Re: [PATCH 1/2] perf sched timehist: Add --show-prio option

[Madadi Vineeth Reddy <vineethr@linux.ibm.com>]

Hi Yang Jihong,

On 06/08/24 07:27, Yang Jihong wrote:
> The --show-prio option is used to display the priority of task.
> It is disabled by default, which is consistent with original behavior.
> 
> The display format is xxx (priority does not change during task running)
> or xxx->yyy (priority changes during task running)
> 

I had done the following steps.
1) Ran 'perf sched record stress-ng --cpu 32 -l 50 --timeout 40s'
2) Changed the nice value of stress-ng while the record was going on.
ps -C stress-ng -o pid=
64195

renice -n 10 -p 64195

3) Then ran 'perf sched timehist --show-prio'

343918.720052 [0015]  stress-ng[64195]    120  0.013      0.013   21.719
.
.
343958.797257 [0009]  stress-ng[64195]    130  40076.812  0.007   0.393

The output shows the final priority change of stress-ng from 120 to 130,
but the transition format xxx->yyy is not displayed.

Am I missing something?

Thanks and Regards
Madadi Vineeth Reddy

> Testcase:
> 
>   # perf sched record nice -n 9 true
>   [ perf record: Woken up 0 times to write data ]
>   [ perf record: Captured and wrote 0.497 MB perf.data ]