sched: Move up affinity check to mitigate useless redoing overhead

[platform/adaptation/renesas_rcar/renesas_kernel.git] / kernel / sched / fair.c

diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index dfa92b7..b8ef321 100644 (file)
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -3896,10 +3896,14 @@ int can_migrate_task(struct task_struct *p, struct lb_env *env)
        int tsk_cache_hot = 0;
        /*
         * We do not migrate tasks that are:
-        * 1) running (obviously), or
+        * 1) throttled_lb_pair, or
         * 2) cannot be migrated to this CPU due to cpus_allowed, or
-        * 3) are cache-hot on their current CPU.
+        * 3) running (obviously), or
+        * 4) are cache-hot on their current CPU.
         */
+       if (throttled_lb_pair(task_group(p), env->src_cpu, env->dst_cpu))
+               return 0;
+
        if (!cpumask_test_cpu(env->dst_cpu, tsk_cpus_allowed(p))) {
                int new_dst_cpu;
 
@@ -3967,9 +3971,6 @@ static int move_one_task(struct lb_env *env)
        struct task_struct *p, *n;
 
        list_for_each_entry_safe(p, n, &env->src_rq->cfs_tasks, se.group_node) {
-               if (throttled_lb_pair(task_group(p), env->src_rq->cpu, env->dst_cpu))
-                       continue;
-
                if (!can_migrate_task(p, env))
                        continue;
 
@@ -4021,7 +4022,7 @@ static int move_tasks(struct lb_env *env)
                        break;
                }
 
-               if (throttled_lb_pair(task_group(p), env->src_cpu, env->dst_cpu))
+               if (!can_migrate_task(p, env))
                        goto next;
 
                load = task_h_load(p);
@@ -4032,9 +4033,6 @@ static int move_tasks(struct lb_env *env)
                if ((load / 2) > env->imbalance)
                        goto next;
 
-               if (!can_migrate_task(p, env))
-                       goto next;
-
                move_task(p, env);
                pulled++;
                env->imbalance -= load;