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Howlett" , Nico Pache , Ryan Roberts , Dev Jain , Barry Song , Lance Yang , Usama Arif , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Shuah Khan , Kevin Brodsky Cc: linux-mm@kvack.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org, Yeoreum Yun X-Mailer: b4 0.13.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=2698; i=yeoreum.yun@arm.com; h=from:subject:message-id; bh=GvQPZ0sVbuduLvQoOF9zM5jXfFX1CSDKvuBA3qmf1I8=; b=owEB7QES/pANAwAKAW3Vw9FaxTEzAcsmYgBqjtsbim5lcCrKm1NTonGxRpo+/uWXYt6fnVqSW 2zH3AZ2+mCJAbMEAAEKAB0WIQQtg+CS3QUzuFh1pJ1t1cPRWsUxMwUCao7bGwAKCRBt1cPRWsUx Mwl1C/9wWoLo2TBd76OtUebEOO9bmK1IDPaAImCIYUhdFcULi+QtYiaD5Dv95d2w/ur8IbUve0/ H1XJHff2OIt+Cggqmtqw128mL2F0wo+Ak2JZVW1KB0oc8lsbyMHXDswwrZb0lkBh+0IiT5Ne7YT XyWGemLyMoggKrStCYhAzx8H4sr4VrxcNAccO8j6O0VFuSW3sgpMTBNRUhhfMUQYkmwiZPMdXO8 T5/MIBY4rMwZNSg6ouXnHnjQG3F6eFj70MDP7EWR3OijfONE9hx4JIcOGtxEka+E9mizpeb26JB ehhQPMO0HbnfXVEWvsaRprxpwpckBw4s5L0mqQAqmNgcJLUIUsMEtBwToVd8lDBxN3szlymtN54 FKJ3ajlgig/fmTN3Mu/I0vBW8wfk37ly69RS90mhuL5kysqhLDErYPnXRWKTBuLBn0AGEIG0AhK /S6GF2qbFCM5LXkiORwjKDIqJLKgTnL8xI4evcfrQX8SFj+13hXf6XWXjbOXX0qRKgRc8= X-Developer-Key: i=yeoreum.yun@arm.com; a=openpgp; fpr=2D83E092DD0533B85875A49D6DD5C3D15AC53133 X-Stat-Signature: jmadw1naw8pmeygqgj3anidab933wkuh X-Rspamd-Server: rspam12 X-Rspamd-Queue-Id: 0C902A000C X-Rspam-User: X-HE-Tag: 1787747107-768003 X-HE-Meta: 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 tvxT+133 ASoOxBe0CQl8zcdyMIP/6F5Zqn7PuuoMv0lCWdBbInGl5CV8FUoKJj0hprYbiy7waVnKcoh1lLprqw02MLrc9xv+oUjYLS3OLRCp8LY59exfPoSnSEpkoFTuguOWqM/WaLRMLXisDMdk347XXxA4skIwY9w4/dGXE+eGM8wjOe36uGMO4SuUOghBOB+JiWTvzwZW6Be5eH8YzQ2y9wUJZmJ99cS+gNBzo4WLAEZrixaIXs5R7Ea6MAzFHMKWO3Yn5cHjhsyZySoicAJYUTiqGcGGBNA== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: 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 Reviewed-by: Zi Yan Signed-off-by: Yeoreum Yun --- 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"); + /* split all THPs */ write_debugfs(PID_FMT, getpid(), (uint64_t)one_page, (uint64_t)one_page + len, 0); @@ -227,6 +231,10 @@ static void split_pmd_thp_to_order(int order) if (!check_huge_anon(one_page, 4 * pmd_pagesize, 4, pmd_pagesize)) ksft_exit_fail_msg("No THP is allocated\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"); + /* split all THPs */ write_debugfs(PID_FMT, getpid(), (uint64_t)one_page, (uint64_t)one_page + len, order); @@ -313,6 +321,10 @@ static void split_pte_mapped_thp(void) goto out; } + /* Prevent khugepaged from collapsing the pages. */ + if (madvise(thp_area, thp_area_size, MADV_NOHUGEPAGE)) + ksft_print_msg("MADV_NOHUGEPAGE failed to prevent khugepaged from collapsing pages.\n"); + /* Split all THPs through the remapped pages. */ write_debugfs(PID_FMT, getpid(), (uint64_t)page_area, (uint64_t)page_area + page_area_size, 0); @@ -542,6 +554,9 @@ static int create_pagecache_thp_and_fd(const char *testfile, size_t fd_size, ksft_test_result_skip("Pagecache folio split skipped\n"); return -2; } + /* Prevent khugepaged from collapsing the pages. */ + if (madvise(*addr, fd_size, MADV_NOHUGEPAGE)) + ksft_print_msg("MADV_NOHUGEPAGE failed to prevent khugepaged from collapsing pages.\n"); return 0; err_out_close: close(*fd); -- 2.43.0