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Date: Fri, 1 Mar 2019 07:07:26 -0800 (PST)
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Subject: Re: Why couldn't an operating system be written in ada
From: fabien.chouteau@gmail.com
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Xref: reader01.eternal-september.org comp.lang.ada:55744
Date: 2019-03-01T07:07:26-08:00
List-Id: <comp.lang.ada>

I implemented the SMP support in Ravenscar. You are right in you analysis.

On Wednesday, February 27, 2019 at 11:12:18 PM UTC+1, Niklas Holsti wrote:
> The implementation of protected objects may have to be somewhat 
> different. In a single-core system, mutual exclusion can be implemented 
> by the "ceiling priority" method, but that doesn't work in multi-core 
> systems, so more conventional locks must likely be used.
> 

We use "fair locks" to keep a constant worst case access to the protected object.