[PATCH 18/21] x86: apic: uv: Convert to hotplug state machine

[Sebastian Andrzej Siewior]

Install the callbacks via the state machine.

Signed-off-by: Sebastian Andrzej Siewior <bige...@linutronix.de>
---
 arch/x86/kernel/apic/x2apic_uv_x.c | 31 ++++++-------------------------
 1 file changed, 6 insertions(+), 25 deletions(-)

diff --git a/arch/x86/kernel/apic/x2apic_uv_x.c 
b/arch/x86/kernel/apic/x2apic_uv_x.c
index cb0673c1e940..391b7f8b31c8 100644
--- a/arch/x86/kernel/apic/x2apic_uv_x.c
+++ b/arch/x86/kernel/apic/x2apic_uv_x.c
@@ -927,7 +927,7 @@ static void uv_heartbeat(unsigned long ignored)
        mod_timer(timer, jiffies + SCIR_CPU_HB_INTERVAL);
 }
 
-static void uv_heartbeat_enable(int cpu)
+static int uv_heartbeat_enable(unsigned int cpu)
 {
        while (!uv_cpu_scir_info(cpu)->enabled) {
                struct timer_list *timer = &uv_cpu_scir_info(cpu)->timer;
@@ -941,43 +941,24 @@ static void uv_heartbeat_enable(int cpu)
                /* also ensure that boot cpu is enabled */
                cpu = 0;
        }
+       return 0;
 }
 
 #ifdef CONFIG_HOTPLUG_CPU
-static void uv_heartbeat_disable(int cpu)
+static int uv_heartbeat_disable(unsigned int cpu)
 {
        if (uv_cpu_scir_info(cpu)->enabled) {
                uv_cpu_scir_info(cpu)->enabled = 0;
                del_timer(&uv_cpu_scir_info(cpu)->timer);
        }
        uv_set_cpu_scir_bits(cpu, 0xff);
-}
-
-/*
- * cpu hotplug notifier
- */
-static int uv_scir_cpu_notify(struct notifier_block *self, unsigned long 
action,
-                             void *hcpu)
-{
-       long cpu = (long)hcpu;
-
-       switch (action & ~CPU_TASKS_FROZEN) {
-       case CPU_DOWN_FAILED:
-       case CPU_ONLINE:
-               uv_heartbeat_enable(cpu);
-               break;
-       case CPU_DOWN_PREPARE:
-               uv_heartbeat_disable(cpu);
-               break;
-       default:
-               break;
-       }
-       return NOTIFY_OK;
+       return 0;
 }
 
 static __init void uv_scir_register_cpu_notifier(void)
 {
-       hotcpu_notifier(uv_scir_cpu_notify, 0);
+       cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN, "x86/x2apic-uvx:online",
+                                 uv_heartbeat_enable, uv_heartbeat_disable);
 }
 
 #else /* !CONFIG_HOTPLUG_CPU */
-- 
2.9.3