Re: CAN State Information

[Wolfgang Grandegger <wg-5Yr1BZd7O62+XT7JhA+gdA@public.gmane.org>]

On 12/09/2011 09:15 AM, Wolfgang Grandegger wrote:
> On 12/09/2011 09:03 AM, kime-Z4QKGCRq86k@public.gmane.org wrote:
>> I plan to spend some time today tracking down the problem.  I am most curious to discover if there is a problem in the msg returned from send_dump_request(). 
>>
>> $ sudo ./canconfig can0 state
>> can0 state: STOPPED
>> $ sudo ./canconfig can1 state
>> can1 state: STOPPED
>> $ "
>> can2: failed to get state 
>> $ sudo ./canconfig can3 state
>> can3: failed to get state 
> 
> OK, what does strace tell you. Is there a system call failing with "-1"?
> Also ftrace could give some hint (assuming that ftrace and function
> tracing is enabled in you kernel):
> 
>   # mount -tdebugfs none /sys/kernel/debug/
>   # cd /sys/kernel/debug/tracing/
>   # echo function > current_tracer
>   # echo "can_*" >  set_ftrace_filter
>   # cat set_ftrace_filter
>   # echo 0 > trace

    # echo 1 > tracing_on

might also be necessary (usually it on by default).

Wolfgang.