Re: [Qemu-devel] [PATCH 2/4] net/colo-compare.c: compare tcp packet base on sequence number

[Li Zhijian]

this title confused me

i think you want to express "only compare the packets that has the same sequence 
number"

and i think this optimization can not reduce this checkpoint optimization.

Thanks


On 07/07/2017 01:43 PM, Zhang Chen wrote:
> If primary packet's sequence number not same with secondary packet's
> sequence number, no need to compare the packet other field.
>
> Signed-off-by: Zhang Chen <address@hidden>
> ---
>   net/colo-compare.c | 6 ++++++
>   1 file changed, 6 insertions(+)
>
> diff --git a/net/colo-compare.c b/net/colo-compare.c
> index 0f8e198..2caeb80 100644
> --- a/net/colo-compare.c
> +++ b/net/colo-compare.c
> @@ -222,6 +222,12 @@ static int colo_packet_compare_tcp(Packet *spkt, Packet 
> *ppkt)
>       ptcp = (struct tcphdr *)ppkt->transport_header;
>       stcp = (struct tcphdr *)spkt->transport_header;
>   
> +    if ((ptcp->th_flags & TH_SYN) != TH_SYN &&
> +        ptcp->th_seq != stcp->th_seq) {
> +        trace_colo_compare_main("colo_packet_compare_tcp seq not same");
> +        return -1;
> +    }
> +
>       /*
>        * The 'identification' field in the IP header is *very* random
>        * it almost never matches.  Fudge this by ignoring differences in