powerpc: Disable SPARSE_IRQ by default
The SPARSE_IRQ considerably adds overhead to critical path of IRQ
handling. However it doesn't benefit much in space for most systems with
limited IRQ_NR. Should be disabled unless really necessary.
Signed-off-by: Li Yang <leoli@freescale.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 328774b..6506bf4 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -400,7 +400,7 @@
config SPARSE_IRQ
bool "Support sparse irq numbering"
- default y
+ default n
help
This enables support for sparse irqs. This is useful for distro
kernels that want to define a high CONFIG_NR_CPUS value but still
@@ -409,7 +409,7 @@
( Sparse IRQs can also be beneficial on NUMA boxes, as they spread
out the irq_desc[] array in a more NUMA-friendly way. )
- If you don't know what to do here, say Y.
+ If you don't know what to do here, say N.
config NUMA
bool "NUMA support"