[Xenomai-help] Compatibility of Xenomai-Versions

[Xenomai-help] Compatibility of Xenomai-Versions

[Roderik.Wildenburg]

How compatible are the different Xenomai-Versions ? 

- E.g. can I use a 2.3.2 application (compiled and linked against 2.3.2
Libraries) on an 2.4.x kernel (kernel with a 2.4.x Xenomai) without
recompiling the application ? 

- Can I link a 2.4.x-application (linked and compiled against 2.4.x
libraries) with an xenomai vendor libriary (e.g. some realtime functions
from a vendor) build with an 2.3.x Xenomai version ?

In my understanding I would say yes, as long as the API and the header
files did not change (type or number of parameters, constants).
Is this correct ? If yes, is there an documentation where and when the
API changed in an significant way ?


Best regards
Roderik 

MAN Roland Druckmaschinen AG
Vorsitzender des Aufsichtsrates: Hanno C. Fiedler
Vorstand: Gerd Finkbeiner (Vorsitzender), Dr. Ingo Koch, Dr. Markus Rall, Paul Steidle    
Sitz der Gesellschaft: Offenbach am Main, Registergericht: Amtsgericht Offenbach HRB-Nr. 42592    
USt-Ident-Nr. DE 250200933

Re: [Xenomai-help] Compatibility of Xenomai-Versions

[Gilles Chanteperdrix]

Roderik.Wildenburg@domain.hid wrote:
 > How compatible are the different Xenomai-Versions ? 
 > 
 > - E.g. can I use a 2.3.2 application (compiled and linked against 2.3.2
 > Libraries) on an 2.4.x kernel (kernel with a 2.4.x Xenomai) without
 > recompiling the application ? 

Xenomai has a notion of ABI revision, which has been increased in
2.4.x. So, no, if you update Xenomai kernel-space support, you have to
update Xenomai user-space support. The ABI revision was increased for a
good reason: some system calls implementation changed, so running with
mixed version would cause random errors.

Xenomai libraries are also versioned, so you will get a loader error if
you try to run an old application with a newer library.

 > - Can I link a 2.4.x-application (linked and compiled against 2.4.x
 > libraries) with an xenomai vendor libriary (e.g. some realtime functions
 > from a vendor) build with an 2.3.x Xenomai version ?

It depends on what is in this library. If there is a call to
xeno_bind_skin, you will get the ABI revision error.

 > 
 > In my understanding I would say yes, as long as the API and the header
 > files did not change (type or number of parameters, constants).
 > Is this correct ? If yes, is there an documentation where and when the
 > API changed in an significant way ?

Look for ksrc/skins/*/API.CHANGES. Note that only external API changes
are documented, internal API changes are not documented though they
caused an ABI revision increase.

-- 


					    Gilles Chanteperdrix.

[Xenomai-help] question about patch: adeos-ipipe-2.6.23-bf5xx-1.7-00.patch

[adam - Li Yi]

Hi Philippe,

I tried to apply patch "adeos-ipipe-2.6.23-bf5xx-1.7-00.patch" to
Blackfin uClinux kernel SVN trunk 2007-Nov-27 but failed. The problem is
that the blackfin uclinux kernel is still 2.6.22. I am wondering at
which svn revision the patch is made?

Thanks!

-Yi 

Re: [Xenomai-help] question about patch: adeos-ipipe-2.6.23-bf5xx-1.7-00.patch

[Philippe Gerum]

adam - Li Yi wrote:
> Hi Philippe,
> 
> I tried to apply patch "adeos-ipipe-2.6.23-bf5xx-1.7-00.patch" to
> Blackfin uClinux kernel SVN trunk 2007-Nov-27 but failed. The problem is
> that the blackfin uclinux kernel is still 2.6.22. I am wondering at
> which svn revision the patch is made?

This patch is against v2.6.23 vanilla. GIT commit
bbf25010f1a6b761914430f5fca081ec8c7accd1. I don't track the Blackfin SVN
repo anymore since 2.6.23, but rather the mainline tree.

-- 
Philippe.

Re: [Xenomai-help] question about patch: adeos-ipipe-2.6.23-bf5xx-1.7-00.patch

[adam - Li Yi]

On Wed, 2007-11-28 at 11:03 +0100, Philippe Gerum wrote:
> adam - Li Yi wrote:
> > Hi Philippe,
> > 
> > I tried to apply patch "adeos-ipipe-2.6.23-bf5xx-1.7-00.patch" to
> > Blackfin uClinux kernel SVN trunk 2007-Nov-27 but failed. The problem is
> > that the blackfin uclinux kernel is still 2.6.22. I am wondering at
> > which svn revision the patch is made?
> 
> This patch is against v2.6.23 vanilla. GIT commit
> bbf25010f1a6b761914430f5fca081ec8c7accd1. I don't track the Blackfin SVN
> repo anymore since 2.6.23, but rather the mainline tree.
> 
Ok. I will try to merge the patch with the Blackfin uclinux SVN. 

-Yi

Re: [Xenomai-help] question about patch: adeos-ipipe-2.6.23-bf5xx-1.7-00.patch

[adam - Li Yi]

Hi Philippe,

Now I understand that this patch is against vanilla linux-2.6.23 git
tree. But since the blackfin uclinux linux kernel will be synced to
vanilla tree when the we do the next release, the kernel in blackfin
uclinux svn trunk is still 2.6.22.

Do you think it make sense to make an adeos patch based on blackfin
uclinux linux-kernel SVN trunk, to allow people working on blackfin
uclinux SVN to use adeos/xenomai? (I tried to merge, but it is not
smooth.)

Thanks,
-Yi


On Wed, 2007-11-28 at 12:15 +0800, adam - Li Yi wrote:
> Hi Philippe,
> 
> I tried to apply patch "adeos-ipipe-2.6.23-bf5xx-1.7-00.patch" to
> Blackfin uClinux kernel SVN trunk 2007-Nov-27 but failed. The problem is
> that the blackfin uclinux kernel is still 2.6.22. I am wondering at
> which svn revision the patch is made?
> 
> Thanks!
> 
> -Yi 
> 
> _______________________________________________
> Xenomai-help mailing list
> Xenomai-help@domain.hid
> https://mail.gna.org/listinfo/xenomai-help

Re: [Xenomai-help] Compatibility of Xenomai-Versions

[Roderik.Wildenburg]

Thank you for your explanations!

Sorry for the following stupid questions but till now I wasn´t aware of the ABI revisions.
How do I, as a simple user of xenomai, recognize when the ABI changed ?

Is the following true ?

Xenomai Version : a.b.c

a changed : change of the API => rework your source code
b changed : change of the ABI => recompile your application 
            and libraries, replace your Xenomai libraries
c changed : no change in application,libraries necessary


Best regards
Roderik

> -----Ursprüngliche Nachricht-----
> Von: xenomai-help-bounces@domain.hid
> [mailto:xenomai-help-bounces@domain.hid] Im Auftrag von Gilles 
> Chanteperdrix
> Gesendet: Dienstag, 27. November 2007 22:47
> An: Wildenburg, Roderik RAEK3 MRA
> Cc: xenomai@xenomai.org
> Betreff: Re: [Xenomai-help] Compatibility of Xenomai-Versions
> 
> Roderik.Wildenburg@domain.hid wrote:
>  > How compatible are the different Xenomai-Versions ? 
>  > 
>  > - E.g. can I use a 2.3.2 application (compiled and linked 
> against 2.3.2
>  > Libraries) on an 2.4.x kernel (kernel with a 2.4.x Xenomai) without
>  > recompiling the application ? 
> 
> Xenomai has a notion of ABI revision, which has been increased in
> 2.4.x. So, no, if you update Xenomai kernel-space support, you have to
> update Xenomai user-space support. The ABI revision was 
> increased for a
> good reason: some system calls implementation changed, so running with
> mixed version would cause random errors.
> 
> Xenomai libraries are also versioned, so you will get a 
> loader error if
> you try to run an old application with a newer library.
> 
>  > - Can I link a 2.4.x-application (linked and compiled against 2.4.x
>  > libraries) with an xenomai vendor libriary (e.g. some 
> realtime functions
>  > from a vendor) build with an 2.3.x Xenomai version ?
> 
> It depends on what is in this library. If there is a call to
> xeno_bind_skin, you will get the ABI revision error.
> 
>  > 
>  > In my understanding I would say yes, as long as the API 
> and the header
>  > files did not change (type or number of parameters, constants).
>  > Is this correct ? If yes, is there an documentation where 
> and when the
>  > API changed in an significant way ?
> 
> Look for ksrc/skins/*/API.CHANGES. Note that only external API changes
> are documented, internal API changes are not documented though they
> caused an ABI revision increase.
> 
> -- 
> 
> 
> 					    Gilles Chanteperdrix.
> 
> _______________________________________________
> Xenomai-help mailing list
> Xenomai-help@domain.hid
> https://mail.gna.org/listinfo/xenomai-help
> 

MAN Roland Druckmaschinen AG
Vorsitzender des Aufsichtsrates: Hanno C. Fiedler
Vorstand: Gerd Finkbeiner (Vorsitzender), Dr. Ingo Koch, Dr. Markus Rall, Paul Steidle    
Sitz der Gesellschaft: Offenbach am Main, Registergericht: Amtsgericht Offenbach HRB-Nr. 42592    
USt-Ident-Nr. DE 250200933

Re: [Xenomai-help] Compatibility of Xenomai-Versions

[Gilles Chanteperdrix]

Roderik.Wildenburg@domain.hid wrote:
 > Thank you for your explanations!
 > 
 > Sorry for the following stupid questions but till now I wasn´t aware of the ABI revisions.
 > How do I, as a simple user of xenomai, recognize when the ABI changed ?

Well, when old user-space support no longer works with new kernel-space
support. The bind operation, done at library initialization time,
returns -ENOEXEC.

 > 
 > Is the following true ?
 > 
 > Xenomai Version : a.b.c
 > 
 > a changed : change of the API => rework your source code
 > b changed : change of the ABI => recompile your application 
 >             and libraries, replace your Xenomai libraries
 > c changed : no change in application,libraries necessary

No, there is no obvious relation between Xenomai versions and ABI/API
versions. Normally, Xenomai libraries versions should get incremented
when the ABI changes.

-- 


					    Gilles Chanteperdrix.

Re: [Xenomai-help] Compatibility of Xenomai-Versions

[Philippe Gerum]

Roderik.Wildenburg@domain.hid wrote:
> Thank you for your explanations!
> 
> Sorry for the following stupid questions but till now I wasn´t aware of the ABI revisions.
> How do I, as a simple user of xenomai, recognize when the ABI changed ?
>

Check the shared library versions.

> Is the following true ?
> 
> Xenomai Version : a.b.c
> 
> a changed : change of the API => rework your source code
> b changed : change of the ABI => recompile your application 
>             and libraries, replace your Xenomai libraries
> c changed : no change in application,libraries necessary
> 

No. Some early a.(b+1).c releases may still run executables compiled for
a.b.c, it really depends on the ABI changes, and we try to avoid them
when possible. The rule of thumb is that no ABI change will ever be made
in a stable branch, such as 2.3.x, so you may expect that any userland
application compiled for 2.3.0 would run over 2.3.5 unmodified. However,
we don't provide any guarantee of such kind to kernel space code. This
is why Xenomai strictly decorrelates userland and kernel supports, i.e.
to provide a stable ABI across releases from any given stable version to
userland programs.

-- 
Philippe.