diff options
author | Thomas Gleixner <tglx@linutronix.de> | 2016-03-10 12:54:18 +0100 |
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committer | Thomas Gleixner <tglx@linutronix.de> | 2016-05-06 14:58:25 +0200 |
commit | f2785ddb5367e217365099294b89d6a84668069e (patch) | |
tree | f67909eb9bff395634056023ed7546d15ba499da | |
parent | 7d97669933eb94245ec9b715753753ec5ca8f646 (diff) | |
download | op-kernel-dev-f2785ddb5367e217365099294b89d6a84668069e.zip op-kernel-dev-f2785ddb5367e217365099294b89d6a84668069e.tar.gz |
sched/hotplug: Move migration CPU_DYING to sched_cpu_dying()
Remove the hotplug notifier and make it an explicit state.
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/20160310120025.502222097@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
-rw-r--r-- | include/linux/cpu.h | 2 | ||||
-rw-r--r-- | include/linux/sched.h | 6 | ||||
-rw-r--r-- | kernel/cpu.c | 2 | ||||
-rw-r--r-- | kernel/sched/core.c | 72 |
4 files changed, 29 insertions, 53 deletions
diff --git a/include/linux/cpu.h b/include/linux/cpu.h index b22b000..21597dc 100644 --- a/include/linux/cpu.h +++ b/include/linux/cpu.h @@ -59,9 +59,7 @@ struct notifier_block; * CPU notifier priorities. */ enum { - /* migration should happen before other stuff but after perf */ CPU_PRI_PERF = 20, - CPU_PRI_MIGRATION = 10, /* bring up workqueues before normal notifiers and down after */ CPU_PRI_WORKQUEUE_UP = 5, diff --git a/include/linux/sched.h b/include/linux/sched.h index 1e5f961..47835cf 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -376,6 +376,12 @@ extern int sched_cpu_starting(unsigned int cpu); extern int sched_cpu_activate(unsigned int cpu); extern int sched_cpu_deactivate(unsigned int cpu); +#ifdef CONFIG_HOTPLUG_CPU +extern int sched_cpu_dying(unsigned int cpu); +#else +# define sched_cpu_dying NULL +#endif + extern void sched_show_task(struct task_struct *p); #ifdef CONFIG_LOCKUP_DETECTOR diff --git a/kernel/cpu.c b/kernel/cpu.c index c134a35..d6eeb8c 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -1223,7 +1223,7 @@ static struct cpuhp_step cpuhp_ap_states[] = { [CPUHP_AP_SCHED_STARTING] = { .name = "sched:starting", .startup = sched_cpu_starting, - .teardown = NULL, + .teardown = sched_cpu_dying, }, /* * Low level startup/teardown notifiers. Run with interrupts diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 8d8d903..a9a65ed 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -5411,51 +5411,6 @@ static void set_rq_offline(struct rq *rq) } } -/* - * migration_call - callback that gets triggered when a CPU is added. - * Here we can start up the necessary migration thread for the new CPU. - */ -static int -migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu) -{ - int cpu = (long)hcpu; - unsigned long flags; - struct rq *rq = cpu_rq(cpu); - - switch (action & ~CPU_TASKS_FROZEN) { - -#ifdef CONFIG_HOTPLUG_CPU - case CPU_DYING: - sched_ttwu_pending(); - /* Update our root-domain */ - raw_spin_lock_irqsave(&rq->lock, flags); - if (rq->rd) { - BUG_ON(!cpumask_test_cpu(cpu, rq->rd->span)); - set_rq_offline(rq); - } - migrate_tasks(rq); - BUG_ON(rq->nr_running != 1); /* the migration thread */ - raw_spin_unlock_irqrestore(&rq->lock, flags); - calc_load_migrate(rq); - break; -#endif - } - - update_max_interval(); - - return NOTIFY_OK; -} - -/* - * Register at high priority so that task migration (migrate_all_tasks) - * happens before everything else. This has to be lower priority than - * the notifier in the perf_event subsystem, though. - */ -static struct notifier_block migration_notifier = { - .notifier_call = migration_call, - .priority = CPU_PRI_MIGRATION, -}; - static void set_cpu_rq_start_time(unsigned int cpu) { struct rq *rq = cpu_rq(cpu); @@ -7158,6 +7113,28 @@ int sched_cpu_starting(unsigned int cpu) return 0; } +#ifdef CONFIG_HOTPLUG_CPU +int sched_cpu_dying(unsigned int cpu) +{ + struct rq *rq = cpu_rq(cpu); + unsigned long flags; + + /* Handle pending wakeups and then migrate everything off */ + sched_ttwu_pending(); + raw_spin_lock_irqsave(&rq->lock, flags); + if (rq->rd) { + BUG_ON(!cpumask_test_cpu(cpu, rq->rd->span)); + set_rq_offline(rq); + } + migrate_tasks(rq); + BUG_ON(rq->nr_running != 1); + raw_spin_unlock_irqrestore(&rq->lock, flags); + calc_load_migrate(rq); + update_max_interval(); + return 0; +} +#endif + void __init sched_init_smp(void) { cpumask_var_t non_isolated_cpus; @@ -7194,12 +7171,7 @@ void __init sched_init_smp(void) static int __init migration_init(void) { - void *cpu = (void *)(long)smp_processor_id(); - sched_rq_cpu_starting(smp_processor_id()); - migration_call(&migration_notifier, CPU_ONLINE, cpu); - register_cpu_notifier(&migration_notifier); - return 0; } early_initcall(migration_init); |