Re: [PATCH v2] KVM: arm/arm64 : add lpi info in vgic-debug

[Marc Zyngier]

On 23/03/18 23:01, Peng Hao wrote:
> Add lpi debug info to vgic-stat.
> the printed info like this:
>     SPI  287      0 000001        0        0   0 160      -1
>     LPI 8192      2 000100        0        0   0 160      -1
> 
> Signed-off-by: Peng Hao <peng.hao2@xxxxxxxxxx>
> ---
>  virt/kvm/arm/vgic/vgic-debug.c | 56 ++++++++++++++++++++++++++++++++++++++----
>  1 file changed, 51 insertions(+), 5 deletions(-)
> 
> diff --git a/virt/kvm/arm/vgic/vgic-debug.c b/virt/kvm/arm/vgic/vgic-debug.c
> index 10b3817..cb85550 100644
> --- a/virt/kvm/arm/vgic/vgic-debug.c
> +++ b/virt/kvm/arm/vgic/vgic-debug.c
> @@ -36,9 +36,12 @@
>  struct vgic_state_iter {
>  	int nr_cpus;
>  	int nr_spis;
> +	int nr_lpis;
>  	int dist_id;
>  	int vcpu_id;
>  	int intid;
> +	int lpi_print_count;
> +	struct vgic_irq **lpi_irqs;
>  };
>  
>  static void iter_next(struct vgic_state_iter *iter)
> @@ -52,6 +55,35 @@ static void iter_next(struct vgic_state_iter *iter)
>  	if (iter->intid == VGIC_NR_PRIVATE_IRQS &&
>  	    ++iter->vcpu_id < iter->nr_cpus)
>  		iter->intid = 0;
> +
> +	if (iter->intid >= VGIC_NR_PRIVATE_IRQS + iter->nr_spis) {
> +		if (iter->lpi_print_count < iter->nr_lpis)
> +			iter->intid = iter->lpi_irqs[iter->lpi_print_count]->intid;
> +		iter->lpi_print_count++;
> +	}
> +}
> +
> +static void vgic_debug_get_lpis(struct kvm *kvm, struct vgic_state_iter *iter)
> +{
> +	struct vgic_dist *dist = &kvm->arch.vgic;
> +	int i = 0;
> +	struct vgic_irq *irq = NULL, **lpi_irqs;
> +
> +	iter->nr_lpis = dist->lpi_list_count;
> +	lpi_irqs = kmalloc_array(iter->nr_lpis, sizeof(irq), GFP_KERNEL);
> +	if (!lpi_irqs) {
> +		iter->nr_lpis = 0;
> +		return;
> +	}
> +	spin_lock(&dist->lpi_list_lock);
> +	list_for_each_entry(irq, &dist->lpi_list_head, lpi_list) {
> +		vgic_get_irq_kref(irq);
> +		if (i < iter->nr_lpis)
> +			lpi_irqs[i++] = irq;
> +	}
> +	iter->nr_lpis = i;
> +	spin_unlock(&dist->lpi_list_lock);
> +	iter->lpi_irqs = lpi_irqs;

I've already explained why I didn't like this construct.

I still don't like it.

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