Re: [Qemu-devel] [RFC PATCH 0/6] virtio-trace: Support virtio-trace

[Stefan Hajnoczi]

On Wed, Jul 25, 2012 at 10:13 AM, Yoshihiro YUNOMAE
<address@hidden> wrote:
> Hi Stefan,
>
>
> (2012/07/24 22:41), Stefan Hajnoczi wrote:
>>
>> On Tue, Jul 24, 2012 at 12:19 PM, Yoshihiro YUNOMAE
>> <address@hidden> wrote:
>>>>>
>>>>> Are you using text formatted ftrace?
>>>
>>> No, currently using raw format, but　we'd like to reformat it in text.
>>
>>
>> Capturing the info necessary to translate numbers into symbols is one
>> of the problems of host<->guest tracing so I'm curious how you handle
>> this :).
>
>
> Right, your consideration is true.
>
>
>> Apologies for my lack of ftrace knowledge but how useful is the raw
>> tracing data on the host?  How do you pretty-print it in
>> human-readable form?
>
>
> perf and trace-cmd can actually translate raw-formatted trace data to
> text-formatted trace data by using information of kernel or trace
> format under tracing/events directory in debugfs. In the same way, if
> the information of a guest is exported to a host, we can translate
> raw trace data of a guest to text trace data on a host. We will use
> 9pfs to export that.

Thanks, it's clear now :).

Stefan