Re: [Qemu-devel] What's the intended use of log.h logging?

[Daniel P. Berrange]

On Fri, Oct 16, 2015 at 01:54:40PM +0100, Peter Maydell wrote:
> On 16 October 2015 at 13:48, Paolo Bonzini <address@hidden> wrote:
> >
> >
> > On 16/10/2015 14:33, Markus Armbruster wrote:
> >>    Looks like this is basically TCG with a couple of random LOG_UNIMP
> >>    and LOG_GUEST_ERROR thrown in.  It's definitely not a general purpose
> >>    QEMU log in its current state.
> >
> > I think these could become error_report.
> 
> No; it's important not to print these unless the user really
> asked for them (especially the GUEST_ERROR) kind. Otherwise it's
> (potentially quite a lot of) unnecessary noise.
> 
> > Some others (e.g. LOG_IOPORT) can be removed.
> >
> > LOG_MMU seems to be mostly a ppc thing, could also become a tracepoint.
> >  Likewise for LOG_PCALL and perhaps LOG_INT.
> 
> It's also very useful to be able to enable whole *classes* of
> tracing (like "tell me whenever my guest OS does something dumb");
> does the tracepoint code have any support for this?

You can use globs in tracepoint names you want to enable. So if the
tracepoints have structured / well considerd name prefixes, you can
enable classses at once.


Regards,
Daniel
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