Redo and improve thread scheduling startup.

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

diff --git a/src/threads/init.c b/src/threads/init.c
index ae864981341d110464c59985d3ccd94e8acf193a..b099d02dd33ccbb8fb88889b821cde91ab772ad5 100644 (file)
--- a/src/threads/init.c
+++ b/src/threads/init.c
@@ -3,7 +3,6 @@
 #include <stddef.h>
 #include <limits.h>
 #include "debug.h"
-#include "gdt.h"
 #include "interrupt.h"
 #include "io.h"
 #include "kbd.h"
@@ -17,8 +16,12 @@
 #include "serial.h"
 #include "thread.h"
 #include "timer.h"
-#include "tss.h"
 #include "vga.h"
+#ifdef USERPROG
+#include "exception.h"
+#include "gdt.h"
+#include "tss.h"
+#endif
 #ifdef FILESYS
 #include "filesys.h"
 #include "disk.h"
@@ -38,10 +41,11 @@ static bool format_filesys;
 static char *initial_program;
 #endif
 
-static thread_func main_thread;
 static void ram_init (void);
 static void argv_init (void);
 
+int main (void) NO_RETURN;
+
 int
 main (void)
 {
@@ -57,10 +61,13 @@ main (void)
   argv_init ();
 
   /* Initialize memory system, segments, paging. */
+  thread_init ();
   palloc_init ();
   paging_init ();
+#ifdef USERPROG
   tss_init ();
   gdt_init ();
+#endif
   malloc_init ();
 
   /* Set random seed if not already done. */
@@ -70,29 +77,33 @@ main (void)
   intr_init ();
   timer_init ();
   kbd_init ();
+#ifdef USERPROG
+  exception_init ();
+#endif
 
-  /* Do everything else in a system thread. */
-  thread_init ();
-  thread_create ("main", main_thread, NULL);
+  /* Start thread scheduler and enable interrupts. */
   thread_start ();
-}
 
-/* Initial thread. */
-static void
-main_thread (void *aux UNUSED) 
-{
 #ifdef FILESYS
+  /* Initialize filesystem. */
   disk_init ();
   filesys_init (format_filesys);
   fsutil_run ();
 #endif
 
+  printk ("Boot complete.\n");
+
 #ifdef USERPROG
+  /* Run a user program. */
   if (initial_program != NULL)
-    thread_execute (initial_program);
-  else
-    PANIC ("no initial program specified");
+    {
+      printk ("\nExecuting '%s':\n", initial_program);
+      thread_execute (initial_program); 
+    }
 #endif
+
+  /* Terminate this thread. */
+  thread_exit ();
 }
 \f
 /* Clear BSS and obtain RAM size from loader. */
@@ -174,8 +185,9 @@ argv_init (void)
           " -p FILENAME         Print the contents of FILENAME\n"
           " -r FILENAME         Delete FILENAME\n"
           " -ls                 List the files in the filesystem\n"
-          " -D                  Dump complete filesystem contents\n");
+          " -D                  Dump complete filesystem contents\n"
 #endif
+          );
       }
     else 
       PANIC ("unknown option `%s'", argv[i]);