[SPARC64]: More fully work around Spitfire Errata 51.
It appears that a memory barrier soon after a mispredicted
branch, not just in the delay slot, can cause the hang
condition of this cpu errata.
So move them out-of-line, and explicitly put them into
a "branch always, predict taken" delay slot which should
fully kill this problem.
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/asm-sparc64/spinlock.h b/include/asm-sparc64/spinlock.h
index d265bf6..a02c437 100644
--- a/include/asm-sparc64/spinlock.h
+++ b/include/asm-sparc64/spinlock.h
@@ -43,7 +43,7 @@
#define spin_is_locked(lp) ((lp)->lock != 0)
#define spin_unlock_wait(lp) \
-do { membar("#LoadLoad"); \
+do { rmb(); \
} while((lp)->lock)
static inline void _raw_spin_lock(spinlock_t *lock)
@@ -129,7 +129,7 @@
#define spin_is_locked(__lock) ((__lock)->lock != 0)
#define spin_unlock_wait(__lock) \
do { \
- membar("#LoadLoad"); \
+ rmb(); \
} while((__lock)->lock)
extern void _do_spin_lock(spinlock_t *lock, char *str, unsigned long caller);