2016-08-19 5:11 GMT+08:00 Waiman Long [off-list ref]:

When the count value is in between 0 and RWSEM_WAITING_BIAS, there
are 2 possibilities.
Either a writer is present and there is no waiter

count = 0xffff0001

or there are waiters and readers. There is no easy way to

count = 0xffff000X

However, RWSEM_WAITING_BIAS is equal to 0xffff0000, so both these two
cases are beyond RWSEM_WAITING_BIAS, right?

Regards,
Wanpeng Li