Message-ID: <48E525A1.5080509@zytor.com>
Date: Thu, 02 Oct 2008 12:48:49 -0700
From: "H. Peter Anvin" <hpa@zytor.com>
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To: Ingo Molnar <mingo@elte.hu>
CC: Chuck Ebbert <cebbert@redhat.com>, linux-kernel@vger.kernel.org,
       Arjan van de Ven <arjan@infradead.org>,
       Thomas Gleixner <tglx@linutronix.de>, Li Zefan <lizf@cn.fujitsu.com>
Subject: Re: [patch x86/core] x86: allow number of additional hotplug CPUs
 to be set at compile time, V2
References: <20081001191945.4182d0be@redhat.com> <20081002081231.GC17695@elte.hu> <20081002153007.2e031232@redhat.com> <20081002194215.GA8078@elte.hu>
In-Reply-To: <20081002194215.GA8078@elte.hu>
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Ingo Molnar wrote:
>>
>> The default number of additional CPU IDs for hotplugging is determined 
>> by asking ACPI or mptables how many "disabled" CPUs there are in the 
>> system, but many systems get this wrong so that e.g. a uniprocessor 
>> machine gets an extra CPU allocated and never switches to single CPU 
>> mode.
>>
>> And sometimes CPU hotplugging is enabled only for suspend/hibernate 
>> anyway, so the additional CPU IDs are not wanted. Allow the number to 
>> be set to zero at compile time.
>>

Wouldn't this be better to have a runtime option?

	-hpa
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