sched/migration: Move prepare transition to SCHED_STARTING state

We can piggy pack that on the SCHED_STARTING state. It's not required before
the cpu actually comes online. Name the function proper as it has nothing to
do with migration.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160310120025.248226511@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

1 files changed, 11 insertions, 9 deletions

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 0a3107809972..bafc308e6d45 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -5424,11 +5424,6 @@ migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu)
 
         switch (action & ~CPU_TASKS_FROZEN) {
 
-        case CPU_UP_PREPARE:
-                rq->calc_load_update = calc_load_update;
-                account_reset_rq(rq);
-                break;
-
         case CPU_ONLINE:
                 /* Update our root-domain */
                 raw_spin_lock_irqsave(&rq->lock, flags);
@@ -7139,9 +7134,19 @@ int sched_cpu_deactivate(unsigned int cpu)
         return 0;
 }
 
+static void sched_rq_cpu_starting(unsigned int cpu)
+{
+        struct rq *rq = cpu_rq(cpu);
+
+        rq->calc_load_update = calc_load_update;
+        account_reset_rq(rq);
+        update_max_interval();
+}
+
 int sched_cpu_starting(unsigned int cpu)
 {
         set_cpu_rq_start_time(cpu);
+        sched_rq_cpu_starting(cpu);
         return 0;
 }
 
@@ -7182,11 +7187,8 @@ void __init sched_init_smp(void)
 static int __init migration_init(void)
 {
         void *cpu = (void *)(long)smp_processor_id();
-        int err;
 
-        /* Initialize migration for the boot CPU */
-        err = migration_call(&migration_notifier, CPU_UP_PREPARE, cpu);
-        BUG_ON(err == NOTIFY_BAD);
+        sched_rq_cpu_starting(smp_processor_id());
         migration_call(&migration_notifier, CPU_ONLINE, cpu);
         register_cpu_notifier(&migration_notifier);