Re: [Patch v3 2/2] tracing: gpio: add Kconfig option for enabling/disabling trace events

From: Linus Walleij
Date: Fri Apr 05 2019 - 13:25:34 EST


On Wed, Mar 27, 2019 at 11:12 PM Uwe Kleine-KÃnig
<u.kleine-koenig@xxxxxxxxxxxxxx> wrote:

> It happened a few times to me since this patch was merged (in 4.4-rc1)
> that I worked on a system with tracing enabled but
> /sys/kernel/debug/tracing/events/gpio were missing because of
> CONFIG_TRACING_EVENTS_GPIO=n. This is annoying and I wonder what is the
> motivating purpose of allowing to disable gpio events. There is no other
> event type that can be disabled with kconfig symbols. Theoretically the
> overhead should be so small, that having these events enabled
> unconditionally should be fine, shouldn't it?

You have a good point. We should not do anything special.

I guess by the time this was merged I believed it was customary
for trancepoints to live behind a Kconfig option.

I guess it is not.

I happily merge a patch removing this again if no case
can be made for it.

Yours,
Linus Walleij