[SPARC64]: Simplify asm/rwsem.h slightly.

rwsem_atomic_update and rwsem_atomic_add can be implemented
straightly using atomic_*() routines.

Also, rwsem_cmpxchgw() is totally unused, kill it.

Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/asm-sparc64/rwsem.h b/include/asm-sparc64/rwsem.h
index a1cc94f95984039f4e416686ca5a427964a6bc95..4568ee4022df0f957fb6f42dac4e9390d579a4fa 100644 (file)
--- a/include/asm-sparc64/rwsem.h
+++ b/include/asm-sparc64/rwsem.h
@@ -46,54 +46,14 @@ extern void __up_read(struct rw_semaphore *sem);
 extern void __up_write(struct rw_semaphore *sem);
 extern void __downgrade_write(struct rw_semaphore *sem);
 
-static __inline__ int rwsem_atomic_update(int delta, struct rw_semaphore *sem)
+static inline int rwsem_atomic_update(int delta, struct rw_semaphore *sem)
 {
-       int tmp = delta;
-
-       __asm__ __volatile__(
-               "1:\tlduw       [%2], %%g1\n\t"
-               "add            %%g1, %1, %%g7\n\t"
-               "cas            [%2], %%g1, %%g7\n\t"
-               "cmp            %%g1, %%g7\n\t"
-               "membar         #StoreLoad | #StoreStore\n\t"
-               "bne,pn         %%icc, 1b\n\t"
-               " nop\n\t"
-               "mov            %%g7, %0\n\t"
-               : "=&r" (tmp)
-               : "0" (tmp), "r" (sem)
-               : "g1", "g7", "memory", "cc");
-
-       return tmp + delta;
-}
-
-#define rwsem_atomic_add rwsem_atomic_update
-
-static __inline__ __u16 rwsem_cmpxchgw(struct rw_semaphore *sem, __u16 __old, __u16 __new)
-{
-       u32 old = (sem->count & 0xffff0000) | (u32) __old;
-       u32 new = (old & 0xffff0000) | (u32) __new;
-       u32 prev;
-
-again:
-       __asm__ __volatile__("cas       [%2], %3, %0\n\t"
-                            "membar    #StoreLoad | #StoreStore"
-                            : "=&r" (prev)
-                            : "0" (new), "r" (sem), "r" (old)
-                            : "memory");
-
-       /* To give the same semantics as x86 cmpxchgw, keep trying
-        * if only the upper 16-bits changed.
-        */
-       if (prev != old &&
-           ((prev & 0xffff) == (old & 0xffff)))
-               goto again;
-
-       return prev & 0xffff;
+       return atomic_add_return(delta, (atomic_t *)(&sem->count));
 }
 
-static __inline__ signed long rwsem_cmpxchg(struct rw_semaphore *sem, signed long old, signed long new)
+static inline void rwsem_atomic_add(int delta, struct rw_semaphore *sem)
 {
-       return cmpxchg(&sem->count,old,new);
+       atomic_add(delta, (atomic_t *)(&sem->count));
 }
 
 #endif /* __KERNEL__ */