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Date: Fri, 13 Feb 2004 14:37:39 +0000
From: Jamie Lokier <jamie@shareable.org>
To: linux-kernel@vger.kernel.org, Nick Piggin <piggin@cyberone.com.au>
Subject: Re: bug, or is it? - SCHED_RR and futex related
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References: <20040212205708.GA1679@ss1000.ms.mff.cuni.cz> <20040213101351.GB19072@ss1000.ms.mff.cuni.cz>
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Rudo Thomas wrote:
> I tracked it down to an infinite waiting in futex( ..., FUTEX_WAIT, 2, NULL).
> Can THIS hang the machine hard when running with SCHED_RR policy?

Do you mean that a task running with SCHED_RR calls futex( ...,
FUTEX_WAIT, 2, NULL), and there are no other SCHED_RR or SCHED_FIFO
tasks?

That cannot lock the machine hard.  When the futex call waits, the task sleeps.

-- Jamie