Re: [RFC PATCH 0/2] kvm/vmx: Output TSC offset

David Sharp
2012-11-14T02:03:03Z

On Tue, Nov 13, 2012 at 6:00 PM, Steven Rostedt <rostedt@goodmis.org> wrote:
> On Wed, 2012-11-14 at 10:36 +0900, Yoshihiro YUNOMAE wrote:
>
>> To merge the data like previous pattern, we apply this patch set. Then, we can
>> get TSC offset of the guest as follows:
>>
>> $ dmesg | grep kvm
>> [ 57.717180] kvm: (2687) write TSC offset 18446743360465545001, now clock ##
>> ^^^^ ^^^^^^^^^^^^^^^^^^^^ |
>> PID TSC offset |
>> HOST TSC value --+
>>
>
> Using printk to export something like this is IMO a nasty hack.
>
> Can't we create a /sys or /proc file to export the same thing?

Since the value changes over the course of the trace, and seems to be
part of the context of the trace, I think I'd include it as a
tracepoint.

>
> -- Steve
>
>