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SubjectRe: [patch] Real-Time Preemption, -RT-2.6.9-rc4-mm1-U8
Scott Wood wrote:

>On Thu, Oct 21, 2004 at 06:15:00PM -0400, john cooper wrote:
>
>>Yes, but my concern was having to backoff in out-of-sequence
>>spinlock acquisition paths.
>>
>
>Out-of-sequence acquisition is a bug, unless the caller uses trylocks
>and handles backoff itself.
>
Understood -- we may be getting hung up on terminology here.

Rather the issue was whether the nondeterministic out-of-sequence
backoff could be pushed to a noncritical path. I believe so.
It is further likely a backoff would not be needed as the
a path acquiring a mutex's task-owned list lock during a
priority promotion scan shouldn't have reason to acquire any
task's mutex-owned list lock. The latter list would only need
to be locked at time of successful mutex acquisition/free.

-john

--
john.cooper@timesys.com

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