[RFC PATCH v4 17/19] sched/fair: wrapper for cfs_rq->min_vruntime

[Vineeth Remanan Pillai <vpillai@digitalocean.com>]

From: Aaron Lu <aaron.lu@linux.alibaba.com>

Add a wrapper function cfs_rq_min_vruntime(cfs_rq) to
return cfs_rq->min_vruntime.

It will be used in the following patch, no functionality
change.

Signed-off-by: Aaron Lu <ziqian.lzq@antfin.com>
---
 kernel/sched/fair.c | 27 ++++++++++++++++-----------
 1 file changed, 16 insertions(+), 11 deletions(-)

diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 840d27628d36..ab32b22b0574 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -450,6 +450,11 @@ find_matching_se(struct sched_entity **se, struct sched_entity **pse)
 
 #endif	/* CONFIG_FAIR_GROUP_SCHED */
 
+static inline u64 cfs_rq_min_vruntime(struct cfs_rq *cfs_rq)
+{
+	return cfs_rq->min_vruntime;
+}
+
 static __always_inline
 void account_cfs_rq_runtime(struct cfs_rq *cfs_rq, u64 delta_exec);
 
@@ -486,7 +491,7 @@ static void update_min_vruntime(struct cfs_rq *cfs_rq)
 	struct sched_entity *curr = cfs_rq->curr;
 	struct rb_node *leftmost = rb_first_cached(&cfs_rq->tasks_timeline);
 
-	u64 vruntime = cfs_rq->min_vruntime;
+	u64 vruntime = cfs_rq_min_vruntime(cfs_rq);
 
 	if (curr) {
 		if (curr->on_rq)
@@ -506,7 +511,7 @@ static void update_min_vruntime(struct cfs_rq *cfs_rq)
 	}
 
 	/* ensure we never gain time by being placed backwards. */
-	cfs_rq->min_vruntime = max_vruntime(cfs_rq->min_vruntime, vruntime);
+	cfs_rq->min_vruntime = max_vruntime(cfs_rq_min_vruntime(cfs_rq), vruntime);
 #ifndef CONFIG_64BIT
 	smp_wmb();
 	cfs_rq->min_vruntime_copy = cfs_rq->min_vruntime;
@@ -3816,7 +3821,7 @@ static inline void update_misfit_status(struct task_struct *p, struct rq *rq) {}
 static void check_spread(struct cfs_rq *cfs_rq, struct sched_entity *se)
 {
 #ifdef CONFIG_SCHED_DEBUG
-	s64 d = se->vruntime - cfs_rq->min_vruntime;
+	s64 d = se->vruntime - cfs_rq_min_vruntime(cfs_rq);
 
 	if (d < 0)
 		d = -d;
@@ -3829,7 +3834,7 @@ static void check_spread(struct cfs_rq *cfs_rq, struct sched_entity *se)
 static void
 place_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int initial)
 {
-	u64 vruntime = cfs_rq->min_vruntime;
+	u64 vruntime = cfs_rq_min_vruntime(cfs_rq);
 
 	/*
 	 * The 'current' period is already promised to the current tasks,
@@ -3922,7 +3927,7 @@ enqueue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int flags)
 	 * update_curr().
 	 */
 	if (renorm && curr)
-		se->vruntime += cfs_rq->min_vruntime;
+		se->vruntime += cfs_rq_min_vruntime(cfs_rq);
 
 	update_curr(cfs_rq);
 
@@ -3933,7 +3938,7 @@ enqueue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int flags)
 	 * fairness detriment of existing tasks.
 	 */
 	if (renorm && !curr)
-		se->vruntime += cfs_rq->min_vruntime;
+		se->vruntime += cfs_rq_min_vruntime(cfs_rq);
 
 	/*
 	 * When enqueuing a sched_entity, we must:
@@ -4046,7 +4051,7 @@ dequeue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int flags)
 	 * can move min_vruntime forward still more.
 	 */
 	if (!(flags & DEQUEUE_SLEEP))
-		se->vruntime -= cfs_rq->min_vruntime;
+		se->vruntime -= cfs_rq_min_vruntime(cfs_rq);
 
 	/* return excess runtime on last dequeue */
 	return_cfs_rq_runtime(cfs_rq);
@@ -6542,7 +6547,7 @@ static void migrate_task_rq_fair(struct task_struct *p, int new_cpu)
 			min_vruntime = cfs_rq->min_vruntime;
 		} while (min_vruntime != min_vruntime_copy);
 #else
-		min_vruntime = cfs_rq->min_vruntime;
+		min_vruntime = cfs_rq_min_vruntime(cfs_rq);
 #endif
 
 		se->vruntime -= min_vruntime;
@@ -10007,7 +10012,7 @@ static void task_fork_fair(struct task_struct *p)
 		resched_curr(rq);
 	}
 
-	se->vruntime -= cfs_rq->min_vruntime;
+	se->vruntime -= cfs_rq_min_vruntime(cfs_rq);
 	rq_unlock(rq, &rf);
 }
 
@@ -10127,7 +10132,7 @@ static void detach_task_cfs_rq(struct task_struct *p)
 		 * cause 'unlimited' sleep bonus.
 		 */
 		place_entity(cfs_rq, se, 0);
-		se->vruntime -= cfs_rq->min_vruntime;
+		se->vruntime -= cfs_rq_min_vruntime(cfs_rq);
 	}
 
 	detach_entity_cfs_rq(se);
@@ -10141,7 +10146,7 @@ static void attach_task_cfs_rq(struct task_struct *p)
 	attach_entity_cfs_rq(se);
 
 	if (!vruntime_normalized(p))
-		se->vruntime += cfs_rq->min_vruntime;
+		se->vruntime += cfs_rq_min_vruntime(cfs_rq);
 }
 
 static void switched_from_fair(struct rq *rq, struct task_struct *p)
-- 
2.17.1