On Mon, Nov 04, 2024 at 04:57:06PM +0800, Philo Lu wrote:
> RSS configuration should be updated with queue number. In particular, it
> should be updated when (1) rss enabled and (2) default rss configuration
> is used without user modification.
>
> During rss command processing, device updates queue_pairs using
> rss.max_tx_vq. That is, the device updates queue_pairs together with
> rss, so we can skip the sperate queue_pairs update
> (VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET below) and return directly.
>
> Also remove the `vi->has_rss ?` check when setting vi->rss.max_tx_vq,
> because this is not used in the other hash_report case.
>
> Fixes: c7114b1249fa ("drivers/net/virtio_net: Added basic RSS support.")
> Signed-off-by: Philo Lu <lulie@xxxxxxxxxxxxxxxxx>
> Signed-off-by: Xuan Zhuo <xuanzhuo@xxxxxxxxxxxxxxxxx>
> ---
> drivers/net/virtio_net.c | 65 +++++++++++++++++++++++++++++++---------
> 1 file changed, 51 insertions(+), 14 deletions(-)
>
> diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
> index 59d9fdf562e0..189afad3ffaa 100644
> --- a/drivers/net/virtio_net.c
> +++ b/drivers/net/virtio_net.c
> @@ -3394,15 +3394,59 @@ static void virtnet_ack_link_announce(struct virtnet_info *vi)
> dev_warn(&vi->dev->dev, "Failed to ack link announce.\n");
> }
>
> +static bool virtnet_commit_rss_command(struct virtnet_info *vi);
> +
> +static void virtnet_rss_update_by_qpairs(struct virtnet_info *vi, u16 queue_pairs)
> +{
> + u32 indir_val = 0;
> + int i = 0;
> +
> + for (; i < vi->rss_indir_table_size; ++i) {
> + indir_val = ethtool_rxfh_indir_default(i, queue_pairs);
> + vi->rss.indirection_table[i] = indir_val;
> + }
> + vi->rss.max_tx_vq = queue_pairs;
> +}
> +
> static int virtnet_set_queues(struct virtnet_info *vi, u16 queue_pairs)
> {
> struct virtio_net_ctrl_mq *mq __free(kfree) = NULL;
> - struct scatterlist sg;
> + struct virtio_net_ctrl_rss old_rss;
> struct net_device *dev = vi->dev;
> + struct scatterlist sg;
>
> if (!vi->has_cvq || !virtio_has_feature(vi->vdev, VIRTIO_NET_F_MQ))
> return 0;
>
> + /* Firstly check if we need update rss. Do updating if both (1) rss enabled and
> + * (2) no user configuration.
> + *
> + * During rss command processing, device updates queue_pairs using rss.max_tx_vq. That is,
> + * the device updates queue_pairs together with rss, so we can skip the sperate queue_pairs
> + * update (VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET below) and return directly.
> + */
> + if (vi->has_rss && !netif_is_rxfh_configured(dev)) {
Does there need to be an error case when:
vi->has_rss && netif_is_rxfh_configured(dev)
to return EINVAL? I noted that other drivers don't let users adjust
the queue count and return error in this case.
> + memcpy(&old_rss, &vi->rss, sizeof(old_rss));
> + if (rss_indirection_table_alloc(&vi->rss, vi->rss_indir_table_size)) {
> + vi->rss.indirection_table = old_rss.indirection_table;
> + return -ENOMEM;
> + }
> +
> + virtnet_rss_update_by_qpairs(vi, queue_pairs);
> +
> + if (!virtnet_commit_rss_command(vi)) {
> + /* restore ctrl_rss if commit_rss_command failed */
> + rss_indirection_table_free(&vi->rss);
> + memcpy(&vi->rss, &old_rss, sizeof(old_rss));
> +
> + dev_warn(&dev->dev, "Fail to set num of queue pairs to %d, because committing RSS failed\n",
> + queue_pairs);
> + return -EINVAL;
> + }
> + rss_indirection_table_free(&old_rss);
> + goto succ;
> + }
> +
