From: Michael Ellerman <mpe@ellerman.id.au>
Date: Wed, 15 Jan 2014 07:14:29 +0000 (+1100)
Subject: powerpc: Implement arch_spin_is_locked() using arch_spin_value_unlocked()
X-Git-Tag: submit/tizen/20160607.132125~5241^2
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=7179ba52889bef7e5e23f72908270e1ab2b7fc6f;p=sdk%2Femulator%2Femulator-kernel.git

powerpc: Implement arch_spin_is_locked() using arch_spin_value_unlocked()

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>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
---

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.