Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932844AbXJQL1Z (ORCPT ); Wed, 17 Oct 2007 07:27:25 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1758984AbXJQL1P (ORCPT ); Wed, 17 Oct 2007 07:27:15 -0400 Received: from netops-testserver-3-out.sgi.com ([192.48.171.28]:56132 "EHLO relay.sgi.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1754652AbXJQL1O (ORCPT ); Wed, 17 Oct 2007 07:27:14 -0400 Date: Wed, 17 Oct 2007 04:27:09 -0700 From: Paul Jackson To: Paul Jackson Cc: ego@in.ibm.com, torvalds@linux-foundation.org, akpm@linux-foundation.org, linux-kernel@vger.kernel.org, vatsa@in.ibm.com, rusty@rustcorp.com.au, dipankar@in.ibm.com, oleg@tv-sign.ru, mingo@elte.hu, paulmck@us.ibm.com Subject: Re: [RFC PATCH 1/4] Refcount Based Cpu-Hotplug Implementation Message-Id: <20071017042709.02525cbd.pj@sgi.com> In-Reply-To: <20071017035327.ff1ed622.pj@sgi.com> References: <20071016103308.GA9907@in.ibm.com> <20071016103417.GA16570@in.ibm.com> <20071017035327.ff1ed622.pj@sgi.com> Organization: SGI X-Mailer: Sylpheed version 2.2.4 (GTK+ 2.8.3; i686-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2493 Lines: 77 With the following patch, the four cpu hotplug patches by Gautham R Shenoy boot successfully on my sn2_defconfig ia64 SN2 Altix system. This patch moves the cpu_hotplug_init() code outside of the #ifdef CONFIG_HOTPLUG_CPU code. I will confess to being confused however as to the best way to handle this. Having "cpu_hotplug_init" be a piece of code that has to execute whether or not CONFIG_HOTPLUG_CPU is enabled doesn't seem right. Signed-off-by: Paul Jackson --- include/linux/cpu.h | 3 +-- kernel/cpu.c | 4 ++-- 2 files changed, 3 insertions(+), 4 deletions(-) --- 2.6.23-mm1.orig/include/linux/cpu.h 2007-10-17 03:59:59.529623639 -0700 +++ 2.6.23-mm1/include/linux/cpu.h 2007-10-17 04:03:56.257223754 -0700 @@ -83,6 +83,7 @@ static inline void unregister_cpu_notifi #endif /* CONFIG_SMP */ extern struct sysdev_class cpu_sysdev_class; +extern void cpu_hotplug_init(void); #ifdef CONFIG_HOTPLUG_CPU /* Stop CPUs going up and down. */ @@ -97,7 +98,6 @@ static inline void cpuhotplug_mutex_unlo mutex_unlock(cpu_hp_mutex); } -extern void cpu_hotplug_init(void); extern void get_online_cpus(void); extern void put_online_cpus(void); #define hotcpu_notifier(fn, pri) { \ @@ -117,7 +117,6 @@ static inline void cpuhotplug_mutex_lock static inline void cpuhotplug_mutex_unlock(struct mutex *cpu_hp_mutex) { } -#define cpu_hotplug_init() do { } while (0) #define get_online_cpus() do { } while (0) #define put_online_cpus() do { } while (0) #define hotcpu_notifier(fn, pri) do { (void)(fn); } while (0) --- 2.6.23-mm1.orig/kernel/cpu.c 2007-10-17 03:59:59.873628872 -0700 +++ 2.6.23-mm1/kernel/cpu.c 2007-10-17 04:04:52.522079165 -0700 @@ -38,8 +38,6 @@ static struct { #define writer_exists() (cpu_hotplug.active_writer != NULL) -#ifdef CONFIG_HOTPLUG_CPU - void __init cpu_hotplug_init(void) { cpu_hotplug.active_writer = NULL; @@ -48,6 +46,8 @@ void __init cpu_hotplug_init(void) init_completion(&cpu_hotplug.readers_done); } +#ifdef CONFIG_HOTPLUG_CPU + void get_online_cpus(void) { might_sleep(); -- I won't rest till it's the best ... Programmer, Linux Scalability Paul Jackson 1.925.600.0401 - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/