sched: Cover the CONFIG_DEBUG_SPINLOCK_SLEEP off-case for __might_sleep()

Cover the off case for __might_sleep(), so that we avoid
#ifdefs in files that make use of it. Especially, this prepares
for the __might_sleep() pull up on cond_resched().

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1247725694-6082-3-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

include/linux/kernel.h

@@ -139,6 +139,7 @@ extern int _cond_resched(void);
 # define might_sleep() \
 	do { __might_sleep(__FILE__, __LINE__); might_resched(); } while (0)
 #else
+  static inline void __might_sleep(char *file, int line) { }
 # define might_sleep() do { might_resched(); } while (0)
 #endif
 

kernel/sched.c

@@ -6610,9 +6610,8 @@ static inline int should_resched(void)
 
 static void __cond_resched(void)
 {
-#ifdef CONFIG_DEBUG_SPINLOCK_SLEEP
 	__might_sleep(__FILE__, __LINE__);
-#endif
+
 	add_preempt_count(PREEMPT_ACTIVE);
 	schedule();
 	sub_preempt_count(PREEMPT_ACTIVE);