[PATCH] - irq vector assignment

[Jack Steiner <steiner@sgi.com>]

Try to assign irqs to cpus on the correct node & fall back to global
assignment only if node-local fails. This reduces the chances of
using all of the interrupt vectors of a single cpu.

Signed-off-by: Jack Steiner <steiner@sgi.com>


---
 arch/x86/kernel/apic/io_apic.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

Index: linux/arch/x86/kernel/apic/io_apic.c
===================================================================
--- linux.orig/arch/x86/kernel/apic/io_apic.c	2010-06-24 12:58:11.658933610 -0500
+++ linux/arch/x86/kernel/apic/io_apic.c	2010-06-24 13:56:26.734380290 -0500
@@ -3259,7 +3259,9 @@ unsigned int create_irq_nr(unsigned int
 		desc_new = move_irq_desc(desc_new, node);
 		cfg_new = desc_new->chip_data;
 
-		if (__assign_irq_vector(new, cfg_new, apic->target_cpus()) == 0)
+		if (node >= 0 && __assign_irq_vector(new, cfg_new, node_to_cpumask_map[node]) == 0)
+			irq = new;
+		else if (__assign_irq_vector(new, cfg_new, apic->target_cpus()) == 0)
 			irq = new;
 		break;
 	}