diff options
| author | Suthikulpanit, Suravee <Suravee.Suthikulpanit@amd.com> | 2019-05-03 06:38:53 -0700 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2019-06-04 19:27:31 +0200 |
| commit | 0532dd52dfec0cf774188d3e692d50c197bc4210 (patch) | |
| tree | f4221640b26b6a23b6d531ea92e692e6d4c364d6 | |
| parent | b6c4bc659c6f3b7f2b6c3a330ae36f1cfd69d73e (diff) | |
| download | lwn-0532dd52dfec0cf774188d3e692d50c197bc4210.tar.gz lwn-0532dd52dfec0cf774188d3e692d50c197bc4210.zip | |
kvm: svm/avic: Do not send AVIC doorbell to self
AVIC doorbell is used to notify a running vCPU that interrupts
has been injected into the vCPU AVIC backing page. Current logic
checks only if a VCPU is running before sending a doorbell.
However, the doorbell is not necessary if the destination
CPU is itself.
Add logic to check currently running CPU before sending doorbell.
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Reviewed-by: Alexander Graf <graf@amazon.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| -rw-r--r-- | arch/x86/kvm/svm.c | 11 |
1 files changed, 7 insertions, 4 deletions
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index a7ea34bed3fe..c56f40d430e5 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -5163,10 +5163,13 @@ static void svm_deliver_avic_intr(struct kvm_vcpu *vcpu, int vec) kvm_lapic_set_irr(vec, vcpu->arch.apic); smp_mb__after_atomic(); - if (avic_vcpu_is_running(vcpu)) - wrmsrl(SVM_AVIC_DOORBELL, - kvm_cpu_get_apicid(vcpu->cpu)); - else + if (avic_vcpu_is_running(vcpu)) { + int cpuid = vcpu->cpu; + + if (cpuid != get_cpu()) + wrmsrl(SVM_AVIC_DOORBELL, kvm_cpu_get_apicid(cpuid)); + put_cpu(); + } else kvm_vcpu_wake_up(vcpu); } |