ACK: [PATCH][SRU][B] selftest: timers: Tweak raw_skew to SKIP when ADJ_OFFSET/other clock adjustments are in progress

[Kleber Souza]

On 2/1/19 6:45 PM, Dan Streetman wrote:
> From: John Stultz <john.stultz at linaro.org>
>
> BugLink: https://bugs.launchpad.net/bugs/1811194
>
> 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 at linutronix.de>
> Cc: Ingo Molnar <mingo at kernel.org>
> Cc: Miroslav Lichvar <mlichvar at redhat.com>
> Cc: Richard Cochran <richardcochran at gmail.com>
> Cc: Prarit Bhargava <prarit at redhat.com>
> Cc: Stephen Boyd <sboyd at kernel.org>
> Cc: Shuah Khan <shuah at kernel.org>
> Cc: linux-kselftest at vger.kernel.org
> Suggested-by: Miroslav Lichvar <mlichvar at redhat.com>
> Signed-off-by: John Stultz <john.stultz at linaro.org>
> ---
> v2: Widened the checks to look for other clock adjustments that
>     could happen, as suggested by Miroslav
> v3: Fixed up commit message
>
> Signed-off-by: Dan Streetman <ddstreet at canonical.com>
> (cherry-picked from upstream 1416270f4a1ae83ea84156ceba19a66a8f88be1f)


Acked-by: Kleber Sacilotto de Souza <kleber.souza at canonical.com>


> ---
>  tools/testing/selftests/timers/raw_skew.c | 5 +++++
>  1 file changed, 5 insertions(+)
>
> diff --git a/tools/testing/selftests/timers/raw_skew.c b/tools/testing/selftests/timers/raw_skew.c
> index ca6cd146aafe..dcf73c5dab6e 100644
> --- a/tools/testing/selftests/timers/raw_skew.c
> +++ b/tools/testing/selftests/timers/raw_skew.c
> @@ -134,6 +134,11 @@ 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();
>  	}