Re: [Qemu-devel] [PATCH 3/8] Sort RAMBlocks by ID for migration, not by ram_addr

[Anthony Liguori <anthony@codemonkey.ws>]

On 12/21/2011 07:34 AM, Avi Kivity wrote:
> ram_addr is (a) unstable (b) going away.  Sort by idstr instead.
>
> Signed-off-by: Avi Kivity<avi@redhat.com>

I don't see this as a problem, per say, but this is a significant behavioral 
change.  ram_addr does correspond roughly to the location in memory and 
historically we would send memory starting from 0 upward whereas now, the order 
that we send RAMBlocks will be random for all intents and purposes.

Again, I don't think it's a problem, but we should note this in the commit 
message in case it creates a problem down the road.

Regards,

Anthony Liguori

> ---
>   arch_init.c |    8 ++------
>   1 files changed, 2 insertions(+), 6 deletions(-)
>
> diff --git a/arch_init.c b/arch_init.c
> index 2743bfd..8a3f052 100644
> --- a/arch_init.c
> +++ b/arch_init.c
> @@ -217,12 +217,8 @@ static int block_compar(const void *a, const void *b)
>   {
>       RAMBlock * const *ablock = a;
>       RAMBlock * const *bblock = b;
> -    if ((*ablock)->offset<  (*bblock)->offset) {
> -        return -1;
> -    } else if ((*ablock)->offset>  (*bblock)->offset) {
> -        return 1;
> -    }
> -    return 0;
> +
> +    return strcmp((*ablock)->idstr, (*bblock)->idstr);
>   }
>
>   static void sort_ram_list(void)