From mboxrd@z Thu Jan  1 00:00:00 1970
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Date: Fri, 27 Aug 2010 14:32:20 +0200
From: Jan Kiszka <jan.kiszka@domain.hid>
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Subject: Re: [Xenomai-core] False positive XENO_BUGON(NUCLEUS,
 need_resched == 0)?
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To: Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>
Cc: xenomai-core <xenomai@xenomai.org>

Gilles Chanteperdrix wrote:
> Jan Kiszka wrote:
>> Hi,
>>
>> I'm hitting that bug check in __xnpod_schedule after
>> xnintr_clock_handler issued a xnpod_schedule like this:
>>
>> 	if (--sched->inesting == 0) {
>> 		__clrbits(sched->status, XNINIRQ);
>> 		xnpod_schedule();
>> 	}
>>
>> Either the assumption behind the bug check is no longer correct (no call
>> to xnpod_schedule() without a real need), or we should check for
>> __xnpod_test_resched(sched) in xnintr_clock_handler (but under nklock then).
>>
>> Comments?
> 
> You probably have a real bug. This BUG_ON means that the scheduler is
> about to switch context for real, whereas the resched bit is not set,
> which is wrong.

This happened over my 2.6.35 port - maybe some spurious IRQ enabling.
Debugging further...

Jan

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