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. - Arnaldo
