On Fri, Aug 03, 2018 at 07:00:44PM -0300, Thiago Jung Bauermann wrote:
> Since there's no point in doing anything in this case, immediately exit the
> process.
>
> And take the opportunity to improve the error message.
>
> Before:
>
> # ./userfaultfd shmem 10 10
> nr_pages: 160, nr_pages_per_cpu: 40
> userfaultfd syscall not available in this kernel
> # echo $?
> 1
>
> After:
>
> # ./userfaultfd shmem 10 10
> nr_pages: 160, nr_pages_per_cpu: 40
> userfaultfd syscall not available in this kernel: Function not implemented
> # echo $?
> 4
>
> Suggested-by: Mike Rapoport <r...@linux.vnet.ibm.com>
> Signed-off-by: Thiago Jung Bauermann <bauer...@linux.ibm.com>
Acked-by: Mike Rapoport <r...@linux.vnet.ibm.com>
> ---
> tools/testing/selftests/vm/userfaultfd.c | 8 +++++---
> 1 file changed, 5 insertions(+), 3 deletions(-)
>
> diff --git a/tools/testing/selftests/vm/userfaultfd.c
> b/tools/testing/selftests/vm/userfaultfd.c
> index e4099afe7557..d728bd1cb33c 100644
> --- a/tools/testing/selftests/vm/userfaultfd.c
> +++ b/tools/testing/selftests/vm/userfaultfd.c
> @@ -636,9 +636,11 @@ static int userfaultfd_open(int features)
>
> uffd = syscall(__NR_userfaultfd, O_CLOEXEC | O_NONBLOCK);
> if (uffd < 0) {
> - fprintf(stderr,
> - "userfaultfd syscall not available in this kernel\n");
> - return 1;
> + int errnum = errno;
> +
> + perror("userfaultfd syscall not available in this kernel");
> +
> + exit(errnum == ENOSYS ? KSFT_SKIP : 1);
> }
> uffd_flags = fcntl(uffd, F_GETFD, NULL);
>
--
Sincerely yours,
Mike.
