Re: [RFC PATCH 1/2] KVM: count the number of dirty bits for each memslot

[Avi Kivity <avi@redhat.com>]

On 11/18/2010 07:14 AM, Takuya Yoshikawa wrote:
> This patch introduces the counter to hold the number of dirty bits in each
> memslot. We will use this to optimize dirty logging later.
>
>
> @@ -3217,11 +3216,8 @@ int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm,
>
>   	n = kvm_dirty_bitmap_bytes(memslot);
>
> -	for (i = 0; !is_dirty&&  i<  n/sizeof(long); i++)
> -		is_dirty = memslot->dirty_bitmap[i];
> -

This can already be an improvement.
> @@ -152,6 +152,7 @@ struct kvm_memory_slot {
>   	unsigned long *rmap;
>   	unsigned long *dirty_bitmap;
>   	unsigned long *dirty_bitmap_head;
> +	unsigned long num_dirty_bits;

The bits themselves are not dirty; only the pages are dirty.

(+ we usually use 'nr' for 'number')



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