Hi,
We're debugging an in-house application that makes use of hard limit extensively. We
ran into a lot of timing windows (all our own making) and we use runq -g command a lot.
The current runq -g display only the RBROOT pointer. It really is a bit inconvenient to
traverse the task_group hierarchy. It would be nice to have the command also display the
corresponding task_group, cfs_rq pointer (at a minimum). Since the way we crash the system
by messing up the nr_running and h_nr_running, so we also display those two fields at the
same time. Here's an example of before and after.
CPU 4
CURRENT: PID: 0 TASK: ffff8840668c0380 COMMAND: "swapper"
TASK_GROUP RT_RQ: ffff8800027d3820
RT PRIO_ARRAY: ffff8800027d3820
[no tasks queued]
TASK_GROUP CFS_RQ: ffff8800027d36e0
CFS RB_ROOT: ffff8800027d3710
GROUP CFS RB_ROOT: ffff883ff69bcc30 <TDAT>
GROUP CFS RB_ROOT: ffff884006290e30 <User>
GROUP CFS RB_ROOT: ffff88400641c430 <TDWMVP1>
GROUP CFS RB_ROOT: ffff88400646b030 <ServDown1:0>
GROUP CFS RB_ROOT: ffff884006492630 <ServOrder1:1>
GROUP CFS RB_ROOT: ffff883ff058fe30 <TDWMWD57> (THROTTLED)
GROUP CFS RB_ROOT: ffff88047889ee30 <S:WD:3d:35fa>
[120] PID: 27655 TASK: ffff8805078ce2c0 COMMAND:
"actmain"
<<< more throttled groups removed >>>
CPU 4
CURRENT: PID: 0 CFS: ffff8800027d36e0 TASK: ffff8840668c0380 COMMAND:
"swapper"
TASK_GROUP RT_RQ: ffff8800027d3820
RT PRIO_ARRAY: ffff8800027d3820
[no tasks queued]
TASK_GROUP CFS_RQ: ffff8800027d36e0
CFS RB_ROOT: ffff8800027d3710
GROUP: ffff88405394d000 CFS: ffff883ff69bcc00 RB_ROOT: ffff883ff69bcc30 <TDAT>
(0 0)
GROUP: ffff88405906c400 CFS: ffff884006290e00 RB_ROOT: ffff884006290e30
<User> (0 0)
GROUP: ffff884055081000 CFS: ffff88400641c400 RB_ROOT: ffff88400641c430
<TDWMVP1> (0 0)
GROUP: ffff884055081c00 CFS: ffff88400646b000 RB_ROOT: ffff88400646b030
<ServDown1:0> (0 0)
GROUP: ffff8840580fd400 CFS: ffff884006492600 RB_ROOT: ffff884006492630
<ServOrder1:1> (0 0)
GROUP: ffff884058f58c00 CFS: ffff883ff058fe00 RB_ROOT:
ffff883ff058fe30 <TDWMWD57> (7 9) (THROTTLED)
GROUP: ffff8808fb976000 CFS: ffff88047889ee00 RB_ROOT:
ffff88047889ee30 <S:WD:3d:35fa> (1 1)
[120] PID: 27655 TASK: ffff8805078ce2c0 COMMAND:
"actmain"
<<< more throttled groups removed >>>
I have attached the patch we use to display additional information. Could you please take
a look at my proposal to see if it is possible that you include this kind of display
format.
Thanks,
Anthony