wip on hw4

pintos-env/pintos/threads/thread.c

@@ -332,6 +332,15 @@ thread_create (const char *name, int priority,
 
   intr_set_level (old_level);
 
+  // Update children list on parent and set parent pointer on child
+  struct thread* cur = thread_current();
+
+  ASSERT (cur != NULL);
+
+  //printf("Parent thread is: %s. Child is %s\n", cur->name, t->name);
+  list_push_back(&cur->children, &t->child_elem);
+  t->parent = cur;
+
   /* Add to run queue. */
   thread_unblock (t);
 
@@ -430,6 +439,7 @@ thread_exit (void)
   list_remove (&t->allelem);
   thread_current ()->status = THREAD_DYING;
   sema_up(&t->waiting_sem);
+  list_remove(&t->child_elem);
   schedule ();
   NOT_REACHED ();
 }
@@ -576,6 +586,7 @@ init_thread (struct thread *t, const char *name, int priority)
   t->stack = (uint8_t *) t + PGSIZE;
   sema_init(&t->waiting_sem, 0);
   t->waited_on_before = 0;
+  list_init(&t->children);
 
   if (thread_mlfqs) {
     t->nice_init = priority > 20 || priority < 20 ? 0 : priority;
@@ -717,12 +728,13 @@ schedule (void)
 struct thread *
 thread_get_by_tid (tid_t tid)
 {
+  struct list* children = &thread_current()->children;
   struct list_elem *e;
-  for (e = list_begin (&all_list);
+  for (e = list_begin (children);
-       e != list_end (&all_list);
+       e != list_end (children);
        e = list_next (e))
     {
-      struct thread *t = list_entry (e, struct thread, allelem);
+      struct thread *t = list_entry (e, struct thread, child_elem);
       if (t->tid == tid)
         return t;
     }

pintos-env/pintos/threads/thread.h

@@ -100,10 +100,16 @@ struct thread
     int nice;
     int nice_init;
     FPReal recent_cpu;
+    
     struct semaphore waiting_sem;
+    
     int exit_status;
     int waited_on_before;
     
+    struct thread* parent;
+    struct list_elem child_elem;
+    struct list children;
+
 #ifdef USERPROG
     /* Owned by userprog/process.c. */
     uint32_t *pagedir;                  /* Page directory. */

pintos-env/pintos/userprog/process.c

@@ -63,6 +63,7 @@ process_execute (const char *file_name)
   tid = thread_create (program_name, PRI_DEFAULT, start_process, fn_copy);
   if (tid == TID_ERROR)
     palloc_free_page (fn_copy); 
+
   return tid;
 }