[linux-yocto] [PATCH 3/6] timekeeping: Provide internal function __ktime_get_real_seconds

[jonathan.yong at intel.com]

From: DengChao <chao.deng at linaro.org>

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.

Reviewed-by: John Stultz <john.stultz at linaro.org>
Signed-off-by: DengChao <chao.deng at linaro.org>
Signed-off-by: John Stultz <john.stultz at linaro.org>
(cherry picked from commit dee3665416a8553279d10b62b5e62685cbe5daa8)
Signed-off-by: Yong, Jonathan <jonathan.yong at intel.com>
---
 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 80ed299..898911a 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -862,6 +862,19 @@ 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 */
-- 
2.7.3