Re: kvmmmu tracing

Johannes Berg
2009-11-23T15:46:43Z

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On Mon, 2009-11-23 at 09:58 -0500, Steven Rostedt wrote:
> On Mon, 2009-11-23 at 12:06 +0100, Johannes Berg wrote:
> > Commit f691fe1da7e2715137d21ae5a80bec64db4625db is really broken wrt.
> > the userspace interface for tracing because of the weird
> > KVM_MMU_PAGE_PRINTK macro.
> >
> > Maybe we should have a "unsafe for export" flag for events, if they do
> > strange things like that?
> >
> > As it stands, I can't use trace-cmd on an x86 machine that has kvm
> > enabled because it will try to read all the kvm stuff. Arguably, it
> > should only try to parse it when it needs it (i.e. not for me) but still
> > it's very inconvenient to export something to userspace that it cannot
> > possibly understand.
>
> Note, I updated trace-cmd. I still does not read this macro nicely, but
> it at least does not fail anymore.

Ah, good to know. So I guess I don't care any more since I'm not
actually tracing this. However, since trace-cmd is very convenient for
record + send-by-email + report/analyse, it might make sense to fix
anyway.