> On 4 Jun 2026, at 7:47 PM, Arnaldo Carvalho de Melo <[email protected]> wrote:
>
> On Thu, May 21, 2026 at 11:17:58AM -0300, Arnaldo Carvalho de Melo wrote:
>> On Thu, May 21, 2026 at 02:02:53PM +0530, Athira Rajeev wrote:
>>>> On 27 Apr 2026, at 11:26 AM, Namhyung Kim <[email protected]> wrote:
>>>> On Sun, Apr 26, 2026 at 03:09:30PM +0530, Athira Rajeev wrote:
>>>>> In redhat perftool testsuite, observed fail for this test:
>>>>> -- [ FAIL ] -- perf_sched :: test_timehist :: --with-summary (output
>>>>> regexp parsing)
>>>>>
>>>>> This led to analysis of "perf sched timehist" summary options.
>>>>>
>>>>> # perf sched record -a -o ./perf.data -- sleep 0.1
>>>>> This will record using perf sched record
>>>>>
>>>>> perf sched timeliest has two options "-s" and "-S"
>>>>> # perf sched -i ./perf.data timehist -S
>>>>> -S : Captures summary also at the end
>>>>>
>>>>> # perf sched -i ./perf.data timehist -s
>>>>> -s : Captures only summary
>>>>>
>>>>> The test saves -s result which has only summary and compares with
>>>>> summary which comes at the end from -S . Since there is a difference
>>>>> in these two, test fails.
>>>>>
>>>>> Checking the behaviour change in -S and -s results, difference is:
>>>>>
>>>>> rcu_sched[16] 2 4 0.013 0.001
>>>>> 0.003 0.006 33.23 0
>>>>> migration/11[73] 2 1 0.006 0.006
>>>>> 0.006 0.006 0.00 0
>>>>> migration/3[33] 2 1 0.006 0.006
>>>>> 0.006 0.006 0.00 0
>>>>> - :216753[216753] -1 1 0.041
>>>>> 0.041 0.041 0.041 0.00 0
>>>>> + sleep[216753] -1 1 0.041
>>>>> 0.041 0.041 0.041 0.00 0
>>>>> migration/8[58] 2 1 0.005 0.005
>>>>> 0.005 0.005 0.00 0
>>>>> NetworkManager[811] 1 2 0.089 0.028
>>>>> 0.044 0.060 36.06 0
>>>>> migration/13[83] 2 1 0.005 0.005
>>>>> 0.005 0.005 0.00 0
>>>>>
>>>>> Here 216753 is pid for sleep which is a zombie process. This is
>>>>> happening in latest kernel due to an update in "-S" result.
>>>>> In -S, the process name appears in the results "sleep[216753]",
>>>>> where as in the -s, only pid is present in the summary result
>>>>> ":216753[216753]".
>>>>>
>>>>> After commit 39f473f6d0b2 ("perf sched timehist: decode process names
>>>>> of processes in zombie state")
>>>>> for -S option, if process name is using pid, it uses different way to
>>>>> set it. So that we get the process name and not just Pid.
>>>>>
>>>>> This change went in only for timehist_print_sample() function.
>>>>> Add this improvement in generic place so that even -s option (which
>>>>> captures summary) also will have meaningful information.
>>>>>
>>>>> Signed-off-by: Athira Rajeev <[email protected]>
>>>>
>>>> Acked-by: Namhyung Kim <[email protected]>
>>>>
>>>> Thanks,
>>>> Namhyung
>>> Hi,
>>>
>>> Can we please have this pulled in, if the patch looks fine ?
>>
>> Can you please check applying it on top of current perf-tools-next?
>
> So, this seems to be also addressed by:
>
> commit 39f473f6d0b24cf375893f2110b1cc9d8a079a42
> Author: Anubhav Shelat <[email protected]>
> Date: Wed Jul 16 16:39:15 2025 -0400
>
> perf sched timehist: decode process names of processes in zombie state
>
> Previously when running perf trace timehist --state, when recording
> processes in the zombie state the process name would not be decoded
> properly and appears with just the PID:
>
> 1140057.412177 [0006] Mutter Input Th[3139/3104] 0.956
> 0.019 0.041 S
> 1140057.412222 [0012] :1248612[1248612] 0.000
> 0.000 0.332 Z
> 1140057.412275 [0004] <idle> 0.052
> 0.052 0.953 I
> 1140057.412284 [0008] <idle> 0.070
> 0.070 0.932 I
> 1140057.412333 [0004] KMS thread[3126/3104] 0.953
> 0.112 0.058 S
>
> Now some extra processing has been added to decode the process name:
>
> 1140057.412177 [0006] Mutter Input Th[3139/3104] 0.956
> 0.019 0.041 S
> 1140057.412222 [0012] sleep[1248612] 0.000
> 0.000 0.332 Z
> 1140057.412275 [0004] <idle> 0.052
> 0.052 0.953 I
> 1140057.412284 [0008] <idle> 0.070
> 0.070 0.932 I
> 1140057.412333 [0004] KMS thread[3126/3104] 0.953
> 0.112 0.058 S
>
> Signed-off-by: Anubhav Shelat <[email protected]>
> Link: https://lore.kernel.org/r/[email protected]
> Signed-off-by: Namhyung Kim <[email protected]>
>
>
> No? It is not applying to perf-tools-next, a quick look found the patch
> above.
Hi Arnaldo
commit 39f473f6d0b2 ("perf sched timehist: decode process names
of processes in zombie state”)
added change for -S option. The patch I submitted is to add change in process
name for “-s” option as well
I will check applying this on top of current perf-tools-next
Thanks
Athira
>
> - Arnaldo
