Re: [PATCH 03/11] perf kvm: guest userspace samples should not belumped with host uspace

From: Jiri Olsa
Date: Wed Jul 25 2012 - 08:13:31 EST


On Fri, Jul 20, 2012 at 05:25:48PM -0600, David Ahern wrote:
> e.g., perf kvm --host --guest report -i perf.data --stdio -D
> shows:
>
> 1 599127912065356 0x143b8 [0x48]: PERF_RECORD_SAMPLE(IP, 5): 5671/5676: 0x7fdf95a061c0 period: 1 addr: 0
> ... chain: nr:2
> ..... 0: ffffffffffffff80
> ..... 1: fffffffffffffe00
> ... thread: qemu-kvm:5671
> ...... dso: <not found>
>
> (IP, 5) means sample in guest userspace. Those samples should not be lumped
> into the VMM's host thread. i.e, the report output:
>
> 56.86% qemu-kvm [unknown] [u] 0x00007fdf95a061c0
>
> With this patch the output emphasizes it is a guest userspace hit:
>
> 56.86% [guest/5671] [unknown] [u] 0x00007fdf95a061c0
>
> Looking at 3 VMs (2 64-bit, 1 32-bit) with each running a CPU bound
> process (openssl speed), perf report currently shows:
>
> 93.84% 117726 qemu-kvm [unknown] [u] 0x00007fd7dcaea8e5
>
> which is wrong. With this patch you get:
>
> 31.50% 39258 [guest/18772] [unknown] [u] 0x00007fd7dcaea8e5
> 31.50% 39236 [guest/11230] [unknown] [u] 0x0000000000a57340
> 30.84% 39232 [guest/18395] [unknown] [u] 0x00007f66f641e107

Tested-by: Jiri Olsa <jolsa@xxxxxxxxxx>
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