The best queue for RT_PREEMPT

The best queue for RT_PREEMPT

[Mauricio A. Araya L�pez]

Hi again,

I have some experience working on RTAI, and I am trying to do
something similar to a RT_FIFO. Which is the best method to have 
a FIFO queue between a real-time process and a non real-time process.
Maybe a pipe is enough, or msgget, or directly have a shared memory space,
etc... Any comment will be very welcome!

Thanks!

-- 
Mauricio Araya L. 
ACS-UTFSM Team Leader, cel: 0-81564903
Est. Magister en Ciencias de la Informatica UTFSM, Valparaiso, Chile
counter.li.org: #249395, http://www.inf.utfsm.cl/~maray 

Re: The best queue for RT_PREEMPT

[Remy Bohmer]

Hello,

I used a plain socket on localhost.
This works properly in our application, with little overhead, and does
not generate page-faults during RT-showtime.

Remy

2008/4/4, Mauricio A. Araya López <maray@inf.utfsm.cl>:
> Hi again,
>
>  I have some experience working on RTAI, and I am trying to do
>  something similar to a RT_FIFO. Which is the best method to have
>  a FIFO queue between a real-time process and a non real-time process.
>  Maybe a pipe is enough, or msgget, or directly have a shared memory space,
>  etc... Any comment will be very welcome!
>
>  Thanks!
>
>  --
>  Mauricio Araya L.
>  ACS-UTFSM Team Leader, cel: 0-81564903
>  Est. Magister en Ciencias de la Informatica UTFSM, Valparaiso, Chile
>  counter.li.org: #249395, http://www.inf.utfsm.cl/~maray
>
> --
>  To unsubscribe from this list: send the line "unsubscribe linux-rt-users" in
>  the body of a message to majordomo@vger.kernel.org
>  More majordomo info at  http://vger.kernel.org/majordomo-info.html
>
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Re: The best queue for RT_PREEMPT

[Robert Schwebel]

On Fri, Apr 04, 2008 at 02:49:41PM -0400, Mauricio A. Araya L?pez wrote:
> I have some experience working on RTAI, and I am trying to do
> something similar to a RT_FIFO. Which is the best method to have a
> FIFO queue between a real-time process and a non real-time process.
> Maybe a pipe is enough, or msgget, or directly have a shared memory
> space, etc... Any comment will be very welcome!

If your communication is message oriented, you can use POSIX Message
Queues. However, you can surely also use any other kind of other method,
as long as you don't lock shared ressources for too long.

Robert
-- 
 Dipl.-Ing. Robert Schwebel | http://www.pengutronix.de
 Pengutronix - Linux Solutions for Science and Industry
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Re: The best queue for RT_PREEMPT

[K.R. Foley]

Mauricio � wrote:
> Hi again,
> 
> I have some experience working on RTAI, and I am trying to do
> something similar to a RT_FIFO. Which is the best method to have 
> a FIFO queue between a real-time process and a non real-time process.
> Maybe a pipe is enough, or msgget, or directly have a shared memory space,
> etc... Any comment will be very welcome!
> 
> Thanks!
> 

Why not use a FIFO implemented as a circular buffer in shared memory?

-- 
    kr
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