From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eduardo Habkost <ehabkost@redhat.com>
Subject: Re: [PATCH v2 1/2] kvm: support -realtime cpu-pm=on|off
Date: Wed, 13 Jun 2018 17:35:52 -0300
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Cc: Paolo Bonzini <pbonzini@redhat.com>, Marcelo Tosatti <mtosatti@redhat.com>,
	qemu-devel@nongnu.org, kvm@vger.kernel.org,
	Richard Henderson <rth@twiddle.net>
To: "Michael S. Tsirkin" <mst@redhat.com>
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On Tue, Jun 12, 2018 at 09:47:11PM +0300, Michael S. Tsirkin wrote:
> With this flag, kvm allows guest to control host CPU power state.  This
> increases latency for other processes using same host CPU in an
> unpredictable way, but if decreases idle entry/exit times for the
> running VCPU.
> 
> Follow-up patches will expose this capability to guest
> (using mwait leaf).
> 
> Based on a patch by Wanpeng Li <kernellwp@gmail.com> .
> 
> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

The interface makes sense to me, but:

> +extern bool enable_cpu_pm;

Why do we need a global variable if initialization code can call
qemu_opt_get_bool() directly?

-- 
Eduardo