Re: [PATCH] selftest: hugetlb_dio: Fix test naming

[Donet Tom <donettom@linux.ibm.com>]

On 11/27/24 21:44, Mark Brown wrote:
> The string logged when a test passes or fails is used by the selftest
> framework to identify which test is being reported. The hugetlb_dio test
> not only uses the same strings for every test that is run but it also uses
> different strings for test passes and failures which means that test
> automation is unable to follow what the test is doing at all.
>
> Pull the existing duplicated logging of the number of free huge pages
> before and after the test out of the conditional and replace that and the
> logging of the result with a single ksft_print_result() which incorporates
> the parameters passed into the test into the output.
>
> Fixes: fae1980347bf ("selftests: hugetlb_dio: fixup check for initial conditions to skip in the start")
> Signed-off-by: Mark Brown <broonie@kernel.org>
> ---
>   tools/testing/selftests/mm/hugetlb_dio.c | 14 +++++---------
>   1 file changed, 5 insertions(+), 9 deletions(-)
>
> diff --git a/tools/testing/selftests/mm/hugetlb_dio.c b/tools/testing/selftests/mm/hugetlb_dio.c
> index 432d5af15e66b7d6cac0273fb244d6696d7c9ddc..db63abe5ee5e85ff7795d3ea176c3ac47184bf4f 100644
> --- a/tools/testing/selftests/mm/hugetlb_dio.c
> +++ b/tools/testing/selftests/mm/hugetlb_dio.c
> @@ -76,19 +76,15 @@ void run_dio_using_hugetlb(unsigned int start_off, unsigned int end_off)
>   	/* Get the free huge pages after unmap*/
>   	free_hpage_a = get_free_hugepages();
>   
> +	ksft_print_msg("No. Free pages before allocation : %d\n", free_hpage_b);
> +	ksft_print_msg("No. Free pages after munmap : %d\n", free_hpage_a);
> +
>   	/*
>   	 * If the no. of free hugepages before allocation and after unmap does
>   	 * not match - that means there could still be a page which is pinned.
>   	 */
> -	if (free_hpage_a != free_hpage_b) {
> -		ksft_print_msg("No. Free pages before allocation : %d\n", free_hpage_b);
> -		ksft_print_msg("No. Free pages after munmap : %d\n", free_hpage_a);
> -		ksft_test_result_fail(": Huge pages not freed!\n");
> -	} else {
> -		ksft_print_msg("No. Free pages before allocation : %d\n", free_hpage_b);
> -		ksft_print_msg("No. Free pages after munmap : %d\n", free_hpage_a);
> -		ksft_test_result_pass(": Huge pages freed successfully !\n");
> -	}
> +	ksft_test_result(free_hpage_a == free_hpage_b,
> +			 "free huge pages from %u-%u\n", start_off, end_off);

Hi Mark

This test allocates a hugetlb buffer and adjusts the start and end offsets of the buffer based
on|start_off|  and|end_off|. The adjusted buffer is then used for Direct I/O (DIO). If I understand
correctly,|start_off|  and|end_off|  are not free huge pages but rather DIO buffer offsets. Should we
change this message to "Hugetlb DIO buffer offset"?

Thanks
Donet

>   }
>   
>   int main(void)
>
> ---
> base-commit: 6f3d2b5299b0a8bcb8a9405a8d3fceb24f79c4f0
> change-id: 20241127-kselftest-mm-hugetlb-dio-names-1ebccbe8183d
>
> Best regards,