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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=7740; i=yeoreum.yun@arm.com; h=from:subject:message-id; bh=SSZ/dke2eJqfQi3JNnjQcCUtyxBe9Q8ye26urwOBivc=; b=owEB7QES/pANAwAKAW3Vw9FaxTEzAcsmYgBqkUK8H67Y8gy30FCcQx8m4fmdEselt1VQNJGTO oZ2eswZCdCJAbMEAAEKAB0WIQQtg+CS3QUzuFh1pJ1t1cPRWsUxMwUCapFCvAAKCRBt1cPRWsUx Mz2zDACjGmQpaW0+V1pmvHkE8DRj8W2cZg83EQgDjxm+EJXc+uB0as+VUb2fzEOpNYWVUymB787 jgOkNW72mFoEBfc670zw/yXmdpXZ9HHnQyrcUyKNPqA04jYiFeBk5yBUzVTRzfAwcxhhQfsq1dK Gy0WLQ2RRR5S/xHBjGAwg2tnA/D3k41ZWXntMxUdOybOFC4ytG9HmZyzI+CxhZXbkP+QHmI/P6l AF2ef7WUuLGtNSY9dVjR4I6te/pHue0++BPWlyG8vf1tR/cEsTUS26ZP3isl2nM8yHROzWMVREk zPH2RzxL+O0x8N1miL9R5LehjLvWBRHqV3Fd7LpT+CDH8iuOzR7YEqkKCop+3ZP0CfTyEwvj/I4 R1P0g6yPXUrRvJX3G9mWzdhn9PQEfLpkqyPSewBk0Li+W/mcpEhhs/GvzrM6qaD7dCYQGJcrOg7 f6cZZmcDZTHi+dRODhfBPgpxverQQ8BOP3AIcw5CYX34NQvXUbRoC5/6ZQIdRXGg/adRk= X-Developer-Key: i=yeoreum.yun@arm.com; a=openpgp; fpr=2D83E092DD0533B85875A49D6DD5C3D15AC53133 X-Stat-Signature: 3gh6ctorrgbo7ch776ajyx88gbowff7t X-Rspamd-Server: rspam09 X-Rspamd-Queue-Id: 93A3980003 X-Rspam-User: X-HE-Tag: 1787904709-658813 X-HE-Meta: U2FsdGVkX18Wd2jy1VkpBCUl/s3s4JWOi1/EI27L9hp8KXtK/UC0rmtf1JNsFqOtwpZbuc9TZ1rIddAuLp+yt6GrGryZ7Fdz+GejXsfNMQE5ISVVLXZfGa4WwxSfH5RuOTN5V7Hc/FaWToHpMCnFEhcBDdPUaTT69bkToSwUct2FdytMIK6vtg/uxhDiULc5YGd47+I9vZObBVqnqysQMJSHRoGIlXzotaVwbN5hjE1F6umJrDEbsmicHWiubjdGNbD2zyUSTjQJRguFZqE85qJMdJOdVVvoYccW+cjxews1CwSxsggGuPkkI1luhLKMIoVx7YJpaFOz/S5DevUdyf3X9NEUH1ZYKHMEwmz5v7ROm+3ywbzOTdlz/LSEKteCq7LQbQ4zGqnf2V+cE7XAuwuLzoLi3leUSef1Jm7m1IhPoDAGeG+DW5HLW4BiJXetdPKYS+RnuL85CYiXPByX1uCn7ACbW6nQFgbvdMV6RALwqR2aY+/kjnEoHb1Fe/jwjKvDTvhtymn8mX3HLwf5tTYkhcBVIYWLvP4zu2tzH6Jme7in69RDWZ0M41yZ0piSmfNVHTJYnGzfvXFnoOD/nLjZJXtw/LwD8xG6HIEBAqwRCwObYrltR3HegO3Kyx0eEgFCi9f735wsABpdPbjH1VT+yL3Qj0aZ6qrMWkQNMR1dQtU7PQCRI/qfgz+3rGpo8U03A5eJv8+9HTROoPdrnAvqN4cQrcEnr9eHsNxEyxpGr4O0qanIPP6FrMXbPgC3quvUd+W+2rQAgFfAROAV6GMLPH0BaKpoymF1IQtrX6Zx3fcb/+by6Iwgd4YNFsZQhir9+O+WeoODphRtGiyexnmu7DHG2S+ujvkM2KSkbKI/mzTcvwT6NECz4uX5UkuR7T2Vv5pheJ+MVS+O4F9PdQrX3rbHP6tuVSZ5O6B4w+bIi6GoAC5rDhmXTQKoF/MmechUaTlpXs2bLQmMEna LR36oUTG 5ZJg+/3kQ7q9B0qEY+UGRdcfmVqgnDfOqxN4LterghU8UA1chVw6UbG0ZWboQ9wu0NCsk4Gpl+p5kS4LhoHlRyXoYlZNbrGPf+QJeF6lhgTv5appYiwUPTqArDgAgoU0g0ELI1bgIuTzeVv8P6cS6gQC/oNcf/Xlyc7HP3hq78mQWn5zYhG6pbkXwoh4hook6fM3h+YfyX2wBxwqULSqP8VqRu2dKmmuxWvBn9cQtjnWXILimYjrPefZ8yKs7HYHhF7Usd+2czcuW61/ZDMX2cnXqaT+LzUVxsGZi0heUiLTP9Gu2xxSztkeYcbavgE1ePySMJUupPX9tLsenJcMQJ+54sMrxXMvTGSCgBOeTRd2KF/97Fl8fZH/Wxw== 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. Fix this by using /proc/self/pagemap and /proc/kpageflags instead of /proc/self/smaps to detect huge pages. Reported-by: David Hildenbrand (Arm) Suggested-by: Zi Yan 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..083b72d92b14 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) +{ + bool file = categories & PAGE_IS_FILE; + 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