From mboxrd@z Thu Jan  1 00:00:00 1970
From: Peter Zijlstra <a.p.zijlstra@chello.nl>
Subject: Re: [PATCH v2 8/9] KVM, VMX: Add support for guest/host-only
 profiling
Date: Wed, 05 Oct 2011 17:34:49 +0200
Message-ID: <1317828889.6766.38.camel@twins>
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	 <1317816084-18026-9-git-send-email-gleb@redhat.com>
	 <1317824379.6766.30.camel@twins> <20111005152954.GL30105@redhat.com>
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Cc: linux-kernel@vger.kernel.org, avi@redhat.com, kvm@vger.kernel.org,
	joerg.roedel@amd.com, mingo@elte.hu,
	Frederic Weisbecker <fweisbec@gmail.com>
To: Gleb Natapov <gleb@redhat.com>
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On Wed, 2011-10-05 at 17:29 +0200, Gleb Natapov wrote:
> On Wed, Oct 05, 2011 at 04:19:39PM +0200, Peter Zijlstra wrote:
> > On Wed, 2011-10-05 at 14:01 +0200, Gleb Natapov wrote:
> > > +static void atomic_switch_perf_msrs(struct vcpu_vmx *vmx)
> > > +{
> > > +       int i, nr_msrs;
> > > +       struct perf_guest_switch_msr *msrs;
> > > +
> > > +       msrs = perf_guest_get_msrs(&nr_msrs);
> > > +
> > > +       if (!msrs)
> > > +               return;
> > > +
> > > +       for (i = 0; i < nr_msrs; i++)
> > > +               if (msrs[i].host == msrs[i].guest)
> > > +                       clear_atomic_switch_msr(vmx, msrs[i].msr);
> > > +               else
> > > +                       add_atomic_switch_msr(vmx, msrs[i].msr, msrs[i].guest,
> > > +                                       msrs[i].host);
> > > +} 
> > 
> > I don't think this will actually compile with PERF_EVENTS=n due to
> > struct perf_guest_switch_msr not being defined.
> Oops you are right. Turns out it is not enough to remove PERF_EVENTS
> from .config to disable it. It re-appears after "make oldconfig". Should
> I send incremental patch to fix that?

Frederic, what's the status of being able to disable PERF on x86 again?