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Subject: Re: [linux-audio-dev] Re: [announce] [patch] Voluntary Kernel
	Preemption Patch
From: Eric St-Laurent <ericstl34@sympatico.ca>
To: Ingo Molnar <mingo@elte.hu>
Cc: Bill Huey <bhuey@lnxw.com>, Scott Wood <scott@timesys.com>,
       Andrew Morton <akpm@osdl.org>, linux-audio-dev@music.columbia.edu,
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On Wed, 2004-07-28 at 02:45, Ingo Molnar wrote:
> i'd agree with turning most of the finegrained per-task (non-irq-safe)
> spinlocks into mutexes (or spin-mutexes). But the central locks that an
> RT task would likely hit need to remain spinlocks i believe.
> 
> plus there are central mutexes too that are in 'hiding' currently but
> could cause latencies just as much.

Here are patches that convert spinlocks into kernel mutexes with
priority inheritance.  They look reasonably clean, and might be
interesting to try.

http://inf3-www.informatik.unibw-muenchen.de/research/linux/mutex/mutex.html


Best regards,

Eric St-Laurent