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From: Niklas Holsti <niklas.holsti@tidorum.invalid>
Newsgroups: comp.lang.ada
Subject: Re: STM32F4 Discovery, communication and libraries
Date: Fri, 29 Aug 2014 18:59:49 +0300
Organization: Tidorum Ltd
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Date: 2014-08-29T18:59:49+03:00
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On 14-08-29 10:34 , Dmitry A. Kazakov wrote:

> Ravenscar tasking profile has serious constraints preventing this. The
> nature of the constraints is to statically ensure schedulability.

That's what they (= the people whoe defined the profile) often say, but
it is not quite true. Even within Ravenscar constraints, one can build
very dynamic task interactions, which is nice for implementing stuff in
a Ravenscar system, but which makes schedulability analysis difficult.

To ensure simple schedulability analysis, Ravenscar must be supplemented
with further strong design rules, for example limiting each task to have
a single point of suspension, on a single protected object. _Those_
rules can become really nasty from the designer's point of view.

-- 
Niklas Holsti
Tidorum Ltd
niklas holsti tidorum fi
      .      @       .