On Tue, Feb 22, 2022 at 09:00:21AM -0500, Steven Rostedt wrote:
> On Tue, 22 Feb 2022 08:27:31 +0200
> Yordan Karadzhov <y.karadz@xxxxxxxxx> wrote:
>
> > I have one last question. Do you consider as a valid use case that
> > the library must support, someone to do a just 'test" without writing
> > after this, or to "write" without testing first?
>
> Actually, that's a very good point.
>
> I was thinking that I didn't like the "test" name, and was thinking of
> having it be:
>
> if (tracefs_user_event_enabled(event)) {
> tracefs_user_event_record(event, ...);
> }
I do like the renaming of test to enabled and write to record.
>
> But I think you have a good point. Perhaps we should just have:
>
> tracefs_user_event_trace(event, ...);
>
> and it do all the work. But it would need to be a macro, that does:
>
> #define tracefs_user_event_trace(event, ...) \
> do { \
> if (tracefs_user_event_enabled(event)) { \
> tracefs_user_event_record(event, ##__VA_ARGS); \
> } \
> } while (0)
>
> Because we do not want to have the compiler process the arguments when
> the event is not enabled. That would be too much overhead.
>
> But as a macro, it would work.
>
> Thoughts?
Many times we have found that we have to do work that should only be
performed if the event is enabled. As long as there is a still clear
ways to check without the macro, this would be fine with me.
IE: strlen(message)
We should not walk strings unless the event is enabled.
Thanks,
-Beau
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