Re: trace/events: DECLARE vs DEFINE semantic

From: Mathieu Desnoyers
Date: Wed Dec 02 2009 - 18:20:41 EST


* H. Peter Anvin (hpa@xxxxxxxxx) wrote:
> On 12/02/2009 02:57 PM, Mathieu Desnoyers wrote:
> >>
> >> TRACE_CLASS - Declares a class
> >> TRACE_CLASS_EVENT - defines an event for said class
> >> TRACE_EVENT - Declares a class and defines an event (as is today)
> >
> > Yep, it looks good! It's self-descriptive and don't require to explain
> > what the thing is doing each time we refer to it. (however I feel a bit
> > sad for Fred, Wilma and Barney) ;)
> >
>
> Although you have to admit it's a bit confusing that:
>
> TRACE_EVENT = TRACE_CLASS + TRACE_CLASS_EVENT
>
> ... as opposed to ...
>
> TRACE_CLASS_EVENT = TRACE_CLASS + TRACE_EVENT
>
> -hpa

Then I would say that TRACE_EVENT should probably not have the
side-effect of declaring a globally-reuseable class. Maybe under the
hood it could create a privately-named class, but I don't see how it can
be re-used by following TRACE_CLASS_EVENT without causing confusion.

I'd go for:

TRACE_CLASS - Declares/defines a class
TRACE_CLASS_EVENT - Declares/defines an event for said class
TRACE_EVENT - Declares/defines a private class and declares/defines an event

Mathieu



>
> --
> H. Peter Anvin, Intel Open Source Technology Center
> I work for Intel. I don't speak on their behalf.
>

--
Mathieu Desnoyers
OpenPGP key fingerprint: 8CD5 52C3 8E3C 4140 715F BA06 3F25 A8FE 3BAE 9A68
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