rwsem: Unify the duplicate rwsem_is_locked() inlines

Instead of having the same implementation in each architecture, move
it to linux/rwsem.h and remove the duplicates. It's unlikely that an
arch will ever implement something different, but we can deal with
that when it happens.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Matt Turner <mattst88@gmail.com>
Acked-by: Tony Luck <tony.luck@intel.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Acked-by: David Miller <davem@davemloft.net>
Cc: Chris Zankel <chris@zankel.net>
LKML-Reference: <20110126195833.876773757@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

arch/alpha/include/asm/rwsem.h

@@ -224,10 +224,5 @@ static inline long rwsem_atomic_update(long val, struct rw_semaphore *sem)
 #endif
 }
 
-static inline int rwsem_is_locked(struct rw_semaphore *sem)
-{
-	return (sem->count != 0);
-}
-
 #endif /* __KERNEL__ */
 #endif /* _ALPHA_RWSEM_H */

arch/ia64/include/asm/rwsem.h

@@ -147,9 +147,4 @@ __downgrade_write (struct rw_semaphore *sem)
 #define rwsem_atomic_add(delta, sem)	atomic64_add(delta, (atomic64_t *)(&(sem)->count))
 #define rwsem_atomic_update(delta, sem)	atomic64_add_return(delta, (atomic64_t *)(&(sem)->count))
 
-static inline int rwsem_is_locked(struct rw_semaphore *sem)
-{
-	return (sem->count != 0);
-}
-
 #endif /* _ASM_IA64_RWSEM_H */

arch/powerpc/include/asm/rwsem.h

@@ -133,10 +133,5 @@ static inline long rwsem_atomic_update(long delta, struct rw_semaphore *sem)
 	return atomic_long_add_return(delta, (atomic_long_t *)&sem->count);
 }
 
-static inline int rwsem_is_locked(struct rw_semaphore *sem)
-{
-	return sem->count != 0;
-}
-
 #endif	/* __KERNEL__ */
 #endif	/* _ASM_POWERPC_RWSEM_H */

arch/s390/include/asm/rwsem.h

@@ -325,10 +325,5 @@ static inline long rwsem_atomic_update(long delta, struct rw_semaphore *sem)
 	return new;
 }
 
-static inline int rwsem_is_locked(struct rw_semaphore *sem)
-{
-	return (sem->count != 0);
-}
-
 #endif /* __KERNEL__ */
 #endif /* _S390_RWSEM_H */

arch/sh/include/asm/rwsem.h

@@ -133,10 +133,5 @@ static inline int rwsem_atomic_update(int delta, struct rw_semaphore *sem)
 	return atomic_add_return(delta, (atomic_t *)(&sem->count));
 }
 
-static inline int rwsem_is_locked(struct rw_semaphore *sem)
-{
-	return (sem->count != 0);
-}
-
 #endif /* __KERNEL__ */
 #endif /* _ASM_SH_RWSEM_H */

arch/sparc/include/asm/rwsem.h

@@ -124,11 +124,6 @@ static inline long rwsem_atomic_update(long delta, struct rw_semaphore *sem)
 	return atomic64_add_return(delta, (atomic64_t *)(&sem->count));
 }
 
-static inline int rwsem_is_locked(struct rw_semaphore *sem)
-{
-	return (sem->count != 0);
-}
-
 #endif /* __KERNEL__ */
 
 #endif /* _SPARC64_RWSEM_H */

arch/x86/include/asm/rwsem.h

@@ -222,10 +222,5 @@ static inline long rwsem_atomic_update(long delta, struct rw_semaphore *sem)
 	return tmp + delta;
 }
 
-static inline int rwsem_is_locked(struct rw_semaphore *sem)
-{
-	return (sem->count != 0);
-}
-
 #endif /* __KERNEL__ */
 #endif /* _ASM_X86_RWSEM_H */

arch/xtensa/include/asm/rwsem.h

@@ -133,9 +133,4 @@ static inline int rwsem_atomic_update(int delta, struct rw_semaphore *sem)
 	return atomic_add_return(delta, (atomic_t *)(&sem->count));
 }
 
-static inline int rwsem_is_locked(struct rw_semaphore *sem)
-{
-	return (sem->count != 0);
-}
-
 #endif	/* _XTENSA_RWSEM_H */

include/linux/rwsem.h

@@ -34,6 +34,13 @@ struct rw_semaphore {
 
 /* Include the arch specific part */
 #include <asm/rwsem.h>
+
+/* In all implementations count != 0 means locked */
+static inline int rwsem_is_locked(struct rw_semaphore *sem)
+{
+	return sem->count != 0;
+}
+
 #endif
 
 /* Common initializer macros and functions */