> On 8/26/26 14:24, Yeoreum Yun wrote: > > There're some random failure for split_huge_page_test when khugepaged > > collapses pages into pmd again which had split by the test. > > > > Prevent the khugepaged's collapses for split page by setting the > > mapped pmd-huge-page with MADV_NOHUGEPAGE before split. > > > > Reported-by: Kevin Brodsky <[email protected]> > > Reviewed-by: Zi Yan <[email protected]> > > Signed-off-by: Yeoreum Yun <[email protected]> > > --- > > tools/testing/selftests/mm/split_huge_page_test.c | 15 +++++++++++++++ > > 1 file changed, 15 insertions(+) > > > > diff --git a/tools/testing/selftests/mm/split_huge_page_test.c > > b/tools/testing/selftests/mm/split_huge_page_test.c > > index 86a603692826..8f68bc94a5ca 100644 > > --- a/tools/testing/selftests/mm/split_huge_page_test.c > > +++ b/tools/testing/selftests/mm/split_huge_page_test.c > > @@ -180,6 +180,10 @@ static void > > verify_rss_anon_split_huge_page_all_zeroes(char *one_page, int nr_hp > > if (!rss_anon_before) > > ksft_exit_fail_msg("No RssAnon is allocated before split\n"); > > > > + /* Prevent khugepaged from collapsing the pages. */ > > + if (madvise(one_page, len, MADV_NOHUGEPAGE)) > > + ksft_print_msg("MADV_NOHUGEPAGE failed to prevent khugepaged > > from collapsing pages.\n"); > > + > > Ok, this is really only expected to fail on extremely old kernels or kernels > without CONFIG_TRANSPARENT_HUGEPAGE (where we should never get to that point > :) ). > > Can we just turn that into a > ksft_exit_fail_perror("madvise(MADV_NOHUGEPAGE)"); > > I'm okay with a ksft_print_msg() as well, but would shorten the message quite > a > lot ("MADV_NOHUGEPAGE failed" or sth).
Thanks. I'll change the message only then. -- Sincerely, Yeoreum Yun
