Re: [PATCH] vhost: notify guest to fill buffer when there is no buffer

[Linhaifeng <haifeng.lin-hv44wF8Li93QT0dZR+AlfA@public.gmane.org>]

On 2015/1/29 18:39, Xie, Huawei wrote:

>> -		if (count == 0)
>> +		/* If there is no buffers we should notify guest to fill.
>> +		* This is need when guest use virtio_net driver(not pmd).
>> +		*/
>> +		if (count == 0) {
>> +			if (!(vq->avail->flags &
>> VRING_AVAIL_F_NO_INTERRUPT))
>> +				eventfd_write((int)vq->kickfd, 1);
>>  			return 0;
>> +		}
> 
> Haifeng:
> Is it the root cause and is it protocol required?
> Could you give a detailed description for that scenario?
> 

I use mz to send data from one VM1 to VM2.The two VM use virtio-net driver.
VM1 execute follow script:
for((i=0;i<999999999;i++));
do
mz eth0 -t udp -A 1.1.1.1 -B 1.1.1.2 -a 00:00:00:00:00:01 -b 00:00:00:00:00:02 -c 10000000 -p 512
sleep 4
done

VM2 execute follow command to watch:
watch -d ifconfig

After many hours VM2 stop to receive data.

Could you test it ?
-- 
Regards,
Haifeng