[tip: sched/core] sched/fair: Also gate overloaded status update for SD_ASYM_CPUCAPACITY

[tip-bot2 for Ricardo Neri]

The following commit has been merged into the sched/core branch of tip:

Commit-ID:     6060d61d13a10da8c90da4eadf4a421825149883
Gitweb:        https://git.kernel.org/tip/6060d61d13a10da8c90da4eadf4a421825149883
Author:        Ricardo Neri <ricardo.neri-calderon@xxxxxxxxxxxxxxx>
AuthorDate:    Mon, 20 Jul 2026 19:43:18 -07:00
Committer:     Peter Zijlstra <peterz@xxxxxxxxxxxxx>
CommitterDate: Fri, 07 Aug 2026 18:27:10 +02:00

sched/fair: Also gate overloaded status update for SD_ASYM_CPUCAPACITY

The argument sg_overloaded of update_sg_lb_stats() is only consumed when
balancing at the root domain. It only makes sense to update it in such a
case. Commit 3229adbe7875 ("sched/fair: Do not compute overloaded status
unnecessarily during lb") updated the logic accordingly but missed the case
in which the root domain has the SD_ASYM_CPUCAPACITY flag. Fix this.

Fixes: 3229adbe7875 ("sched/fair: Do not compute overloaded status unnecessarily during lb")
Reported-by: Chen Yu <yu.c.chen@xxxxxxxxx>
Signed-off-by: Ricardo Neri <ricardo.neri-calderon@xxxxxxxxxxxxxxx>
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Reviewed-by: Vincent Guittot <vincent.guittot@xxxxxxxxxx>
Tested-by: Christian Loehle <christian.loehle@xxxxxxx>
Tested-by: Andrea Righi <arighi@xxxxxxxxxx>
Link: https://patch.msgid.link/20260720-rneri-fix-cas-clusters-v6-2-bb500bf4afd4@xxxxxxxxxxxxxxx
---
 kernel/sched/fair.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 974e091..2c5cfec 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -11973,7 +11973,9 @@ static inline void update_sg_lb_stats(struct lb_env *env,
 			/* Check for a misfit task on the cpu */
 			if (sgs->group_misfit_task_load < rq->misfit_task_load) {
 				sgs->group_misfit_task_load = rq->misfit_task_load;
-				*sg_overloaded = 1;
+
+				if (balancing_at_rd)
+					*sg_overloaded = 1;
 			}
 		} else if (env->idle && sched_reduced_capacity(rq, env->sd)) {
 			/* Check for a task running on a CPU with reduced capacity */