From: Alexander Sverdlin <alexander.sverd...@nokia.com>

Flushing the write buffer brings aroung 10% performace on the tight
uncontended spinlock loops on Octeon. Refer to commit 500c2e1fdbcc
("MIPS: Optimize spinlocks.").

Signed-off-by: Alexander Sverdlin <alexander.sverd...@nokia.com>
---
 arch/mips/include/asm/spinlock.h | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/arch/mips/include/asm/spinlock.h b/arch/mips/include/asm/spinlock.h
index 8a88eb2..0a707f3 100644
--- a/arch/mips/include/asm/spinlock.h
+++ b/arch/mips/include/asm/spinlock.h
@@ -24,6 +24,9 @@ static inline void queued_spin_unlock(struct qspinlock *lock)
        /* This could be optimised with ARCH_HAS_MMIOWB */
        mmiowb();
        smp_store_release(&lock->locked, 0);
+#ifdef CONFIG_CPU_CAVIUM_OCTEON
+       nudge_writes();
+#endif
 }
 
 #include <asm/qspinlock.h>
-- 
2.10.2

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