[LITMUS^RT] How to stop all the rt-tasks manually

[Glenn Elliott]

On Feb 9, 2014, at 8:57 AM, Sanjib Das <cnt.sanjib at googlemail.com> wrote:

> Hello Björn,
> 
> No i haven't tried with killall.
> what will be parameter for the killall command,
> killall -g rtspin doesnt work
> also
> killall -g rcu_preempt
> 
> how should I try it ?
> 
> Thanks in advance
> 
> Sanjib
> On 09.02.2014 13:54, Björn Brandenburg wrote:
>> On 09 Feb 2014, at 05:11, Sanjib Das <cnt.sanjib at googlemail.com> wrote:
>> 
>>> Dear Concern,
>>> 
>>> I am wondering if there is any way to kill all the running real-time task manually.
>> Have you tried killall?
>> 
>> - Björn
>> 
>> 
>>> I am trying to run G-EDF and C-EDF with different tasks and because of wrong parameter I found "rcu_preempt detected stalls on cpus/tasks", as a result my rt tasks were still running.
>>> 
>>> "
>>> [ 2072.588370] Could not switch plugin: -16
>>> [ 2107.177026] Could not switch plugin: -16
>>> [ 2120.735386] Could not switch plugin: -16
>>> [ 2131.718955] Could not switch plugin: -16
>>> [ 2173.427350] INFO: rcu_preempt detected stalls on CPUs/tasks: {} (detected by 1, t=600017 jiffies, g=53906, c=53905, q=0)
>>> [ 2173.427371] INFO: Stall ended before state dump start
>>> [ 2189.814720] Could not switch plugin: -16
>>> [ 2353.473222] INFO: rcu_preempt detected stalls on CPUs/tasks: {} (detected by 1, t=780022 jiffies, g=53906, c=53905, q=0)
>>> [ 2353.473241] INFO: Stall ended before state dump start
>>> [ 2533.519115] INFO: rcu_preempt detected stalls on CPUs/tasks: {} (detected by 1, t=960027 jiffies, g=53906, c=53905, q=0)
>>> [ 2533.519131] INFO: Stall ended before state dump start
>>> 
>>> "
>>> 
>>> 
>>> Though I ran the command using sudo,
>>> "
>>> Error: Cannot write to /proc/litmus/active_plugin. Do you have root privileges?
>>> Error: Setting new plugin failed.
>>> Are there any active real-time tasks?
>>> sdas at sdas-lab:~/littest/liblitmus$
>>> "
>>> 
>>> Any suggestions will be very helpful.
>>> 
>>> Thanks in advance


“sudo pkill -9 rtspin” should work, unless the tasks are stuck in an uninterruptible state.  If that pkill command won’t work, then I think you have no choice but to reboot or even a hard reset.  You shouldn’t kill rcu_preempt—it’s a kernel demon.

-Glenn