[PATCH v3 54/68] selftests/rseq: Drop define _GNU_SOURCE

[Edward Liaw]

On Thu, May 9, 2024 at 1:16 PM Mathieu Desnoyers
<mathieu.desnoyers at efficios.com> wrote:
>
> On 2024-05-09 15:58, Edward Liaw wrote:
> > _GNU_SOURCE is provided by lib.mk, so it should be dropped to prevent
> > redefinition warnings.
> >
> > Fixes: 809216233555 ("selftests/harness: remove use of LINE_MAX")
>
> The patch per se looks fine, except for the "Fixes" tag.
>
> Commit 809216233555 introduces use of asprintf in kselftest_harness.h
> which is used by (all ?) selftests, including the rseq ones. However,
> the rseq selftests each have the #define _GNU_SOURCE, which would have
> been OK without those further changes.
>
> So this patch is more about consolidating where the _GNU_SOURCE is
> defined, which is OK with me, but not so much about "fixing" an
> issue with commit 809216233555.
>
> A "Fix" is something to be backported to stable kernels, and I
> don't think this patch reaches that threshold.
>
> If anything, this patch removes a warning that gets added by
> https://lore.kernel.org/lkml/20240509200022.253089-1-edliaw@google.com/T/#mf8438d03de6e2b613da4f86d4f60c5fe1c5f8483
> within the same series.
>
> Arguably, each #define _GNU_SOURCE could have been first protected
> by a #ifndef guard to eliminate this transient warning, and there
> would be nothing to "fix" in this consolidation series.

That makes sense.  I can remove the fixes tags.  809216233555 will
likely be reverted first anyway, and you're right that the focus of
this patch series is on consolidating _GNU_SOURCE.


>
> Thoughts ?
>
> Thanks,
>
> Mathieu
>
> > Reviewed-by: John Hubbard <jhubbard at nvidia.com>
> > Reviewed-by: Muhammad Usama Anjum <usama.anjum at collabora.com>
> > Signed-off-by: Edward Liaw <edliaw at google.com>
> > ---
> >   tools/testing/selftests/rseq/basic_percpu_ops_test.c | 1 -
> >   tools/testing/selftests/rseq/basic_test.c            | 2 --
> >   tools/testing/selftests/rseq/param_test.c            | 1 -
> >   tools/testing/selftests/rseq/rseq.c                  | 2 --
> >   4 files changed, 6 deletions(-)
> >
> > diff --git a/tools/testing/selftests/rseq/basic_percpu_ops_test.c b/tools/testing/selftests/rseq/basic_percpu_ops_test.c
> > index 2348d2c20d0a..5961c24ee1ae 100644
> > --- a/tools/testing/selftests/rseq/basic_percpu_ops_test.c
> > +++ b/tools/testing/selftests/rseq/basic_percpu_ops_test.c
> > @@ -1,5 +1,4 @@
> >   // SPDX-License-Identifier: LGPL-2.1
> > -#define _GNU_SOURCE
> >   #include <assert.h>
> >   #include <pthread.h>
> >   #include <sched.h>
> > diff --git a/tools/testing/selftests/rseq/basic_test.c b/tools/testing/selftests/rseq/basic_test.c
> > index 295eea16466f..1fed749b4bd7 100644
> > --- a/tools/testing/selftests/rseq/basic_test.c
> > +++ b/tools/testing/selftests/rseq/basic_test.c
> > @@ -2,8 +2,6 @@
> >   /*
> >    * Basic test coverage for critical regions and rseq_current_cpu().
> >    */
> > -
> > -#define _GNU_SOURCE
> >   #include <assert.h>
> >   #include <sched.h>
> >   #include <signal.h>
> > diff --git a/tools/testing/selftests/rseq/param_test.c b/tools/testing/selftests/rseq/param_test.c
> > index 2f37961240ca..48a55d94eb72 100644
> > --- a/tools/testing/selftests/rseq/param_test.c
> > +++ b/tools/testing/selftests/rseq/param_test.c
> > @@ -1,5 +1,4 @@
> >   // SPDX-License-Identifier: LGPL-2.1
> > -#define _GNU_SOURCE
> >   #include <assert.h>
> >   #include <linux/membarrier.h>
> >   #include <pthread.h>
> > diff --git a/tools/testing/selftests/rseq/rseq.c b/tools/testing/selftests/rseq/rseq.c
> > index 96e812bdf8a4..88602889414c 100644
> > --- a/tools/testing/selftests/rseq/rseq.c
> > +++ b/tools/testing/selftests/rseq/rseq.c
> > @@ -14,8 +14,6 @@
> >    * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
> >    * Lesser General Public License for more details.
> >    */
> > -
> > -#define _GNU_SOURCE
> >   #include <errno.h>
> >   #include <sched.h>
> >   #include <stdio.h>
>
> --
> Mathieu Desnoyers
> EfficiOS Inc.
> https://www.efficios.com
>