Re: [PATCH v3 18/54] selftests/mm: uffd-stress: use kselftest framework

[Sarthak Sharma <sarthak.sharma@arm.com>]

On 4/29/26 2:12 AM, Mike Rapoport wrote:
> From: "Mike Rapoport (Microsoft)" <rppt@kernel.org>
> 
> Convert uffd-stress test to use kselftest framework for reporting and
> tracking successful and failing runs.
> 
> Reviewed-by: Mark Brown <broonie@kernel.org>
> Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org>

I've run the test before and after applying the patch. The patch
correctly formats the output according to KTAP format with no change in
results.

Tested-by: Sarthak Sharma <sarthak.sharma@arm.com>

> ---
>  tools/testing/selftests/mm/uffd-stress.c | 41 +++++++++++-------------
>  1 file changed, 19 insertions(+), 22 deletions(-)
> 
> diff --git a/tools/testing/selftests/mm/uffd-stress.c b/tools/testing/selftests/mm/uffd-stress.c
> index 700fbaa18d44..e92a85463eb1 100644
> --- a/tools/testing/selftests/mm/uffd-stress.c
> +++ b/tools/testing/selftests/mm/uffd-stress.c
> @@ -286,19 +286,12 @@ static int userfaultfd_stress(uffd_global_test_opts_t *gopts)
>  	pthread_attr_setstacksize(&attr, 16*1024*1024);
>  
>  	while (bounces--) {
> -		printf("bounces: %d, mode:", bounces);
> -		if (bounces & BOUNCE_RANDOM)
> -			printf(" rnd");
> -		if (bounces & BOUNCE_RACINGFAULTS)
> -			printf(" racing");
> -		if (bounces & BOUNCE_VERIFY)
> -			printf(" ver");
> -		if (bounces & BOUNCE_POLL)
> -			printf(" poll");
> -		else
> -			printf(" read");
> -		printf(", ");
> -		fflush(stdout);
> +		ksft_print_msg("bounces: %d, mode:%s%s%s%s, ",
> +			       bounces,
> +			       bounces & BOUNCE_RANDOM ? " rnd" : "",
> +			       bounces & BOUNCE_RACINGFAULTS ? " racing" : "",
> +			       bounces & BOUNCE_VERIFY ? " ver" : "",
> +			       bounces & BOUNCE_POLL ? " poll" : " read");
>  
>  		if (bounces & BOUNCE_POLL)
>  			fcntl(gopts->uffd, F_SETFL, gopts->uffd_flags | O_NONBLOCK);
> @@ -456,6 +449,9 @@ int main(int argc, char **argv)
>  	unsigned long nr_cpus;
>  	size_t bytes;
>  
> +	ksft_print_header();
> +	ksft_set_plan(1);
> +
>  	gopts = (uffd_global_test_opts_t *) malloc(sizeof(uffd_global_test_opts_t));
>  
>  	if (argc < 4)
> @@ -484,10 +480,8 @@ int main(int argc, char **argv)
>  	 * for racy extra reservation of hugepages.
>  	 */
>  	if (gopts->test_type == TEST_HUGETLB &&
> -	   get_free_hugepages() < 2 * (bytes / gopts->page_size) + gopts->nr_parallel - 1) {
> -		printf("skip: Skipping userfaultfd... not enough hugepages\n");
> -		return KSFT_SKIP;
> -	}
> +	   get_free_hugepages() < 2 * (bytes / gopts->page_size) + gopts->nr_parallel - 1)
> +		ksft_exit_skip("Skipping userfaultfd... not enough hugepages\n");
>  
>  	gopts->nr_pages_per_cpu = bytes / gopts->page_size / gopts->nr_parallel;
>  	if (!gopts->nr_pages_per_cpu) {
> @@ -503,9 +497,12 @@ int main(int argc, char **argv)
>  	}
>  	gopts->nr_pages = gopts->nr_pages_per_cpu * gopts->nr_parallel;
>  
> -	printf("nr_pages: %lu, nr_pages_per_cpu: %lu\n",
> -	       gopts->nr_pages, gopts->nr_pages_per_cpu);
> -	return userfaultfd_stress(gopts);
> +	ksft_print_msg("nr_pages: %lu, nr_pages_per_cpu: %lu\n",
> +		       gopts->nr_pages, gopts->nr_pages_per_cpu);
> +
> +	ksft_test_result(!userfaultfd_stress(gopts),
> +			 "uffd-stress %s\n", argv[1]);
> +	ksft_finished();
>  }
>  
>  #else /* __NR_userfaultfd */
> @@ -514,8 +511,8 @@ int main(int argc, char **argv)
>  
>  int main(void)
>  {
> -	printf("skip: Skipping userfaultfd test (missing __NR_userfaultfd)\n");
> -	return KSFT_SKIP;
> +	ksft_print_header();
> +	ksft_exit_skip("missing __NR_userfaultfd definition\n");
>  }
>  
>  #endif /* __NR_userfaultfd */