On Wed, Aug 12, 2009 at 11:09:58AM +0300, Avi Kivity wrote:
> On 08/11/2009 03:31 PM, Gleb Natapov wrote:
>> Maintain back mapping from irqchip/pin to gsi to speedup
>> interrupt acknowledgment notifications.
>>
>> Signed-off-by: Gleb Natapov<gleb@xxxxxxxxxx>
>> ---
>> include/linux/kvm_host.h | 1 +
>> virt/kvm/irq_comm.c | 24 +++++++++++-------------
>> 2 files changed, 12 insertions(+), 13 deletions(-)
>>
>> diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
>> index 09df31d..d2b8eb3 100644
>> --- a/include/linux/kvm_host.h
>> +++ b/include/linux/kvm_host.h
>> @@ -133,6 +133,7 @@ struct kvm_kernel_irq_routing_entry {
>> };
>>
>> struct kvm_irq_routing_table {
>> + int chip[3][KVM_IOAPIC_NUM_PINS];
>>
>
> KVM_NR_IRQCHIPS
>
> An alternative implementation is to embed a lookup table in each
> irqchip. I don't think it's really necessary.
>
>> --- a/virt/kvm/irq_comm.c
>> +++ b/virt/kvm/irq_comm.c
>> @@ -168,21 +168,13 @@ void kvm_notify_acked_irq(struct kvm *kvm, unsigned irqchip, unsigned pin)
>> {
>> struct kvm_irq_ack_notifier *kian;
>> struct hlist_node *n;
>> - unsigned gsi = pin;
>> - int i;
>> + unsigned gsi;
>>
>> trace_kvm_ack_irq(irqchip, pin);
>>
>> - for (i = 0; i< kvm->irq_routing->nr_rt_entries; i++) {
>> - struct kvm_kernel_irq_routing_entry *e;
>> - e =&kvm->irq_routing->rt_entries[i];
>> - if (e->type == KVM_IRQ_ROUTING_IRQCHIP&&
>> - e->irqchip.irqchip == irqchip&&
>> - e->irqchip.pin == pin) {
>> - gsi = e->gsi;
>> - break;
>> - }
>> - }
>> + gsi = kvm->irq_routing->chip[irqchip][pin];
>> + if (gsi == -1)
>> + gsi = pin;
>>
>
> What's this?
>
If there is not GSI mapping use pin as gsi. This what current code does.
We can BUG() here I think.
--
Gleb.
--
To unsubscribe from this list: send the line "unsubscribe kvm" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
