clocksource: add unregister function to disable unusable clocksources

On x86 the PIT might become an unusable clocksource. Add an unregister
function to provide a possibilty to remove the PIT from the list of
available clock sources.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 1 insertions, 0 deletions

diff --git a/include/linux/clocksource.h b/include/linux/clocksource.h
index 07b42153de24..85778a4b1209 100644
--- a/include/linux/clocksource.h
+++ b/include/linux/clocksource.h
@@ -215,6 +215,7 @@ static inline void clocksource_calculate_interval(struct clocksource *c,
 
 /* used to install a new clocksource */
 extern int clocksource_register(struct clocksource*);
+extern void clocksource_unregister(struct clocksource*);
 extern struct clocksource* clocksource_get_next(void);
 extern void clocksource_change_rating(struct clocksource *cs, int rating);
 extern void clocksource_resume(void);