Logging/printf's in RT env
Rene Wittmann
Rene.B.Wittmann at informatik.stud.uni-erlangen.de
Thu Aug 4 13:45:12 CEST 2005
Hi,
I have also the problem that I want to output some of my symbols+values
during the execution of my application.
Furthermore I'm working in the RT scheduling mode (with APIC one shot
mode).
I have three timeslices:
1. mandatory
2. optional
3. "mandatory" (if part of optional was executed)
The preempter recognizes timeslice overruns and sets a
global variable, the working thread checks this variable and therefore
knows about those "events".
This works fine if my priorites are set to 50,30,50,
but fails after a few periods with a pagefault if setting the priorities to
200,190,200.
In each part I use some calls to LOG() to output a few things I'm
interested in. If I leave out those LOG()-calls, it works also with the
high priorites (200,190,200).
So I assume, there's a LOG-buffer overflow (as the LOG priority is not
that high)?
Could I prevent this by using printf instead of LOG or is LOG just a
kind of macro for printf?
Regards,
Rene
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