X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=src%2Fthreads%2Fthread.c;h=1b56f98508e16922de88d299cf02ec2f6f0a22f1;hb=fcf89ebe9fe61d0a1739bd48b7dd90905aab461d;hp=52f0f8d4fc73d8f65818163aaca9c7229cf8e97e;hpb=b413e78bacc4a0331191e581cd060281ba47c54a;p=pintos-anon

diff --git a/src/threads/thread.c b/src/threads/thread.c
index 52f0f8d..1b56f98 100644
--- a/src/threads/thread.c
+++ b/src/threads/thread.c
@@ -1,15 +1,15 @@
-#include "thread.h"
+#include "threads/thread.h"
+#include <debug.h>
 #include <stddef.h>
-#include "debug.h"
-#include "interrupt.h"
-#include "intr-stubs.h"
-#include "lib.h"
-#include "mmu.h"
-#include "palloc.h"
-#include "random.h"
-#include "switch.h"
+#include <random.h>
+#include <string.h>
+#include "threads/interrupt.h"
+#include "threads/intr-stubs.h"
+#include "threads/mmu.h"
+#include "threads/palloc.h"
+#include "threads/switch.h"
 #ifdef USERPROG
-#include "gdt.h"
+#include "userprog/gdt.h"
 #endif
 
 /* Value for struct thread's `magic' member.
@@ -19,12 +19,16 @@
 
 /* List of processes in THREAD_READY state, that is, processes
    that are ready to run but not actually running. */
-static struct list run_queue;
+static struct list ready_list;
 
 /* Idle thread. */
 static struct thread *idle_thread;      /* Thread. */
 static void idle (void *aux UNUSED);    /* Thread function. */
 
+/* Initial thread.
+   This is the thread running main(). */
+static struct thread *initial_thread;
+
 /* Stack frame for kernel_thread(). */
 struct kernel_thread_frame 
   {
@@ -57,17 +61,15 @@ void schedule_tail (struct thread *prev);
 void
 thread_init (void) 
 {
-  struct thread *t;
-  
   ASSERT (intr_get_level () == INTR_OFF);
 
   /* Set up a thread structure for the running thread. */
-  t = running_thread ();
-  init_thread (t, "main");
-  t->status = THREAD_RUNNING;
+  initial_thread = running_thread ();
+  init_thread (initial_thread, "main");
+  initial_thread->status = THREAD_RUNNING;
 
   /* Initialize run queue. */
-  list_init (&run_queue);
+  list_init (&ready_list);
 }
 
 /* Starts preemptive thread scheduling by enabling interrupts.
@@ -182,7 +184,7 @@ thread_unblock (struct thread *t)
   old_level = intr_disable ();
   if (t->status == THREAD_BLOCKED) 
     {
-      list_push_back (&run_queue, &t->rq_elem);
+      list_push_back (&ready_list, &t->elem);
       t->status = THREAD_READY;
     }
   intr_set_level (old_level);
@@ -241,7 +243,7 @@ thread_yield (void)
   ASSERT (!intr_context ());
 
   old_level = intr_disable ();
-  list_push_back (&run_queue, &cur->rq_elem);
+  list_push_back (&ready_list, &cur->elem);
   cur->status = THREAD_READY;
   schedule ();
   intr_set_level (old_level);
@@ -361,10 +363,10 @@ alloc_frame (struct thread *t, size_t size)
 static struct thread *
 next_thread_to_run (void) 
 {
-  if (list_empty (&run_queue))
+  if (list_empty (&ready_list))
     return idle_thread;
   else
-    return list_entry (list_pop_front (&run_queue), struct thread, rq_elem);
+    return list_entry (list_pop_front (&ready_list), struct thread, elem);
 }
 
 /* Destroys T, which must be in the dying state and must not be
@@ -379,7 +381,8 @@ destroy_thread (struct thread *t)
 #ifdef USERPROG
   addrspace_destroy (t);
 #endif
-  palloc_free (t);
+  if (t != initial_thread)
+    palloc_free (t);
 }
 
 /* Completes a thread switch by activating the new thread's page