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futex: priority wakeup miss ordering

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To: Pierre Peiffer <pierre.peiffer@...>
Cc: <linux-kernel@...>
Date: Wednesday, May 7, 2008 - 5:22 pm

from commit ec92d08292d3e9b0823eba138a4564d2d39f25c7

The wakeup ordering should be in priority order. However if the priority
of a task is modified while it's waiting on the futex you will get an
out of order wakeup.

If you use a priority inheriting mutex this is correct. It's because the
rtmutex hooks into sched_setscheduler to catch any priority changes,
then re-queues with the new priority.. But the futex doesn't have this
hook.

Was this intentionally left out of this priority wake up patch? I
thought I would let you know in case you had a specific reason for not
handling this.. 

Daniel

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Messages in current thread:
futex: priority wakeup miss ordering, Daniel Walker, (Wed May 7, 5:22 pm)
Re: futex: priority wakeup miss ordering, Thomas Gleixner, (Thu May 8, 6:06 am)
Re: futex: priority wakeup miss ordering, Daniel Walker, (Thu May 8, 12:28 pm)
Re: futex: priority wakeup miss ordering, Andrew Morton, (Thu May 8, 4:25 am)
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