[PATCH 08/11] timekeeping: Provide internal function __ktime_get_real_seconds

From: John Stultz
Date: Fri Dec 18 2015 - 16:41:04 EST


From: DengChao <chao.deng@xxxxxxxxxx>

In order to fix Y2038 issues in the ntp code we will need replace
get_seconds() with ktime_get_real_seconds() but as the ntp code uses
the timekeeping lock which is also used by ktime_get_real_seconds(),
we need a version without locking.
Add a new function __ktime_get_real_seconds() in timekeeping to
do this.

Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Miroslav Lichvar <mlichvar@xxxxxxxxxx>
Cc: Prarit Bhargava <prarit@xxxxxxxxxx>
Cc: Richard Cochran <richardcochran@xxxxxxxxx>
Reviewed-by: John Stultz <john.stultz@xxxxxxxxxx>
Signed-off-by: DengChao <chao.deng@xxxxxxxxxx>
Signed-off-by: John Stultz <john.stultz@xxxxxxxxxx>
---
kernel/time/timekeeping.c | 13 +++++++++++++
kernel/time/timekeeping_internal.h | 2 ++
2 files changed, 15 insertions(+)

diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index d9249da..21cc239 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -845,6 +845,19 @@ time64_t ktime_get_real_seconds(void)
}
EXPORT_SYMBOL_GPL(ktime_get_real_seconds);

+/**
+ * __ktime_get_real_seconds - The same as ktime_get_real_seconds
+ * but without the sequence counter protect. This internal function
+ * is called just when timekeeping lock is already held.
+ */
+time64_t __ktime_get_real_seconds(void)
+{
+ struct timekeeper *tk = &tk_core.timekeeper;
+
+ return tk->xtime_sec;
+}
+
+
#ifdef CONFIG_NTP_PPS

/**
diff --git a/kernel/time/timekeeping_internal.h b/kernel/time/timekeeping_internal.h
index 4ea005a..e20466f 100644
--- a/kernel/time/timekeeping_internal.h
+++ b/kernel/time/timekeeping_internal.h
@@ -26,4 +26,6 @@ static inline cycle_t clocksource_delta(cycle_t now, cycle_t last, cycle_t mask)
}
#endif

+extern time64_t __ktime_get_real_seconds(void);
+
#endif /* _TIMEKEEPING_INTERNAL_H */
--
1.9.1

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