From: Gleb Natapov <gleb@redhat.com>
To: Avi Kivity <avi@redhat.com>
Cc: kvm@vger.kernel.org, mtosatti@redhat.com
Subject: Re: [PATCH] KVM: vmx: restore MSR_IA32_DEBUGCTLMSR after VMEXIT
Date: Sun, 12 Aug 2012 20:28:38 +0300 [thread overview]
Message-ID: <20120812172838.GA23287@redhat.com> (raw)
In-Reply-To: <5027B260.5060606@redhat.com>
On Sun, Aug 12, 2012 at 04:40:48PM +0300, Avi Kivity wrote:
> On 08/12/2012 04:25 PM, Gleb Natapov wrote:
>
> >> How expensive is this? We may want a follow-on patch to cache it in a
> >> per-cpu variable.
> >>
> > I have patches ready. I couldn't measure any overhead of the
> > rdmsr(MSR_IA32_DEBUGCTLMSR).
> >
>
> Do you mean while running kvm? How about just running it in a loop?
>
No, I mean running it in a loop. Loop with or without
rdmsr(MSR_IA32_DEBUGCTLMSR) takes the same time as measured by rdtsc.
--
Gleb.
next prev parent reply other threads:[~2012-08-12 17:28 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-08-12 13:12 [PATCH] KVM: vmx: restore MSR_IA32_DEBUGCTLMSR after VMEXIT Gleb Natapov
2012-08-12 13:22 ` Avi Kivity
2012-08-12 13:25 ` Gleb Natapov
2012-08-12 13:40 ` Avi Kivity
2012-08-12 17:28 ` Gleb Natapov [this message]
2012-08-13 7:55 ` Avi Kivity
2012-08-13 22:07 ` Marcelo Tosatti
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