Re: [PATCH net-next V4 2/3] virtio_net: support per queue interrupt coalesce command

[Jason Wang <jasowang@redhat.com>]

在 2023/7/28 13:46, Michael S. Tsirkin 写道:
> On Thu, Jul 27, 2023 at 03:28:32PM +0200, Paolo Abeni wrote:
>> On Tue, 2023-07-25 at 16:07 +0300, Gavin Li wrote:
>>> Add interrupt_coalesce config in send_queue and receive_queue to cache user
>>> config.
>>>
>>> Send per virtqueue interrupt moderation config to underlying device in
>>> order to have more efficient interrupt moderation and cpu utilization of
>>> guest VM.
>>>
>>> Additionally, address all the VQs when updating the global configuration,
>>> as now the individual VQs configuration can diverge from the global
>>> configuration.
>>>
>>> Signed-off-by: Gavin Li <gavinl@nvidia.com>
>>> Reviewed-by: Dragos Tatulea <dtatulea@nvidia.com>
>>> Reviewed-by: Jiri Pirko <jiri@nvidia.com>
>>> Acked-by: Michael S. Tsirkin <mst@redhat.com>
>> FTR, this patch is significantly different from the version previously
>> acked/reviewed, I'm unsure if all the reviewers are ok with the new
>> one.
>>
>> [...]
> still ok by me
>
> Acked-by: Michael S. Tsirkin <mst@redhat.com>
>
> let's wait for Jason too.


I'm fine with this series (I've acked each patch).

Thanks


>
>>>   static int virtnet_set_coalesce(struct net_device *dev,
>>>   				struct ethtool_coalesce *ec,
>>>   				struct kernel_ethtool_coalesce *kernel_coal,
>>>   				struct netlink_ext_ack *extack)
>>>   {
>>>   	struct virtnet_info *vi = netdev_priv(dev);
>>> -	int ret, i, napi_weight;
>>> +	int ret, queue_number, napi_weight;
>>>   	bool update_napi = false;
>>>   
>>>   	/* Can't change NAPI weight if the link is up */
>>>   	napi_weight = ec->tx_max_coalesced_frames ? NAPI_POLL_WEIGHT : 0;
>>> -	if (napi_weight ^ vi->sq[0].napi.weight) {
>>> -		if (dev->flags & IFF_UP)
>>> -			return -EBUSY;
>>> -		else
>>> -			update_napi = true;
>>> +	for (queue_number = 0; queue_number < vi->max_queue_pairs; queue_number++) {
>>> +		ret = virtnet_should_update_vq_weight(dev->flags, napi_weight,
>>> +						      vi->sq[queue_number].napi.weight,
>>> +						      &update_napi);
>>> +		if (ret)
>>> +			return ret;
>>> +
>>> +		if (update_napi) {
>>> +			/* All queues that belong to [queue_number, queue_count] will be
>>> +			 * updated for the sake of simplicity, which might not be necessary
>> It looks like the comment above still refers to the old code. Should
>> be:
>> 	[queue_number, vi->max_queue_pairs]
>> 			
>> Otherwise LGTM, thanks!
>>
>> Paolo