[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>

1 files changed, 4 insertions, 44 deletions

diff --git a/include/asm-sparc64/rwsem.h b/include/asm-sparc64/rwsem.h
index a1cc94f95984..4568ee4022df 100644
--- 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__ */