[PATCH] sched/clock: add dummy clear_sched_clock_stable stub function

[Paul Gortmaker]

In commit acb04058de49458010c44bb35b849d45113fd668 ("sched/clock:
Fix hotplug crash") the parisc code gained a call to this function.

However the prototype for it is within HAVE_UNSTABLE_SCHED_CLOCK
ifdef/endif.  That, combined with this:

  arch/parisc/Kconfig:    select HAVE_UNSTABLE_SCHED_CLOCK if SMP

means that parisc can have it either enabled or disabled, resulting
in the following build fail:

arch/parisc/kernel/setup.c:180:2: error: implicit declaration of
function 'clear_sched_clock_stable' [-Werror=implicit-function-declaration]

Add a no-op stub for the non-SMP case to prevent this.

Fixes: acb04058de49 ("sched/clock: Fix hotplug crash")
Cc: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Signed-off-by: Paul Gortmaker <paul.gortmaker@xxxxxxxxxxxxx>
---
 include/linux/sched.h | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/include/linux/sched.h b/include/linux/sched.h
index 43c4840c0485..c8a257fde056 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -2498,6 +2498,10 @@ static inline void sched_clock_tick(void)
 {
 }
 
+static inline void clear_sched_clock_stable(void)
+{
+}
+
 static inline void sched_clock_idle_sleep_event(void)
 {
 }
-- 
2.11.0