On 20/03/17 10:58, Christoffer Dall wrote:
> Implement early initialization for both the distributor and the CPU
> interfaces. The basic idea is that even though the VGIC is not
> functional or not requested from user space, the critical path of the
> run loop can still call VGIC functions that just won't do anything,
> without them having to check additional initialization flags to ensure
> they don't look at uninitialized data structures.
>
> Signed-off-by: Christoffer Dall <cdall@xxxxxxxxxx>
> ---
> virt/kvm/arm/vgic/vgic-init.c | 96 +++++++++++++++++++++++++------------------
> 1 file changed, 56 insertions(+), 40 deletions(-)
>
> diff --git a/virt/kvm/arm/vgic/vgic-init.c b/virt/kvm/arm/vgic/vgic-init.c
> index 3762fd1..25fd1b9 100644
> --- a/virt/kvm/arm/vgic/vgic-init.c
> +++ b/virt/kvm/arm/vgic/vgic-init.c
> @@ -24,7 +24,12 @@
>
> /*
> * Initialization rules: there are multiple stages to the vgic
> - * initialization, both for the distributor and the CPU interfaces.
> + * initialization, both for the distributor and the CPU interfaces. The basic
> + * idea is that even though the VGIC is not functional or not requested from
> + * user space, the critical path of the run loop can still call VGIC functions
> + * that just won't do anything, without them having to check additional
> + * initialization flags to ensure they don't look at uninitialized data
> + * structures.
> *
> * Distributor:
> *
> @@ -39,23 +44,67 @@
> *
> * CPU Interface:
> *
> - * - kvm_vgic_cpu_early_init(): initialization of static data that
> + * - kvm_vgic_vcpu_early_init(): initialization of static data that
> * doesn't depend on any sizing information or emulation type. No
> * allocation is allowed there.
> */
>
> /* EARLY INIT */
>
> -/*
> - * Those 2 functions should not be needed anymore but they
> - * still are called from arm.c
> +/**
> + * kvm_vgic_early_init() - Initialize static VGIC VCPU data structures
> + * @kvm: The VM whose VGIC districutor should be initialized
> + *
> + * Only do initialization of static structures that don't require any
> + * allocation or sizing information from userspace. vgic_init() called
> + * kvm_vgic_dist_init() which takes care of the rest.
> */
> void kvm_vgic_early_init(struct kvm *kvm)
> {
> + struct vgic_dist *dist = &kvm->arch.vgic;
> +
> + INIT_LIST_HEAD(&dist->lpi_list_head);
> + spin_lock_init(&dist->lpi_list_lock);
> }
>
> +/**
> + * kvm_vgic_vcpu_early_init() - Initialize static VGIC VCPU data structures
> + * @vcpu: The VCPU whose VGIC data structures whould be initialized
> + *
> + * Only do initialization, but do not actually enable the VGIC CPU interface
> + * yet.
> + */
> void kvm_vgic_vcpu_early_init(struct kvm_vcpu *vcpu)
> {
> + struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
> + int i;
> +
> + INIT_LIST_HEAD(&vgic_cpu->ap_list_head);
> + spin_lock_init(&vgic_cpu->ap_list_lock);
> +
> + /*
> + * Enable and configure all SGIs to be edge-triggered and
> + * configure all PPIs as level-triggered.
> + */
> + for (i = 0; i < VGIC_NR_PRIVATE_IRQS; i++) {
> + struct vgic_irq *irq = &vgic_cpu->private_irqs[i];
> +
> + INIT_LIST_HEAD(&irq->ap_list);
> + spin_lock_init(&irq->irq_lock);
> + irq->intid = i;
> + irq->vcpu = NULL;
> + irq->target_vcpu = vcpu;
> + irq->targets = 1U << vcpu->vcpu_id;
> + kref_init(&irq->refcount);
> + if (vgic_irq_is_sgi(i)) {
> + /* SGIs */
> + irq->enabled = 1;
> + irq->config = VGIC_CONFIG_EDGE;
> + } else {
> + /* PPIs */
> + irq->config = VGIC_CONFIG_LEVEL;
> + }
> + }
> }
>
> /* CREATION */
> @@ -148,9 +197,6 @@ static int kvm_vgic_dist_init(struct kvm *kvm, unsigned int nr_spis)
> struct kvm_vcpu *vcpu0 = kvm_get_vcpu(kvm, 0);
> int i;
>
> - INIT_LIST_HEAD(&dist->lpi_list_head);
> - spin_lock_init(&dist->lpi_list_lock);
> -
> dist->spis = kcalloc(nr_spis, sizeof(struct vgic_irq), GFP_KERNEL);
> if (!dist->spis)
> return -ENOMEM;
> @@ -181,41 +227,11 @@ static int kvm_vgic_dist_init(struct kvm *kvm, unsigned int nr_spis)
> }
>
> /**
> - * kvm_vgic_vcpu_init: initialize the vcpu data structures and
> - * enable the VCPU interface
> - * @vcpu: the VCPU which's VGIC should be initialized
> + * kvm_vgic_vcpu_init() - Enable the VCPU interface
> + * @vcpu: the VCPU which's VGIC should be enabled
> */
> static void kvm_vgic_vcpu_init(struct kvm_vcpu *vcpu)
> {
> - struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
> - int i;
> -
> - INIT_LIST_HEAD(&vgic_cpu->ap_list_head);
> - spin_lock_init(&vgic_cpu->ap_list_lock);
> -
> - /*
> - * Enable and configure all SGIs to be edge-triggered and
> - * configure all PPIs as level-triggered.
> - */
> - for (i = 0; i < VGIC_NR_PRIVATE_IRQS; i++) {
> - struct vgic_irq *irq = &vgic_cpu->private_irqs[i];
> -
> - INIT_LIST_HEAD(&irq->ap_list);
> - spin_lock_init(&irq->irq_lock);
> - irq->intid = i;
> - irq->vcpu = NULL;
> - irq->target_vcpu = vcpu;
> - irq->targets = 1U << vcpu->vcpu_id;
> - kref_init(&irq->refcount);
> - if (vgic_irq_is_sgi(i)) {
> - /* SGIs */
> - irq->enabled = 1;
> - irq->config = VGIC_CONFIG_EDGE;
> - } else {
> - /* PPIs */
> - irq->config = VGIC_CONFIG_LEVEL;
> - }
> - }
> if (kvm_vgic_global_state.type == VGIC_V2)
> vgic_v2_enable(vcpu);
> else
>
Since this function is now about enabling the vgic on a given vcpu,
shouldn't the name reflect this? Other than that:
Acked-by: Marc Zyngier <marc.zyngier@xxxxxxx>
M.
--
Jazz is not dead. It just smells funny...
