[PATCH 1/5] sched: Expose css_tg()

Tejun Heo
2024-08-26T22:58:28Z

A new BPF extensible sched_class will use css_tg() in the init and exit
paths to visit all task_groups by walking cgroups.

v4: __setscheduler_prio() is already exposed. Dropped from this patch.

v3: Dropped SCHED_CHANGE_BLOCK() as upstream is adding more generic cleanup
mechanism.

v2: Expose SCHED_CHANGE_BLOCK() too and update the description.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: David Vernet <dvernet@meta.com>
Acked-by: Josh Don <joshdon@google.com>
Acked-by: Hao Luo <haoluo@google.com>
Acked-by: Barret Rhoden <brho@google.com>
---
kernel/sched/core.c | 5 -----
kernel/sched/sched.h | 5 +++++
2 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index b0cec06bb1fa..a59ac9b11e3b 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -8957,11 +8957,6 @@ void sched_move_task(struct task_struct *tsk)
}
}

-static inline struct task_group *css_tg(struct cgroup_subsys_state *css)
-{
- return css ? container_of(css, struct task_group, css) : NULL;
-}
-
static struct cgroup_subsys_state *
cpu_cgroup_css_alloc(struct cgroup_subsys_state *parent_css)
{
diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index 2416b3866256..07333c545ddc 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -515,6 +515,11 @@ static inline int walk_tg_tree(tg_visitor down, tg_visitor up, void *data)
return walk_tg_tree_from(&root_task_group, down, up, data);
}

+static inline struct task_group *css_tg(struct cgroup_subsys_state *css)
+{
+ return css ? container_of(css, struct task_group, css) : NULL;
+}
+
extern int tg_nop(struct task_group *tg, void *data);

#ifdef CONFIG_FAIR_GROUP_SCHED
--
2.46.0