Re: [PATCH -tip FIXED] ftrace: add nop tracer

From: Ingo Molnar
Date: Sat Sep 20 2008 - 02:17:20 EST



* Steven Noonan <steven@xxxxxxxxxxxxxx> wrote:

> On Fri, Sep 19, 2008 at 2:23 PM, Andrew Morton
> <akpm@xxxxxxxxxxxxxxxxxxxx> wrote:
> > On Fri, 19 Sep 2008 03:06:43 -0700
> > Steven Noonan <steven@xxxxxxxxxxxxxx> wrote:
> >
> >> --- a/kernel/trace/trace.h
> >> +++ b/kernel/trace/trace.h
> >> @@ -339,6 +339,10 @@ extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
> >> extern int trace_selftest_startup_wakeup(struct tracer *trace,
> >> struct trace_array *tr);
> >> #endif
> >> +#ifdef CONFIG_NOP_TRACER
> >> +extern int trace_selftest_startup_nop(struct tracer *trace,
> >> + struct trace_array *tr);
> >> +#endif
> >> #ifdef CONFIG_CONTEXT_SWITCH_TRACER
> >> extern int trace_selftest_startup_sched_switch(struct tracer *trace,
> >> struct trace_array *tr);
> >
> > Consider omitting the ifdefs around the declarations.
> >
> > pro: the code looks nicer and is less likely to suffer build errors
> > with weird config combinations.
> >
> > con: build errors are reported at link-time rather than at compile-time.
> >
> > Personally, I think pro>con here.
> >
>
> I merely based this on one of the other tracers, so the ifdefs are
> basically copied and renamed.

yeah. Feel free to send a separate patch that implements Andrew's
clean-up suggestion. I agree that pro>con.

Ingo
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/