---

yaml
---
r: 323553
b: refs/heads/master
c: 5d18023
h: refs/heads/master
i:
  323551: 0b6670a
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 0d8ee37e2fcb7b77b9c5dee784beca5a215cad4c
+refs/heads/master: 5d18023294abc22984886bd7185344e0c2be0daf

trunk/kernel/sched/core.c

@@ -5304,27 +5304,17 @@ void idle_task_exit(void)
 }
 
 /*
- * While a dead CPU has no uninterruptible tasks queued at this point,
- * it might still have a nonzero ->nr_uninterruptible counter, because
- * for performance reasons the counter is not stricly tracking tasks to
- * their home CPUs. So we just add the counter to another CPU's counter,
- * to keep the global sum constant after CPU-down:
- */
-static void migrate_nr_uninterruptible(struct rq *rq_src)
-{
-	struct rq *rq_dest = cpu_rq(cpumask_any(cpu_active_mask));
-
-	rq_dest->nr_uninterruptible += rq_src->nr_uninterruptible;
-	rq_src->nr_uninterruptible = 0;
-}
-
-/*
- * remove the tasks which were accounted by rq from calc_load_tasks.
+ * Since this CPU is going 'away' for a while, fold any nr_active delta
+ * we might have. Assumes we're called after migrate_tasks() so that the
+ * nr_active count is stable.
+ *
+ * Also see the comment "Global load-average calculations".
  */
-static void calc_global_load_remove(struct rq *rq)
+static void calc_load_migrate(struct rq *rq)
 {
-	atomic_long_sub(rq->calc_load_active, &calc_load_tasks);
-	rq->calc_load_active = 0;
+	long delta = calc_load_fold_active(rq);
+	if (delta)
+		atomic_long_add(delta, &calc_load_tasks);
 }
 
 /*
@@ -5617,9 +5607,18 @@ migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu)
 		migrate_tasks(cpu);
 		BUG_ON(rq->nr_running != 1); /* the migration thread */
 		raw_spin_unlock_irqrestore(&rq->lock, flags);
+		break;
 
-		migrate_nr_uninterruptible(rq);
-		calc_global_load_remove(rq);
+	case CPU_DEAD:
+		{
+			struct rq *dest_rq;
+
+			local_irq_save(flags);
+			dest_rq = cpu_rq(smp_processor_id());
+			raw_spin_lock(&dest_rq->lock);
+			calc_load_migrate(rq);
+			raw_spin_unlock_irqrestore(&dest_rq->lock, flags);
+		}
 		break;
 #endif
 	}