Re: [PATCH 3/5] arm/arm64: KVM: Add (new) vgic_initialized macro

Eric Auger
2014-12-10T10:28:58Z

On 12/09/2014 04:44 PM, Christoffer Dall wrote:
> Some code paths will need to check to see if the internal state of the
> vgic has been initialized (such as when creating new VCPUs), so
> introduce such a macro that checks the nr_cpus field which is set when
> the vgic has been initialized.
>
> Also set nr_cpus = 0 in kvm_vgic_destroy, because the error path in
> vgic_init() will call this function, and code should never errornously
> assume the vgic to be properly initialized after an error.
>
> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
> ---
> include/kvm/arm_vgic.h | 6 ++++++
> virt/kvm/arm/vgic.c | 1 +
> 2 files changed, 7 insertions(+)
>
> diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h
> index 3e262b9..ac4888d 100644
> --- a/include/kvm/arm_vgic.h
> +++ b/include/kvm/arm_vgic.h
> @@ -287,6 +287,7 @@ bool vgic_handle_mmio(struct kvm_vcpu *vcpu, struct kvm_run *run,
> struct kvm_exit_mmio *mmio);
>
> #define irqchip_in_kernel(k) (!!((k)->arch.vgic.in_kernel))
> +#define vgic_initialized(k) (!!((k)->arch.vgic.nr_cpus))
> #define vgic_ready(k) ((k)->arch.vgic.ready)
>
> int vgic_v2_probe(struct device_node *vgic_node,
> @@ -369,6 +370,11 @@ static inline int irqchip_in_kernel(struct kvm *kvm)
> return 0;
> }
>
> +static inline bool vgic_initialized(struct kvm *kvm)
> +{
> + return true;
> +}
> +
> static inline bool vgic_ready(struct kvm *kvm)
> {
> return true;
> diff --git a/virt/kvm/arm/vgic.c b/virt/kvm/arm/vgic.c
> index 6293349..c98cc6b 100644
> --- a/virt/kvm/arm/vgic.c
> +++ b/virt/kvm/arm/vgic.c
> @@ -1774,6 +1774,7 @@ void kvm_vgic_destroy(struct kvm *kvm)
> dist->irq_spi_cpu = NULL;
> dist->irq_spi_target = NULL;
> dist->irq_pending_on_cpu = NULL;
> + dist->nr_cpus = 0;
Reviewed-by: Eric Auger <eric.auger@linaro.org>
we could use that new vgic_initialized at the entry of vgic_init instead
of testing dist->nr_cpus, hence introducing one user.

Eric
> }
>
> /*
>