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Subject[PATCH 2/2] powerpc: Implement arch_spin_is_locked() using arch_spin_value_unlocked()
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At a glance these are just the inverse of each other. The one subtlety
is that arch_spin_value_unlocked() takes the lock by value, rather than
as a pointer, which is important for the lockref code.

On the other hand arch_spin_is_locked() doesn't really care, so
implement it in terms of arch_spin_value_unlocked().

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
---
arch/powerpc/include/asm/spinlock.h | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/include/asm/spinlock.h b/arch/powerpc/include/asm/spinlock.h
index 5162f8c..a30ef69 100644
--- a/arch/powerpc/include/asm/spinlock.h
+++ b/arch/powerpc/include/asm/spinlock.h
@@ -28,8 +28,6 @@
#include <asm/synch.h>
#include <asm/ppc-opcode.h>

-#define arch_spin_is_locked(x) ((x)->slock != 0)
-
#ifdef CONFIG_PPC64
/* use 0x800000yy when locked, where yy == CPU number */
#ifdef __BIG_ENDIAN__
@@ -59,6 +57,11 @@ static __always_inline int arch_spin_value_unlocked(arch_spinlock_t lock)
return lock.slock == 0;
}

+static inline int arch_spin_is_locked(arch_spinlock_t *lock)
+{
+ return !arch_spin_value_unlocked(*lock);
+}
+
/*
* This returns the old value in the lock, so we succeeded
* in getting the lock if the return value is 0.
--
1.8.3.2


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