Re: [RFC PATCH 07/45] KVM: arm/arm64: vgic-new: Add vgic GICv2 change_affinity

Christoffer Dall
2016-03-30T09:29:42Z

On Fri, Mar 25, 2016 at 02:04:30AM +0000, Andre Przywara wrote:
> From: Christoffer Dall <christoffer.dall@linaro.org>
>
> Introduce vgic-v2.c to contain GICv2 specific functions.
> Add vgic_v2_irq_change_affinity() to change the target VCPU of a
> particular interrupt.
>
> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
> Signed-off-by: Eric Auger <eric.auger@linaro.org>
> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
> Signed-off-by: Andre Przywara <marc.zyngier@arm.com>
> ---
> virt/kvm/arm/vgic/vgic-v2.c | 40 ++++++++++++++++++++++++++++++++++++++++
> virt/kvm/arm/vgic/vgic.h | 2 ++
> 2 files changed, 42 insertions(+)
> create mode 100644 virt/kvm/arm/vgic/vgic-v2.c
>
> diff --git a/virt/kvm/arm/vgic/vgic-v2.c b/virt/kvm/arm/vgic/vgic-v2.c
> new file mode 100644
> index 0000000..0bf6f27
> --- /dev/null
> +++ b/virt/kvm/arm/vgic/vgic-v2.c
> @@ -0,0 +1,40 @@
> +/*
> + * Copyright (C) 2015, 2016 ARM Ltd.
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> + * GNU General Public License for more details.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program. If not, see <http://www.gnu.org/licenses/>.
> + */
> +
> +#include <linux/kvm.h>
> +#include <linux/kvm_host.h>
> +
> +#include "vgic.h"
> +
> +void vgic_v2_irq_change_affinity(struct kvm *kvm, u32 intid, u8 new_targets)
> +{
> + struct vgic_dist *dist = &kvm->arch.vgic;
> + struct vgic_irq *irq;
> + int target;
> +
> + BUG_ON(intid <= VGIC_MAX_PRIVATE);
> + BUG_ON(dist->vgic_model != KVM_DEV_TYPE_ARM_VGIC_V2);

we can probably get rid of the last BUG_ON here.

> +
> + irq = vgic_get_irq(kvm, NULL, intid);
> +
> + spin_lock(&irq->irq_lock);
> + irq->targets = new_targets;
> +
> + target = ffs(irq->targets);
> + target = target ? (target - 1) : 0;
> + irq->target_vcpu = kvm_get_vcpu(kvm, target);
> + spin_unlock(&irq->irq_lock);
> +}
> diff --git a/virt/kvm/arm/vgic/vgic.h b/virt/kvm/arm/vgic/vgic.h
> index e9f4aa6..b2faf00 100644
> --- a/virt/kvm/arm/vgic/vgic.h
> +++ b/virt/kvm/arm/vgic/vgic.h
> @@ -20,4 +20,6 @@ struct vgic_irq *vgic_get_irq(struct kvm *kvm, struct kvm_vcpu *vcpu,
> u32 intid);
> bool vgic_queue_irq(struct kvm *kvm, struct vgic_irq *irq);
>
> +void vgic_v2_irq_change_affinity(struct kvm *kvm, u32 intid, u8 target);
> +
> #endif
> --
> 2.7.3
>