sched/fair: Remove unused cfs_rq.idle_nr_running

cfs_rq.idle_nr_running field is not used anywhere so we can remove the
useless associated computation. Last user went in commit 5e963f2
("sched/fair: Commit to EEVDF").

Signed-off-by: Vincent Guittot <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Reviewed-by: Dietmar Eggemann <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

Author: vingu-linaro

kernel/sched/debug.c

@@ -846,8 +846,6 @@ void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
 	SEQ_printf(m, "  .%-30s: %d\n", "nr_running", cfs_rq->nr_running);
 	SEQ_printf(m, "  .%-30s: %d\n", "h_nr_runnable", cfs_rq->h_nr_runnable);
 	SEQ_printf(m, "  .%-30s: %d\n", "h_nr_queued", cfs_rq->h_nr_queued);
-	SEQ_printf(m, "  .%-30s: %d\n", "idle_nr_running",
-			cfs_rq->idle_nr_running);
 	SEQ_printf(m, "  .%-30s: %d\n", "h_nr_idle", cfs_rq->h_nr_idle);
 	SEQ_printf(m, "  .%-30s: %ld\n", "load", cfs_rq->load.weight);
 #ifdef CONFIG_SMP

kernel/sched/fair.c

@@ -3674,8 +3674,6 @@ account_entity_enqueue(struct cfs_rq *cfs_rq, struct sched_entity *se)
 	}
 #endif
 	cfs_rq->nr_running++;
-	if (se_is_idle(se))
-		cfs_rq->idle_nr_running++;
 }
 
 static void
@@ -3689,8 +3687,6 @@ account_entity_dequeue(struct cfs_rq *cfs_rq, struct sched_entity *se)
 	}
 #endif
 	cfs_rq->nr_running--;
-	if (se_is_idle(se))
-		cfs_rq->idle_nr_running--;
 }
 
 /*
@@ -13507,7 +13503,7 @@ int sched_group_set_idle(struct task_group *tg, long idle)
 	for_each_possible_cpu(i) {
 		struct rq *rq = cpu_rq(i);
 		struct sched_entity *se = tg->se[i];
-		struct cfs_rq *parent_cfs_rq, *grp_cfs_rq = tg->cfs_rq[i];
+		struct cfs_rq *grp_cfs_rq = tg->cfs_rq[i];
 		bool was_idle = cfs_rq_is_idle(grp_cfs_rq);
 		long idle_task_delta;
 		struct rq_flags rf;
@@ -13518,14 +13514,6 @@ int sched_group_set_idle(struct task_group *tg, long idle)
 		if (WARN_ON_ONCE(was_idle == cfs_rq_is_idle(grp_cfs_rq)))
 			goto next_cpu;
 
-		if (se->on_rq) {
-			parent_cfs_rq = cfs_rq_of(se);
-			if (cfs_rq_is_idle(grp_cfs_rq))
-				parent_cfs_rq->idle_nr_running++;
-			else
-				parent_cfs_rq->idle_nr_running--;
-		}
-
 		idle_task_delta = grp_cfs_rq->h_nr_queued -
 				  grp_cfs_rq->h_nr_idle;
 		if (!cfs_rq_is_idle(grp_cfs_rq))

kernel/sched/sched.h

@@ -648,7 +648,6 @@ struct cfs_rq {
 	unsigned int		nr_running;
 	unsigned int		h_nr_queued;       /* SCHED_{NORMAL,BATCH,IDLE} */
 	unsigned int		h_nr_runnable;     /* SCHED_{NORMAL,BATCH,IDLE} */
-	unsigned int		idle_nr_running;   /* SCHED_IDLE */
 	unsigned int		h_nr_idle; /* SCHED_IDLE */
 
 	s64			avg_vruntime;