[PATCH] Add valid_vcpu() helper.

[PATCH] Add valid_vcpu() helper.

[James Morris]

Consolidate the logic for checking whether a vcpu index is valid.  Also, 
use likely(), as a valid value should be the overwhelmingly common case.

Signed-off-by: James Morris <jmorris-gx6/JNMH7DfYtjvyW6yDsg@public.gmane.org>
---
 drivers/kvm/kvm_main.c |   23 ++++++++++++++---------
 1 files changed, 14 insertions(+), 9 deletions(-)

diff --git a/drivers/kvm/kvm_main.c b/drivers/kvm/kvm_main.c
index b6b8a41..ad454e5 100644
--- a/drivers/kvm/kvm_main.c
+++ b/drivers/kvm/kvm_main.c
@@ -72,6 +72,11 @@ #define CR4_RESEVED_BITS (~((1ULL << 11)
 #define CR8_RESEVED_BITS (~0x0fULL)
 #define EFER_RESERVED_BITS 0xfffffffffffff2fe
 
+static inline int valid_vcpu(int n)
+{
+	return likely(n >= 0 && n < KVM_MAX_VCPUS);
+}
+
 struct vmx_msr_entry *find_msr_entry(struct kvm_vcpu *vcpu, u32 msr)
 {
 	int i;
@@ -506,7 +511,7 @@ static int kvm_dev_ioctl_create_vcpu(str
 	struct kvm_vcpu *vcpu;
 
 	r = -EINVAL;
-	if (n < 0 || n >= KVM_MAX_VCPUS)
+	if (!valid_vcpu(n))
 		goto out;
 
 	vcpu = &kvm->vcpus[n];
@@ -1197,7 +1202,7 @@ static int kvm_dev_ioctl_run(struct kvm 
 	struct kvm_vcpu *vcpu;
 	int r;
 
-	if (kvm_run->vcpu < 0 || kvm_run->vcpu >= KVM_MAX_VCPUS)
+	if (!valid_vcpu(kvm_run->vcpu))
 		return -EINVAL;
 
 	vcpu = vcpu_load(kvm, kvm_run->vcpu);
@@ -1226,7 +1231,7 @@ static int kvm_dev_ioctl_get_regs(struct
 {
 	struct kvm_vcpu *vcpu;
 
-	if (regs->vcpu < 0 || regs->vcpu >= KVM_MAX_VCPUS)
+	if (!valid_vcpu(regs->vcpu))
 		return -EINVAL;
 
 	vcpu = vcpu_load(kvm, regs->vcpu);
@@ -1272,7 +1277,7 @@ static int kvm_dev_ioctl_set_regs(struct
 {
 	struct kvm_vcpu *vcpu;
 
-	if (regs->vcpu < 0 || regs->vcpu >= KVM_MAX_VCPUS)
+	if (!valid_vcpu(regs->vcpu))
 		return -EINVAL;
 
 	vcpu = vcpu_load(kvm, regs->vcpu);
@@ -1319,7 +1324,7 @@ static int kvm_dev_ioctl_get_sregs(struc
 	struct kvm_vcpu *vcpu;
 	struct descriptor_table dt;
 
-	if (sregs->vcpu < 0 || sregs->vcpu >= KVM_MAX_VCPUS)
+	if (!valid_vcpu(sregs->vcpu))
 		return -EINVAL;
 	vcpu = vcpu_load(kvm, sregs->vcpu);
 	if (!vcpu)
@@ -1371,7 +1376,7 @@ static int kvm_dev_ioctl_set_sregs(struc
 	int i;
 	struct descriptor_table dt;
 
-	if (sregs->vcpu < 0 || sregs->vcpu >= KVM_MAX_VCPUS)
+	if (!valid_vcpu(sregs->vcpu))
 		return -EINVAL;
 	vcpu = vcpu_load(kvm, sregs->vcpu);
 	if (!vcpu)
@@ -1462,7 +1467,7 @@ static int __msr_io(struct kvm *kvm, str
 	struct kvm_vcpu *vcpu;
 	int i;
 
-	if (msrs->vcpu < 0 || msrs->vcpu >= KVM_MAX_VCPUS)
+	if (!valid_vcpu(msrs->vcpu))
 		return -EINVAL;
 
 	vcpu = vcpu_load(kvm, msrs->vcpu);
@@ -1555,7 +1560,7 @@ static int kvm_dev_ioctl_interrupt(struc
 {
 	struct kvm_vcpu *vcpu;
 
-	if (irq->vcpu < 0 || irq->vcpu >= KVM_MAX_VCPUS)
+	if (!valid_vcpu(irq->vcpu))
 		return -EINVAL;
 	if (irq->irq < 0 || irq->irq >= 256)
 		return -EINVAL;
@@ -1577,7 +1582,7 @@ static int kvm_dev_ioctl_debug_guest(str
 	struct kvm_vcpu *vcpu;
 	int r;
 
-	if (dbg->vcpu < 0 || dbg->vcpu >= KVM_MAX_VCPUS)
+	if (!valid_vcpu(dbg->vcpu))
 		return -EINVAL;
 	vcpu = vcpu_load(kvm, dbg->vcpu);
 	if (!vcpu)
-- 
1.4.2.4


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Re: [PATCH] Add valid_vcpu() helper.

[Avi Kivity]

James Morris wrote:
> Consolidate the logic for checking whether a vcpu index is valid.  Also, 
> use likely(), as a valid value should be the overwhelmingly common case.
>
>   

Applied, thanks.

-- 
error compiling committee.c: too many arguments to function


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