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SubjectRe: Shouldn't kconfig defaults match recommendations in help text?
Jesper Juhl writes:
> [quote]
> The processor's performance-monitoring counters are special-purpose
> global registers. This option adds support for virtual per-process
> performance-monitoring counters which only run when the process
> to which they belong is executing. This improves the accuracy of
> performance measurements by reducing "noise" from other processes.
> Say Y.
> Virtual performance counters support (PERFCTR_VIRTUAL) [N/y/?] (NEW)
> [/quote]
> I just picked the above randomly, there are several other cases like it.
> The comment clearly makes a recommendation that the user enables (in this
> case) the option, yet the default is the exact opposite. What is the point
> in that?
> I don't see anything but confusion amongst users as the result of such
> inconsistency.

This particular mismatch occurs because the Kconfig entry
doesn't have a "default" line, so Kconfig defaults to "n".

It makes little sense to disable PERFCTR_VIRTUAL when
PERFCTR is enabled, so providing a "default y" for
PERFCTR_VIRTUAL is the right thing to do.
(It's an option because the design allows several
independent high-level services on top of the low-level
code. Currently there's only one high-level service in
2.6-mm, but with several it's reasonable to allow users
to enable only those they actually want.)

> Would patches to change default configuration choices to match the
> recommendation given in the help text (if any) be acceptable? If not I'd
> be interrested in the reasons why not.
> If such patches are acceptable/wanted I'll be happy to supply them.

Feel free to do so :-)

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