[PATCH] KVM: arm/arm64: prefer IS_ENABLED to a static variable

Paolo Bonzini
2015-03-05T11:20:11Z

IS_ENABLED gives compile-time checking and keeps the code clearer.

The one exception is inside kvm_vm_ioctl_check_extension, where
the established idiom is to wrap the case labels with an #ifdef.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
--
Untested...
---
arch/arm/kvm/arm.c | 17 +++++------------
1 file changed, 5 insertions(+), 12 deletions(-)

diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c
index 07e7eb1d7ab6..706769fb0f2e 100644
--- a/arch/arm/kvm/arm.c
+++ b/arch/arm/kvm/arm.c
@@ -61,8 +61,6 @@ static atomic64_t kvm_vmid_gen = ATOMIC64_INIT(1);
static u8 kvm_next_vmid;
static DEFINE_SPINLOCK(kvm_vmid_lock);

-static bool vgic_present;
-
static void kvm_arm_set_running_vcpu(struct kvm_vcpu *vcpu)
{
BUG_ON(preemptible());
@@ -172,9 +170,9 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
{
int r;
switch (ext) {
+#ifdef CONFIG_KVM_ARM_VGIC
case KVM_CAP_IRQCHIP:
- r = vgic_present;
- break;
+#endif
case KVM_CAP_DEVICE_CTRL:
case KVM_CAP_USER_MEMORY:
case KVM_CAP_SYNC_MMU:
@@ -831,7 +829,7 @@ static int kvm_vm_ioctl_set_device_addr(struct kvm *kvm,

switch (dev_id) {
case KVM_ARM_DEVICE_VGIC_V2:
- if (!vgic_present)
+ if (!IS_ENABLED(CONFIG_KVM_ARM_VGIC))
return -ENXIO;
return kvm_vgic_addr(kvm, type, &dev_addr->addr, true);
default:
@@ -847,10 +845,9 @@ long kvm_arch_vm_ioctl(struct file *filp,

switch (ioctl) {
case KVM_CREATE_IRQCHIP: {
- if (vgic_present)
- return kvm_vgic_create(kvm, KVM_DEV_TYPE_ARM_VGIC_V2);
- else
+ if (!IS_ENABLED(CONFIG_KVM_ARM_VGIC))
return -ENXIO;
+ return kvm_vgic_create(kvm, KVM_DEV_TYPE_ARM_VGIC_V2);
}
case KVM_ARM_SET_DEVICE_ADDR: {
struct kvm_arm_device_addr dev_addr;
@@ -1035,10 +1032,6 @@ static int init_hyp_mode(void)
if (err)
goto out_free_context;

-#ifdef CONFIG_KVM_ARM_VGIC
- vgic_present = true;
-#endif
-
/*
* Init HYP architected timer support
*/
--
2.3.0