RE: [PATCH 2/3] selftests/resctrl: Return KSFT_SKIP(4) if resctrl filessystem is not supported or resctrl is not run as root

[tan.shaopeng@xxxxxxxxxxx]

Hi Reinette
 
> (subject line and commit message: filessystem -> file system)
Thanks.
 
> On 11/10/2021 1:33 AM, Shaopeng Tan wrote:
> > From: "Tan, Shaopeng" <tan.shaopeng@xxxxxxxxxxxxxx>
> >
> > To unify the return code of resctrl_tests with the return code of
> > selftest set, return KSFT_SKIP (4) if resctrl filessystem is not
> > supported or resctrl is not run as root.
> 
> Could you please elaborate how changing ksft_exit_fail_msg() to
> ksft_exit_skip() accomplishes the goal of unifying the return code?
> What is wrong with using ksft_exit_fail_msg()?

In selftest framwork, 
if a test need root privileges, but it is run as user privileges,
the test result will counted as a SKIP item, instead of a FAIL item.

For example, 
(1)tools/testing/selftests/mqueue/mq_open_tests.c
267         if (getuid() != 0) 
268                 ksft_exit_skip("Not running as root, but almost all tests "
269                         "require root in order to modify\nsystem settings.  "
270                         "Exiting.\n"); 

(2)tools/testing/selftests/bpf/test_kmod.sh
  5 ksft_skip=4
  6 
  7 msg="skip all tests:"
  8 if [ "$(id -u)" != "0" ]; then
  9         echo $msg please run this as root >&2
 10         exit $ksft_skip
 11 fi

Regards, 
Shaopeng Tan