X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;ds=inline;f=src%2Fthreads%2Fthread.c;h=8d9f33558bb5313b1e137250479b5103a88db689;hb=17102846d22591590c37548f8514067e2be6c5f6;hp=01e8ea42919913a8c5219221c01f52a38f5f1d3e;hpb=8abbb333aea445641d967befd3ca477502ea770b;p=pintos-anon

diff --git a/src/threads/thread.c b/src/threads/thread.c
index 01e8ea4..8d9f335 100644
--- a/src/threads/thread.c
+++ b/src/threads/thread.c
@@ -7,10 +7,10 @@
 #include "threads/flags.h"
 #include "threads/interrupt.h"
 #include "threads/intr-stubs.h"
-#include "threads/mmu.h"
 #include "threads/palloc.h"
 #include "threads/switch.h"
 #include "threads/synch.h"
+#include "threads/vaddr.h"
 #ifdef USERPROG
 #include "userprog/process.h"
 #endif
@@ -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);
     }
 }