powerpc/spinlocks: Rename SPLPAR-only spinlocks

The __rw_yield and __spin_yield locks only pertain to SPLPAR mode.
Rename them to make this relationship obvious.
Signed-off-by: Christopher M. Riedl <cmr@informatik.wtf>
Reviewed-by: Andrew Donnellan <ajd@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190813031314.1828-3-cmr@informatik.wtf

arch/powerpc/include/asm/spinlock.h

@@ -101,8 +101,10 @@ static inline int arch_spin_trylock(arch_spinlock_t *lock)
 
 #if defined(CONFIG_PPC_SPLPAR)
 /* We only yield to the hypervisor if we are in shared processor mode */
-extern void __spin_yield(arch_spinlock_t *lock);
-extern void __rw_yield(arch_rwlock_t *lock);
+void splpar_spin_yield(arch_spinlock_t *lock);
+void splpar_rw_yield(arch_rwlock_t *lock);
+#define __spin_yield(x) splpar_spin_yield(x)
+#define __rw_yield(x) splpar_rw_yield(x)
 #else /* SPLPAR */
 #define __spin_yield(x)	barrier()
 #define __rw_yield(x)	barrier()

arch/powerpc/lib/locks.c

@@ -18,7 +18,7 @@
 #include <asm/hvcall.h>
 #include <asm/smp.h>
 
-void __spin_yield(arch_spinlock_t *lock)
+void splpar_spin_yield(arch_spinlock_t *lock)
 {
 	unsigned int lock_value, holder_cpu, yield_count;
 
@@ -36,14 +36,14 @@ void __spin_yield(arch_spinlock_t *lock)
 	plpar_hcall_norets(H_CONFER,
 		get_hard_smp_processor_id(holder_cpu), yield_count);
 }
-EXPORT_SYMBOL_GPL(__spin_yield);
+EXPORT_SYMBOL_GPL(splpar_spin_yield);
 
 /*
  * Waiting for a read lock or a write lock on a rwlock...
  * This turns out to be the same for read and write locks, since
  * we only know the holder if it is write-locked.
  */
-void __rw_yield(arch_rwlock_t *rw)
+void splpar_rw_yield(arch_rwlock_t *rw)
 {
 	int lock_value;
 	unsigned int holder_cpu, yield_count;