Subject: Re: [RFC V7 PATCH 7/7] vhost_net: add interrupt coalescing support

From: Jason Wang <[email-masked]>
Date: Wed, 27 May 2015 16:30:48 +0800

On 05/27/2015 02:02 AM, Stephen Hemminger wrote:
> On Mon, 25 May 2015 01:24:04 -0400
> Jason Wang <[email-masked]> wrote:
>
>> Signed-off-by: Jason Wang <[email-masked]>
>> ---
>>  drivers/vhost/net.c | 8 ++++++++
>>  1 file changed, 8 insertions(+)
>>
>> diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c
>> index 7d137a4..5ee28b7 100644
>> --- a/drivers/vhost/net.c
>> +++ b/drivers/vhost/net.c
>> @@ -320,6 +320,9 @@ static void handle_tx(struct vhost_net *net)
>>  	hdr_size = nvq->vhost_hlen;
>>  	zcopy = nvq->ubufs;
>>  
>> +	/* Finish pending interrupts first */
>> +	vhost_check_coalesce_and_signal(vq->dev, vq, false);
>> +
>>  	for (;;) {
>>  		/* Release DMAs done buffers first */
>>  		if (zcopy)
>> @@ -415,6 +418,7 @@ static void handle_tx(struct vhost_net *net)
>>  		}
>>  	}
>>  out:
>> +	vhost_check_coalesce_and_signal(vq->dev, vq, true);
>>  	mutex_unlock(&vq->mutex);
>>  }
>>  
>> @@ -554,6 +558,9 @@ static void handle_rx(struct vhost_net *net)
>>  		vq->log : NULL;
>>  	mergeable = vhost_has_feature(vq, VIRTIO_NET_F_MRG_RXBUF);
>>  
>> +	/* Finish pending interrupts first */
>> +	vhost_check_coalesce_and_signal(vq->dev, vq, false);
>> +
>>  	while ((sock_len = peek_head_len(sock->sk))) {
>>  		sock_len += sock_hlen;
>>  		vhost_len = sock_len + vhost_hlen;
>> @@ -638,6 +645,7 @@ static void handle_rx(struct vhost_net *net)
>>  		}
>>  	}
>>  out:
>> +	vhost_check_coalesce_and_signal(vq->dev, vq, true);
>>  	mutex_unlock(&vq->mutex);
>>  }
>>  
> Could you implement ethtool control of these coalescing parameters?

I believe you mean guest ethtool control. If yes, it has been
implemented in [RFC V7 PATCH 4/7] virtio-net: add basic interrupt
coalescing support.