[PATCH powerpc ] Avoid debug_smp_processor_id() check in arch_spin_unlock_wait()

[Li Zhong]

Use local_paca directly in arch_spin_unlock_wait(), as all processors have the
same value for the field shared_proc, so we don't need care racy here.

Reported-by: Paul E. McKenney <paulmck at linux.vnet.ibm.com>
Signed-off-by: Li Zhong <zhong at linux.vnet.ibm.com>
---
 arch/powerpc/lib/locks.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/powerpc/lib/locks.c b/arch/powerpc/lib/locks.c
index bb7cfec..850bea6 100644
--- a/arch/powerpc/lib/locks.c
+++ b/arch/powerpc/lib/locks.c
@@ -72,7 +72,7 @@ void arch_spin_unlock_wait(arch_spinlock_t *lock)
 {
 	while (lock->slock) {
 		HMT_low();
-		if (SHARED_PROCESSOR)
+		if (local_paca->lppaca_ptr->shared_proc)
 			__spin_yield(lock);
 	}
 	HMT_medium();
-- 
1.7.9.5