[PATCH v6 0/3] printf: convert self-test to KUnit

[Tamir Duberstein <tamird@gmail.com>]

This is one of just 3 remaining "Test Module" kselftests (the others
being bitmap and scanf), the rest having been converted to KUnit.

I tested this using:

$ tools/testing/kunit/kunit.py run --arch arm64 --make_options LLVM=1 printf

I have also sent out a series converting scanf[0].

Link: https://lore.kernel.org/all/20250204-scanf-kunit-convert-v3-0-386d7c3ee714@gmail.com/T/#u [0]

Signed-off-by: Tamir Duberstein <tamird@gmail.com>
---
Changes in v6:
- Use __printf correctly on `__test`. (Petr Mladek)
- Rebase on linux-next.
- Remove leftover references to `printf.sh`.
- Update comment in `hash_pointer`. (Petr Mladek)
- Avoid overrun in `KUNIT_EXPECT_MEMNEQ`. (Petr Mladek)
- Restore trailing newlines on printk strings and add some missing ones.
  (Petr Mladek)
- Use `kunit_skip` on not-yet-initialized crng. (Petr Mladek)
- Link to v5: https://lore.kernel.org/r/20250221-printf-kunit-convert-v5-0-5db840301730@gmail.com

Changes in v5:
- Update `do_test` `__printf` annotation (Rasmus Villemoes).
- Link to v4: https://lore.kernel.org/r/20250214-printf-kunit-convert-v4-0-c254572f1565@gmail.com

Changes in v4:
- Add patch "implicate test line in failure messages".
- Rebase on linux-next, move scanf_kunit.c into lib/tests/.
- Link to v3: https://lore.kernel.org/r/20250210-printf-kunit-convert-v3-0-ee6ac5500f5e@gmail.com

Changes in v3:
- Remove extraneous trailing newlines from failure messages.
- Replace `pr_warn` with `kunit_warn`.
- Drop arch changes.
- Remove KUnit boilerplate from CONFIG_PRINTF_KUNIT_TEST help text.
- Restore `total_tests` counting.
- Remove tc_fail macro in last patch.
- Link to v2: https://lore.kernel.org/r/20250207-printf-kunit-convert-v2-0-057b23860823@gmail.com

Changes in v2:
- Incorporate code review from prior work[0] by Arpitha Raghunandan.
- Link to v1: https://lore.kernel.org/r/20250204-printf-kunit-convert-v1-0-ecf1b846a4de@gmail.com

Link: https://lore.kernel.org/lkml/20200817043028.76502-1-98.arpi@gmail.com/t/#u [0]

---
Tamir Duberstein (3):
      printf: convert self-test to KUnit
      printf: break kunit into test cases
      printf: implicate test line in failure messages

 Documentation/core-api/printk-formats.rst   |   4 +-
 Documentation/dev-tools/kselftest.rst       |   2 +-
 MAINTAINERS                                 |   2 +-
 lib/Kconfig.debug                           |  12 +-
 lib/Makefile                                |   1 -
 lib/tests/Makefile                          |   1 +
 lib/{test_printf.c => tests/printf_kunit.c} | 442 ++++++++++++----------------
 tools/testing/selftests/kselftest/module.sh |   2 +-
 tools/testing/selftests/lib/Makefile        |   2 +-
 tools/testing/selftests/lib/config          |   1 -
 tools/testing/selftests/lib/printf.sh       |   4 -
 11 files changed, 207 insertions(+), 266 deletions(-)
---
base-commit: 7ec162622e66a4ff886f8f28712ea1b13069e1aa
change-id: 20250131-printf-kunit-convert-fd4012aa2ec6

Best regards,
-- 
Tamir Duberstein <tamird@gmail.com>