diff --git a/src/threads/synch.c b/src/threads/synch.c
index 4ec2266..73dceba 100644
--- a/src/threads/synch.c
+++ b/src/threads/synch.c
@@ -413,8 +413,7 @@ cond_wait (struct condition *cond, struct lock *lock)
   ASSERT (lock_held_by_current_thread (lock));
   
   sema_init (&waiter.semaphore, 0);
-  list_insert_ordered (&cond->waiters, &waiter.elem, sema_priority_more,
-                       &thread_current ()->elem);
+  list_push_back (&cond->waiters, &waiter.elem);
   lock_release (lock);
   sema_down (&waiter.semaphore);
   lock_acquire (lock);
@@ -435,9 +434,13 @@ cond_signal (struct condition *cond, struct lock *lock UNUSED)
   ASSERT (!intr_context ());
   ASSERT (lock_held_by_current_thread (lock));
 
-  if (!list_empty (&cond->waiters)) 
-    sema_up (&list_entry (list_pop_front (&cond->waiters),
-                          struct semaphore_elem, elem)->semaphore);
+  if (!list_empty (&cond->waiters))
+    {
+      struct list_elem *e = list_min (&cond->waiters, sema_priority_more, NULL);
+      list_remove (e);
+      sema_up (&list_entry (e, struct semaphore_elem, elem)->semaphore);
+    }
+
 }
 
 /* Wakes up all threads, if any, waiting on COND (protected by