That helps a lot. About the isolation, let me explain. In approaches like ARINC653 (the OS used in the avionics industry) or MILS (which is more in a research stage), each partition gets a fixed amount of time. To clarify, let's assume that a partition is a thread for seL4.
By isolation, I then mean that the scheduler repeats the same static schedule. There is a schedule of all tasks that is repeated every XXX ms (XXX being what we call the major frame). Nothing can preempt this. Such a schedule is done for safety (every task has the time to be executed) and security (nobody can infer any information based on the task execution time). I need to read more the manual of the RT branch. I will do that. Also, any information about how to try/test it? How do you guys test the RT extensions? What emulator are you using for development purposes? Thanks! Julien. On Thu, May 26, 2016 at 1:21 PM, Ihor Kuz UNSW <[email protected]> wrote: > > > On 27 May 2016, at 1:16 am, Julien Delange <[email protected]> > wrote: > > > > 2. In the RT-camkes extensions, I have the following new attributes: > > _period > > _budget > > _priority > > > > > > What is the semantics of these attributes? > > The basic model is that every CAmkES thread (unless specified otherwise) > has a scheduling context (SC). The above attributes set the parameters of > the associated scheduling context. If not explicitly specified then a > thread’s SC has default values (10000) for the period and budget. The > values are in microseconds. > > With regards to the period and budget they match the same attributes in > the scheduling contexts as provided by the kernel. See the kernel manual > (RT version) for more details. Priority is the same as in previous > versions of seL4. > > > Any information about them? How they are supposed to be isolated from > each other then? > > I’m not sure what you mean by isolated. Can you elaborate? > > > How to define the scheduling plan for the system then? Also, how these > attributes apply to all thread: a thread is created for each interface of > the component, so, how can we then define the priority/budget of each > thread? Do these attributes apply to all the components of the thread? > > You set these attributes per thread. The threads are either the control > thread (<component>._period, etc) or a thread per interface > (<component>.<interface name>_period, etc.) > > Hope this helps a bit. > > Ihor. > > -- > Dr. Ihor Kuz > Senior Research Engineer | Trustworthy Systems | DATA61 | CSIRO > Conjoint Senior Lecturer | CSE | UNSW > E [email protected] T + 61 2 8306 0582 > Locked Bag 6016, UNSW, Sydney NSW 1466, Australia > www.data61.csiro.au > > CSIRO’s Digital Productivity business unit and NICTA have joined forces to > create digital powerhouse Data61 > > > ________________________________ > > The information in this e-mail may be confidential and subject to legal > professional privilege and/or copyright. National ICT Australia Limited > accepts no liability for any damage caused by this email or its attachments. >
_______________________________________________ Devel mailing list [email protected] https://sel4.systems/lists/listinfo/devel
