[PATCH v2 0/2] selftests/mm: reuse FORCE_READ to replace "asm volatile("" : "+r" (XXX));"

[wang lian <lianux.mm@gmail.com>]

This series introduces a common FORCE_READ() macro to replace 
the cryptic asm volatile("" : "+r" (variable)); 
construct used in several mm selftests. This improves code readability and 
maintainability by removing duplicated, hard-to-understand code.

I previously sent the refactoring patch [1] as a standalone change, following a suggestion from David. 
As Andrew Morton and Wei Yang correctly pointed out, 
that patch was incomplete as it was missing the macro definition itself, 
causing build warnings. My apologies for the noise.

[1] https://lore.kernel.org/lkml/20250716123126.3851-1-lianux.mm@gmail.com/

This v2 series corrects that mistake by properly structuring the changes:
- The first patch introduces the FORCE_READ() macro into the shared vm_util.h header 
  and includes a minor cleanup for another test.
- The second patch then uses this new macro to refactor the selftests.

changes to v2:
- collected Acked-by and Reviewed-by from  David and Lorenzo Stoakes.

wang lian (2):
  selftests/mm: refactor common code and improve test skipping in
    guard_region
  selftests/mm: reuse FORCE_READ to replace "asm volatile("" : "+r"
    (XXX));"

 tools/testing/selftests/mm/cow.c              | 30 +++++++++----------
 tools/testing/selftests/mm/guard-regions.c    |  9 +-----
 tools/testing/selftests/mm/hugetlb-madvise.c  |  5 +---
 tools/testing/selftests/mm/migration.c        | 13 ++++----
 tools/testing/selftests/mm/pagemap_ioctl.c    |  4 +--
 .../selftests/mm/split_huge_page_test.c       |  4 +--
 tools/testing/selftests/mm/vm_util.h          |  7 +++++
 7 files changed, 32 insertions(+), 40 deletions(-)

-- 
2.43.0