x86, apic: Use .apicdrivers section for the apic drivers list

This will eliminate the need for apic_probe[], as the probing
now will happen based on the apic drivers order in the
.apcidrivers section.

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Tested-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: steiner@sgi.com
Cc: gorcunov@openvz.org
Cc: yinghai@kernel.org
Link: http://lkml.kernel.org/r/20110521005526.164277071@sbsiddha-MOBL3.sc.intel.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>

arch/x86/kernel/apic/probe_64.c

@@ -54,19 +54,21 @@ static int apicid_phys_pkg_id(int initial_apic_id, int index_msb)
  */
 void __init default_setup_apic_routing(void)
 {
-	int i;
+	struct apic **drv;
 
 	enable_IR_x2apic();
 
-	for (i = 0; apic_probe[i]; ++i) {
-		if (apic_probe[i]->probe()) {
-			apic = apic_probe[i];
+	for (drv = __apicdrivers; drv < __apicdrivers_end; drv++) {
+		if ((*drv)->probe && (*drv)->probe()) {
+			if (apic != *drv) {
+				apic = *drv;
+				pr_info("Switched APIC routing to %s.\n",
+					apic->name);
+			}
 			break;
 		}
 	}
 
-	printk(KERN_INFO "APIC routing finalized to %s.\n", apic->name);
-
 	if (is_vsmp_box()) {
 		/* need to update phys_pkg_id */
 		apic->phys_pkg_id = apicid_phys_pkg_id;
@@ -82,13 +84,15 @@ void apic_send_IPI_self(int vector)
 
 int __init default_acpi_madt_oem_check(char *oem_id, char *oem_table_id)
 {
-	int i;
+	struct apic **drv;
 
-	for (i = 0; apic_probe[i]; ++i) {
-		if (apic_probe[i]->acpi_madt_oem_check(oem_id, oem_table_id)) {
-			apic = apic_probe[i];
-			printk(KERN_INFO "Setting APIC routing to %s.\n",
-				apic->name);
+	for (drv = __apicdrivers; drv < __apicdrivers_end; drv++) {
+		if ((*drv)->acpi_madt_oem_check(oem_id, oem_table_id)) {
+			if (apic != *drv) {
+				apic = *drv;
+				pr_info("Setting APIC routing to %s.\n",
+					apic->name);
+			}
 			return 1;
 		}
 	}