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From: "Chris Friesen" <cfriesen@nortel•com>
To: Paolo Doz <paolo.doz@gmail•com>
Cc: linuxppc-dev@ozlabs•org
Subject: Re: While(1) in kernel space
Date: Tue, 08 Jul 2008 08:44:37 -0600	[thread overview]
Message-ID: <48737D55.9000905@nortel.com> (raw)
In-Reply-To: <5468b7f30807080055p69571979i9a565653e523c2c0@mail.gmail.com>

Paolo Doz wrote:
> Hi folks,
> I'm developing a custom SPI driver (char device) on a MPC5200b, the 
> microcontroller linked as slave implements a protocol that must follow 
> strict timing constraints. I need to receive and send messages every 
> 6msec.

What are your timing requirements?  How much over/under 6ms can the 
protocol handle?

Kernel threads might work, but then you're at the mercy of the 
scheduler.  You'd probably be better off using a timer or softirq.

If the latency requirements are really strict, your best bet would 
probably be to use the -rt patches for the kernel.  That requires 
building a custom kernel though.

Chris

      parent reply	other threads:[~2008-07-08 14:54 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-07-08  7:55 While(1) in kernel space Paolo Doz
2008-07-08 14:19 ` Grant Likely
2008-07-08 14:45   ` Arnd Bergmann
2008-07-08 14:47     ` Grant Likely
2008-07-08 20:53       ` Paolo Doz
2008-07-08 14:44 ` Chris Friesen [this message]

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