On 13 Mar 2026, at 11:15, Mike Rapoport wrote: > On Thu, Mar 12, 2026 at 10:11:12AM -0400, Zi Yan wrote: >> On 12 Mar 2026, at 7:40, Chunyu Hu wrote: >> >>> When thp is not enabled on some kernel config such as realtime kernel, the >>> test will report failure. Fix the false positive by skipping the test >>> directly when thp is not enabled. >>> >>> There's a naming conflict on write_file() function, both thp_settings.h and >>> split_huge_page_test.c define it. To make use of thp_is_enabled() helper in >>> the thp_settings.h, rename this local write_file to safe_write_file to >>> avoid the conflict. The reason to use 'safe_' is it does some error check. >> >> Both write_file() do safe checks. Actually the code of both functions looks >> almost identical except that the thp_settings one does exit() instead of >> ksft_exit_fail_msg(). >> >> Can you rename the split_huge_page_test’s write_file() to write_file_local() >> and add a comment above the function like >> /* add _local to avoid a function conflict with thp_settings.h */? > > Looks like we can move the version that uses ksft_exit_fail_msg() to > vm_util and drop the other one.
Could work. tools/testing/selftests/mm/khugepaged.c uses the write_file() from thp_settings.h in file_setup_area(), which is part of struct mem_ops. I thought struct mem_ops was passed to some syscall, but it turns out that it is used locally. The only downside is that file_setup_area() now has this ksefltest friendly code. Someone might want to clean up tools/testing/selftests/mm/khugepaged.c with kselftests APIs. :) > >> With that, feel free to add: >> >> Reviewed-by: Zi Yan <[email protected]> >> >> Thanks. >> >>> >>> Tested with thp disabled kernel: >>> Before The fix: >>> # -------------------------------------------------- >>> # running ./split_huge_page_test /tmp/xfs_dir_Ywup9p >>> # -------------------------------------------------- >>> # TAP version 13 >>> # Bail out! Reading PMD pagesize failed >>> # # Totals: pass:0 fail:0 xfail:0 xpass:0 skip:0 error:0 >>> # [FAIL] >>> not ok 61 split_huge_page_test /tmp/xfs_dir_Ywup9p # exit=1 >>> >>> After the fix: >>> # -------------------------------------------------- >>> # running ./split_huge_page_test /tmp/xfs_dir_YHPUPl >>> # -------------------------------------------------- >>> # TAP version 13 >>> # 1..0 # SKIP Transparent Hugepages not available >>> # [SKIP] >>> ok 6 split_huge_page_test /tmp/xfs_dir_YHPUPl # SKIP >>> >>> CC: Li Wang <[email protected]> >>> Signed-off-by: Chunyu Hu <[email protected]> >>> --- >>> tools/testing/selftests/mm/split_huge_page_test.c | 9 +++++++-- >>> 1 file changed, 7 insertions(+), 2 deletions(-) >>> >>> diff --git a/tools/testing/selftests/mm/split_huge_page_test.c >>> b/tools/testing/selftests/mm/split_huge_page_test.c >>> index e0167111bdd1..615b75ca62cc 100644 >>> --- a/tools/testing/selftests/mm/split_huge_page_test.c >>> +++ b/tools/testing/selftests/mm/split_huge_page_test.c >>> @@ -21,6 +21,7 @@ >>> #include <time.h> >>> #include "vm_util.h" >>> #include "kselftest.h" >>> +#include "thp_settings.h" >>> >>> uint64_t pagesize; >>> unsigned int pageshift; >>> @@ -255,7 +256,7 @@ static int check_after_split_folio_orders(char >>> *vaddr_start, size_t len, >>> return status; >>> } >>> >>> -static void write_file(const char *path, const char *buf, size_t buflen) >>> +static void safe_write_file(const char *path, const char *buf, size_t >>> buflen) >>> { >>> int fd; >>> ssize_t numwritten; >>> @@ -283,7 +284,7 @@ static void write_debugfs(const char *fmt, ...) >>> if (ret >= INPUT_MAX) >>> ksft_exit_fail_msg("%s: Debugfs input is too long\n", __func__); >>> >>> - write_file(SPLIT_DEBUGFS, input, ret + 1); >>> + safe_write_file(SPLIT_DEBUGFS, input, ret + 1); >>> } >>> >>> static char *allocate_zero_filled_hugepage(size_t len) >>> @@ -772,6 +773,10 @@ int main(int argc, char **argv) >>> ksft_finished(); >>> } >>> >>> + if (!thp_is_enabled()) { >>> + ksft_exit_skip("Transparent Hugepages not available\n"); >>> + } >>> + >>> if (argc > 1) >>> optional_xfs_path = argv[1]; >>> >>> -- >>> 2.53.0 >> >> >> Best Regards, >> Yan, Zi > > -- > Sincerely yours, > Mike. Best Regards, Yan, Zi
