[LTP] [PATCH v2] include/tst_timer: Add TST_NO_LIBLTP

[Petr Vorel]

Hi all,

> Hi,
> this is a lot of unnecessary code to fix a problem that didn't exist in the
> original sched_football patch. I'd prefer one of two other solutions:
> 1) go back to using ts_delta() from the original patch
> 2) fully port the test to new LTP API

Sounds reasonable. FYI back at the time I asked Mel Gorman to investigate which
tests would be relevant and worth to move from LTP into rt-tests. In his reply,
which I put into https://github.com/linux-test-project/ltp/issues/1078, he
considered sched_football as interesting, but requiring to reimplement.
Therefore I would prefer to minimise changes (e.g. using ts_delta) to not
complicate moving test to rt-tests in the future.

Kind regards,
Petr

> On 27. 06. 24 15:34, Cyril Hrubis wrote:
> > Older compilers (gcc-4.8) are not smart enough to eliminate the
> > impossible branch with tst_brk() early enough and the sched_football
> > compilation fails due to the unresolved function.

> > Add TST_NO_LIBLTP macro that adds tst_brk_() inline implementaiont that
> > prints the message and calls abort() and make use of it in sched_football.

> > Cc: kernel-team@android.com
> > Cc: Darren Hart <darren@os.amperecomputing.com>
> > Cc: John Stultz <jstultz@google.com>
> > Signed-off-by: Cyril Hrubis <chrubis@suse.cz>
> > ---
> >   include/tst_test.h                            | 23 +++++++++++++++++++
> >   .../func/sched_football/sched_football.c      |  1 +
> >   2 files changed, 24 insertions(+)

> > diff --git a/include/tst_test.h b/include/tst_test.h
> > index 8dc20d110..9bd1b363d 100644
> > --- a/include/tst_test.h
> > +++ b/include/tst_test.h
> > @@ -648,4 +648,27 @@ int main(int argc, char *argv[])
> >   #define TST_TEST_TCONF(message)                                 \
> >           static struct tst_test test = { .tconf_msg = message  } \
> > +/*
> > + * Fallback for cases where we do not want to link against ltp library.
> > + *
> > + * This allows us for instance to use tst_timer.h without LTP library.
> > + */
> > +#ifdef TST_NO_LIBLTP
> > +__attribute__ ((format (printf, 4, 5)))
> > +inline void tst_brk_(const char *file, const int lineno, int ttype,
> > +                     const char *fmt, ...)
> > +{
> > +	va_list va;
> > +
> > +	(void) ttype;
> > +
> > +	fprintf(stderr, "%s: %i: ", file, lineno);
> > +	va_start(va, fmt);
> > +	vfprintf(stderr, fmt, va);
> > +	va_end(va);
> > +
> > +	abort();
> > +}
> > +#endif
> > +
> >   #endif	/* TST_TEST_H__ */
> > diff --git a/testcases/realtime/func/sched_football/sched_football.c b/testcases/realtime/func/sched_football/sched_football.c
> > index b6ae692af..6846978f4 100644
> > --- a/testcases/realtime/func/sched_football/sched_football.c
> > +++ b/testcases/realtime/func/sched_football/sched_football.c
> > @@ -74,6 +74,7 @@
> >   #include <librttest.h>
> >   #include <tst_atomic.h>
> >   #define TST_NO_DEFAULT_MAIN
> > +#define TST_NO_LIBLTP
> >   #include <tst_timer.h>