Re: [PATCH net-next v2 4/6] virtio_net: Do DIM update for specified queue only

[Heng Qi <hengqi@xxxxxxxxxxxxxxxxx>]

在 2024/3/28 下午12:47, Daniel Jurgens 写道:
> Since we no longer have to hold the RTNL lock here just do updates for
> the specified queue.
>
> Signed-off-by: Daniel Jurgens <danielj@xxxxxxxxxx>
> ---
>   drivers/net/virtio_net.c | 38 ++++++++++++++------------------------
>   1 file changed, 14 insertions(+), 24 deletions(-)
>
> diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
> index b9298544b1b5..9c4bfb1eb15c 100644
> --- a/drivers/net/virtio_net.c
> +++ b/drivers/net/virtio_net.c
> @@ -3596,36 +3596,26 @@ static void virtnet_rx_dim_work(struct work_struct *work)
>   	struct virtnet_info *vi = rq->vq->vdev->priv;
>   	struct net_device *dev = vi->dev;
>   	struct dim_cq_moder update_moder;
> -	int i, qnum, err;
> +	int qnum, err;
>   
>   	if (!rtnl_trylock())
>   		return;
>   
> -	/* Each rxq's work is queued by "net_dim()->schedule_work()"
> -	 * in response to NAPI traffic changes. Note that dim->profile_ix
> -	 * for each rxq is updated prior to the queuing action.
> -	 * So we only need to traverse and update profiles for all rxqs
> -	 * in the work which is holding rtnl_lock.
> -	 */
> -	for (i = 0; i < vi->curr_queue_pairs; i++) {
> -		rq = &vi->rq[i];
> -		dim = &rq->dim;
> -		qnum = rq - vi->rq;
> +	qnum = rq - vi->rq;
>   
> -		if (!rq->dim_enabled)
> -			continue;
> +	if (!rq->dim_enabled)
> +		continue;

?

continue what?

For the lock code, please pass the test. It's important.

Regards,
Heng

>   
> -		update_moder = net_dim_get_rx_moderation(dim->mode, dim->profile_ix);
> -		if (update_moder.usec != rq->intr_coal.max_usecs ||
> -		    update_moder.pkts != rq->intr_coal.max_packets) {
> -			err = virtnet_send_rx_ctrl_coal_vq_cmd(vi, qnum,
> -							       update_moder.usec,
> -							       update_moder.pkts);
> -			if (err)
> -				pr_debug("%s: Failed to send dim parameters on rxq%d\n",
> -					 dev->name, qnum);
> -			dim->state = DIM_START_MEASURE;
> -		}
> +	update_moder = net_dim_get_rx_moderation(dim->mode, dim->profile_ix);
> +	if (update_moder.usec != rq->intr_coal.max_usecs ||
> +	    update_moder.pkts != rq->intr_coal.max_packets) {
> +		err = virtnet_send_rx_ctrl_coal_vq_cmd(vi, qnum,
> +						       update_moder.usec,
> +						       update_moder.pkts);
> +		if (err)
> +			pr_debug("%s: Failed to send dim parameters on rxq%d\n",
> +				 dev->name, qnum);
> +		dim->state = DIM_START_MEASURE;
>   	}
>   
>   	rtnl_unlock();