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From: Paolo Bonzini <pbonzini@redhat.com>
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Date: Thu, 14 Jun 2018 17:40:41 +0200
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Subject: Re: [Qemu-devel] [PATCH v2 0/2] kvm: x86 CPU power management
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To: "=?UTF-8?Q?Daniel_P._Berrang=c3=a9?=" <berrange@redhat.com>, "Michael S. Tsirkin" <mst@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>, kvm@vger.kernel.org, Marcelo Tosatti <mtosatti@redhat.com>, qemu-devel@nongnu.org, Richard Henderson <rth@twiddle.net>

On 14/06/2018 10:18, Daniel P. Berrangé wrote:
> I don't think
> the -realtime flag should ever have been introduced, and we certainly
> shouldn't add more stuff under it.
> 
> "-realtime" is referring to a very specific use case, while the
> properties listed under it are all general purpose features. Real
> time guests just happen to be one possible use case, but it is
> valid to use them for non-real time guests.
> 
> IOW, I think we should just have this as an option under -cpu or
> some other *functionally* named option, not a option named after
> a specific usage scenario.

"-cpu" is certainly wrong for KVM_CAP_X86_DISABLE_EXITS. "-cpu" is a
device option, while this is about host behavior.  "-realtime"'s name is
awful, but I still think it's the best place for this option.  Maybe we
could call it "-realtime power-mgmt={host|guest}".

A separate issue is whether the same flag should control both
KVM_CAP_X86_DISABLE_EXITS and the monitor/mwait CPUID leaf.  Eduardo,
what do you think?

Paolo