K 10
svn:author
V 3
kib
K 8
svn:date
V 27
2015-02-25T16:12:56.305595Z
K 7
svn:log
V 626
When unlocking a contested PI pthread mutex, if the queue of waiters
is empty, look up the umtx_pi and disown it if the current thread owns it.
This can happen if a signal or timeout removed the last waiter from
the queue, but there is still a thread in do_lock_pi() holding a reference
on the umtx_pi.  The unlocking thread might not own the umtx_pi in this case,
but if it does, it must disown it to keep the ownership consistent between
the umtx_pi and the umutex.

Submitted by:	Eric van Gyzen <eric_van_gyzen@dell.com>
	with advice from: Elliott Rabe and Jim Muchow, also at Dell Inc.
Obtained from:	Dell Inc.
PR:	198914

END