Re: Private or public task ?

["Hibou57 (Yannick Duchêne)" <yannick_duchene@yahoo.fr>]

On 9 fév, 16:20, Robert A Duff <bobd...@shell01.TheWorld.com> wrote:
> You should read all the stuff in the Real Time annex about priorities
> and ceilings and policies and whatnot.
>
> No, protected procedures and functions are not potentially blocking.
The misunderstanding was because I was misled on the meaning of
"blocking".
Jean-Pierre's words changed the situation (see his post).

> In your multiprocessor example, task#1 cannot procede
> into the protected procedure until task#2 lets go
> of it, but that's not blocking.  No lower-or-equal priority
> task can preempt task#1.  One possible implementation is
> that task#1 spins on the lock, which is OK because you
> made sure your protected procedure executes in a short
> bounded time.
I've later learned today about spin, but I still have to learn more
about it (that's an other area).

> Protected entries, on the other hand, are potentially blocking,
> because they put the task to sleep for an arbitrarily long time
> (until the barrier becomes True).
Unbounded