[PATCH bpf v1 2/3] selftests/bpf: Print a message when tester could not run a program

[Krzesimir Nowak <krzesimir@kinvolk.io>]

This prints a message when the error is about program type being not
supported by the test runner or because of permissions problem. This
is to see if the program we expected to run was actually executed.

The messages are open-coded because strerror(ENOTSUPP) returns
"Unknown error 524".

Signed-off-by: Krzesimir Nowak <krzesimir@kinvolk.io>
---
 tools/testing/selftests/bpf/test_verifier.c | 17 +++++++++++++----
 1 file changed, 13 insertions(+), 4 deletions(-)

diff --git a/tools/testing/selftests/bpf/test_verifier.c b/tools/testing/selftests/bpf/test_verifier.c
index ccd896b98cac..bf0da03f593b 100644
--- a/tools/testing/selftests/bpf/test_verifier.c
+++ b/tools/testing/selftests/bpf/test_verifier.c
@@ -825,11 +825,20 @@ static int do_prog_test_run(int fd_prog, bool unpriv, uint32_t expected_val,
 				tmp, &size_tmp, &retval, NULL);
 	if (unpriv)
 		set_admin(false);
-	if (err && errno != 524/*ENOTSUPP*/ && errno != EPERM) {
-		printf("Unexpected bpf_prog_test_run error ");
-		return err;
+	if (err) {
+		switch (errno) {
+		case 524/*ENOTSUPP*/:
+			printf("Did not run the program (not supported) ");
+			return 0;
+		case EPERM:
+			printf("Did not run the program (no permission) ");
+			return 0;
+		default:
+			printf("Unexpected bpf_prog_test_run error ");
+			return err;
+		}
 	}
-	if (!err && retval != expected_val &&
+	if (retval != expected_val &&
 	    expected_val != POINTER_VALUE) {
 		printf("FAIL retval %d != %d ", retval, expected_val);
 		return 1;
-- 
2.20.1