[PATCH 11/31] sched: Add @reason to sched_move_task()

[Tejun Heo <tj@xxxxxxxxxx>]

sched_move_task() can be called for both cgroup and autogroup moves. Add a
parameter to distinguish the two cases. This will be used by a new
sched_class to track cgroup migrations.

Signed-off-by: Tejun Heo <tj@xxxxxxxxxx>
Reviewed-by: David Vernet <dvernet@xxxxxxxx>
Acked-by: Josh Don <joshdon@xxxxxxxxxx>
Acked-by: Hao Luo <haoluo@xxxxxxxxxx>
Acked-by: Barret Rhoden <brho@xxxxxxxxxx>
---
 kernel/sched/autogroup.c | 4 ++--
 kernel/sched/core.c      | 4 ++--
 kernel/sched/sched.h     | 7 ++++++-
 3 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/kernel/sched/autogroup.c b/kernel/sched/autogroup.c
index 991fc9002535..2be1b10ce93e 100644
--- a/kernel/sched/autogroup.c
+++ b/kernel/sched/autogroup.c
@@ -151,7 +151,7 @@ void sched_autogroup_exit_task(struct task_struct *p)
 	 * see this thread after that: we can no longer use signal->autogroup.
 	 * See the PF_EXITING check in task_wants_autogroup().
 	 */
-	sched_move_task(p);
+	sched_move_task(p, SCHED_MOVE_TASK_AUTOGROUP);
 }
 
 static void
@@ -183,7 +183,7 @@ autogroup_move_group(struct task_struct *p, struct autogroup *ag)
 	 * sched_autogroup_exit_task().
 	 */
 	for_each_thread(p, t)
-		sched_move_task(t);
+		sched_move_task(t, SCHED_MOVE_TASK_AUTOGROUP);
 
 	unlock_task_sighand(p, &flags);
 	autogroup_kref_put(prev);
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 0699b49b1a21..9c5bfeeb30ba 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -10210,7 +10210,7 @@ static void sched_change_group(struct task_struct *tsk)
  * now. This function just updates tsk->se.cfs_rq and tsk->se.parent to reflect
  * its new group.
  */
-void sched_move_task(struct task_struct *tsk)
+void sched_move_task(struct task_struct *tsk, enum sched_move_task_reason reason)
 {
 	int queued, running, queue_flags =
 		DEQUEUE_SAVE | DEQUEUE_MOVE | DEQUEUE_NOCLOCK;
@@ -10321,7 +10321,7 @@ static void cpu_cgroup_attach(struct cgroup_taskset *tset)
 	struct cgroup_subsys_state *css;
 
 	cgroup_taskset_for_each(task, css, tset)
-		sched_move_task(task);
+		sched_move_task(task, SCHED_MOVE_TASK_CGROUP);
 }
 
 #ifdef CONFIG_UCLAMP_TASK_GROUP
diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index 3c6ea8296ae4..ef8da88e677c 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -506,7 +506,12 @@ extern void sched_online_group(struct task_group *tg,
 extern void sched_destroy_group(struct task_group *tg);
 extern void sched_release_group(struct task_group *tg);
 
-extern void sched_move_task(struct task_struct *tsk);
+enum sched_move_task_reason {
+	SCHED_MOVE_TASK_CGROUP,
+	SCHED_MOVE_TASK_AUTOGROUP,
+};
+extern void sched_move_task(struct task_struct *tsk,
+			    enum sched_move_task_reason reason);
 
 #ifdef CONFIG_FAIR_GROUP_SCHED
 extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
-- 
2.38.1