From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from az33egw02.freescale.net (az33egw02.freescale.net [192.88.158.103]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "az33egw02.freescale.net", Issuer "Thawte Premium Server CA" (verified OK)) by ozlabs.org (Postfix) with ESMTPS id E4DA8B6EFE for ; Tue, 29 Jun 2010 18:50:20 +1000 (EST) Received: from az33smr01.freescale.net (az33smr01.freescale.net [10.64.34.199]) by az33egw02.freescale.net (8.14.3/az33egw02) with ESMTP id o5T8oHCs005680 for ; Tue, 29 Jun 2010 01:50:17 -0700 (MST) Received: from zch01exm26.fsl.freescale.net (zch01exm26.ap.freescale.net [10.192.129.221]) by az33smr01.freescale.net (8.13.1/8.13.0) with ESMTP id o5T90V0r015315 for ; Tue, 29 Jun 2010 04:00:32 -0500 (CDT) From: Li Yang To: benh@kernel.crashing.org, linuxppc-dev@lists.ozlabs.org Subject: [PATCH] powerpc: disable SPARSE_IRQ by default Date: Tue, 29 Jun 2010 17:32:57 +0800 Message-Id: <1277803977-3376-1-git-send-email-leoli@freescale.com> List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , 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 --- arch/powerpc/Kconfig | 4 ++-- 1 files changed, 2 insertions(+), 2 deletions(-) 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 IRQ_ALL_CPUS 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 @@ config SPARSE_IRQ ( 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" -- 1.6.6-rc1.GIT