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From: Marc Kleine-Budde <mkl@pengutronix.de>
To: Wolfgang Grandegger <wg@grandegger.com>
Cc: Henrik Bork Steffensen <hbs@rosetechnology.dk>,
	linux-can@vger.kernel.org
Subject: Re: at91_can.c: Data transmission stops
Date: Mon, 26 Nov 2012 17:36:42 +0100	[thread overview]
Message-ID: <50B39A9A.3020709@pengutronix.de> (raw)
In-Reply-To: <50B389D6.4050308@grandegger.com>

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On 11/26/2012 04:25 PM, Wolfgang Grandegger wrote:
>> I am considering protecting tx objects as Wolfgang suggests in the
>> pch_can thread.
> 
> This problem is with SMP in the first place. Can you show your .config.
> The c_can driver uses similar code than the at91_can and they have
> therefore the same issues if the kernel is preemptable, IIUC. Should not
> be a big deal to adapt the following patch:

From my point of view, it should be possible to implement that algorithm
lock-free, as there is only one writer and one reader of the two
variables. I'll have a look at it tomorrow.

Marc

-- 
Pengutronix e.K.                  | Marc Kleine-Budde           |
Industrial Linux Solutions        | Phone: +49-231-2826-924     |
Vertretung West/Dortmund          | Fax:   +49-5121-206917-5555 |
Amtsgericht Hildesheim, HRA 2686  | http://www.pengutronix.de   |


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      parent reply	other threads:[~2012-11-26 16:36 UTC|newest]

Thread overview: 17+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-11-26 14:28 at91_can.c: Data transmission stops Henrik Bork Steffensen
2012-11-26 15:25 ` Wolfgang Grandegger
2012-11-26 16:29   ` Henrik Bork Steffensen
2012-11-27 14:11     ` Henrik Bork Steffensen
2012-11-27 16:31       ` Wolfgang Grandegger
2012-11-28 14:22         ` Henrik Bork Steffensen
2012-11-28 14:29           ` Marc Kleine-Budde
2012-11-28 15:09             ` Henrik Bork Steffensen
2012-11-28 15:12               ` Marc Kleine-Budde
2012-11-28 15:44                 ` Henrik Bork Steffensen
2012-11-28 16:23                   ` Wolfgang Grandegger
2012-12-03 16:13                     ` Henrik Bork Steffensen
2012-11-28 14:38           ` Wolfgang Grandegger
2012-11-28 15:17             ` Henrik Bork Steffensen
2012-11-28 14:56         ` Marc Kleine-Budde
2012-11-28 15:17           ` Wolfgang Grandegger
2012-11-26 16:36   ` Marc Kleine-Budde [this message]

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