sched: move rcu_head to task_group struct
Peter Zijlstra noticed that the rcu_head object need not be present
in every cfs_rq of a group. Move it to the task_group structure
instead.
Signed-off-by: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/kernel/sched.c b/kernel/sched.c
index 235952b..4704807 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -172,6 +172,7 @@
unsigned long shares;
/* spinlock to serialize modification to shares */
spinlock_t lock;
+ struct rcu_head rcu;
};
/* Default task group's sched entity on each cpu */
@@ -258,7 +259,6 @@
*/
struct list_head leaf_cfs_rq_list; /* Better name : task_cfs_rq_list? */
struct task_group *tg; /* group that "owns" this runqueue */
- struct rcu_head rcu;
#endif
};
@@ -7019,8 +7019,8 @@
/* rcu callback to free various structures associated with a task group */
static void free_sched_group(struct rcu_head *rhp)
{
- struct cfs_rq *cfs_rq = container_of(rhp, struct cfs_rq, rcu);
- struct task_group *tg = cfs_rq->tg;
+ struct task_group *tg = container_of(rhp, struct task_group, rcu);
+ struct cfs_rq *cfs_rq;
struct sched_entity *se;
int i;
@@ -7052,7 +7052,7 @@
BUG_ON(!cfs_rq);
/* wait for possible concurrent references to cfs_rqs complete */
- call_rcu(&cfs_rq->rcu, free_sched_group);
+ call_rcu(&tg->rcu, free_sched_group);
}
/* change task's runqueue when it moves between groups.
