Re: [PATCH v2 2/3] selftests/mm: add check_folio_orders() helper.

On 2025/8/9 03:01, Zi Yan wrote:

The helper gathers an folio order statistics of folios within a virtual address range and checks it against a given order list. It aims to provide a more precise folio order check instead of just checking the existence of PMD folios.

Signed-off-by: Zi Yan ziy@nvidia.com

.../selftests/mm/split_huge_page_test.c | 4 +- tools/testing/selftests/mm/vm_util.c | 133 ++++++++++++++++++ tools/testing/selftests/mm/vm_util.h | 7 + 3 files changed, 141 insertions(+), 3 deletions(-)

[snip]

+int check_folio_orders(char *vaddr_start, size_t len, int pagemap_file,

• 	int kpageflags_file, int orders[], int nr_orders)
  

+{

• int *vaddr_orders;
• int status;
• int i;
• vaddr_orders = (int *)malloc(sizeof(int) * nr_orders);
• if (!vaddr_orders)

• ksft_exit_fail_msg("Cannot allocate memory for vaddr_orders");
  

• memset(vaddr_orders, 0, sizeof(int) * nr_orders);
• status = gather_folio_orders(vaddr_start, len, pagemap_file,

• 		     kpageflags_file, vaddr_orders, nr_orders);
  

• if (status)

Missed calling free(vaddr_orders) before returning.

• return status;
  

• status = 0;
• for (i = 0; i < nr_orders; i++)

• if (vaddr_orders[i] != orders[i]) {
  

• 	ksft_print_msg("order %d: expected: %d got %d\n", i,
  

• 		       orders[i], vaddr_orders[i]);
  

• 	status = -1;
  

• }
  

Ditto.

• return status;

+}

• /* If `ioctls' non-NULL, the allowed ioctls will be returned into the var */ int uffd_register_with_ioctls(int uffd, void *addr, uint64_t len, bool miss, bool wp, bool minor, uint64_t *ioctls)

diff --git a/tools/testing/selftests/mm/vm_util.h b/tools/testing/selftests/mm/vm_util.h index 1843ad48d32b..02e3f1e7065b 100644 --- a/tools/testing/selftests/mm/vm_util.h +++ b/tools/testing/selftests/mm/vm_util.h @@ -18,6 +18,11 @@ #define PM_SWAP BIT_ULL(62) #define PM_PRESENT BIT_ULL(63) +#define KPF_COMPOUND_HEAD BIT_ULL(15) +#define KPF_COMPOUND_TAIL BIT_ULL(16) +#define KPF_THP BIT_ULL(22)

• /*
  • Ignore the checkpatch warning, we must read from x but don't want to do
  • anything with it in order to trigger a read page fault. We therefore must use

@@ -85,6 +90,8 @@ bool check_huge_shmem(void *addr, int nr_hpages, uint64_t hpage_size); int64_t allocate_transhuge(void *ptr, int pagemap_fd); unsigned long default_huge_page_size(void); int detect_hugetlb_page_sizes(size_t sizes[], int max); +int check_folio_orders(char *vaddr_start, size_t len, int pagemap_file,

• 	int kpageflags_file, int orders[], int nr_orders);
  

int uffd_register(int uffd, void *addr, uint64_t len, bool miss, bool wp, bool minor);