5  *  include/asm-s390/rwsem.h
11  *  Based on asm-alpha/semaphore.h and asm-i386/rwsem.h
23  * Readers increment by 1 and see a positive value when uncontended, negative
28  * be extended to 65534 by manually checking the whole MSW rather than relying
33  * This should be totally fair - if anything is waiting, a process that wants a
50 #define RWSEM_WAITING_BIAS	(-0x00010000)
55 #define RWSEM_WAITING_BIAS	(-0x0000000100000000L)
65 	signed long old, new;  in __down_read()
81 		: "=&d" (old), "=&d" (new), "=Q" (sem->count)  in __down_read()
82 		: "Q" (sem->count), "i" (RWSEM_ACTIVE_READ_BIAS)  in __down_read()
89  * trylock for reading -- returns 1 if successful, 0 if contention
93 	signed long old, new;  in __down_read_trylock()
113 		: "=&d" (old), "=&d" (new), "=Q" (sem->count)  in __down_read_trylock()
114 		: "Q" (sem->count), "i" (RWSEM_ACTIVE_READ_BIAS)  in __down_read_trylock()
124 	signed long old, new, tmp;  in __down_write_nested()
141 		: "=&d" (old), "=&d" (new), "=Q" (sem->count)  in __down_write_nested()
142 		: "Q" (sem->count), "m" (tmp)  in __down_write_nested()
154  * trylock for writing -- returns 1 if successful, 0 if contention
158 	signed long old;  in __down_write_trylock()
175 		: "=&d" (old), "=Q" (sem->count)  in __down_write_trylock()
176 		: "Q" (sem->count), "d" (RWSEM_ACTIVE_WRITE_BIAS)  in __down_write_trylock()
186 	signed long old, new;  in __up_read()
202 		: "=&d" (old), "=&d" (new), "=Q" (sem->count)  in __up_read()
203 		: "Q" (sem->count), "i" (-RWSEM_ACTIVE_READ_BIAS)  in __up_read()
215 	signed long old, new, tmp;  in __up_write()
217 	tmp = -RWSEM_ACTIVE_WRITE_BIAS;  in __up_write()
232 		: "=&d" (old), "=&d" (new), "=Q" (sem->count)  in __up_write()
233 		: "Q" (sem->count), "m" (tmp)  in __up_write()
245 	signed long old, new, tmp;  in __downgrade_write()
247 	tmp = -RWSEM_WAITING_BIAS;  in __downgrade_write()
262 		: "=&d" (old), "=&d" (new), "=Q" (sem->count)  in __downgrade_write()
263 		: "Q" (sem->count), "m" (tmp)  in __downgrade_write()
274 	signed long old, new;  in rwsem_atomic_add()
290 		: "=&d" (old), "=&d" (new), "=Q" (sem->count)  in rwsem_atomic_add()
291 		: "Q" (sem->count), "d" (delta)  in rwsem_atomic_add()
300 	signed long old, new;  in rwsem_atomic_update()
316 		: "=&d" (old), "=&d" (new), "=Q" (sem->count)  in rwsem_atomic_update()
317 		: "Q" (sem->count), "d" (delta)  in rwsem_atomic_update()