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Date: Wed, 27 Aug 2008 17:28:01 +0200
From: Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>
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Subject: Re: [Xenomai-core] [RFC][PATCH 2/3] Switch to handle-based fast
	mutex owners
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To: Jan Kiszka <jan.kiszka@domain.hid>
Cc: xenomai-core <xenomai@xenomai.org>

Jan Kiszka wrote:
> Gilles Chanteperdrix wrote:
>> Jan Kiszka wrote:
>>> +	xnarch_atomic_set(mutex->owner,
>>> +		 	  set_claimed(xnthread_handle(owner),
>>> +				      xnsynch_nsleepers(&mutex->synchbase)));
>> Ok. I think you have spotted a bug here. This should be mutex->sleepers
>> instead of xnsynch_nsleepers.
> 
> BTW, why do you need to track sleepers separately in POSIX? Native
> doesn't do so, e.g.

Because of the "syscall-needed-when-unlocking-stolen-mutex" issue I
already explained (sleepers - xnsynch_nsleepers is precisely the count
of pending threads which have been awake then robbed the mutex).

-- 
                                                 Gilles.