Hi Shannon,
On 19/11/14 10:11, Shannon Zhao wrote:
> When call kvm_vgic_inject_irq to inject interrupt, we can known which
> vcpu the interrupt for by the irq_num and the cpuid. So we should just
> kick this vcpu to avoid iterating through all.
>
> Signed-off-by: Shannon Zhao <zhaoshenglong@xxxxxxxxxx>
> ---
> virt/kvm/arm/vgic.c | 15 ++++++++++-----
> 1 files changed, 10 insertions(+), 5 deletions(-)
>
> diff --git a/virt/kvm/arm/vgic.c b/virt/kvm/arm/vgic.c
> index 82db9d6..a032c79 100644
> --- a/virt/kvm/arm/vgic.c
> +++ b/virt/kvm/arm/vgic.c
> @@ -1607,7 +1607,7 @@ static int vgic_validate_injection(struct kvm_vcpu *vcpu, int irq, int level)
> }
> }
>
> -static bool vgic_update_irq_pending(struct kvm *kvm, int cpuid,
> +static int vgic_update_irq_pending(struct kvm *kvm, int cpuid,
> unsigned int irq_num, bool level)
> {
> struct vgic_dist *dist = &kvm->arch.vgic;
> @@ -1672,7 +1672,7 @@ static bool vgic_update_irq_pending(struct kvm *kvm, int cpuid,
> out:
> spin_unlock(&dist->lock);
>
> - return ret;
> + return ret ? cpuid : -EINVAL;
> }
>
> /**
> @@ -1692,9 +1692,14 @@ out:
> int kvm_vgic_inject_irq(struct kvm *kvm, int cpuid, unsigned int irq_num,
> bool level)
> {
> - if (likely(vgic_initialized(kvm)) &&
> - vgic_update_irq_pending(kvm, cpuid, irq_num, level))
> - vgic_kick_vcpus(kvm);
> + int vcpu_id;
> +
> + if (likely(vgic_initialized(kvm))) {
> + vcpu_id = vgic_update_irq_pending(kvm, cpuid, irq_num, level);
> + if (vcpu_id >= 0)
> + /* kick the specified vcpu */
> + kvm_vcpu_kick(kvm_get_vcpu(kvm, vcpu_id));
> + }
>
> return 0;
> }
>
This looks much better. Do you have actual data showing how much
improvement this brings?
Thanks,
M.
--
Jazz is not dead. It just smells funny...
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