[RFC 07/60] sched: Reduce dependencies of init_tg_cfs_entry()

[Jan H . Schönherr]

Decouple init_tg_cfs_entry() from other structures' implementation
details, so that it only updates/accesses task group related fields
of the CFS runqueue and its SE.

This prepares calling this function in slightly different contexts.

Signed-off-by: Jan H. Schönherr <jscho...@amazon.de>
---
 kernel/sched/core.c  |  3 ++-
 kernel/sched/fair.c  | 13 +++++--------
 kernel/sched/sched.h |  4 ++--
 3 files changed, 9 insertions(+), 11 deletions(-)

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index c38a54f57e90..48e37c3baed1 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -6019,7 +6019,8 @@ void __init sched_init(void)
                 * directly in rq->cfs (i.e root_task_group->se[] = NULL).
                 */
                init_cfs_bandwidth(&root_task_group.cfs_bandwidth);
-               init_tg_cfs_entry(&root_task_group, &rq->cfs, NULL, i, NULL);
+               root_task_group.cfs_rq[i] = &rq->cfs;
+               init_tg_cfs_entry(&root_task_group, &rq->cfs, NULL, rq, NULL);
 #endif /* CONFIG_FAIR_GROUP_SCHED */
 
                rq->rt.rt_runtime = def_rt_bandwidth.rt_runtime;
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 3de0158729a6..c0dd5825556c 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -9843,8 +9843,9 @@ int alloc_fair_sched_group(struct task_group *tg, struct 
task_group *parent)
                if (!se)
                        goto err_free_rq;
 
+               tg->cfs_rq[i] = cfs_rq;
                init_cfs_rq(cfs_rq);
-               init_tg_cfs_entry(tg, cfs_rq, se, i, parent->cfs_rq[i]);
+               init_tg_cfs_entry(tg, cfs_rq, se, cpu_rq(i), parent->cfs_rq[i]);
                init_entity_runnable_average(se);
        }
 
@@ -9900,17 +9901,13 @@ void unregister_fair_sched_group(struct task_group *tg)
 }
 
 void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq,
-                       struct sched_entity *se, int cpu,
-                       struct cfs_rq *parent)
+                      struct sched_entity *se, struct rq *rq,
+                      struct cfs_rq *parent)
 {
-       struct rq *rq = cpu_rq(cpu);
-
        cfs_rq->tg = tg;
        cfs_rq->rq = rq;
-       init_cfs_rq_runtime(cfs_rq);
-
-       tg->cfs_rq[cpu] = cfs_rq;
        cfs_rq->my_se = se;
+       init_cfs_rq_runtime(cfs_rq);
 
        /* se could be NULL for root_task_group */
        if (!se)
diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index 926a26d816a2..b8c8dfd0e88d 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -427,8 +427,8 @@ extern int alloc_fair_sched_group(struct task_group *tg, 
struct task_group *pare
 extern void online_fair_sched_group(struct task_group *tg);
 extern void unregister_fair_sched_group(struct task_group *tg);
 extern void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq,
-                       struct sched_entity *se, int cpu,
-                       struct cfs_rq *parent);
+                             struct sched_entity *se, struct rq *rq,
+                             struct cfs_rq *parent);
 extern void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b);
 
 extern void __refill_cfs_bandwidth_runtime(struct cfs_bandwidth *cfs_b);
-- 
2.9.3.1.gcba166c.dirty