KVM: x86: Change __kvm_apic_update_irr() to also return if max IRR updated
This commit doesn't change semantics.
It is done as a preparation for future commits.
Signed-off-by: Liran Alon <liran.alon@oracle.com>
Reviewed-by: Nikita Leshenko <nikita.leshchenko@oracle.com>
Reviewed-by: Liam Merwick <liam.merwick@oracle.com>
Signed-off-by: Liam Merwick <liam.merwick@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index 0928608..924ac8c 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -364,32 +364,41 @@ static u8 count_vectors(void *bitmap)
return count;
}
-int __kvm_apic_update_irr(u32 *pir, void *regs)
+bool __kvm_apic_update_irr(u32 *pir, void *regs, int *max_irr)
{
u32 i, vec;
- u32 pir_val, irr_val;
- int max_irr = -1;
+ u32 pir_val, irr_val, prev_irr_val;
+ int max_updated_irr;
+
+ max_updated_irr = -1;
+ *max_irr = -1;
for (i = vec = 0; i <= 7; i++, vec += 32) {
pir_val = READ_ONCE(pir[i]);
irr_val = *((u32 *)(regs + APIC_IRR + i * 0x10));
if (pir_val) {
+ prev_irr_val = irr_val;
irr_val |= xchg(&pir[i], 0);
*((u32 *)(regs + APIC_IRR + i * 0x10)) = irr_val;
+ if (prev_irr_val != irr_val) {
+ max_updated_irr =
+ __fls(irr_val ^ prev_irr_val) + vec;
+ }
}
if (irr_val)
- max_irr = __fls(irr_val) + vec;
+ *max_irr = __fls(irr_val) + vec;
}
- return max_irr;
+ return ((max_updated_irr != -1) &&
+ (max_updated_irr == *max_irr));
}
EXPORT_SYMBOL_GPL(__kvm_apic_update_irr);
-int kvm_apic_update_irr(struct kvm_vcpu *vcpu, u32 *pir)
+bool kvm_apic_update_irr(struct kvm_vcpu *vcpu, u32 *pir, int *max_irr)
{
struct kvm_lapic *apic = vcpu->arch.apic;
- return __kvm_apic_update_irr(pir, apic->regs);
+ return __kvm_apic_update_irr(pir, apic->regs, max_irr);
}
EXPORT_SYMBOL_GPL(kvm_apic_update_irr);