[<prev] [next>] [<thread-prev] [day] [month] [year] [list]
Message-ID: <45C99D41.1010302@qumranet.com>
Date: Wed, 07 Feb 2007 11:34:57 +0200
From: Avi Kivity <avi@...ranet.com>
To: Ingo Molnar <mingo@...e.hu>
CC: Andrew Morton <akpm@...l.org>, linux-kernel@...r.kernel.org
Subject: Re: [patch] KVM, hotplug: export register_cpu_notifier
Ingo Molnar wrote:
> * Avi Kivity <avi@...ranet.com> wrote:
>
>
>>> -#ifdef CONFIG_HOTPLUG_CPU
>>> -
>>> EXPORT_SYMBOL(register_cpu_notifier);
>>>
>>> +#ifdef CONFIG_HOTPLUG_CPU
>>> +
>>> void unregister_cpu_notifier(struct notifier_block *nb)
>>> {
>>> mutex_lock(&cpu_add_remove_lock);
>>>
>>>
>> This is broken: register_cpu_notifier() is __cpuinit, which means it
>> disappears at module time if !CONFIG_CPU_HOTPLUG.
>>
>> I submitted a hackaround to Andrew some time ago with the suspend
>> patchset.
>>
>
> ok. What does your patch do - turns it into an inline? I fixed it up in
> -rt via the patch below.
>
>
yes, but only if MODULE.
> Ingo
>
> ---------------------->
> Subject: [patch] KVM: export register_cpu_notifier
> From: Ingo Molnar <mingo@...e.hu>
>
> KVM-trunk uses register_cpu_notifier() but it's not exported
> on CONFIG_HOTPLUG_CPU. Make it a nop inline.
>
> Signed-off-by: Ingo Molnar <mingo@...e.hu>
> ---
> include/linux/cpu.h | 6 +++++-
> kernel/cpu.c | 4 ----
> 2 files changed, 5 insertions(+), 5 deletions(-)
>
> Index: linux/include/linux/cpu.h
> ===================================================================
> --- linux.orig/include/linux/cpu.h
> +++ linux/include/linux/cpu.h
> @@ -49,10 +49,14 @@ struct notifier_block;
>
> #ifdef CONFIG_SMP
> /* Need to know about CPUs going up/down? */
> -extern int register_cpu_notifier(struct notifier_block *nb);
> #ifdef CONFIG_HOTPLUG_CPU
> +extern int register_cpu_notifier(struct notifier_block *nb);
> extern void unregister_cpu_notifier(struct notifier_block *nb);
> #else
> +static inline int register_cpu_notifier(struct notifier_block *nb)
> +{
> + return 0;
> +}
> static inline void unregister_cpu_notifier(struct notifier_block *nb)
> {
> }
> Index: linux/kernel/cpu.c
> ===================================================================
> --- linux.orig/kernel/cpu.c
> +++ linux/kernel/cpu.c
> @@ -63,8 +63,6 @@ void unlock_cpu_hotplug(void)
> }
> EXPORT_SYMBOL_GPL(unlock_cpu_hotplug);
>
> -#endif /* CONFIG_HOTPLUG_CPU */
> -
> /* Need to know about CPUs going up/down? */
> int __cpuinit register_cpu_notifier(struct notifier_block *nb)
> {
> @@ -75,8 +73,6 @@ int __cpuinit register_cpu_notifier(stru
> return ret;
> }
>
> -#ifdef CONFIG_HOTPLUG_CPU
> -
> EXPORT_SYMBOL(register_cpu_notifier);
>
> void unregister_cpu_notifier(struct notifier_block *nb)
>
--
Do not meddle in the internals of kernels, for they are subtle and quick to panic.
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists