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CPUs with zero non-idle jiffies do not contribute to the weighted result, but are still processed in the current implementation. Skip CPUs with zero non-idle jiffies early to avoid unnecessary per-cpu arithmetic during aggregation. No functional change intended. Signed-off-by: Zhan Xusheng --- kernel/sched/psi.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/kernel/sched/psi.c b/kernel/sched/psi.c index 59fdb7ebbf22..ce2321793a67 100644 --- a/kernel/sched/psi.c +++ b/kernel/sched/psi.c @@ -387,6 +387,13 @@ static void collect_percpu_times(struct psi_group *gro= up, changed_states |=3D cpu_changed_states; =20 nonidle =3D nsecs_to_jiffies(times[PSI_NONIDLE]); + /* + * A CPU with zero non-idle jiffies does not contribute to the + * weighted per-CPU aggregation. There is no need to include it + * in deltas or total accumulation. + */ + if (!nonidle) + continue; nonidle_total +=3D nonidle; =20 for (s =3D 0; s < PSI_NONIDLE; s++) --=20 2.43.0