Re: [PATCH] KVM: APIC: add helper func to remove duplicate code in kvm_pv_send_ipi

From: Paolo Bonzini
Date: Mon Nov 11 2019 - 09:10:24 EST


On 09/11/19 10:46, linmiaohe wrote:
> From: Miaohe Lin <linmiaohe@xxxxxxxxxx>
>
> There are some duplicate code in kvm_pv_send_ipi when deal with ipi
> bitmap. Add helper func to remove it, and eliminate odd out label,
> get rid of unnecessary kvm_lapic_irq field init and so on.
>
> Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx>
> ---
> arch/x86/kvm/lapic.c | 65 ++++++++++++++++++++------------------------
> 1 file changed, 29 insertions(+), 36 deletions(-)
>
> diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
> index b29d00b661ff..2f8f10103f5f 100644
> --- a/arch/x86/kvm/lapic.c
> +++ b/arch/x86/kvm/lapic.c
> @@ -557,60 +557,53 @@ int kvm_apic_set_irq(struct kvm_vcpu *vcpu, struct kvm_lapic_irq *irq,
> irq->level, irq->trig_mode, dest_map);
> }
>
> +static int __pv_send_ipi(unsigned long *ipi_bitmap, struct kvm_apic_map *map,
> + struct kvm_lapic_irq *irq, u32 min)
> +{
> + int i, count = 0;
> + struct kvm_vcpu *vcpu;
> +
> + if (min > map->max_apic_id)
> + return 0;
> +
> + for_each_set_bit(i, ipi_bitmap,
> + min((u32)BITS_PER_LONG, (map->max_apic_id - min + 1))) {
> + if (map->phys_map[min + i]) {
> + vcpu = map->phys_map[min + i]->vcpu;
> + count += kvm_apic_set_irq(vcpu, irq, NULL);
> + }
> + }
> +
> + return count;
> +}
> +
> int kvm_pv_send_ipi(struct kvm *kvm, unsigned long ipi_bitmap_low,
> unsigned long ipi_bitmap_high, u32 min,
> unsigned long icr, int op_64_bit)
> {
> - int i;
> struct kvm_apic_map *map;
> - struct kvm_vcpu *vcpu;
> struct kvm_lapic_irq irq = {0};
> int cluster_size = op_64_bit ? 64 : 32;
> - int count = 0;
> + int count;
> +
> + if (icr & (APIC_DEST_MASK | APIC_SHORT_MASK))
> + return -KVM_EINVAL;
>
> irq.vector = icr & APIC_VECTOR_MASK;
> irq.delivery_mode = icr & APIC_MODE_MASK;
> irq.level = (icr & APIC_INT_ASSERT) != 0;
> irq.trig_mode = icr & APIC_INT_LEVELTRIG;
>
> - if (icr & APIC_DEST_MASK)
> - return -KVM_EINVAL;
> - if (icr & APIC_SHORT_MASK)
> - return -KVM_EINVAL;
> -
> rcu_read_lock();
> map = rcu_dereference(kvm->arch.apic_map);
>
> - if (unlikely(!map)) {
> - count = -EOPNOTSUPP;
> - goto out;
> + count = -EOPNOTSUPP;
> + if (likely(map)) {
> + count = __pv_send_ipi(&ipi_bitmap_low, map, &irq, min);
> + min += cluster_size;
> + count += __pv_send_ipi(&ipi_bitmap_high, map, &irq, min);
> }
>
> - if (min > map->max_apic_id)
> - goto out;
> - /* Bits above cluster_size are masked in the caller. */
> - for_each_set_bit(i, &ipi_bitmap_low,
> - min((u32)BITS_PER_LONG, (map->max_apic_id - min + 1))) {
> - if (map->phys_map[min + i]) {
> - vcpu = map->phys_map[min + i]->vcpu;
> - count += kvm_apic_set_irq(vcpu, &irq, NULL);
> - }
> - }
> -
> - min += cluster_size;
> -
> - if (min > map->max_apic_id)
> - goto out;
> -
> - for_each_set_bit(i, &ipi_bitmap_high,
> - min((u32)BITS_PER_LONG, (map->max_apic_id - min + 1))) {
> - if (map->phys_map[min + i]) {
> - vcpu = map->phys_map[min + i]->vcpu;
> - count += kvm_apic_set_irq(vcpu, &irq, NULL);
> - }
> - }
> -
> -out:
> rcu_read_unlock();
> return count;
> }
>

Queued, thanks.

Paolo