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charset="utf-8" In the idle CPU selection logic, attempting cross-node searches adds unnecessary complexity when CONFIG_NUMA is disabled. Since there's no meaningful concept of nodes in this case, simplify the logic by restricting the idle CPU search to the current node only. Fixes: 48849271e6611 ("sched_ext: idle: Per-node idle cpumasks") Signed-off-by: Andrea Righi --- kernel/sched/ext_idle.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/kernel/sched/ext_idle.c b/kernel/sched/ext_idle.c index 66da03cc0b338..8660d9ae40169 100644 --- a/kernel/sched/ext_idle.c +++ b/kernel/sched/ext_idle.c @@ -138,6 +138,7 @@ static s32 pick_idle_cpu_in_node(const struct cpumask *= cpus_allowed, int node, u goto retry; } =20 +#ifdef CONFIG_NUMA /* * Tracks nodes that have not yet been visited when searching for an idle * CPU across all available nodes. @@ -186,6 +187,13 @@ static s32 pick_idle_cpu_from_online_nodes(const struc= t cpumask *cpus_allowed, i =20 return cpu; } +#else +static inline s32 +pick_idle_cpu_from_online_nodes(const struct cpumask *cpus_allowed, int no= de, u64 flags) +{ + return -EBUSY; +} +#endif =20 /* * Find an idle CPU in the system, starting from @node. --=20 2.49.0