x86_64: rename irq_desc/irq_desc_alloc

change names:

          irq_desc() ==> irq_desc_alloc
	__irq_desc() ==> irq_desc

Also split a few of the uses in lowlevel x86 code.

v2: need to check if desc is null in smp_irq_move_cleanup

Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c
index a4bb0da9..9fc5e69 100644
--- a/kernel/irq/chip.c
+++ b/kernel/irq/chip.c
@@ -27,7 +27,8 @@
 	struct irq_desc *desc;
 	unsigned long flags;
 
-	desc = irq_to_desc(irq);
+	/* first time to use this irq_desc */
+	desc = irq_to_desc_alloc(irq);
 	if (!desc) {
 		WARN(1, KERN_ERR "Trying to initialize invalid IRQ%d\n", irq);
 		return;
@@ -60,7 +61,7 @@
 	struct irq_desc *desc;
 	unsigned long flags;
 
-	desc = __irq_to_desc(irq);
+	desc = irq_to_desc(irq);
 	if (!desc) {
 		WARN(1, KERN_ERR "Trying to cleanup invalid IRQ%d\n", irq);
 		return;
@@ -92,7 +93,7 @@
 	struct irq_desc *desc;
 	unsigned long flags;
 
-	desc = __irq_to_desc(irq);
+	desc = irq_to_desc(irq);
 	if (!desc) {
 		WARN(1, KERN_ERR "Trying to install chip for IRQ%d\n", irq);
 		return -EINVAL;
@@ -122,7 +123,7 @@
 	unsigned long flags;
 	int ret = -ENXIO;
 
-	desc = __irq_to_desc(irq);
+	desc = irq_to_desc(irq);
 	if (!desc) {
 		printk(KERN_ERR "Trying to set irq type for IRQ%d\n", irq);
 		return -ENODEV;
@@ -150,7 +151,7 @@
 	struct irq_desc *desc;
 	unsigned long flags;
 
-	desc = __irq_to_desc(irq);
+	desc = irq_to_desc(irq);
 	if (!desc) {
 		printk(KERN_ERR
 		       "Trying to install controller data for IRQ%d\n", irq);
@@ -176,7 +177,7 @@
 	struct irq_desc *desc;
 	unsigned long flags;
 
-	desc = __irq_to_desc(irq);
+	desc = irq_to_desc(irq);
 	if (!desc) {
 		printk(KERN_ERR
 		       "Trying to install msi data for IRQ%d\n", irq);
@@ -203,7 +204,7 @@
 	struct irq_desc *desc;
 	unsigned long flags;
 
-	desc = __irq_to_desc(irq);
+	desc = irq_to_desc(irq);
 	if (!desc) {
 		printk(KERN_ERR
 		       "Trying to install chip data for IRQ%d\n", irq);
@@ -554,7 +555,7 @@
 	struct irq_desc *desc;
 	unsigned long flags;
 
-	desc = __irq_to_desc(irq);
+	desc = irq_to_desc(irq);
 	if (!desc) {
 		printk(KERN_ERR
 		       "Trying to install type control for IRQ%d\n", irq);
@@ -618,7 +619,7 @@
 	struct irq_desc *desc;
 	unsigned long flags;
 
-	desc = __irq_to_desc(irq);
+	desc = irq_to_desc(irq);
 	if (!desc) {
 		printk(KERN_ERR "Trying to mark IRQ%d non-probeable\n", irq);
 
@@ -635,7 +636,7 @@
 	struct irq_desc *desc;
 	unsigned long flags;
 
-	desc = __irq_to_desc(irq);
+	desc = irq_to_desc(irq);
 	if (!desc) {
 		printk(KERN_ERR "Trying to mark IRQ%d probeable\n", irq);