Re: [Socketcan-users] Message stalls in SocketCan Layer?

["Michael Jäntsch" <michael.jaentsch@in.tum.de>]

Hi,

sorry for the late reply. I wanted to test the older kernel and
therefore needed to setup the OS from scratch which I didn't have time
to do right away. Now, I tested it with Ubuntu 11.04 and kernel 2.6.38-13.
The problem appears a lot less often. From the time frame of a few
minutes we went to something more like half an hour. So maybe this has
been there all along but did not appear frequently enough to be noticed.
For the reasons I already mentioned I'm still pretty sure this has
nothing to do with our code.
Does anybody have an idea how to go about debugging this?

On 03.02.2012 20:41, Wolfgang Grandegger wrote:
> On 02/03/2012 05:57 PM, Oliver Hartkopp wrote:
>> please consider that if it works on other machines with the same kernel that
>> there could be some changes within the USB subsystem or some interrupt or
>> ACPI/powersaving issues too.
>>
>> Going back to an older Kernel is a good check - don't know, if you also can go
>> further (3.1, 3.2) with Ubuntu 11.10 too ?!?
>>
>> Maybe there's some USB debugging available to check whether the URB has been
>> sent properly to the USB wire and if the interrupt of the USB controller
>> reached the system after sending.
> IIUC, he said that the time stamps indicated that the USB transfers have
> happened in time. The delays occured later. That's wired, indeed.
Wolfgang is right, the debug output of the driver indicated that the USB
transfers happened in time which is why I the guys from PEAK send me to
you. This looks to me like the messages get stalled somewhere in the
PF_CAN netlayer, but I'm also not a hundred percent sure how to verify
this, as this of course not that reproducable. Any ideas?

thanks
Michael

-- 
Technische Universität München
Michael Jäntsch
Fakultät für Informatik
Robotics and Embedded Systems
Parkring 13
85748 Garching bei München
Tel: + 49.89.289.17626
Fax: + 49.89.289.17637
michael.jaentsch@in.tum.de
www6.in.tum.de