Re: [PATCH v3 5/5] selftests/resctrl: Fix resctrl_tests' return code to work with selftest framework

From: Shuah Khan
Date: Fri Feb 18 2022 - 15:39:39 EST


On 2/15/22 7:26 PM, Shaopeng Tan wrote:
In kselftest framework, if a sub test can not run by some reasons,
the test result should be marked as SKIP rather than FAIL.
Return KSFT_SKIP(4) instead of KSFT_FAIL(1) if resctrl_tests is not run
as root or it is run on a test environment which does not support resctrl.

- ksft_exit_fail_msg(): returns KSFT_FAIL(1)
- ksft_exit_skip(): returns KSFT_SKIP(4)


Thank for making this change to skip.

Signed-off-by: Shaopeng Tan <tan.shaopeng@xxxxxxxxxxxxxx>
---
Some important feedbacks from v1&v2 are addressed as follows:

- It is important to highlight that a skipped test is marked
as successful to not unnecessarily report a feature failure
when there actually is a failure in the test environment.
=> I highligted this content in changelog as follows.
"In kselftest framework, if a test is not run by some reason,
the test result is marked as SKIP rather than FAIL."

- The subject line can be made more succinct while the details are
moved to the commit message.
=> I made subject line succinct and moved the details to changelog.

- How changing ksft_exit_fail_msg() to ksft_exit_skip() accomplishes
the goal of unifying the return code.
=> In changelog, I explained why return code KSFT_SKIP(4) is needed
in kselftest framework and the return code of each function.

tools/testing/selftests/resctrl/resctrl_tests.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/resctrl/resctrl_tests.c b/tools/testing/selftests/resctrl/resctrl_tests.c
index 973f09a66e1e..3be0895c492b 100644
--- a/tools/testing/selftests/resctrl/resctrl_tests.c
+++ b/tools/testing/selftests/resctrl/resctrl_tests.c
@@ -205,7 +205,7 @@ int main(int argc, char **argv)
* 2. We execute perf commands
*/
if (geteuid() != 0)
- return ksft_exit_fail_msg("Not running as root, abort testing.\n");
+ return ksft_exit_skip("Not running as root, abort testing.\n");

Let's update the message to "This test must be run as root. Skipping..."
/* Detect AMD vendor */
detect_amd();
@@ -235,7 +235,7 @@ int main(int argc, char **argv)
sprintf(bm_type, "fill_buf");
if (!check_resctrlfs_support())
- return ksft_exit_fail_msg("resctrl FS does not exist\n");
+ return ksft_exit_skip("resctrl FS does not exist\n");

Update the message to read -

"resctrl FS doesn not exist. Enable X86_CPU_RESCTRL and PROC_CPU_RESCTRL config options"

filter_dmesg();


With these changes:

Reviewed-by: Shuah Khan <skhan@xxxxxxxxxxxxxxxxxxx>

thanks,
-- Shuah