[Xenomai] Shared memory between RT and NRT tasks (Posix Skin)

[Xenomai] Shared memory between RT and NRT tasks (Posix Skin)

[Virendra Kate]

Hello,

I am trying to create a shared memory between a RT (Cobalt) and a NRT
(Linux) task. I went through the " A Tour of the Native API " document
which pointed me towards the alchemy (previously "native") API.

Currently we are using the Posix skin as it has better performance. This
link:
http://www.xenomai.org/documentation/xenomai-2.4/html/api/group__posix__shm.html
indicates
that the typical posix share memory API was available for Xenoami Cobalt in
version 2.4.

Since the shared memory section is missing in the Xenomai 3 documentation
and I couldn't find the --wrap shm_open() etc. flags in the
"cobalt.wrappers" file I was wondering if this functionality is supported
in Xenomai 3 Posix skin.

At this point I am avoiding the use of message queues.

Any help is appreciated.

Thanks,
Virendra Kate

Re: [Xenomai] Shared memory between RT and NRT tasks (Posix Skin)

[Greg Gallagher]

Have you considered using xddp sockets instead?  How large is the
memory you are sharing?

-Greg

On Thu, May 3, 2018 at 1:49 PM, Virendra Kate <virendrakate@gmail.com> wrote:
> Hello,
>
> I am trying to create a shared memory between a RT (Cobalt) and a NRT
> (Linux) task. I went through the " A Tour of the Native API " document
> which pointed me towards the alchemy (previously "native") API.
>
> Currently we are using the Posix skin as it has better performance. This
> link:
> http://www.xenomai.org/documentation/xenomai-2.4/html/api/group__posix__shm.html
> indicates
> that the typical posix share memory API was available for Xenoami Cobalt in
> version 2.4.
>
> Since the shared memory section is missing in the Xenomai 3 documentation
> and I couldn't find the --wrap shm_open() etc. flags in the
> "cobalt.wrappers" file I was wondering if this functionality is supported
> in Xenomai 3 Posix skin.
>
> At this point I am avoiding the use of message queues.
>
> Any help is appreciated.
>
> Thanks,
> Virendra Kate
> _______________________________________________
> Xenomai mailing list
> Xenomai@xenomai.org
> https://xenomai.org/mailman/listinfo/xenomai

Re: [Xenomai] Shared memory between RT and NRT tasks (Posix Skin)

[Virendra Kate]

I am still looking into xddp but might not be the best solution for us.

The shared memory is 16MB big.

-Virendra

On Thu, May 3, 2018 at 10:51 AM, Greg Gallagher <greg@embeddedgreg.com> wrote:
> Have you considered using xddp sockets instead?  How large is the
> memory you are sharing?
>
> -Greg
>
> On Thu, May 3, 2018 at 1:49 PM, Virendra Kate <virendrakate@gmail.com> wrote:
>> Hello,
>>
>> I am trying to create a shared memory between a RT (Cobalt) and a NRT
>> (Linux) task. I went through the " A Tour of the Native API " document
>> which pointed me towards the alchemy (previously "native") API.
>>
>> Currently we are using the Posix skin as it has better performance. This
>> link:
>> http://www.xenomai.org/documentation/xenomai-2.4/html/api/group__posix__shm.html
>> indicates
>> that the typical posix share memory API was available for Xenoami Cobalt in
>> version 2.4.
>>
>> Since the shared memory section is missing in the Xenomai 3 documentation
>> and I couldn't find the --wrap shm_open() etc. flags in the
>> "cobalt.wrappers" file I was wondering if this functionality is supported
>> in Xenomai 3 Posix skin.
>>
>> At this point I am avoiding the use of message queues.
>>
>> Any help is appreciated.
>>
>> Thanks,
>> Virendra Kate
>> _______________________________________________
>> Xenomai mailing list
>> Xenomai@xenomai.org
>> https://xenomai.org/mailman/listinfo/xenomai

Re: [Xenomai] Shared memory between RT and NRT tasks (Posix Skin)

[Greg Gallagher]

I can continue to do some digging, but I've only really used xddp.
I'm sure someone on the list can help out.

On Thu, May 3, 2018 at 2:33 PM, Virendra Kate <virendrakate@gmail.com> wrote:
> I am still looking into xddp but might not be the best solution for us.
>
> The shared memory is 16MB big.
>
> -Virendra
>
> On Thu, May 3, 2018 at 10:51 AM, Greg Gallagher <greg@embeddedgreg.com> wrote:
>> Have you considered using xddp sockets instead?  How large is the
>> memory you are sharing?
>>
>> -Greg
>>
>> On Thu, May 3, 2018 at 1:49 PM, Virendra Kate <virendrakate@gmail.com> wrote:
>>> Hello,
>>>
>>> I am trying to create a shared memory between a RT (Cobalt) and a NRT
>>> (Linux) task. I went through the " A Tour of the Native API " document
>>> which pointed me towards the alchemy (previously "native") API.
>>>
>>> Currently we are using the Posix skin as it has better performance. This
>>> link:
>>> http://www.xenomai.org/documentation/xenomai-2.4/html/api/group__posix__shm.html
>>> indicates
>>> that the typical posix share memory API was available for Xenoami Cobalt in
>>> version 2.4.
>>>
>>> Since the shared memory section is missing in the Xenomai 3 documentation
>>> and I couldn't find the --wrap shm_open() etc. flags in the
>>> "cobalt.wrappers" file I was wondering if this functionality is supported
>>> in Xenomai 3 Posix skin.
>>>
>>> At this point I am avoiding the use of message queues.
>>>
>>> Any help is appreciated.
>>>
>>> Thanks,
>>> Virendra Kate
>>> _______________________________________________
>>> Xenomai mailing list
>>> Xenomai@xenomai.org
>>> https://xenomai.org/mailman/listinfo/xenomai

Re: [Xenomai] Shared memory between RT and NRT tasks (Posix Skin)

[Virendra Kate]

Thanks Greg.


On Thu, May 3, 2018 at 11:42 AM Greg Gallagher <greg@embeddedgreg.com>
wrote:

> I can continue to do some digging, but I've only really used xddp.
> I'm sure someone on the list can help out.
>
> On Thu, May 3, 2018 at 2:33 PM, Virendra Kate <virendrakate@gmail.com>
> wrote:
> > I am still looking into xddp but might not be the best solution for us.
> >
> > The shared memory is 16MB big.
> >
> > -Virendra
> >
> > On Thu, May 3, 2018 at 10:51 AM, Greg Gallagher <greg@embeddedgreg.com>
> wrote:
> >> Have you considered using xddp sockets instead?  How large is the
> >> memory you are sharing?
> >>
> >> -Greg
> >>
> >> On Thu, May 3, 2018 at 1:49 PM, Virendra Kate <virendrakate@gmail.com>
> wrote:
> >>> Hello,
> >>>
> >>> I am trying to create a shared memory between a RT (Cobalt) and a NRT
> >>> (Linux) task. I went through the " A Tour of the Native API " document
> >>> which pointed me towards the alchemy (previously "native") API.
> >>>
> >>> Currently we are using the Posix skin as it has better performance.
> This
> >>> link:
> >>>
> http://www.xenomai.org/documentation/xenomai-2.4/html/api/group__posix__shm.html
> >>> indicates
> >>> that the typical posix share memory API was available for Xenoami
> Cobalt in
> >>> version 2.4.
> >>>
> >>> Since the shared memory section is missing in the Xenomai 3
> documentation
> >>> and I couldn't find the --wrap shm_open() etc. flags in the
> >>> "cobalt.wrappers" file I was wondering if this functionality is
> supported
> >>> in Xenomai 3 Posix skin.
> >>>
> >>> At this point I am avoiding the use of message queues.
> >>>
> >>> Any help is appreciated.
> >>>
> >>> Thanks,
> >>> Virendra Kate
> >>> _______________________________________________
> >>> Xenomai mailing list
> >>> Xenomai@xenomai.org
> >>> https://xenomai.org/mailman/listinfo/xenomai
>