[PATCH 3/8] kernel irqbalance fixes to handle IRQs with balancing disabled

[Venki Pallipadi <venkatesh.pallipadi@intel.com>]

kernel irq balance code moves IRQs around without checking whether
they are movable or not. Add those checks.

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>

Index: linux-2.6.21-tolkml/arch/i386/kernel/io_apic.c
===================================================================
--- linux-2.6.21-tolkml.orig/arch/i386/kernel/io_apic.c	2007-04-25 20:08:32.000000000 -0700
+++ linux-2.6.21-tolkml/arch/i386/kernel/io_apic.c	2007-05-07 09:54:50.000000000 -0700
@@ -446,7 +446,7 @@
 	Dprintk("Rotating IRQs among CPUs.\n");
 	for_each_online_cpu(i) {
 		for (j = 0; j < NR_IRQS; j++) {
-			if (!irq_desc[j].action)
+			if (!irq_desc[j].action || irq_balancing_disabled(j))
 				continue;
 			/* Is it a significant load ?  */
 			if (IRQ_DELTA(CPU_TO_PACKAGEINDEX(i),j) <
@@ -582,7 +582,7 @@
 	selected_irq = -1;
 	for (j = 0; j < NR_IRQS; j++) {
 		/* Is this an active IRQ? */
-		if (!irq_desc[j].action)
+		if (!irq_desc[j].action || irq_balancing_disabled(j))
 			continue;
 		if (imbalance <= IRQ_DELTA(max_loaded,j))
 			continue;
@@ -665,6 +665,9 @@
 	
 	/* push everything to CPU 0 to give us a starting point.  */
 	for (i = 0 ; i < NR_IRQS ; i++) {
+		if (irq_balancing_disabled(i))
+			continue;
+
 		irq_desc[i].pending_mask = cpumask_of_cpu(0);
 		set_pending_irq(i, cpumask_of_cpu(0));
 	}