From mboxrd@z Thu Jan  1 00:00:00 1970
From: Marcelo Tosatti <mtosatti@redhat.com>
Subject: Re: [PATCH] kvm-vmx: add module parameter to avoid trapping HLT
 instructions (v2)
Date: Fri, 3 Dec 2010 16:10:43 -0200
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Cc: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>,
	Anthony Liguori <aliguori@us.ibm.com>, kvm@vger.kernel.org,
	Avi Kivity <avi@redhat.com>
To: Chris Wright <chrisw@sous-sol.org>
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On Fri, Dec 03, 2010 at 09:58:54AM -0800, Chris Wright wrote:
> * Srivatsa Vaddagiri (vatsa@linux.vnet.ibm.com) wrote:
> > On Fri, Dec 03, 2010 at 09:29:06AM -0800, Chris Wright wrote:
> > > That's what Marcelo's suggestion does w/out a fill thread.
> > 
> > There's one complication though even with that. How do we compute the
> > real utilization of VM (given that it will appear to be burning 100% cycles)?
> > We need to have scheduler discount the cycles burnt post halt-exit, so more
> > stuff is needed than those simple 3-4 lines!
> 
> Heh, was just about to say the same thing ;)

Probably yes. The point is, you get the same effect as with the
non-trapping hlt but without the complications on low-level VMX/SVM
code.

Even better if you can do it with fill thread idea.