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charset="utf-8" There is no need to complete the entire scx initialization if a scheduler is failing to be attached due to a hotplug event. Exit early to avoid unnecessary work and simplify the attach flow. Signed-off-by: Andrea Righi --- kernel/sched/ext.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/kernel/sched/ext.c b/kernel/sched/ext.c index 9ddf7a145db6b..489462290142a 100644 --- a/kernel/sched/ext.c +++ b/kernel/sched/ext.c @@ -4445,7 +4445,7 @@ static struct scx_sched *scx_alloc_and_add_sched(stru= ct sched_ext_ops *ops) return ERR_PTR(ret); } =20 -static void check_hotplug_seq(struct scx_sched *sch, +static int check_hotplug_seq(struct scx_sched *sch, const struct sched_ext_ops *ops) { unsigned long long global_hotplug_seq; @@ -4462,8 +4462,11 @@ static void check_hotplug_seq(struct scx_sched *sch, SCX_ECODE_ACT_RESTART | SCX_ECODE_RSN_HOTPLUG, "expected hotplug seq %llu did not match actual %llu", ops->hotplug_seq, global_hotplug_seq); + return -EBUSY; } } + + return 0; } =20 static int validate_ops(struct scx_sched *sch, const struct sched_ext_ops = *ops) @@ -4560,7 +4563,11 @@ static int scx_enable(struct sched_ext_ops *ops, str= uct bpf_link *link) if (((void (**)(void))ops)[i]) set_bit(i, sch->has_op); =20 - check_hotplug_seq(sch, ops); + ret =3D check_hotplug_seq(sch, ops); + if (ret) { + cpus_read_unlock(); + goto err_disable; + } scx_idle_update_selcpu_topology(ops); =20 cpus_read_unlock(); --=20 2.51.0