Siddhesh Poyarekar c30e8edf7c Unlock mutex before going back to waiting for PI mutexes ...

[BZ #14417]
A futex call with FUTEX_WAIT_REQUEUE_PI returns with the mutex locked
on success.  If such a successful thread is pipped to the cond_lock by
another spuriously woken waiter, it could be sent back to wait on the
futex with the mutex lock held, thus causing a deadlock.  So it is
necessary that the thread relinquishes the mutex before going back to
sleep.

2012-10-05 18:52:36 +05:30

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linux

Unlock mutex before going back to waiting for PI mutexes

2012-10-05 18:52:36 +05:30