From mboxrd@z Thu Jan  1 00:00:00 1970
From: Keir Fraser <keir.xen@gmail.com>
Subject: Re: [PATCH] Allow ACPI state change with active cpupools
Date: Tue, 20 Mar 2012 14:55:53 +0000
Message-ID: <CB8E4AF9.2ECDC%keir.xen@gmail.com>
References: <4F689847.1020709@ts.fujitsu.com>
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To: Juergen Gross <juergen.gross@ts.fujitsu.com>
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On 20/03/2012 14:46, "Juergen Gross" <juergen.gross@ts.fujitsu.com> wrote:

>> Is it better to have cpupools know about offlining/suspend, or have
>> offlining/suspend know about cpupools? I would have thought the latter makes
>> more sense since it is offlining/suspend which calls into the cpupool
>> subsystem.
> 
> I thought of a more relaxed solution in the cpupool coding:
> 
> Instead of allowing to offline a cpu only if it is in Pool-0, I would allow it
> if:
> - the cpu is not the last one in the cpupool
> - or no domain is active in the cpupool (this would include the suspend case,
>    where all domains are paused)
> 
> Together with your proposal to remember the cpupool for an offlined cpu to add
> it again when it is onlined the handling should be rather simple and local.

Ah, I see. Yes, a more flexible policy like this in the cpupool subsystem is
best solution of all, imo.

 -- Keir