Re: [Qemu-devel] [PATCH 2/3] net: Flush queues when runstate changes back to running

[zhanghailiang <zhang.zhanghailiang@huawei.com>]

On 2014/8/14 18:09, Michael S. Tsirkin wrote:
> On Thu, Aug 14, 2014 at 02:13:57PM +0800, zhanghailiang wrote:
>> When the runstate changes back to running, we definitely need to flush
>> queues to get packets flowing again.
>>
>> Here we implement this in the net layer:
>> (1) add a member 'VMChangeStateEntry *vmstate' to struct NICState,
>> Which will listen for VM runstate changes.
>> (2) Register a handler function for VMstate change.
>> When vm changes back to running, we flush all queues in the callback function.
>>
>> Signed-off-by: zhanghailiang<zhang.zhanghailiang@huawei.com>
>
> Hmm looks like virtio patch will need to be squashed as well?
>

OK, thanks.

>> ---
>>   include/net/net.h |  1 +
>>   net/net.c         | 26 ++++++++++++++++++++++++++
>>   2 files changed, 27 insertions(+)
>>
>> diff --git a/include/net/net.h b/include/net/net.h
>> index 312f728..a294277 100644
>> --- a/include/net/net.h
>> +++ b/include/net/net.h
>> @@ -97,6 +97,7 @@ typedef struct NICState {
>>       NICConf *conf;
>>       void *opaque;
>>       bool peer_deleted;
>> +    VMChangeStateEntry *vmstate;
>>   } NICState;
>>
>>   NetClientState *qemu_find_netdev(const char *id);
>> diff --git a/net/net.c b/net/net.c
>> index 5bb2821..506e58f 100644
>> --- a/net/net.c
>> +++ b/net/net.c
>> @@ -242,6 +242,29 @@ NetClientState *qemu_new_net_client(NetClientInfo *info,
>>       return nc;
>>   }
>>
>> +static void nic_vmstate_change_handler(void *opaque,
>> +                                       int running,
>> +                                       RunState state)
>> +{
>> +    NICState *nic = opaque;
>> +    NetClientState *nc;
>> +    int i, queues;
>> +
>> +    if (!running) {
>> +        return;
>> +    }
>> +
>> +    queues =  MAX(1, nic->conf->peers.queues);
>> +    for (i = 0; i<  queues; i++) {
>> +        nc =&nic->ncs[i];
>> +        if (nc->receive_disabled
>> +            || (nc->info->can_receive&&  !nc->info->can_receive(nc))) {
>> +            continue;
>> +        }
>> +        qemu_flush_queued_packets(nc);
>> +    }
>> +}
>> +
>>   NICState *qemu_new_nic(NetClientInfo *info,
>>                          NICConf *conf,
>>                          const char *model,
>> @@ -259,6 +282,8 @@ NICState *qemu_new_nic(NetClientInfo *info,
>>       nic->ncs = (void *)nic + info->size;
>>       nic->conf = conf;
>>       nic->opaque = opaque;
>> +    nic->vmstate = qemu_add_vm_change_state_handler(nic_vmstate_change_handler,
>> +                                                    nic);
>>
>>       for (i = 0; i<  queues; i++) {
>>           qemu_net_client_setup(&nic->ncs[i], info, peers[i], model, name,
>> @@ -379,6 +404,7 @@ void qemu_del_nic(NICState *nic)
>>           qemu_free_net_client(nc);
>>       }
>>
>> +    qemu_del_vm_change_state_handler(nic->vmstate);
>>       g_free(nic);
>>   }
>>
>> --
>> 1.7.12.4
>>
>
> .
>