From mboxrd@z Thu Jan  1 00:00:00 1970
From: Luiz Capitulino <lcapitulino@redhat.com>
Subject: Re: [RFC] kvm: x86: export vCPU halted state to sysfs
Date: Tue, 6 Feb 2018 09:05:19 -0500
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Cc: Eduardo Habkost <ehabkost@redhat.com>,
        Radim =?UTF-8?B?S3LEjW3DocWZ?= <rkrcmar@redhat.com>,
        kvm@vger.kernel.org, pbonzini@redhat.com, berrange@redhat.com,
        Peter Krempa <pkrempa@redhat.com>,
        John Ferlan <jferlan@redhat.com>, libvir-list@redhat.com,
        Christian Borntraeger <borntraeger@de.ibm.com>
To: Viktor Mihajlovski <mihajlov@linux.vnet.ibm.com>
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On Tue, 6 Feb 2018 11:29:46 +0100
Viktor Mihajlovski <mihajlov@linux.vnet.ibm.com> wrote:

> On 01.02.2018 21:26, Eduardo Habkost wrote:
> > On Thu, Feb 01, 2018 at 09:15:15PM +0100, Radim Krčmář wrote:  
> >> 2018-02-01 12:54-0500, Luiz Capitulino:  
> >>>
> >>> Libvirt needs to know when a vCPU is halted. To get this information,  
> >>
> >> I don't see why upper level management should care about that, a single
> >> bit about halted state that can be incorrect at the time it is processed
> >> seems of very limited use.  
> > 
> > I don't see why, either.
> > 
> > I'm CCing libvir-list and the people involved in the code that
> > added halt state to libvirt domain statistics.
> >   
> I've posted a libvirt patch to disable query-cpus in the domain stats
> collection for all architectures other than s390. This should alleviate
> the problem until we have a better method to obtain arch-specific cpu state.

This is cool, thanks a lot.

Btw, I'll follow up this week with a replacement for qemu-cpus in QEMU.
Then we can discuss again the best long term strategy for this issue.