Marc Zyngier <marc.zyng...@arm.com> writes:

> As we now inject the timer interrupt when we're about to enter
> the guest, it makes a lot more sense to make sure this happens
> before the vgic code queues the pending interrupts.
>
> Otherwise, we get the interrupt on the following exit, which is
> not great for latency (and leads to all kind of bizarre issues
> when using with active interrupts at the HW level).
>
> Signed-off-by: Marc Zyngier <marc.zyng...@arm.com>
> ---
>  arch/arm/kvm/arm.c | 8 +++++---
>  1 file changed, 5 insertions(+), 3 deletions(-)
>
> diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c
> index d9631ec..46db690 100644
> --- a/arch/arm/kvm/arm.c
> +++ b/arch/arm/kvm/arm.c
> @@ -529,9 +529,10 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, 
> struct kvm_run *run)
>               if (vcpu->arch.pause)
>                       vcpu_pause(vcpu);
>  
> -             kvm_vgic_flush_hwstate(vcpu);
>               kvm_timer_flush_hwstate(vcpu);
>  
> +             kvm_vgic_flush_hwstate(vcpu);
> +
>               local_irq_disable();
>  
>               /*
> @@ -544,8 +545,8 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct 
> kvm_run *run)
>  
>               if (ret <= 0 || need_new_vmid_gen(vcpu->kvm)) {
>                       local_irq_enable();
> -                     kvm_timer_sync_hwstate(vcpu);
>                       kvm_vgic_sync_hwstate(vcpu);
> +                     kvm_timer_sync_hwstate(vcpu);
>                       continue;
>               }
>  
> @@ -577,9 +578,10 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, 
> struct kvm_run *run)
>                * Back from guest
>                *************************************************************/
>  
> -             kvm_timer_sync_hwstate(vcpu);
>               kvm_vgic_sync_hwstate(vcpu);
>  
> +             kvm_timer_sync_hwstate(vcpu);
> +
>               ret = handle_exit(vcpu, run, ret);
>       }

Reviewed-by: Alex Bennée <alex.ben...@linaro.org>

-- 
Alex Bennée
--
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