Commit e40d3709 authored by John Stultz's avatar John Stultz Committed by Thomas Gleixner
Browse files

selftests/timers: Improve skew_consistency by testing with other clockids 



Lei Chen reported a bug with CLOCK_MONOTONIC_COARSE having inconsistencies
when NTP is adjusting the clock frequency.

This has gone seemingly undetected for ~15 years, illustrating a clear gap
in our testing.

The skew_consistency test is intended to catch this sort of problem, but
was focused on only evaluating CLOCK_MONOTONIC, and thus missed the problem
on CLOCK_MONOTONIC_COARSE.

So adjust the test to run with all clockids for 60 seconds each instead of
10 minutes with just CLOCK_MONOTONIC.

Reported-by: default avatarLei Chen <lei.chen@smartx.com>
Signed-off-by: default avatarJohn Stultz <jstultz@google.com>
Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20250320200306.1712599-2-jstultz@google.com
Closes: https://lore.kernel.org/lkml/20250310030004.3705801-1-lei.chen@smartx.com/
parent 757b000f

tools/testing/selftests/timers/skew_consistency.c

+1 −1
Original line number Diff line number Diff line
@@ -47,7 +47,7 @@ int main(int argc, char **argv) 


	pid = fork();

	if (!pid)

		return system("./inconsistency-check -c 1 -t 600");

		return system("./inconsistency-check -t 60");



	ppm = 500;

	ret = 0;