[Crash-utility] FW: patch for slight modification to runq -g command

[Dave Anderson]

Qiao, Daisuke and Zhang,

Can you guys comment on this patch?  It looks reasonable enough.

Thanks,
  Dave

----- Original Message -----
> 
> 
> 
> 
> 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
> 
> 
> 
> 
> 
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