Remove unused and pointless bits from APIC handling code. Move some
data items into .data.read_mostly. Adjust some types.

Signed-off-by: Jan Beulich <jbeulich@xxxxxxxxxx>

--- 2011-03-09.orig/xen/arch/x86/apic.c
+++ 2011-03-09/xen/arch/x86/apic.c
@@ -64,12 +64,12 @@ static struct {
 /*
  * Knob to control our willingness to enable the local APIC.
  */
-static int enable_local_apic __initdata = 0; /* -1=force-disable, +1=force-enable */
+static s8 __initdata enable_local_apic; /* -1=force-disable, +1=force-enable */
 
 /*
  * Debug level
  */
-int apic_verbosity;
+u8 __read_mostly apic_verbosity;
 
 static bool_t __initdata opt_x2apic = 1;
 boolean_param("x2apic", opt_x2apic);
@@ -442,8 +442,6 @@ void __init sync_Arb_IDs(void)
                       | APIC_DM_INIT);
 }
 
-extern void __error_in_apic_c (void);
-
 /*
  * An initial setup of the virtual wire mode.
  */
@@ -558,8 +556,7 @@ void __devinit setup_local_APIC(void)
     value = apic_read(APIC_LVR);
     ver = GET_APIC_VERSION(value);
 
-    if ((SPURIOUS_APIC_VECTOR & 0x0f) != 0x0f)
-        __error_in_apic_c();
+    BUILD_BUG_ON((SPURIOUS_APIC_VECTOR & 0x0f) != 0x0f);
 
     /*
      * Double-check whether this APIC is really registered.
@@ -1117,12 +1114,6 @@ static void __init wait_8254_wraparound(
 }
 
 /*
- * Default initialization for 8254 timers. If we use other timers like HPET,
- * we override this later
- */
-void (*wait_timer_tick)(void) __initdata = wait_8254_wraparound;
-
-/*
  * This function sets up the local APIC timer, with a timeout of
  * 'clocks' APIC bus clock. During calibration we actually call
  * this function twice on the boot CPU, once with a bogus timeout
@@ -1204,7 +1195,7 @@ static int __init calibrate_APIC_clock(v
      * for a wraparound to start exact measurement:
      * (the current tick might have been already half done)
      */
-    wait_timer_tick();
+    wait_8254_wraparound();
 
     /*
      * We wrapped around just now. Let's start:
@@ -1217,7 +1208,7 @@ static int __init calibrate_APIC_clock(v
      * Let's wait LOOPS wraprounds:
      */
     for (i = 0; i < LOOPS; i++)
-        wait_timer_tick();
+        wait_8254_wraparound();
 
     tt2 = apic_read(APIC_TMCCT);
     if (cpu_has_tsc)
--- 2011-03-09.orig/xen/arch/x86/genapic/bigsmp.c
+++ 2011-03-09/xen/arch/x86/genapic/bigsmp.c
@@ -12,12 +12,10 @@
 #include <asm/mach-default/mach_mpparse.h>
 #include <asm/io_apic.h>
 
-static int dmi_bigsmp; /* can be set by dmi scanners */
-
 static __init int force_bigsmp(struct dmi_system_id *d)
 {
 	printk(KERN_NOTICE "%s detected: force use of apic=bigsmp\n", d->ident);
-	dmi_bigsmp = 1;
+	def_to_bigsmp = 1;
 	return 0;
 }
 
@@ -42,11 +40,9 @@ static struct dmi_system_id __initdata b
 
 static __init int probe_bigsmp(void)
 { 
-	if (def_to_bigsmp)
-		dmi_bigsmp = 1;
-	else
+	if (!def_to_bigsmp)
 		dmi_check_system(bigsmp_dmi_table);
-	return dmi_bigsmp;
+	return def_to_bigsmp;
 } 
 
 const struct genapic apic_bigsmp = {
--- 2011-03-09.orig/xen/arch/x86/genapic/probe.c
+++ 2011-03-09/xen/arch/x86/genapic/probe.c
@@ -28,7 +28,7 @@ const struct genapic *apic_probe[] __ini
 	NULL,
 };
 
-static int cmdline_apic;
+static bool_t __initdata cmdline_apic;
 
 void __init generic_bigsmp_probe(void)
 {
--- 2011-03-09.orig/xen/include/asm-x86/apic.h
+++ 2011-03-09/xen/include/asm-x86/apic.h
@@ -21,7 +21,7 @@
 #define IO_APIC_REDIR_DEST_LOGICAL	0x00800
 #define IO_APIC_REDIR_DEST_PHYSICAL	0x00000
 
-extern int apic_verbosity;
+extern u8 apic_verbosity;
 extern bool_t x2apic_enabled;
 extern bool_t directed_eoi_enabled;
 
@@ -177,8 +177,6 @@ static inline void ack_APIC_irq(void)
 	apic_write_around(APIC_EOI, 0);
 }
 
-extern void (*wait_timer_tick)(void);
-
 extern int get_maxlvt(void);
 extern void clear_local_APIC(void);
 extern void connect_bsp_APIC (void);