[PATCH v3 0/4] add anon mTHP collapse test cases

This patchset is split from the previous shmem mTHP collapse patchset[1],
which only adds anon mTHP collapse selftests. All khugepaged test cases
can pass.

[1] https://lore.kernel.org/all/[email protected]/

Changes from v2:
 - Collect reviewed/tested tags from Nico, Zi and Kiryl. Thanks.
 - Change check_huge_anon/shmem/file()'s parameter type to 'size_t'
   and rename to 'len' (per Zi).
 - Use safe type to calculate the order (per Zi).
 - Check return value for read_pmd_pagesize() (per Zi).
 - Add more usage() info to indicate that mthp_khugepaged currently
   only supports anonymous folios (per Zi).
 - Other minor coding style changes (per Zi).

Changes from v1:
- Add order and hpage_size check (per Sashiko).
- Change to use THP_MADVISE for mTHP collapse (per Sashiko).

Baolin Wang (4):
  selftests: mm: extend the check_huge() to support mTHP check
  selftests: mm: move gather_after_split_folio_orders() into vm_util.c
    file
  selftests: mm: implement the mTHP-sized hugepage check helpers
  selftests: mm: add mTHP collapse test cases

 .../selftests/mm/folio_split_race_test.c      |   2 +-
 tools/testing/selftests/mm/khugepaged.c       | 197 +++++++++++++----
 tools/testing/selftests/mm/pagemap_ioctl.c    |   2 +-
 .../testing/selftests/mm/prctl_thp_disable.c  |   2 +-
 tools/testing/selftests/mm/run_vmtests.sh     |   2 +
 tools/testing/selftests/mm/soft-dirty.c       |   2 +-
 .../selftests/mm/split_huge_page_test.c       | 139 +-----------
 tools/testing/selftests/mm/uffd-common.c      |   4 +-
 tools/testing/selftests/mm/vm_util.c          | 201 +++++++++++++++++-
 tools/testing/selftests/mm/vm_util.h          |   8 +-
 10 files changed, 367 insertions(+), 192 deletions(-)

-- 
2.47.3