KVM: Move vcpu alloc and init invocation to common code

Now that all architectures tightly couple vcpu allocation/free with the
mandatory calls to kvm_{un}init_vcpu(), move the sequences verbatim to
common KVM code.

Move both allocation and initialization in a single patch to eliminate
thrash in arch specific code.  The bisection benefits of moving the two
pieces in separate patches is marginal at best, whereas the odds of
introducing a transient arch specific bug are non-zero.

Acked-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

2 files changed, 20 insertions, 30 deletions

diff --git a/virt/kvm/arm/arm.c b/virt/kvm/arm/arm.c
index 0d8fb6973414..a7d661fc5683 100644
--- a/virt/kvm/arm/arm.c
+++ b/virt/kvm/arm/arm.c
@@ -290,32 +290,9 @@ int kvm_arch_vcpu_precreate(struct kvm *kvm, unsigned int id)
 	return 0;
 }
 
-struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm, unsigned int id)
+int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
 {
-	int err;
-	struct kvm_vcpu *vcpu;
-
-	vcpu = kmem_cache_zalloc(kvm_vcpu_cache, GFP_KERNEL);
-	if (!vcpu) {
-		err = -ENOMEM;
-		goto out;
-	}
-
-	err = kvm_vcpu_init(vcpu, kvm, id);
-	if (err)
-		goto free_vcpu;
-
-	err = create_hyp_mappings(vcpu, vcpu + 1, PAGE_HYP);
-	if (err)
-		goto vcpu_uninit;
-
-	return vcpu;
-vcpu_uninit:
-	kvm_vcpu_uninit(vcpu);
-free_vcpu:
-	kmem_cache_free(kvm_vcpu_cache, vcpu);
-out:
-	return ERR_PTR(err);
+	return create_hyp_mappings(vcpu, vcpu + 1, PAGE_HYP);
 }
 
 void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
@@ -330,8 +307,6 @@ void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
 	kvm_mmu_free_memory_caches(vcpu);
 	kvm_timer_vcpu_terminate(vcpu);
 	kvm_pmu_vcpu_destroy(vcpu);
-	kvm_vcpu_uninit(vcpu);
-	kmem_cache_free(kvm_vcpu_cache, vcpu);
 }
 
 int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 62ba25e44189..c84df40518c4 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -378,6 +378,9 @@ EXPORT_SYMBOL_GPL(kvm_vcpu_uninit);
 void kvm_vcpu_destroy(struct kvm_vcpu *vcpu)
 {
 	kvm_arch_vcpu_destroy(vcpu);
+
+	kvm_vcpu_uninit(vcpu);
+	kmem_cache_free(kvm_vcpu_cache, vcpu);
 }
 EXPORT_SYMBOL_GPL(kvm_vcpu_destroy);
 
@@ -2738,12 +2741,20 @@ static int kvm_vm_ioctl_create_vcpu(struct kvm *kvm, u32 id)
 	if (r)
 		goto vcpu_decrement;
 
-	vcpu = kvm_arch_vcpu_create(kvm, id);
-	if (IS_ERR(vcpu)) {
-		r = PTR_ERR(vcpu);
+	vcpu = kmem_cache_zalloc(kvm_vcpu_cache, GFP_KERNEL);
+	if (!vcpu) {
+		r = -ENOMEM;
 		goto vcpu_decrement;
 	}
 
+	r = kvm_vcpu_init(vcpu, kvm, id);
+	if (r)
+		goto vcpu_free;
+
+	r = kvm_arch_vcpu_create(vcpu);
+	if (r)
+		goto vcpu_uninit;
+
 	preempt_notifier_init(&vcpu->preempt_notifier, &kvm_preempt_ops);
 
 	r = kvm_arch_vcpu_setup(vcpu);
@@ -2787,6 +2798,10 @@ unlock_vcpu_destroy:
 	debugfs_remove_recursive(vcpu->debugfs_dentry);
 vcpu_destroy:
 	kvm_arch_vcpu_destroy(vcpu);
+vcpu_uninit:
+	kvm_vcpu_uninit(vcpu);
+vcpu_free:
+	kmem_cache_free(kvm_vcpu_cache, vcpu);
 vcpu_decrement:
 	mutex_lock(&kvm->lock);
 	kvm->created_vcpus--;