Re: [Xenomai-help] Sleep in rtdm driver

[Jan Kiszka <jan.kiszka@domain.hid>]

robert165 wrote:
> Hi everyone!
> 
> I'm writing a gpio driver in RTDM. I start it with the demo "Hard real time RTDM driver skeleton v1.1" of Jan Kiszka.
> If I used rtdm_task_sleep in rt_ioctrl  function,  it return that "Xenomai: assertion failed at kernel/xenomai/skins/rtdm/drvlib.c:372 (!xnpod_unblockable_p())"  when running.
> It is said that rtdm_task_sleep can be called from Kernel-based task. Why I can't use it in my driver. Optionally, I can do this in user-space by periodic calling the driver, but it seems slower than in kernel space.

The terms "kernel-based task" or "user space task" can be misleading.
This services requires a real-time task context. That can either be a
kernel-based *RT* task or a Xenomai shadow (aka *RT*) task in user space
that has invoked some driver service, and that driver can then call
rtdm_task_sleep on behalf of the user space task.

Blocking RTDM service *must not* be called by ordinary Linux kernel
threads or on behalf of ordinary (non-shadowed) Linux user space
threads. That's why the assertion failed for you.

HTH,
Jan

-- 
Siemens AG, Corporate Technology, CT T DE IT 1
Corporate Competence Center Embedded Linux