selftest: timers: Tweak raw_skew to SKIP when ADJ_OFFSET/other clock adjustments...

[ Upstream commit 1416270f4a1ae83ea84156ceba19a66a8f88be1f ]

In the past we've warned when ADJ_OFFSET was in progress, usually
caused by ntpd or some other time adjusting daemon running in non
steady sate, which can cause the skew calculations to be
incorrect.

Thus, this patch checks to see if the clock was being adjusted
when we fail so that we don't cause false negatives.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Miroslav Lichvar <mlichvar@redhat.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Stephen Boyd <sboyd@kernel.org>
Cc: Shuah Khan <shuah@kernel.org>
Cc: linux-kselftest@vger.kernel.org
Suggested-by: Miroslav Lichvar <mlichvar@redhat.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/tools/testing/selftests/timers/raw_skew.c b/tools/testing/selftests/timers/raw_skew.c
index 30906bfd9c1b582636a3ff85a5abd1d1bfb187a9..0ab937a17ebb325e141762d82fae006cacbf65f7 100644 (file)
--- a/tools/testing/selftests/timers/raw_skew.c
+++ b/tools/testing/selftests/timers/raw_skew.c
@@ -146,6 +146,11 @@ int main(int argv, char **argc)
        printf(" %lld.%i(act)", ppm/1000, abs((int)(ppm%1000)));
 
        if (llabs(eppm - ppm) > 1000) {
+               if (tx1.offset || tx2.offset ||
+                   tx1.freq != tx2.freq || tx1.tick != tx2.tick) {
+                       printf("        [SKIP]\n");
+                       return ksft_exit_skip("The clock was adjusted externally. Shutdown NTPd or other time sync daemons\n");
+               }
                printf("        [FAILED]\n");
                return ksft_exit_fail();
        }