[patch 09/15] sched/migration: Move prepare transition to SCHED_STARTING state

Thomas Gleixner
2016-03-10T12:08:06Z

[-- Attachment #1: sched-migration--Move-prepare-transition-to-SCHED_STARTING-state.patch --]
[-- Type: text/plain, Size: 1528 bytes --]

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>
---
kernel/sched/core.c | 20 +++++++++++---------
1 file changed, 11 insertions(+), 9 deletions(-)

--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -5662,11 +5662,6 @@ migration_call(struct notifier_block *nf

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);
@@ -7372,9 +7367,19 @@ int sched_cpu_deactivate(unsigned int cp
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;
}

@@ -7415,11 +7420,8 @@ 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);