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From: Richard Weinberger <richard.weinberger@gmail.com>
Date: Tue, 14 Apr 2020 13:05:56 +0200
Message-ID: <CAFLxGvxDDdhQmkMD0hj1QTEQtxyDpbGeueBG8PY5a2gorUffNg@mail.gmail.com>
Subject: Re: rt_task_unblock() POSIX alternative
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To: Jan Kiszka <jan.kiszka@siemens.com>
Cc: =?UTF-8?Q?Petr_=C4=8Cervenka?= <grugh@centrum.cz>, Xenomai <xenomai@xenomai.org>

On Tue, Apr 14, 2020 at 1:02 PM Jan Kiszka <jan.kiszka@siemens.com> wrote:
>
> On 14.04.20 12:56, Richard Weinberger wrote:
> > On Tue, Apr 14, 2020 at 12:44 PM Jan Kiszka <jan.kiszka@siemens.com> wrote:
> >
> >>> While we are here, is there a guarantee that rt_task_unblock() can unblock
> >>> a thread in every situation?
> >>> I have a large Xenomai 2 application on my desk which seems to assumes that.
> >>
> >> IIRC, it does so for the native/alchemy API.
> >>
> >>>
> >>> As far as I understand it, unblocking tasks is best effort.
> >>> /me has pthread_mutex_lock() in mind which must not return -EINTR as
> >>> required by POSIX.
> >>>
> >>
> >> Well, when mixing APIs, you can end up in such conflicting goals, indeed.
> >
> > I fear more about Xenomai internals which are now based on POSIX APIs.
> > IIRC we talked regarding this issue some time ago.
> >
> > Found the mail:
> > https://www.xenomai.org/pipermail/xenomai/2019-July/041221.html
>
> Indeed, there is a todo...

No big deal. I actually try hard to get rid of all rt_task_unblock()
users in our code base. :-)

-- 
Thanks,
//richard