[tip:smp/hotplug] s390/mm/pfault: Convert to hotplug state machine

tip-bot for Sebastian Andrzej Siewior
2016-09-19T19:59:40Z

Commit-ID: 84c9ceefecb8fe51c4bfa2a5424dd73bc024e41d
Gitweb: http://git.kernel.org/tip/84c9ceefecb8fe51c4bfa2a5424dd73bc024e41d
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
AuthorDate: Tue, 6 Sep 2016 19:04:53 +0200
Committer: Thomas Gleixner <tglx@linutronix.de>
CommitDate: Mon, 19 Sep 2016 21:44:32 +0200

s390/mm/pfault: Convert to hotplug state machine

Install the callbacks via the state machine.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: linux-s390@vger.kernel.org
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: rt@linutronix.de
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Link: http://lkml.kernel.org/r/20160906170457.32393-18-bigeasy@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

---
arch/s390/mm/fault.c | 30 ++++++++++++------------------
include/linux/cpuhotplug.h | 1 +
2 files changed, 13 insertions(+), 18 deletions(-)

diff --git a/arch/s390/mm/fault.c b/arch/s390/mm/fault.c
index a58bca6..cbb73fa 100644
--- a/arch/s390/mm/fault.c
+++ b/arch/s390/mm/fault.c
@@ -740,28 +740,21 @@ out:
put_task_struct(tsk);
}

-static int pfault_cpu_notify(struct notifier_block *self, unsigned long action,
- void *hcpu)
+static int pfault_cpu_dead(unsigned int cpu)
{
struct thread_struct *thread, *next;
struct task_struct *tsk;

- switch (action & ~CPU_TASKS_FROZEN) {
- case CPU_DEAD:
- spin_lock_irq(&pfault_lock);
- list_for_each_entry_safe(thread, next, &pfault_list, list) {
- thread->pfault_wait = 0;
- list_del(&thread->list);
- tsk = container_of(thread, struct task_struct, thread);
- wake_up_process(tsk);
- put_task_struct(tsk);
- }
- spin_unlock_irq(&pfault_lock);
- break;
- default:
- break;
+ spin_lock_irq(&pfault_lock);
+ list_for_each_entry_safe(thread, next, &pfault_list, list) {
+ thread->pfault_wait = 0;
+ list_del(&thread->list);
+ tsk = container_of(thread, struct task_struct, thread);
+ wake_up_process(tsk);
+ put_task_struct(tsk);
}
- return NOTIFY_OK;
+ spin_unlock_irq(&pfault_lock);
+ return 0;
}

static int __init pfault_irq_init(void)
@@ -775,7 +768,8 @@ static int __init pfault_irq_init(void)
if (rc)
goto out_pfault;
irq_subclass_register(IRQ_SUBCLASS_SERVICE_SIGNAL);
- hotcpu_notifier(pfault_cpu_notify, 0);
+ cpuhp_setup_state_nocalls(CPUHP_S390_PFAULT_DEAD, "s390/pfault:dead",
+ NULL, pfault_cpu_dead);
return 0;

out_pfault:
diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h
index 8f8a48b..dea6696 100644
--- a/include/linux/cpuhotplug.h
+++ b/include/linux/cpuhotplug.h
@@ -26,6 +26,7 @@ enum cpuhp_state {
CPUHP_BLOCK_SOFTIRQ_DEAD,
CPUHP_VIRT_SCSI_DEAD,
CPUHP_ACPI_CPUDRV_DEAD,
+ CPUHP_S390_PFAULT_DEAD,
CPUHP_WORKQUEUE_PREP,
CPUHP_POWER_NUMA_PREPARE,
CPUHP_HRTIMERS_PREPARE,