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From: Michael Schnell <mschnell@lumino.de>
Cc: linux-embedded@vger.kernel.org
Subject: Re: AMP on an SMP system
Date: Fri, 02 Aug 2013 18:00:02 +0200	[thread overview]
Message-ID: <51FBD782.9070309@lumino.de> (raw)
In-Reply-To: <51FBD223.9020809@gmail.com>

On 08/02/2013 05:37 PM, Marco Stornelli wrote:
>
> I don't know your hw so my consideration are really general. 
The hardware is not decided yet (it will be some A9 thingy). So for me 
"really general" is just fine.

> ISRs in rt kernel doesn't exist or at least the only work is to wake 
> up the kernel thread for the management. 
I see.

But how to determine the max latency for this ?

> The thing you can do is to move the kernel thread for interrupt X 
> where you want to manage it, or you can set a specific scheduler 
> policy. For example you can set a SCHED_FIFO with a very high priority 
> for your "really low latency" tasks. RT kernel does the work for you 
> :) You can see here: http://lwn.net/Articles/146861/

This seems be rather easy to do. If this is "good enough" latency wise, 
it seems  to be the way to go.

-Michael

  reply	other threads:[~2013-08-02 16:00 UTC|newest]

Thread overview: 25+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-08-02  8:33 AMP on an SMP system Michael Schnell
2013-08-02 11:42 ` Robert Schwebel
2013-08-02 12:13   ` Michael Schnell
2013-08-02 14:53     ` Marco Stornelli
2013-08-02 15:24       ` Michael Schnell
2013-08-02 15:37         ` Marco Stornelli
2013-08-02 16:00           ` Michael Schnell [this message]
2013-08-02 15:58             ` Marco Stornelli
2013-08-03 19:11       ` Robert Schwebel
2013-08-05  7:25         ` Michael Schnell
2013-08-05  8:17           ` Robert Schwebel
2013-08-05  9:04             ` Michael Schnell
2013-08-04 21:28 ` Lambrecht Jürgen
2013-08-05  7:36   ` Michael Schnell
2013-08-05 10:00   ` Lambrecht Jürgen
2013-08-07  8:23     ` Michael Schnell
2013-08-07  8:29       ` Michael Schnell
2013-08-07  9:04       ` Michael Schnell
2013-08-08  7:41 ` Michael Schnell
  -- strict thread matches above, loose matches on Subject: below --
2013-08-02 16:16 Jon Sevy
2013-08-05  7:45 ` Michael Schnell
2013-08-05  8:21   ` Robert Schwebel
2013-08-05  8:42     ` Michael Schnell
2013-08-05  9:06 Guenter Ebermann
2013-08-05  9:34 ` Michael Schnell

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