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[pintos-anon] / src / threads / thread.c

diff --git a/src/threads/thread.c b/src/threads/thread.c
index 01e8ea42919913a8c5219221c01f52a38f5f1d3e..ca8a8b07e3fa54769d2068e482a2cb019c2ef563 100644 (file)
--- a/src/threads/thread.c
+++ b/src/threads/thread.c
@@ -92,7 +92,7 @@ thread_init (void)
 void
 thread_start (void) 
 {
-  thread_create ("idle", PRI_MAX, idle, NULL);
+  thread_create ("idle", PRI_MIN, idle, NULL);
   intr_enable ();
 }
 
@@ -483,12 +483,13 @@ schedule_tail (struct thread *prev)
 
   /* If the thread we switched from is dying, destroy its struct
      thread.  This must happen late so that thread_exit() doesn't
-     pull out the rug under itself. */
-  if (prev != NULL && prev->status == THREAD_DYING) 
+     pull out the rug under itself.  (We don't free
+     initial_thread because its memory was not obtained via
+     palloc().) */
+  if (prev != NULL && prev->status == THREAD_DYING && prev != initial_thread) 
     {
       ASSERT (prev != cur);
-      if (prev != initial_thread)
-        palloc_free_page (prev);
+      palloc_free_page (prev);
     }
 }