("\t%c",  print_buffer[j]);
+            sem_post(&sim_sem);
         }
 
 	}
-		printf("\n");
-		TIME++;
-
-		test++;
-		if (test == 35) {
-			break;
-		}
-		pthread_mutex_unlock(&sim_mutex);
-	}
 
 	// Print the summary
 	printf("\nSummary\n");
@@ -128,22 +132,31 @@ void *simulation(void *args) {
 	char *print_buffer = thread_args->print_buffer;
 	int cpu_id = thread_args->cpu_id;
 
-
 	// Loop variables
 	int quantum = QUANTUM;
 	int addedJobs = 0;
 	Process *process = NULL;
+    int numberOfJobsForThisCPU = 0;
+
+    // Count number of jobs this CPU has to do
+    process = in_queue->end;
+    for (int i = 0; i < in_queue->size; ++i) {
+        if (process->affinity == cpu_id) {
+            numberOfJobsForThisCPU++;
+        }
+        process = process->prev_elem;
+    }
 
 	// Create a queue for the simulation
 	Queue *sim_queue = createQueue();
 	while (true) {
-		pthread_mutex_lock(&sim_mutex);
+        sem_wait(&sim_sem);
+        int time = getTime();
 
-		//sem_wait(&sim_sem); // Wait for the thread to be allowed to start
 		// Begin going through all jobs and enqueueing them if they have arrived
 		process = in_queue->end;
 		for (int i = 0; i < in_queue->size; i++) {
-			if (process->affinity == cpu_id && process->arrival_time == TIME) {
+			if (process->affinity == cpu_id && process->arrival_time == time) {
 				// Create copy to keep the queues separate
 				Process *copy = createProcess(process->username, process->job, process->arrival_time, process->duration, process->affinity);
 				enqueue(sim_queue, copy);
@@ -156,7 +169,8 @@ void *simulation(void *args) {
 		process = sim_queue->end;
 		if (sim_queue->size == 0) { //If there is nothing in sim_queue, put '-' in the print buffer
 			print_buffer[cpu_id] = '-';
-			if (addedJobs == in_queue->size) {
+			if (addedJobs >= numberOfJobsForThisCPU) {
+
 				break; // If all jobs have been added, and the simulation queue is empty, then we are done
 			}
 		} else {
@@ -165,7 +179,7 @@ void *simulation(void *args) {
 			quantum--;
 			if (process->duration == 0) { // If the process is done, delete it
 				Process *temp = dequeue(sim_queue); // Store the process in a temp variable for deletion
-				search(summary_queue, temp->username)->finish_time = TIME; // Set the finish time for the summary queue
+				search(summary_queue, temp->username)->finish_time = time; // Set the finish time for the summary queue
 				destroyProcess(temp); // This should be called on every process
 				quantum = QUANTUM; // Make sure to reset the quantum when a process is done
 			} else if (quantum == 0) { // If the quantum is 0, then we need to dequeue the process and enqueue it again
@@ -175,8 +189,7 @@ void *simulation(void *args) {
 			}
 		}
 		// Allow the print thread to print
-		//sem_post(&print_sem);
-		pthread_mutex_unlock(&sim_mutex);
+		sem_post(&print_sem);
 	}
 	// Free memory for the simulation queue. There should be nothing left in it
 	stop(sim_queue);
@@ -185,7 +198,8 @@ void *simulation(void *args) {
 	pthread_mutex_lock(&finish_mutex);
 	finish_count++;
 	pthread_mutex_unlock(&finish_mutex);
-
+    // Allow the print thread to print one last time
+    sem_post(&print_sem);
 	return NULL;
 }
 
@@ -195,10 +209,10 @@ int main() {
 	Queue *in_queue = input_queue(); // Create the input queue
 
 	// Make sure sem is init right after getting cpus, which is done in input_queue
-	//sem_init(&sim_sem, 0, CPUS); // Initialize the semaphore
-	//sem_init(&print_sem, 0, 0); // Initialize the semaphore
+	sem_init(&print_sem, 0, 0); // Initialize the semaphore
+    sem_init(&sim_sem, 0, CPUS); // Initialize the semaphore
 	pthread_mutex_init(&finish_mutex, NULL);    // Initialize the mutex
-	pthread_mutex_init(&sim_mutex, NULL);    // Initialize the mutex
+    pthread_mutex_init(&time_mutex, NULL);    // Initialize the mutex
 
 	Queue *summary_queue = createQueue(); // Create the summary queue
 	char *print_buffer = malloc(sizeof(char) * CPUS); // Create the print buffer