[Xenomai-help] Xenomai on kernel 3.x and x86

[Xenomai-help] Xenomai on kernel 3.x and x86

[Leopold Palomo-Avellaneda]

Hi,

sorry if the question it's obvious but I have not understood the information 
that I have found. I have read the roadmap of Xenomai [1] and it's not clear 
to me what should I have to do if I would want to use xenomai in a kernel 
3.x.

As far as I understand the idea it's to go to Xenomai 3 with the prempt patch 
or a co-kernel option. Then xenomai will be the interface to the realtime 
kernel. From the user point of view, no matter if xenomai will use the rt-
preemt or the co-kernel option. Also, the driver option will be the rtdm.

But I don't understand if the Adeos patch will survive (at least in x86) or 
what will happen. I understand that the co-kernel option is the same that we 
have now (2.6) with the adeos patch, but I have not be able to find an Adeos 
patch for a x86 platform in a 3.x kernel.

Please, someone could clarify this.

Thanks in advance,

Leo



[1] http://www.xenomai.org/index.php/Xenomai:Roadmap

-- 
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Linux User 152692
Catalonia

Re: [Xenomai-help] Xenomai on kernel 3.x and x86

[Philippe Gerum]

On 05/14/2012 09:45 AM, Leopold Palomo-Avellaneda wrote:
> Hi,
>
> sorry if the question it's obvious but I have not understood the information
> that I have found. I have read the roadmap of Xenomai [1] and it's not clear
> to me what should I have to do if I would want to use xenomai in a kernel
> 3.x.
>
> As far as I understand the idea it's to go to Xenomai 3 with the prempt patch
> or a co-kernel option. Then xenomai will be the interface to the realtime
> kernel. From the user point of view, no matter if xenomai will use the rt-
> preemt or the co-kernel option. Also, the driver option will be the rtdm.
>
> But I don't understand if the Adeos patch will survive (at least in x86) or
> what will happen. I understand that the co-kernel option is the same that we
> have now (2.6) with the adeos patch, but I have not be able to find an Adeos
> patch for a x86 platform in a 3.x kernel.

The interrupt pipeline will be maintained for running the co-kernel 
incarnation of Xenomai 3, and for updating the 2.6.x maintenance branch 
as well. To run 3.2 kernels and above, using Xenomai 2.6.1 or later will 
be a requirement.

There is an upcoming patch for linux 3.2, which is the first of the new 
pipeline "core" series, a massive refactoring of the I-pipe 
implementation and API, aimed at a better integration with Xenomai:
http://git.denx.de/?p=ipipe-2.6.git;a=shortlog;h=refs/heads/core-3.2

It currently supports powerpc, arm, x86 and blackfin, and can be used 
with Xenomai 2.6.1+ and Xenomai 3 systems in dual kernel mode. I will 
roll this patch out officially when Gilles and I are done with fixing 
the rough edges. The plan is to have it shipped with the upcoming 2.6.1.

To sum up: the interrupt pipeline for x86 is maintained, a release for 
3.x kernels is upcoming.

>
> Please, someone could clarify this.
>
> Thanks in advance,
>
> Leo
>
>
>
> [1] http://www.xenomai.org/index.php/Xenomai:Roadmap
>


-- 
Philippe.

Re: [Xenomai-help] Xenomai on kernel 3.x and x86

[Gilles Chanteperdrix]

On 05/14/2012 10:13 AM, Philippe Gerum wrote:
> There is an upcoming patch for linux 3.2, which is the first of the new 
> pipeline "core" series, a massive refactoring of the I-pipe 
> implementation and API, aimed at a better integration with Xenomai:
> http://git.denx.de/?p=ipipe-2.6.git;a=shortlog;h=refs/heads/core-3.2

For those interested, here are a few latency measurements made with this
new patch on the various platforms I have, in order to compare Xenomai
2.6.1 with the current state of the upcoming 3.x branch.

The graphs show clearly that Xenomai 3.x has better average and minimum
latencies on low end platforms. The lower end the platform, the more the
latency graph is shifted to the left.

http://sisyphus.hd.free.fr/~gilles/core-3.2-latencies/

-- 
                                                                Gilles.