[PATCH 05/12] sched_ext: Factor out scx_alloc_and_add_sched()

Tejun Heo
2025-04-25T21:58:50Z

More will be moved into scx_sched. Factor out the allocation and kobject
addition path into scx_alloc_and_add_sched().

Signed-off-by: Tejun Heo <tj@kernel.org>
---
kernel/sched/ext.c | 58 ++++++++++++++++++++++++++++------------------
1 file changed, 36 insertions(+), 22 deletions(-)

diff --git a/kernel/sched/ext.c b/kernel/sched/ext.c
index e22717c435ff..bd2d45196bec 100644
--- a/kernel/sched/ext.c
+++ b/kernel/sched/ext.c
@@ -5236,6 +5236,39 @@ static struct kthread_worker *scx_create_rt_helper(const char *name)
return helper;
}

+static struct scx_sched *scx_alloc_and_add_sched(struct sched_ext_ops *ops)
+{
+ struct scx_sched *sch;
+ int ret;
+
+ sch = kzalloc(sizeof(*sch), GFP_KERNEL);
+ if (!sch)
+ return ERR_PTR(-ENOMEM);
+
+ sch->exit_info = alloc_exit_info(ops->exit_dump_len);
+ if (!sch->exit_info) {
+ ret = -ENOMEM;
+ goto err_free_sch;
+ }
+
+ atomic_set(&sch->exit_kind, SCX_EXIT_NONE);
+ sch->ops = *ops;
+ ops->priv = sch;
+
+ sch->kobj.kset = scx_kset;
+ ret = kobject_init_and_add(&sch->kobj, &scx_ktype, NULL, "root");
+ if (ret < 0)
+ goto err_free_ei;
+
+ return sch;
+
+err_free_ei:
+ free_exit_info(sch->exit_info);
+err_free_sch:
+ kfree(sch);
+ return ERR_PTR(ret);
+}
+
static void check_hotplug_seq(const struct sched_ext_ops *ops)
{
unsigned long long global_hotplug_seq;
@@ -5348,27 +5381,12 @@ static int scx_enable(struct sched_ext_ops *ops, struct bpf_link *link)
goto err_unlock;
}

- sch = kzalloc(sizeof(*sch), GFP_KERNEL);
- if (!sch) {
- ret = -ENOMEM;
+ sch = scx_alloc_and_add_sched(ops);
+ if (IS_ERR(sch)) {
+ ret = PTR_ERR(sch);
goto err_unlock;
}

- sch->exit_info = alloc_exit_info(ops->exit_dump_len);
- if (!sch->exit_info) {
- ret = -ENOMEM;
- goto err_free;
- }
-
- sch->kobj.kset = scx_kset;
- ret = kobject_init_and_add(&sch->kobj, &scx_ktype, NULL, "root");
- if (ret < 0)
- goto err_free;
-
- atomic_set(&sch->exit_kind, SCX_EXIT_NONE);
- sch->ops = *ops;
- ops->priv = sch;
-
/*
* Transition to ENABLING and clear exit info to arm the disable path.
* Failure triggers full disabling from here on.
@@ -5566,10 +5584,6 @@ static int scx_enable(struct sched_ext_ops *ops, struct bpf_link *link)

return 0;

-err_free:
- if (sch->exit_info)
- free_exit_info(sch->exit_info);
- kfree(sch);
err_unlock:
mutex_unlock(&scx_enable_mutex);
return ret;
--
2.49.0