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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=8322; i=yeoreum.yun@arm.com; h=from:subject:message-id; bh=SjfNrQGkpA3X9nEyXuOHe2XZDuXDkedMucJlksznh2E=; b=owEB7QES/pANAwAKAW3Vw9FaxTEzAcsmYgBqmBIGChN4Z/69/a8p/NDwEvJkPUxXNn52hUppN 56OwlIXil2JAbMEAAEKAB0WIQQtg+CS3QUzuFh1pJ1t1cPRWsUxMwUCapgSBgAKCRBt1cPRWsUx MwckDACsk24Kt5Y9WNpyRadANFyOgMdwdOg1bJ2L7UYNeHQBnB98PQvTfy6CyJi2Vfbt5/ekH6U rxHRkn1wWDRj7MVRHYY8nIuDbJXtDw4rFRaeRlsx4YB6NnrQ6ldbLtD8/Zp3ryBAATb8S3t8t3O DBOKxQZfyVhjFNC9Dvulm38uonad/iNkoj9exikuxDbTYj3aMwA02oyxntPBsR4pfcM8f2Yl/sY arTg5AeamU2PgV4ZwBKny79p0Cx4w8EXKrrgUmn9DeVI2v+H0xrQ8s2i3kOvrpXM9E/oGZZiBSV pDC2QtuVUPgwIeH4A1eia+kH56Cvj3f6he2wwfgvk0v44SS23uVvS0dzL7r3YmRzHLa3Z1NwmkZ UHo1z/VSKAhv4iYVmxpigtH/gFcqw6cJ9NbGuh9AGLkW35ryQ74AeBz/d0veKddFM+bW9zwwRBH kyYBqLyghJG6+jiPf9wCTyA2P+Rr2ShrqqZbmMkJWAmdp4/Z6Zew3R+MnJFR/gn1jaIF0= X-Developer-Key: i=yeoreum.yun@arm.com; a=openpgp; fpr=2D83E092DD0533B85875A49D6DD5C3D15AC53133 X-Rspamd-Server: rspam11 X-Rspam-User: X-Stat-Signature: ug7eunrqejihacyp3cc3kh4kp9fiycaq X-Rspamd-Queue-Id: 3CF82140011 X-HE-Tag: 1788350994-124951 X-HE-Meta: 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 UAIwHA8E heFq6fXJChG4LdRECccHQE5bZvFBppNTexkB7nPg5nRxCAM0eURXXKAEkQnx06iB+aq/zzhnuxCde9S7q0oxuzZF1W/FnBC3rJjM2O6GnjyeH5tr3F8gYq4R1LRoRijz/6zIuuZXTwYkrUKadZXnvMfJpDC0tlxBPMufCLTcW4vsJ+8dmQDdZrMGfEWhrpkQIqzZvpW6K9Dei/svtRfY7iHfixJMZFTPLS2EO17ikbbVP8CRz5ThD/xacEaQFVivlvObFJX0fnrerXaS4op4X5olydXRn/zlPKdJlOi/aosd2CiGPwUKlub1weqcll9lf99aQBTCnAM69USGwVp/+Vu8UVlYBS3yjVoQSv4MM2arK7/LfTeyEwsbeFsG3lwqPzVgzU0mbNHllVTY= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: Since glibc commit 321e1fc73f (“malloc: Enable 2MB THP by default on AArch64”), glibc may call madvise(MADV_HUGEPAGE) for sufficiently large allocations made by memalign(). The underlying VMA may start at a different address from the aligned address returned by memalign(). Furthermore, a subsequent madvise(MADV_HUGEPAGE) call does not split the VMA because the flag is already set. This causes split_huge_page_test to fail because the check_huge_xxx() helpers incorrectly require the address returned by memalign() to match the VMA start address reported in /proc/self/smaps. Instead of relying on /proc/self/smaps, use /proc/self/pagemap and /proc/kpageflags to detect huge-page mappings and large folios: 1. If hpage_size == pmd_pagesize, check PAGE_IS_HUGE instead of using check_large_folios(), since only the mapping type matters. This identifies PMD-mapped huge pages. 2. Otherwise, use check_large_folios() to detect large folios. This covers mTHP cases. 3. Check the folio flags according to the type of huge page. Suggested-by: David Hildenbrand (Arm) Suggested-by: Zi Yan Reviewed-by: Zi Yan Reviewed-by: Baolin Wang Tested-by: Baolin Wang Acked-by: Lorenzo Stoakes (ARM) Signed-off-by: Yeoreum Yun --- tools/testing/selftests/mm/vm_util.c | 145 ++++++++++++++++++++++------------- tools/testing/selftests/mm/vm_util.h | 1 + 2 files changed, 92 insertions(+), 54 deletions(-) diff --git a/tools/testing/selftests/mm/vm_util.c b/tools/testing/selftests/mm/vm_util.c index 4821a3563036..dc62ce84e143 100644 --- a/tools/testing/selftests/mm/vm_util.c +++ b/tools/testing/selftests/mm/vm_util.c @@ -351,31 +351,13 @@ char *__get_smap_entry(void *addr, const char *pattern, char *buf, size_t len) return entry; } -static bool __check_pmd_huge(void *addr, char *pattern, int nr_hpages, - uint64_t hpage_size) -{ - char buffer[MAX_LINE_LENGTH]; - uint64_t thp = -1; - char *entry; - - entry = __get_smap_entry(addr, pattern, buffer, sizeof(buffer)); - if (!entry) - goto err_out; - - if (sscanf(entry, "%9" SCNu64 " kB", &thp) != 1) - ksft_exit_fail_msg("Reading smap error\n"); - -err_out: - return thp == (nr_hpages * (hpage_size >> 10)); -} - -static bool check_large_folios(void *addr, size_t len, int nr_hpages, - uint64_t hpage_size) +static bool check_large_folios(int pagemap_fd, int kpageflags_fd, + void *addr, size_t len, int nr_hpages, + uint64_t hpage_size) { int order = 0, pagesize = getpagesize(); unsigned int nr_pages = hpage_size / pagesize; int orders[MAX_NR_ORDERS], status; - int pagemap_fd, kpageflags_fd; bool ret = false; if (!nr_pages) @@ -386,15 +368,6 @@ static bool check_large_folios(void *addr, size_t len, int nr_hpages, ksft_exit_fail_msg("invalid order\n"); memset(orders, 0, sizeof(int) * MAX_NR_ORDERS); - pagemap_fd = open(PAGEMAP_PATH, O_RDONLY); - if (pagemap_fd == -1) - ksft_exit_fail_msg("read pagemap fail\n"); - - kpageflags_fd = open(KPAGEFLAGS_PATH, O_RDONLY); - if (kpageflags_fd == -1) { - close(pagemap_fd); - ksft_exit_fail_msg("read kpageflags fail\n"); - } status = gather_folio_orders(addr, len, pagemap_fd, kpageflags_fd, orders, MAX_NR_ORDERS); @@ -405,48 +378,112 @@ static bool check_large_folios(void *addr, size_t len, int nr_hpages, ret = true; out: - close(pagemap_fd); - close(kpageflags_fd); return ret; } -bool check_huge_anon(void *addr, size_t len, int nr_hpages, uint64_t hpage_size) -{ - uint64_t pmd_pagesize = read_pmd_pagesize(); - - if (!pmd_pagesize) - ksft_exit_fail_msg("reading PMD pagesize failed\n"); +enum check_huge_type { + CHECK_HUGE_ANON, + CHECK_HUGE_FILE, + CHECK_HUGE_SHMEM, +}; - if (hpage_size == pmd_pagesize) - return __check_pmd_huge(addr, "AnonHugePages: ", nr_hpages, hpage_size); +static bool check_huge_type(uint64_t categories, uint64_t kpageflags, + enum check_huge_type type) +{ + const bool file = categories & PAGE_IS_FILE; + const bool swapbacked = kpageflags & KPF_SWAPBACKED; + + switch (type) { + case CHECK_HUGE_ANON: + return !file; + case CHECK_HUGE_FILE: + return file && !swapbacked; + case CHECK_HUGE_SHMEM: + return file & swapbacked; + } - return check_large_folios(addr, len, nr_hpages, hpage_size); + return false; } -bool check_huge_file(void *addr, size_t len, int nr_hpages, uint64_t hpage_size) +static bool __check_huge(void *addr, size_t len, int nr_hpages, + uint64_t hpage_size, enum check_huge_type type) { - uint64_t pmd_pagesize = read_pmd_pagesize(); + bool ret = false; + int pagemap_fd, kpageflags_fd; + int nr_pmd_mappings = 0; + uint64_t pmd_pagesize, scan_mapping_size; + uint64_t categories, kpf; + unsigned long pfn; + bool check_pmd_mapping, allow_nonpresent; + char *start = addr; + char *end = start + len; + pmd_pagesize = read_pmd_pagesize(); if (!pmd_pagesize) ksft_exit_fail_msg("reading PMD pagesize failed\n"); - if (hpage_size == pmd_pagesize) - return __check_pmd_huge(addr, "FilePmdMapped:", nr_hpages, hpage_size); + check_pmd_mapping = (hpage_size == pmd_pagesize); + scan_mapping_size = (nr_hpages > 0) ? hpage_size : psize(); + /* Some mTHP tests check a partially populated PMD-sized range. */ + allow_nonpresent = (uint64_t)nr_hpages * hpage_size < len; - return check_large_folios(addr, len, nr_hpages, hpage_size); + pagemap_fd = open(PAGEMAP_PATH, O_RDONLY); + if (pagemap_fd < 0) + ksft_exit_fail_msg("open pagemap fail\n"); + + kpageflags_fd = open(KPAGEFLAGS_PATH, O_RDONLY); + if (kpageflags_fd < 0) { + close(pagemap_fd); + ksft_exit_fail_msg("open kpageflags fail\n"); + } + + if (!check_pmd_mapping && + !check_large_folios(pagemap_fd, kpageflags_fd, + addr, len, nr_hpages, hpage_size)) + goto out; + + for (; start < end; start += scan_mapping_size) { + categories = pagemap_scan_get_categories(pagemap_fd, start); + pfn = pagemap_get_pfn(pagemap_fd, start); + if (pfn == -1UL) { + if (!allow_nonpresent) + goto out; + else + continue; + } + if (pageflags_get(pfn, kpageflags_fd, &kpf)) + ksft_exit_fail_msg("read kpageflags: %s\n", strerror(errno)); + if (check_pmd_mapping && (categories & PAGE_IS_HUGE)) + nr_pmd_mappings++; + if (kpf & KPF_COMPOUND_TAIL) + continue; + if (!check_huge_type(categories, kpf, type)) + goto out; + } + + if (check_pmd_mapping && (nr_pmd_mappings != nr_hpages)) + goto out; + ret = true; + +out: + close(pagemap_fd); + close(kpageflags_fd); + return ret; } -bool check_huge_shmem(void *addr, size_t len, int nr_hpages, uint64_t hpage_size) +bool check_huge_anon(void *addr, size_t len, int nr_hpages, uint64_t hpage_size) { - uint64_t pmd_pagesize = read_pmd_pagesize(); - - if (!pmd_pagesize) - ksft_exit_fail_msg("reading PMD pagesize failed\n"); + return __check_huge(addr, len, nr_hpages, hpage_size, CHECK_HUGE_ANON); +} - if (hpage_size == pmd_pagesize) - return __check_pmd_huge(addr, "ShmemPmdMapped:", nr_hpages, hpage_size); +bool check_huge_file(void *addr, size_t len, int nr_hpages, uint64_t hpage_size) +{ + return __check_huge(addr, len, nr_hpages, hpage_size, CHECK_HUGE_FILE); +} - return check_large_folios(addr, len, nr_hpages, hpage_size); +bool check_huge_shmem(void *addr, size_t len, int nr_hpages, uint64_t hpage_size) +{ + return __check_huge(addr, len, nr_hpages, hpage_size, CHECK_HUGE_SHMEM); } int64_t allocate_transhuge(void *ptr, int pagemap_fd) diff --git a/tools/testing/selftests/mm/vm_util.h b/tools/testing/selftests/mm/vm_util.h index 9a49af88702e..f19bd17817e5 100644 --- a/tools/testing/selftests/mm/vm_util.h +++ b/tools/testing/selftests/mm/vm_util.h @@ -18,6 +18,7 @@ #define PM_SWAP BIT_ULL(62) #define PM_PRESENT BIT_ULL(63) +#define KPF_SWAPBACKED BIT_ULL(14) #define KPF_COMPOUND_HEAD BIT_ULL(15) #define KPF_COMPOUND_TAIL BIT_ULL(16) #define KPF_HWPOISON BIT_ULL(19) -- 2.43.0