Re: [Xenomai] Xenomai/Cobalt on i7-3770S CPU

[Jan Kiszka <jan.kiszka@siemens.com>]

On 2016-06-09 19:41, Gilles Chanteperdrix wrote:
> On Thu, Jun 09, 2016 at 05:32:51PM +0000, Heinick, J Michael wrote:
>>
>> -----Original Message-----
>> From: Gilles Chanteperdrix [mailto:gilles.chanteperdrix@xenomai.org] 
>> Sent: Wednesday, June 08, 2016 3:39 PM
>> To: Heinick, J Michael
>> Cc: xenomai@xenomai.org
>> Subject: Re: [Xenomai] Xenomai/Cobalt on i7-3770S CPU
>>
>> On Wed, Jun 08, 2016 at 09:42:26AM +0000, Heinick, J Michael wrote:
>>>
>>> We currently have an RTDM driver that is running well on Xenomai/Cobalt 3.0.1 on 2 Dell computers with Core2 processors, but will hang (unresponsive mouse and keyboard, no discernable activity) an entire SuperLogics i7 computer with a Core i7-3770S processor (4 physical cores, 4 logical cores).  The hang occurs in the ioctl function at an rtdm_sem_down call that waits for the interrupt handler to signal the handling of an interrupt.  We suspect that we have a problem with our kernel build/installation configuration options.  We have attempted to configure the Core i7-3770S system so that Xenomai/Cobalt only uses 2 cores like the other 2 working Core2 computers, but the system still hangs (more detail on the results of our attempt is included beow).  Eventually, we would like to configu
>  re Xenomai/Cobalt to run on 4 cores of the i7 computer if possible.
>>>
>>> Any suggestions to help us make/install/configure Xenomai/Cobalt to run on the SuperLogics computer with the i7-3770S processor so that the rtdm_sem_down call in the RTDM driver does not hang the entire system would be appreciated.
>>
>> This sounds like an irq conflict: a device handled by an RTDM driver can not use the same irq line as a device handled by a plain Linux driver without modifying the plain Linux driver. See FAQ for solutions to that problem.
>>
>> -- 
>> 					    Gilles.
>> https://click-hack.org
>>
>>
>> Thanks for the reply, Gilles.
>>
>> Yes, there was a conflict on irq 16. We disabled the conflicting
>> component so that now our driver is the only one on irq 16, but
>> the i7-3770S system is still hanging. We know the interrupt
>> handler is receiving the interrupts and handling them without
>> hanging the i7 system. With the interrupts running at 20Hz, the
>> handler stores counts of the second and sub-second interrupts that
>> we can retrieve with a different ioctl call that does not wait for
>> an interrupt. The hang only occurs in the ioctl call at the wait
>> with the rtdm_sem_down call. The contents of selected files from
>> the /proc directory are included below.
> 
> 
> Could you post the simplest driver which generates this issue?
> 

And do you have CONFIG_XENO_OPT_DEBUG_COBALT enabled? That may reveal
sleeping issues in the driver design (common source of troubles).

Jan

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