sched/fair: Remove duplicate load_per_task computations

Since we already compute (but don't store) the sgs load_per_task value
in update_sg_lb_stats() we might as well store it and not re-compute
it later on.

Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/n/tip-ym1vmljiwbzgdnnrwp9azftq@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

kernel/sched/fair.c

@@ -4476,7 +4476,6 @@ static inline void update_sg_lb_stats(struct lb_env *env,
 {
 	unsigned long nr_running, max_nr_running, min_nr_running;
 	unsigned long load, max_cpu_load, min_cpu_load;
-	unsigned long avg_load_per_task = 0;
 	int i;
 
 	/* Tally up the load of all CPUs in the group */
@@ -4531,9 +4530,9 @@ static inline void update_sg_lb_stats(struct lb_env *env,
 	 *      the hierarchy?
 	 */
 	if (sgs->sum_nr_running)
-		avg_load_per_task = sgs->sum_weighted_load / sgs->sum_nr_running;
+		sgs->load_per_task = sgs->sum_weighted_load / sgs->sum_nr_running;
 
-	if ((max_cpu_load - min_cpu_load) >= avg_load_per_task &&
+	if ((max_cpu_load - min_cpu_load) >= sgs->load_per_task &&
 	    (max_nr_running - min_nr_running) > 1)
 		sgs->group_imb = 1;
 
@@ -4776,15 +4775,7 @@ static inline void calculate_imbalance(struct lb_env *env, struct sd_lb_stats *s
 	struct sg_lb_stats *local, *busiest;
 
 	local = &sds->local_stat;
-	if (local->sum_nr_running) {
-		local->load_per_task =
-			local->sum_weighted_load / local->sum_nr_running;
-	}
-
 	busiest = &sds->busiest_stat;
-	/* busiest must have some tasks */
-	busiest->load_per_task =
-		busiest->sum_weighted_load / busiest->sum_nr_running;
 
 	if (busiest->group_imb) {
 		busiest->load_per_task =