Re: [PATCH v5 16/26] KVM: arm/arm64: GICv4: Propagate property updates to VLPIs

Marc Zyngier
2017-11-08T15:08:36Z

On 07/11/17 21:28, Auger Eric wrote:
> Hi Marc,
>
> On 27/10/2017 16:28, Marc Zyngier wrote:
>> Upon updating a property, we propagate it all the way to the physical
>> ITS, and ask for an INV command to be executed there.
>>
>> Acked-by: Christoffer Dall <cdall@linaro.org>
>> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
>> ---
>> virt/kvm/arm/vgic/vgic-its.c | 3 +++
>> 1 file changed, 3 insertions(+)
>>
>> diff --git a/virt/kvm/arm/vgic/vgic-its.c b/virt/kvm/arm/vgic/vgic-its.c
>> index 0b7e648e7a0c..2e77c7c83942 100644
>> --- a/virt/kvm/arm/vgic/vgic-its.c
>> +++ b/virt/kvm/arm/vgic/vgic-its.c
>> @@ -296,6 +296,9 @@ static int update_lpi_config(struct kvm *kvm, struct vgic_irq *irq,
>> spin_unlock(&irq->irq_lock);
>> }
>>
>> + if (irq->hw)
>> + return its_prop_update_vlpi(irq->host_irq, prop, true);
>> +
>> return 0;
>> }
> I am confused by the vgic_queue_irq_unlock() on the "hw" path. Why is it
> needed in hw mode?

It's not. I guess we could bypass this altogether and take a short cut
after having updated the priority and enabled fields.

Thanks,

M.
--
Jazz is not dead. It just smells funny...