From 397bbf6dee50bb1f07cbdb464c41b0f5b7a85493 Mon Sep 17 00:00:00 2001 From: Prarit Bhargava Date: Fri, 22 Feb 2013 15:08:56 -0500 Subject: clocksource: Fix !CONFIG_CLOCKSOURCE_WATCHDOG compile If I explicitly disable the clocksource watchdog in the x86 Kconfig, the x86 kernel will not compile unless this is properly defined. Cc: John Stultz Cc: Thomas Gleixner Cc: x86@kernel.org Signed-off-by: Prarit Bhargava Signed-off-by: John Stultz --- kernel/time/clocksource.c | 1 + 1 file changed, 1 insertion(+) (limited to 'kernel') diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c index 50a8736..a2e72b8 100644 --- a/kernel/time/clocksource.c +++ b/kernel/time/clocksource.c @@ -479,6 +479,7 @@ static inline void clocksource_dequeue_watchdog(struct clocksource *cs) { } static inline void clocksource_resume_watchdog(void) { } static inline int __clocksource_watchdog_kthread(void) { return 0; } static bool clocksource_is_watchdog(struct clocksource *cs) { return false; } +void clocksource_mark_unstable(struct clocksource *cs) { } #endif /* CONFIG_CLOCKSOURCE_WATCHDOG */ -- cgit v1.1 From a97ad0c4b447a132a322cedc3a5f7fa4cab4b304 Mon Sep 17 00:00:00 2001 From: Miroslav Lichvar Date: Thu, 1 Aug 2013 19:31:35 +0200 Subject: ntp: Make periodic RTC update more reliable The current code requires that the scheduled update of the RTC happens in the closest tick to the half of the second. This seems to be difficult to achieve reliably. The scheduled work may be missing the target time by a tick or two and be constantly rescheduled every second. Relax the limit to 10 ticks. As a typical RTC drifts in the 11-minute update interval by several milliseconds, this shouldn't affect the overall accuracy of the RTC much. Signed-off-by: Miroslav Lichvar Signed-off-by: John Stultz --- kernel/time/ntp.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'kernel') diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c index 8f5b3b9..ab1fa7c 100644 --- a/kernel/time/ntp.c +++ b/kernel/time/ntp.c @@ -475,6 +475,7 @@ static void sync_cmos_clock(struct work_struct *work) * called as close as possible to 500 ms before the new second starts. * This code is run on a timer. If the clock is set, that timer * may not expire at the correct time. Thus, we adjust... + * We want the clock to be within a couple of ticks from the target. */ if (!ntp_synced()) { /* @@ -485,7 +486,7 @@ static void sync_cmos_clock(struct work_struct *work) } getnstimeofday(&now); - if (abs(now.tv_nsec - (NSEC_PER_SEC / 2)) <= tick_nsec / 2) { + if (abs(now.tv_nsec - (NSEC_PER_SEC / 2)) <= tick_nsec * 5) { struct timespec adjust = now; fail = -ENODEV; -- cgit v1.1