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Date: Mon, 11 Mar 2013 13:45:39 -0400
From: Bruce Ashfield <bruce.ashfield@windriver.com>
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To: David Mulder <dmulder@lasx.com>
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Cc: "yocto@yoctoproject.org" <yocto@yoctoproject.org>
Subject: Re: Can I disable RT throttling?
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On 13-03-11 01:38 PM, David Mulder wrote:
>> From: Trevor Woerner [mailto:twoerner@gmail.com]
>> You can call sched_setaffinity() before fork()ing your task, or use
>> taskset on the cmdline.
>
> Will that work on a core that's offline?

Nope. Only with an online core controlled by the Linux scheduler.
If you do end up trying to get AMP working, you need to plumbing
to load the other OS/kernel in a reserved memory location, set the
program counter and start the OS.

But that secondary OS has to know how to behave in a system that
it doesn't control, and you'll need ways to communicate with it
from Linux.

remoteproc/rpmsg can solve some of the issues that I mention, but
it is far from out of the box.

That's why there's more interest in running a single task with
exclusive CPU in userspace. The work and scaffolding required to
get an AMP system up and running is non trivial.

Cheers,

Bruce

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