timekeeping: Make jiffies_lock internal

Nothing outside of the timekeeping core needs that lock.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NJohn Stultz <john.stultz@linaro.org>

include/linux/jiffies.h

@@ -75,7 +75,6 @@ extern int register_refined_jiffies(long clock_tick_rate);
  */
 extern u64 __jiffy_data jiffies_64;
 extern unsigned long volatile __jiffy_data jiffies;
-extern seqlock_t jiffies_lock;
 
 #if (BITS_PER_LONG < 64)
 u64 get_jiffies_64(void);

kernel/time/tick-internal.h

@@ -4,6 +4,8 @@
 #include <linux/hrtimer.h>
 #include <linux/tick.h>
 
+extern seqlock_t jiffies_lock;
+
 #ifdef CONFIG_GENERIC_CLOCKEVENTS_BUILD
 
 #define TICK_DO_TIMER_NONE	-1

kernel/time/timekeeping.c

@@ -23,6 +23,7 @@
 #include <linux/stop_machine.h>
 #include <linux/pvclock_gtod.h>
 
+#include "tick-internal.h"
 
 static struct timekeeper timekeeper;