Merge branch 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull smp hotplug updates from Thomas Gleixner:
 "This is the next part of the hotplug rework.

   - Convert all notifiers with a priority assigned

   - Convert all CPU_STARTING/DYING notifiers

     The final removal of the STARTING/DYING infrastructure will happen
     when the merge window closes.

  Another 700 hundred line of unpenetrable maze gone :)"

* 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (70 commits)
  timers/core: Correct callback order during CPU hot plug
  leds/trigger/cpu: Move from CPU_STARTING to ONLINE level
  powerpc/numa: Convert to hotplug state machine
  arm/perf: Fix hotplug state machine conversion
  irqchip/armada: Avoid unused function warnings
  ARC/time: Convert to hotplug state machine
  clocksource/atlas7: Convert to hotplug state machine
  clocksource/armada-370-xp: Convert to hotplug state machine
  clocksource/exynos_mct: Convert to hotplug state machine
  clocksource/arm_global_timer: Convert to hotplug state machine
  rcu: Convert rcutree to hotplug state machine
  KVM/arm/arm64/vgic-new: Convert to hotplug state machine
  smp/cfd: Convert core to hotplug state machine
  x86/x2apic: Convert to CPU hotplug state machine
  profile: Convert to hotplug state machine
  timers/core: Convert to hotplug state machine
  hrtimer: Convert to hotplug state machine
  x86/tboot: Convert to hotplug state machine
  arm64/armv8 deprecated: Convert to hotplug state machine
  hwtracing/coresight-etm4x: Convert to hotplug state machine
  ...

1 files changed, 8 insertions, 24 deletions

diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index ce3d8e5be73e..2e791367c576 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -3155,12 +3155,13 @@ static void hardware_enable_nolock(void *junk)
 	}
 }
 
-static void hardware_enable(void)
+static int kvm_starting_cpu(unsigned int cpu)
 {
 	raw_spin_lock(&kvm_count_lock);
 	if (kvm_usage_count)
 		hardware_enable_nolock(NULL);
 	raw_spin_unlock(&kvm_count_lock);
+	return 0;
 }
 
 static void hardware_disable_nolock(void *junk)
@@ -3173,12 +3174,13 @@ static void hardware_disable_nolock(void *junk)
 	kvm_arch_hardware_disable();
 }
 
-static void hardware_disable(void)
+static int kvm_dying_cpu(unsigned int cpu)
 {
 	raw_spin_lock(&kvm_count_lock);
 	if (kvm_usage_count)
 		hardware_disable_nolock(NULL);
 	raw_spin_unlock(&kvm_count_lock);
+	return 0;
 }
 
 static void hardware_disable_all_nolock(void)
@@ -3219,21 +3221,6 @@ static int hardware_enable_all(void)
 	return r;
 }
 
-static int kvm_cpu_hotplug(struct notifier_block *notifier, unsigned long val,
-			   void *v)
-{
-	val &= ~CPU_TASKS_FROZEN;
-	switch (val) {
-	case CPU_DYING:
-		hardware_disable();
-		break;
-	case CPU_STARTING:
-		hardware_enable();
-		break;
-	}
-	return NOTIFY_OK;
-}
-
 static int kvm_reboot(struct notifier_block *notifier, unsigned long val,
 		      void *v)
 {
@@ -3500,10 +3487,6 @@ int kvm_io_bus_unregister_dev(struct kvm *kvm, enum kvm_bus bus_idx,
 	return r;
 }
 
-static struct notifier_block kvm_cpu_notifier = {
-	.notifier_call = kvm_cpu_hotplug,
-};
-
 static int kvm_debugfs_open(struct inode *inode, struct file *file,
 			   int (*get)(void *, u64 *), int (*set)(void *, u64),
 			   const char *fmt)
@@ -3754,7 +3737,8 @@ int kvm_init(void *opaque, unsigned vcpu_size, unsigned vcpu_align,
 			goto out_free_1;
 	}
 
-	r = register_cpu_notifier(&kvm_cpu_notifier);
+	r = cpuhp_setup_state_nocalls(CPUHP_AP_KVM_STARTING, "AP_KVM_STARTING",
+				      kvm_starting_cpu, kvm_dying_cpu);
 	if (r)
 		goto out_free_2;
 	register_reboot_notifier(&kvm_reboot_notifier);
@@ -3808,7 +3792,7 @@ out_free:
 	kmem_cache_destroy(kvm_vcpu_cache);
 out_free_3:
 	unregister_reboot_notifier(&kvm_reboot_notifier);
-	unregister_cpu_notifier(&kvm_cpu_notifier);
+	cpuhp_remove_state_nocalls(CPUHP_AP_KVM_STARTING);
 out_free_2:
 out_free_1:
 	kvm_arch_hardware_unsetup();
@@ -3831,7 +3815,7 @@ void kvm_exit(void)
 	kvm_async_pf_deinit();
 	unregister_syscore_ops(&kvm_syscore_ops);
 	unregister_reboot_notifier(&kvm_reboot_notifier);
-	unregister_cpu_notifier(&kvm_cpu_notifier);
+	cpuhp_remove_state_nocalls(CPUHP_AP_KVM_STARTING);
 	on_each_cpu(hardware_disable_nolock, NULL, 1);
 	kvm_arch_hardware_unsetup();
 	kvm_arch_exit();