Readiness for Integrated Modular Avionics?
Thomas.Doerfler at embedded-brains.de
Fri Oct 20 13:11:54 UTC 2006
I think you are mixing two terms related to memory accesses:
RTEMS supports various standard APIs including the functions malloc,
free and friends to support dynamic memory allocation. This is a
convenient way to allow all tasks to fulfill their memory requirements.
But in current implementations there is no mechanism to avoid one task
to access variables and memory regions of another task. This would
typically be implemented using a MMU, but has some disadvantages aswell.
So, wikipedia is right, all RTEMS tasks execute in a signle process
Christian, Martin, OPEE45 schrieb:
> I'm evaluating different Open Source RTOS for use with Integrated
> Modular Avionics and I'd like to get some information about the RTMES
> architecture. I'm especially concerned with the time an space
> partitioning, which is requiring support for CPU protection modes and
> MMUs. The only information I found, is on Wikipedia stating: "RTEMS does
> not provide any form of memory management or processes. In POSIX
> terminology, it implements a single process, multithreaded environment."
> But I found already evidence that the former statement is not true
> (anymore), since there where some references to malloc/free calls in
> this mailing list.
> I tried to find the information myself, but so far without success - at
> least nothing I could cite in a Diplom Thesis. And at this stage I don't
> want to go into the code. Thus I hope you'll answer my questions or
> better point me to some papers I could cite.
> rtems-users mailing list
> rtems-users at rtems.com
embedded brains GmbH
Thomas Doerfler Obere Lagerstr. 30
D-82178 Puchheim Germany
Tel. : +49-89-18 90 80 79-2
Fax : +49-89-18 90 80 79-9
email: Thomas.Doerfler at embedded-brains.de
PGP public key available on request
More information about the users