Re: [Xenomai] RTDM-native brushup

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

On 2015-06-15 16:39, Michael Haberler wrote:
> ok, so tried to just get RTDM support and rtdmtest build as module and loadable without error, and that works
> 
> I did not bother fixing the sk_alloc() etc proto related changes for now
> Kernel was 3.2.0-4-rt-686-pae #1 SMP PREEMPT RT Debian 3.2.68-1+deb7u1 i686 GNU/Linux (RT-PREEMPT kernel in debian wheezy)
> 
> 
> this is where I am:  https://github.com/mhaberler/rtdm-native/commits/try1
> 
> do not expect my API transmogrifications to be correct, those were based on "maximum likelihood" guesstimates
> 
> 
> modprobe rtdm
> [31537.309416] starting RTDM services.
> 
> modprobe rtdmtest
> [31540.595708] __rtdmtest_init: registering device rttest0, err=251
> 
> mah@nwheezy:~/rtdm-native/ksrc/drivers/testing$ grep rttes /proc/devices 
> 251 rttest0
> 
> rmmod rtdmtest
> [31551.675050] rtdm_task_destroy: not allowed on user threads
> [31551.675053] rtdm_task_join_nrt: not allowed on user threads
> [31551.675056] __rtdmtest_exit: unregistering device rttest0
> 
> rmmod rtdm
> [31557.916463] stopping RTDM services.
> 
> the rtdm_task_destroy ff warning re user threads I cant make much sense of, I guess some underlying change

I would start checking if rtdm_task_has_magic(task) returns false, and
why. But I would also check the current kernel API /wrt kthread
management. There were some changes since then, and likely better
mappings are available now.

> 
> examples/rtdm-native/rtdmtest fails since /dev/rttest0 doesnt show up, I guess hotplug/udev update required - not sure how to force creation of the /dev entry otherwise

mknod?

> 
> I am unsure where to go from here - I looked over the xenomai-3 rtdm changes and I dont feel I'm qualified to track those

I suppose you have a use case / driver in mind. So it would probably be
best for you to fix / revise the native layer along that usage profile,
starting with init/cleanup functions, then extending to runtime services.

Jan

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