Commit 735b3f7e authored by Ryan Roberts's avatar Ryan Roberts Committed by Andrew Morton
Browse files

selftests/mm: uffd-unit-tests support for hugepages > 2M 

uffd-unit-tests uses a memory area with a fixed 32M size.  Then it
calculates the number of pages by dividing by page_size, which itself is
either the base page size or the PMD huge page size depending on the test
config.  For the latter, we end up with nr_pages=1 for arm64 16K base
pages, and nr_pages=0 for 64K base pages.  This doesn't end well.

So let's make the 32M size a floor and also ensure that we have at least 2
pages given the PMD size.  With this change, the tests pass on arm64 64K
base page size configuration.

Link: https://lkml.kernel.org/r/20250318174343.243631-2-ryan.roberts@arm.com


Signed-off-by: default avatarRyan Roberts <ryan.roberts@arm.com>
Acked-by: default avatarPeter Xu <peterx@redhat.com>
Acked-by: default avatarRafael Aquini <raquini@redhat.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent af96c610

tools/testing/selftests/mm/uffd-unit-tests.c

+4 −1
Original line number Diff line number Diff line
@@ -26,6 +26,8 @@ 
#define ALIGN_UP(x, align_to) \

	((__typeof__(x))((((unsigned long)(x)) + ((align_to)-1)) & ~((align_to)-1)))



#define MAX(a, b) (((a) > (b)) ? (a) : (b))



struct mem_type {

	const char *name;

	unsigned int mem_flag;
@@ -196,7 +198,8 @@ uffd_setup_environment(uffd_test_args_t *args, uffd_test_case_t *test, 
	else

		page_size = psize();



	nr_pages = UFFD_TEST_MEM_SIZE / page_size;

	/* Ensure we have at least 2 pages */

	nr_pages = MAX(UFFD_TEST_MEM_SIZE, page_size * 2) / page_size;

	/* TODO: remove this global var.. it's so ugly */

	nr_parallel = 1;