Re: [PATCH RFC] kvm: fast-path msi injection with irqfd

[Avi Kivity <avi@redhat.com>]

On 11/18/2010 01:10 PM, Michael S. Tsirkin wrote:
> >  I guess I should create an empty Documentation/kvm/locking.txt and
> >  force everyone else to update it.
>
> Comments near the relevant fields not better?
>

Not an either/or.  You can't understand the system from random source 
comments.

> diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
> index a055742..d13ced3 100644
> --- a/include/linux/kvm_host.h
> +++ b/include/linux/kvm_host.h
> @@ -16,6 +16,7 @@
>   #include<linux/mm.h>
>   #include<linux/preempt.h>
>   #include<linux/msi.h>
> +#include<linux/rcupdate.h>
>   #include<asm/signal.h>
>
>   #include<linux/kvm.h>
> @@ -206,6 +207,8 @@ struct kvm {
>
>   	struct mutex irq_lock;
>   #ifdef CONFIG_HAVE_KVM_IRQCHIP
> +	/* Update side is protected by irq_lock and,
> +	 * if configured, irqfds.lock. */

/*
  * kernel style comment
  * here and elsewhere
  */



>   	struct kvm_irq_routing_table __rcu *irq_routing;
>   	struct hlist_head mask_notifier_list;
>   	struct hlist_head irq_ack_notifier_list;
> @@ -462,6 +465,8 @@ void kvm_get_intr_delivery_bitmask(struct kvm_ioapic *ioapic,
>   				   unsigned long *deliver_bitmask);
>   #endif
>   int kvm_set_irq(struct kvm *kvm, int irq_source_id, u32 irq, int level);
> +int kvm_set_msi(struct kvm_kernel_irq_routing_entry *irq_entry, struct kvm *kvm,
> +		int irq_source_id, int level);

No point in the level argument for an msi specific function.

>
>   #else
> @@ -614,6 +620,12 @@ static inline int kvm_irqfd(struct kvm *kvm, int fd, int gsi, int flags)
>   }
>
>   static inline void kvm_irqfd_release(struct kvm *kvm) {}

blank line

> +static inline void kvm_irq_routing_update(struct kvm *kvm,
> +					  struct kvm_irq_routing_table *irq_rt)
> +{
> +	rcu_assign_pointer(kvm->irq_routing, irq_rt);
> +}
> +
>   static inline int kvm_ioeventfd(struct kvm *kvm, struct kvm_ioeventfd *args)
>   {
>   	return -ENOSYS;

Apart from these minor issues, looks good.

-- 
error compiling committee.c: too many arguments to function