Re: [RFC PATCH 2/2] sched/tracing: Add TASK_RTLOCK_WAIT to TASK_REPORT

[Sebastian Andrzej Siewior]

On 2021-11-29 12:36:01 [+0000], Valentin Schneider wrote:
> TASK_RTLOCK_WAIT currently isn't part of TASK_REPORT, thus a task blocking
> on an rtlock will appear as having a task state == 0, IOW TASK_RUNNING.
> 
> The actual state is saved in p->saved_state, but reading it after reading
> p->__state has a few issues:
> o that could still be TASK_RUNNING in the case of e.g. rt_spin_lock
> o ttwu_state_match() might have changed that to TASK_RUNNING
> 
> Add TASK_RTLOCK_WAIT to TASK_REPORT.
> 
> Signed-off-by: Valentin Schneider <valentin.schneider@xxxxxxx>

We used to have the D state which was used in the locked case and was
sufficient. With the rework to TASK_RTLOCK_WAIT (which made other things
easier) we lost that. It makes debuging/ looking into the system more
obvious or does not hide things so why not.

Reviewed-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>

Sebastian