clockevents: Allow build w/o run-tine usage for migration purposes

Migration aid to allow preparatory patches which introduce not yet
used parts of clock events code.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>

diff --git a/kernel/time/Kconfig b/kernel/time/Kconfig
index f663511..8d53106 100644
--- a/kernel/time/Kconfig
+++ b/kernel/time/Kconfig
@@ -23,3 +23,8 @@
 	  hardware is not capable then this option only increases
 	  the size of the kernel image.
 
+config GENERIC_CLOCKEVENTS_BUILD
+	bool
+	default y
+	depends on GENERIC_CLOCKEVENTS || GENERIC_CLOCKEVENTS_MIGR
+
diff --git a/kernel/time/Makefile b/kernel/time/Makefile
index 99b6034..905b0b5 100644
--- a/kernel/time/Makefile
+++ b/kernel/time/Makefile
@@ -1,6 +1,6 @@
 obj-y += timekeeping.o ntp.o clocksource.o jiffies.o timer_list.o
 
-obj-$(CONFIG_GENERIC_CLOCKEVENTS)		+= clockevents.o
+obj-$(CONFIG_GENERIC_CLOCKEVENTS_BUILD)		+= clockevents.o
 obj-$(CONFIG_GENERIC_CLOCKEVENTS)		+= tick-common.o
 obj-$(CONFIG_GENERIC_CLOCKEVENTS_BROADCAST)	+= tick-broadcast.o
 obj-$(CONFIG_TICK_ONESHOT)			+= tick-oneshot.o
diff --git a/kernel/time/clockevents.c b/kernel/time/clockevents.c
index 41dd310..822beeb 100644
--- a/kernel/time/clockevents.c
+++ b/kernel/time/clockevents.c
@@ -194,6 +194,7 @@
 	local_irq_restore(flags);
 }
 
+#ifdef CONFIG_GENERIC_CLOCKEVENTS
 /**
  * clockevents_notify - notification about relevant events
  */
@@ -222,4 +223,4 @@
 	spin_unlock(&clockevents_lock);
 }
 EXPORT_SYMBOL_GPL(clockevents_notify);
-
+#endif