From mboxrd@z Thu Jan  1 00:00:00 1970
From: Gleb Natapov <gleb@redhat.com>
Subject: Re: Performance counters in kvm?
Date: Wed, 13 Nov 2013 19:54:09 +0200
Message-ID: <20131113175409.GA2088@redhat.com>
References: <5283AE31.1000303@cs.rutgers.edu>
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Cc: kvm@vger.kernel.org
To: "Binh Q. Pham" <binhpham@cs.rutgers.edu>
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On Wed, Nov 13, 2013 at 11:52:01AM -0500, Binh Q. Pham wrote:
> Hi all,
> 
> I just started using kvm and want to use linux 'perf' tool inside
> the virtual machine to get some information about the hardware
> performance counters. I noticed in kvm source, there is pmu.c and
> pmu-stubs.c, so I assume they provide support for PMU. However, when
> I ran 'perf stat' in the VM, all hardware events are not supported.
> Sample screen shot:
> 
> perf stat /bin/ls
> Performance counter stats for '/bin/ls':
> <not supported> cycles
> <not supported> stalled-cycles-frontend
> ....
> 
> Could someone clarify for me if I can use 'perf' in VM with the
> current kvm state?
> 
You need to specify host cpu type to QEMU: -cpu host.

--
			Gleb.