13 static inline unsigned __sl_cas(volatile unsigned *p, unsigned old, unsigned new)  in __sl_cas()  argument
17 		: "r"(old), "z"(p)  in __sl_cas()
54 	unsigned old;  in arch_read_lock()  local
55 	do old = rw->lock;  in arch_read_lock()
56 	while (!old || __sl_cas(&rw->lock, old, old-1) != old);  in arch_read_lock()
61 	unsigned old;  in arch_read_unlock()  local
62 	do old = rw->lock;  in arch_read_unlock()
63 	while (__sl_cas(&rw->lock, old, old+1) != old);  in arch_read_unlock()
78 	unsigned old;  in arch_read_trylock()  local
79 	do old = rw->lock;  in arch_read_trylock()
80 	while (old && __sl_cas(&rw->lock, old, old-1) != old);  in arch_read_trylock()
81 	return !!old;  in arch_read_trylock()