X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=src%2Fthreads%2Finit.c;h=b89b282435ffa4fd284c776049dcc4c45a60c66c;hb=0fd3a243b790dd1cfc9e0a40c57dddde56cf344d;hp=8495826da379a3624e061d3a53cc8432aa04764c;hpb=e1289bf52f9dbc8da311fe2064af85076edf82b1;p=pintos-anon

diff --git a/src/threads/init.c b/src/threads/init.c
index 8495826..b89b282 100644
--- a/src/threads/init.c
+++ b/src/threads/init.c
@@ -13,6 +13,7 @@
 #include "devices/serial.h"
 #include "devices/timer.h"
 #include "devices/vga.h"
+#include "devices/rtc.h"
 #include "threads/interrupt.h"
 #include "threads/io.h"
 #include "threads/loader.h"
@@ -41,11 +42,6 @@ size_t ram_pages;
 /* Page directory with kernel mappings only. */
 uint32_t *base_page_dir;
 
-/* -mlfqs:
-   If false (default), use round-robin scheduler.
-   If true, use multi-level feedback queue scheduler. */
-bool enable_mlfqs;
-
 #ifdef FILESYS
 /* -f: Format the file system? */
 static bool format_filesys;
@@ -76,23 +72,17 @@ main (void)
   /* Clear BSS and get machine's RAM size. */  
   ram_init ();
 
-  /* Initialize ourselves as a thread so we can use locks. */
-  thread_init ();
-
-  /* Initialize the console so we can use printf(). */
-  vga_init ();
-  serial_init_poll ();
-  console_init ();
-
-  /* Greet user. */
-  printf ("Pintos booting with %'zu kB RAM...\n", ram_pages * PGSIZE / 1024);
-
   /* Break command line into arguments and parse options. */
   argv = read_command_line ();
   argv = parse_options (argv);
 
-  /* Set random seed if parse_options() didn't. */
-  random_init (0);
+  /* Initialize ourselves as a thread so we can use locks,
+     then enable console locking. */
+  thread_init ();
+  console_init ();  
+
+  /* Greet user. */
+  printf ("Pintos booting with %'zu kB RAM...\n", ram_pages * PGSIZE / 1024);
 
   /* Initialize memory system. */
   palloc_init ();
@@ -194,7 +184,7 @@ paging_init (void)
      new page tables immediately.  See [IA32-v2a] "MOV--Move
      to/from Control Registers" and [IA32-v3a] 3.7.5 "Base Address
      of the Page Directory". */
-  asm volatile ("movl %0, %%cr3" :: "r" (vtop (base_page_dir)));
+  asm volatile ("movl %0, %%cr3" : : "r" (vtop (base_page_dir)));
 }
 
 /* Breaks the kernel command line into words and returns them as
@@ -254,7 +244,7 @@ parse_options (char **argv)
       else if (!strcmp (name, "-rs"))
         random_init (atoi (value));
       else if (!strcmp (name, "-mlfqs"))
-        enable_mlfqs = true;
+        thread_mlfqs = true;
 #ifdef USERPROG
       else if (!strcmp (name, "-ul"))
         user_page_limit = atoi (value);
@@ -262,6 +252,16 @@ parse_options (char **argv)
       else
         PANIC ("unknown option `%s' (use -h for help)", name);
     }
+
+  /* Initialize the random number generator based on the system
+     time.  This has no effect if an "-rs" option was specified.
+
+     When running under Bochs, this is not enough by itself to
+     get a good seed value, because the pintos script sets the
+     initial time to a predictable value, not to the local time,
+     for reproducibility.  To fix this, give the "-r" option to
+     the pintos script to request real-time execution. */
+  random_init (rtc_get_time ());
   
   return argv;
 }
@@ -387,7 +387,7 @@ power_off (void)
 
   for (p = s; *p != '\0'; p++)
     outb (0x8900, *p);
-  asm ("cli; hlt");
+  asm volatile ("cli; hlt" : : : "memory");
   printf ("still running...\n");
   for (;;);
 }