Re: [Qemu-devel] [RFC PATCH V3 3/4] colo-compare: introduce packet comparison thread

[Jason Wang]

On 04/28/2016 06:31 PM, Zhang Chen wrote:
>>> +/*
>>> + * called from the compare thread on the primary
>>> + * for compare connection
>>> + */
>>> +static void colo_compare_connection(void *opaque, void *user_data)
>>> +{
>>> +    Connection *conn = opaque;
>>> +    Packet *pkt = NULL;
>>> +    GList *result = NULL;
>>> +    int ret;
>>> +
>>> +    qemu_mutex_lock(&conn->list_lock);
>>> +    while (!g_queue_is_empty(&conn->primary_list) &&
>>> +           !g_queue_is_empty(&conn->secondary_list)) {
>>> +        pkt = g_queue_pop_head(&conn->primary_list);
>>> +        result = g_queue_find_custom(&conn->secondary_list,
>>> +                              pkt,
>>> (GCompareFunc)colo_packet_compare_all);
>>> +
>>> +        if (result) {
>>> +            ret = compare_chr_send(pkt->s->chr_out, pkt->data,
>>> pkt->size);
>>> +            if (ret < 0) {
>>> +                error_report("colo_send_primary_packet failed");
>>> +            }
>>> +            trace_colo_compare_main("packet same and release packet");
>>> +            g_queue_remove(&conn->secondary_list, result->data);
>>> +        } else {
>>> +            trace_colo_compare_main("packet different");
>>> +            g_queue_push_head(&conn->primary_list, pkt);
>> Is this possible that the packet from secondary has not been arrived on
>> time? If yes, do we still need to notify the checkpoint here?
>
> Yes,the packet of secondary may not arrived.
> we will hold primary packet to next periodic checkpoint
> to flush it. and more, I consider to set a timer
> to flush timeout(200ms???) packet like Dave's branch.
>
>
> Thanks
> zhangchen 

I was wondering maybe you can merge or unify all other changes from
Dave's branch?