Re: [OE-core] [PATCH] lttng-modules: Make it build when CONFIG_TRACEPOINTS is not enabled again

Bruce Ashfield
2021-08-25T13:47:30Z

On Wed, Aug 25, 2021 at 9:40 AM Peter Kjellerstedt
<peter.kjellerstedt@axis.com> wrote:
>
> > -----Original Message-----
> > From: Bruce Ashfield <bruce.ashfield@gmail.com>
> > Sent: den 25 augusti 2021 15:18
> > To: Peter Kjellerstedt <peter.kjellerstedt@axis.com>
> > Cc: Andrey Zhizhikin <andrey.z@gmail.com>; OE Core mailing list
> > <openembedded-core@lists.openembedded.org>
> > Subject: Re: [OE-core] [PATCH] lttng-modules: Make it build when
> > CONFIG_TRACEPOINTS is not enabled again
> >
> > On Wed, Aug 25, 2021 at 8:57 AM Peter Kjellerstedt
> > <peter.kjellerstedt@axis.com> wrote:
> > >
> > > > -----Original Message-----
> > > > From: Andrey Zhizhikin <andrey.z@gmail.com>
> > > > Sent: den 25 augusti 2021 12:20
> > > > To: Peter Kjellerstedt <peter.kjellerstedt@axis.com>
> > > > Cc: Bruce Ashfield <bruce.ashfield@gmail.com>; OE Core mailing list
> > > > <openembedded-core@lists.openembedded.org>
> > > > Subject: Re: [OE-core] [PATCH] lttng-modules: Make it build when
> > > > CONFIG_TRACEPOINTS is not enabled again
> > > >
> > > > Hello Peter,
> > > >
> > > > On Wed, Aug 25, 2021 at 11:41 AM Peter Kjellerstedt
> > > > <peter.kjellerstedt@axis.com> wrote:
> > > > >
> > > > > Makefile-Do-not-fail-if-CONFIG_TRACEPOINTS-is-not-en.patch was
> > updated
> > > > > with the 2.13.0 update (commit 5dad15af), but unfortunately it no
> > longer
> > > > > did what it was intended to do.
> > > > >
> > > > > Signed-off-by: Peter Kjellerstedt <peter.kjellerstedt@axis.com>
> > > > > ---
> > > > > ...fail-if-CONFIG_TRACEPOINTS-is-not-en.patch | 42 +++++++++++-----
> > ---
> > > > > 1 file changed, 25 insertions(+), 17 deletions(-)
> > > > >
> > > > > diff --git a/meta/recipes-kernel/lttng/lttng-modules/Makefile-Do-
> > not-
> > > > fail-if-CONFIG_TRACEPOINTS-is-not-en.patch b/meta/recipes-
> > > > kernel/lttng/lttng-modules/Makefile-Do-not-fail-if-CONFIG_TRACEPOINTS-
> > is-
> > > > not-en.patch
> > > >
> > > > I guess the patch you've refreshed is not a correct one...
> > > >
> > > > There is another patch introduced by Bruce in the commit 18bf7b0
> > > > ("lttng-modules: update devupstream to v2.13-rc "), namely
> > > > 0001-src-Kbuild-change-missing-CONFIG_TRACEPOINTS-to-warn.patch
> > > >
> > > > It make sense to refresh rather that one instead of the Makefile one,
> > > > and have it included in the SRC_URI (see discussion in
> > > > https://lists.openembedded.org/g/openembedded-
> > core/topic/84950303#154888).
> > > >
> > > > --
> > > > Regards,
> > > > Andrey.
> > >
> > > Right, I had missed that there were two patches doing the same thing
> > > (though neither actually solved the problem after the update to 2.13.0).
> > > I will send an updated review unifying the patches and adding my
> > solution
> > > to disable building the module when CONFIG_TRACEPOINTS is not enabled.
> > >
> >
> > We really should stop dragging these patches along at all.
> >
> > I have a unified set of patches here as well, but continuing to allow
> > lttng modules to build in configurations like these, just doesn't make
> > sense (which is why I haven't sent them).
> >
> > We should have a distro feature, and simply drop it from package lists
> > when appropriate.
> >
> > Bruce
> >
> > > //Peter
>
> I know nothing about lttng myself, but has passed on your concerns to our
> maintainer for the functionality. Unfortunately he is on vacation for a
> couple of weeks more, so I do not know when I can expect an answer from
> him.
>

No worries.

> So for now I hope we can update the recipe per my patches so that it
> continues to work as before, and then we can take the discussion of
> whether it should be possible to build lttng-modules without
> CONFIG_TRACEPOINTS enabled separately.

Agreed.

I've chucked my patches that fixed the build here as well, since they
were very similar to yours.

I'll continue creating a dummy package / distro feature option here,
since pulling those patches along is a particular pain point for me, as
I continually hit lttng issues as I work through new kernels :D

Bruce

>
> //Peter
>

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thee at its end
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