Re: [PATCH v1] kunit: fix failure to build without printk

[Brendan Higgins]

On Tue, Aug 27, 2019 at 1:21 PM shuah <shuah@xxxxxxxxxx> wrote:
>
> On 8/27/19 11:49 AM, Brendan Higgins wrote:
> > Previously KUnit assumed that printk would always be present, which is
> > not a valid assumption to make. Fix that by ifdefing out functions which
> > directly depend on printk core functions similar to what dev_printk
> > does.
> >
> > Reported-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
> > Link: https://lore.kernel.org/linux-kselftest/0352fae9-564f-4a97-715a-fabe016259df@xxxxxxxxxx/T/#t
> > Cc: Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx>
> > Signed-off-by: Brendan Higgins <brendanhiggins@xxxxxxxxxx>
> > ---
> >   include/kunit/test.h |  7 +++++++
> >   kunit/test.c         | 41 ++++++++++++++++++++++++-----------------
> >   2 files changed, 31 insertions(+), 17 deletions(-)
> >
> > diff --git a/include/kunit/test.h b/include/kunit/test.h
> > index 8b7eb03d4971..339af5f95c4a 100644
> > --- a/include/kunit/test.h
> > +++ b/include/kunit/test.h
> > @@ -339,9 +339,16 @@ static inline void *kunit_kzalloc(struct kunit *test, size_t size, gfp_t gfp)
[...]
> Okay after reviewing this, I am not sure why you need to do all
> this.
>
> Why can't you just change the root function that throws the warn:
>
>   static int kunit_vprintk_emit(int level, const char *fmt, va_list args)
> {
>          return vprintk_emit(0, level, NULL, 0, fmt, args);
> }
>
> You aren'r really doing anything extra here, other than calling
> vprintk_emit()

Yeah, I did that a while ago. I think it was a combination of trying
to avoid an extra layer of adding and then removing the log level, and
that's what dev_printk and friends did.

But I think you are probably right. It's a lot of maintenance overhead
to get rid of that. Probably best to just use what the printk people
have.

> Unless I am missing something, can't you solve this problem by including
> printk.h and let it handle the !CONFIG_PRINTK case?

Randy, I hope you don't mind, but I am going to ask you to re-ack my
next revision since it basically addresses the problem in a totally
different way.