[PATCH 14/60] kvm: Make kvm_running_vcpus point to struct kvm_vcpu_common

[Jörg Rödel]

From: Joerg Roedel <joerg.roedel@xxxxxxx>

This will remove the need to update kvm_running_vcpu on plane
switches.

Signed-off-by: Joerg Roedel <joerg.roedel@xxxxxxx>
---
 arch/arm64/kvm/arch_timer.c     |  3 ++-
 arch/arm64/kvm/vgic/vgic-init.c |  3 ++-
 include/linux/kvm_host.h        |  2 +-
 virt/kvm/kvm_main.c             | 18 +++++++++++-------
 4 files changed, 16 insertions(+), 10 deletions(-)

diff --git a/arch/arm64/kvm/arch_timer.c b/arch/arm64/kvm/arch_timer.c
index cbea4d9ee955..b2c4f422414e 100644
--- a/arch/arm64/kvm/arch_timer.c
+++ b/arch/arm64/kvm/arch_timer.c
@@ -204,7 +204,8 @@ static void soft_timer_cancel(struct hrtimer *hrt)
 
 static irqreturn_t kvm_arch_timer_handler(int irq, void *dev_id)
 {
-	struct kvm_vcpu *vcpu = *(struct kvm_vcpu **)dev_id;
+	struct kvm_vcpu_common *common = *(struct kvm_vcpu_common **)dev_id;
+	struct kvm_vcpu *vcpu = common->current_vcpu;
 	struct arch_timer_context *ctx;
 	struct timer_map map;
 
diff --git a/arch/arm64/kvm/vgic/vgic-init.c b/arch/arm64/kvm/vgic/vgic-init.c
index 933983bb2005..a12b89b423d5 100644
--- a/arch/arm64/kvm/vgic/vgic-init.c
+++ b/arch/arm64/kvm/vgic/vgic-init.c
@@ -730,7 +730,8 @@ void kvm_vgic_cpu_down(void)
 
 static irqreturn_t vgic_maintenance_handler(int irq, void *data)
 {
-	struct kvm_vcpu *vcpu = *(struct kvm_vcpu **)data;
+	struct kvm_vcpu_common *common = *(struct kvm_vcpu_common **)data;
+	struct kvm_vcpu *vcpu = common->current_vcpu;
 
 	/*
 	 * We cannot rely on the vgic maintenance interrupt to be
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index b334c15d834e..d54f299218a4 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -2462,7 +2462,7 @@ static inline bool kvm_is_visible_memslot(struct kvm_memory_slot *memslot)
 }
 
 struct kvm_vcpu *kvm_get_running_vcpu(void);
-struct kvm_vcpu * __percpu *kvm_get_running_vcpus(void);
+struct kvm_vcpu_common * __percpu *kvm_get_running_vcpus(void);
 
 #if IS_ENABLED(CONFIG_HAVE_KVM_IRQ_BYPASS)
 struct kvm_kernel_irqfd;
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 2c16e124a507..9c07321e30f4 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -113,7 +113,7 @@ LIST_HEAD(vm_list);
 static struct kmem_cache *kvm_vcpu_cache;
 
 static __read_mostly struct preempt_ops kvm_preempt_ops;
-static DEFINE_PER_CPU(struct kvm_vcpu *, kvm_running_vcpu);
+static DEFINE_PER_CPU(struct kvm_vcpu_common *, kvm_running_vcpu);
 
 static struct dentry *kvm_debugfs_dir;
 
@@ -165,7 +165,7 @@ void vcpu_load(struct kvm_vcpu *vcpu)
 {
 	int cpu = get_cpu();
 
-	__this_cpu_write(kvm_running_vcpu, vcpu);
+	__this_cpu_write(kvm_running_vcpu, vcpu->common);
 	preempt_notifier_register(&vcpu->preempt_notifier);
 	kvm_arch_vcpu_load(vcpu, cpu);
 	put_cpu();
@@ -3954,7 +3954,7 @@ void __kvm_vcpu_kick(struct kvm_vcpu *vcpu, bool wait)
 	 * kick" check does not need atomic operations if kvm_vcpu_kick is used
 	 * within the vCPU thread itself.
 	 */
-	if (vcpu == __this_cpu_read(kvm_running_vcpu)) {
+	if (vcpu == kvm_get_running_vcpu()) {
 		if (vcpu->mode == IN_GUEST_MODE)
 			WRITE_ONCE(vcpu->mode, EXITING_GUEST_MODE);
 		goto out;
@@ -6500,7 +6500,7 @@ static void kvm_sched_in(struct preempt_notifier *pn, int cpu)
 	WRITE_ONCE(vcpu->preempted, false);
 	WRITE_ONCE(vcpu->ready, false);
 
-	__this_cpu_write(kvm_running_vcpu, vcpu);
+	__this_cpu_write(kvm_running_vcpu, vcpu->common);
 	kvm_arch_vcpu_load(vcpu, cpu);
 
 	WRITE_ONCE(vcpu->scheduled_out, false);
@@ -6532,12 +6532,16 @@ static void kvm_sched_out(struct preempt_notifier *pn,
  */
 struct kvm_vcpu *kvm_get_running_vcpu(void)
 {
-	struct kvm_vcpu *vcpu;
+	struct kvm_vcpu_common *common;
+	struct kvm_vcpu *vcpu = NULL;
 
 	preempt_disable();
-	vcpu = __this_cpu_read(kvm_running_vcpu);
+	common = __this_cpu_read(kvm_running_vcpu);
 	preempt_enable();
 
+	if (common)
+		vcpu = common->current_vcpu;
+
 	return vcpu;
 }
 EXPORT_SYMBOL_FOR_KVM_INTERNAL(kvm_get_running_vcpu);
@@ -6545,7 +6549,7 @@ EXPORT_SYMBOL_FOR_KVM_INTERNAL(kvm_get_running_vcpu);
 /**
  * kvm_get_running_vcpus - get the per-CPU array of currently running vcpus.
  */
-struct kvm_vcpu * __percpu *kvm_get_running_vcpus(void)
+struct kvm_vcpu_common * __percpu *kvm_get_running_vcpus(void)
 {
         return &kvm_running_vcpu;
 }
-- 
2.53.0