Re: [rtl] printk inside rt process

[Chris Albertson <chris@topdog.pas1.logicon.com>]

Jochen.Kupper @bacchus.pc1.uni-duesseldorf.de wrote:
> 
> Dear All,
> 
> am I right that you cannot use any of the standard kernel functions (like
> printk) from inside an real-time process/function ?
> 
> So what are you doing to inform about error conditions, that shall be some kind
> of informal help to the user, not just aborting or ignoring the problem ?
> Something like printk could do.
>

You can use printk within the module initialization put not in a
RT task.

What I do is use FIFO #2 for messages.  I write debug and status
messages to the FIFO from an RT task and have a user process that
reads and routes messages from the fifo.  I have formalized it a
little by placing the messages in a structure and send some flags
along with the test.  You could however just send strings and
use "cat" for your user process.

This is also how I send commands to my RT task.  I have one RT task
that reads commands from a fifo and set sets some global variables
based on those commands.  The "true" RT tasks the ones that run in
fast loops then see the globals.

One command I have is "dump global memory to the fifo"  This helps
with debugging
-- 
--Chris Albertson

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--- [rtl] ---
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