12  *   1) Upper half of semaphore count is a wait count (differs from rwsem
90 	atomic_long_set(&sem->count, LDSEM_UNLOCKED);  in __init_ldsem()
101 	long adjust, count;  in __ldsem_wake_readers()  local
105 	 * Note the 'active part' of the count is incremented by  in __ldsem_wake_readers()
109 	count = atomic_long_add_return(adjust, &sem->count);  in __ldsem_wake_readers()
111 		if (count > 0)  in __ldsem_wake_readers()
113 		if (atomic_long_try_cmpxchg(&sem->count, &count, count - adjust))  in __ldsem_wake_readers()
130 	 * Only wake this writer if the active part of the count can be  in writer_trylock()
133 	long count = atomic_long_add_return(LDSEM_ACTIVE_BIAS, &sem->count);  in writer_trylock()  local
135 		if ((count & LDSEM_ACTIVE_MASK) == LDSEM_ACTIVE_BIAS)  in writer_trylock()
137 		if (atomic_long_try_cmpxchg(&sem->count, &count, count - LDSEM_ACTIVE_BIAS))  in writer_trylock()
153  *   - the 'active part' of count (&0x0000ffff) reached 0 (but may have changed)
154  *   - the 'waiting part' of count (&0xffff0000) is -ve (and will still be so)
179 down_read_failed(struct ld_semaphore *sem, long count, long timeout)  in down_read_failed()  argument
188 	 * Try to reverse the lock attempt but if the count has changed  in down_read_failed()
193 		if (atomic_long_try_cmpxchg(&sem->count, &count, count + adjust)) {  in down_read_failed()
194 			count += adjust;  in down_read_failed()
197 		if (count > 0) {  in down_read_failed()
210 	if ((count & LDSEM_ACTIVE_MASK) == 0)  in down_read_failed()
236 			atomic_long_add_return(-LDSEM_WAIT_BIAS, &sem->count);  in down_read_failed()
252 down_write_failed(struct ld_semaphore *sem, long count, long timeout)  in down_write_failed()  argument
262 	 * Try to reverse the lock attempt but if the count has changed  in down_write_failed()
267 		if (atomic_long_try_cmpxchg(&sem->count, &count, count + adjust))  in down_write_failed()
269 		if ((count & LDSEM_ACTIVE_MASK) == LDSEM_ACTIVE_BIAS) {  in down_write_failed()
293 		atomic_long_add_return(-LDSEM_WAIT_BIAS, &sem->count);  in down_write_failed()
320 	long count;  in __ldsem_down_read_nested()  local
324 	count = atomic_long_add_return(LDSEM_READ_BIAS, &sem->count);  in __ldsem_down_read_nested()
325 	if (count <= 0) {  in __ldsem_down_read_nested()
327 		if (!down_read_failed(sem, count, timeout)) {  in __ldsem_down_read_nested()
339 	long count;  in __ldsem_down_write_nested()  local
343 	count = atomic_long_add_return(LDSEM_WRITE_BIAS, &sem->count);  in __ldsem_down_write_nested()
344 	if ((count & LDSEM_ACTIVE_MASK) != LDSEM_ACTIVE_BIAS) {  in __ldsem_down_write_nested()
346 		if (!down_write_failed(sem, count, timeout)) {  in __ldsem_down_write_nested()
370 	long count = atomic_long_read(&sem->count);  in ldsem_down_read_trylock()  local
372 	while (count >= 0) {  in ldsem_down_read_trylock()
373 		if (atomic_long_try_cmpxchg(&sem->count, &count, count + LDSEM_READ_BIAS)) {  in ldsem_down_read_trylock()
396 	long count = atomic_long_read(&sem->count);  in ldsem_down_write_trylock()  local
398 	while ((count & LDSEM_ACTIVE_MASK) == 0) {  in ldsem_down_write_trylock()
399 		if (atomic_long_try_cmpxchg(&sem->count, &count, count + LDSEM_WRITE_BIAS)) {  in ldsem_down_write_trylock()
413 	long count;  in ldsem_up_read()  local
417 	count = atomic_long_add_return(-LDSEM_READ_BIAS, &sem->count);  in ldsem_up_read()
418 	if (count < 0 && (count & LDSEM_ACTIVE_MASK) == 0)  in ldsem_up_read()
427 	long count;  in ldsem_up_write()  local
431 	count = atomic_long_add_return(-LDSEM_WRITE_BIAS, &sem->count);  in ldsem_up_write()
432 	if (count < 0)  in ldsem_up_write()