[patch V2 04/67] irqchip/gicv3: Convert to hotplug state machine

[Anna-Maria Gleixner]

From: Richard Cochran <rcochran@xxxxxxxxxxxxx>

Install the callbacks via the state machine.

Signed-off-by: Richard Cochran <rcochran@xxxxxxxxxxxxx>
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>
Cc: Jason Cooper <jason@xxxxxxxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Marc Zyngier <marc.zyngier@xxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Signed-off-by: Anna-Maria Gleixner <anna-maria@xxxxxxxxxxxxx>
---
 drivers/irqchip/irq-gic-v3.c | 22 +++++++---------------
 include/linux/cpuhotplug.h   |  1 +
 2 files changed, 8 insertions(+), 15 deletions(-)

diff --git a/drivers/irqchip/irq-gic-v3.c b/drivers/irqchip/irq-gic-v3.c
index 2c5ba0e..6fc56c3 100644
--- a/drivers/irqchip/irq-gic-v3.c
+++ b/drivers/irqchip/irq-gic-v3.c
@@ -538,23 +538,13 @@ static void gic_cpu_init(void)
 }
 
 #ifdef CONFIG_SMP
-static int gic_secondary_init(struct notifier_block *nfb,
-			      unsigned long action, void *hcpu)
+
+static int gic_starting_cpu(unsigned int cpu)
 {
-	if (action == CPU_STARTING || action == CPU_STARTING_FROZEN)
-		gic_cpu_init();
-	return NOTIFY_OK;
+	gic_cpu_init();
+	return 0;
 }
 
-/*
- * Notifier for enabling the GIC CPU interface. Set an arbitrarily high
- * priority because the GIC needs to be up before the ARM generic timers.
- */
-static struct notifier_block gic_cpu_notifier = {
-	.notifier_call = gic_secondary_init,
-	.priority = 100,
-};
-
 static u16 gic_compute_target_list(int *base_cpu, const struct cpumask *mask,
 				   unsigned long cluster_id)
 {
@@ -634,7 +624,9 @@ static void gic_raise_softirq(const struct cpumask *mask, unsigned int irq)
 static void gic_smp_init(void)
 {
 	set_smp_cross_call(gic_raise_softirq);
-	register_cpu_notifier(&gic_cpu_notifier);
+	cpuhp_setup_state_nocalls(CPUHP_AP_IRQ_GICV3_STARTING,
+				  "AP_IRQ_GICV3_STARTING", gic_starting_cpu,
+				  NULL);
 }
 
 static int gic_set_affinity(struct irq_data *d, const struct cpumask *mask_val,
diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h
index edc8adf..d6e4a06 100644
--- a/include/linux/cpuhotplug.h
+++ b/include/linux/cpuhotplug.h
@@ -10,6 +10,7 @@ enum cpuhp_state {
 	CPUHP_AP_OFFLINE,
 	CPUHP_AP_SCHED_STARTING,
 	CPUHP_AP_IRQ_GIC_STARTING,
+	CPUHP_AP_IRQ_GICV3_STARTING,
 	CPUHP_AP_NOTIFY_STARTING,
 	CPUHP_AP_ONLINE,
 	CPUHP_TEARDOWN_CPU,
-- 
2.8.1