RE: [PATCH] Priority Lists for the RT mutex

["Perez-Gonzalez, Inaky" <inaky.perez-gonzalez@intel.com>]

>From: Ingo Molnar [mailto:mingo@elte.hu]
>
>* Perez-Gonzalez, Inaky <inaky.perez-gonzalez@intel.com> wrote:
>
>> >OTOH, deadlock detection is another issue. It's quite expensive and
i'm
>> >not sure we want to make it a runtime thing. But for fusyn's
deadlock
>> >detection and safe teardown on owner-exit is a must-have i suspect?
>>
>> Not really. Deadlock check is needed on PI, so it can be done at the
>> same time (you have to walk the chain anyway). In any other case, it
>> is an option you can request (or not).
>
>well, i was talking about the mutex code in PREEMPT_RT. There deadlock
>detection is an optional debug feature. You dont _have_ to do deadlock
>detection for the kernel's locks, and there's a difference in
>performance.

Big mouth'o mine :-| 

Let me re-phrase then: it is a must have only on PI, to make sure 
you don't have a loop when doing it. Maybe is a consequence of the
algorithm I chose. -However- it should be possible to disable it
in cases where you are reasonably sure it won't happen (such as
kernel code). In any case, AFAIR, I still did not implement it.

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-- Inaky 
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