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Use xchg() instead to prevent double accounting of "nr_busy_cpus" if the status update on the local CPU races with a correction from a remote CPU. No functional changes intended. Reviewed-by: Gautham R. Shenoy Signed-off-by: K Prateek Nayak --- kernel/sched/fair.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index af9f2c1e93f8..0e68371365a5 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -12455,7 +12455,9 @@ static void set_cpu_sd_state_busy(int cpu) if (!sd || !sd->nohz_idle) return; =20 - sd->nohz_idle =3D 0; + if (!xchg(&sd->nohz_idle, 0)) + return; + atomic_inc(&sd->shared->nr_busy_cpus); } =20 @@ -12483,7 +12485,9 @@ static void set_cpu_sd_state_idle(int cpu) if (!sd || sd->nohz_idle) return; =20 - sd->nohz_idle =3D 1; + if (xchg(&sd->nohz_idle, 1)) + return; + atomic_dec(&sd->shared->nr_busy_cpus); } =20 --=20 2.34.1