Hi Maxime,
> -----Original Message-----
> From: Maxime Coquelin <maxime.coque...@redhat.com>
> Sent: Monday, October 4, 2021 10:30 PM
> To: dev@dpdk.org; Xia, Chenbo <chenbo....@intel.com>; amore...@redhat.com;
> david.march...@redhat.com; andrew.rybche...@oktetlabs.ru; Yigit, Ferruh
> <ferruh.yi...@intel.com>; michae...@nvidia.com; viachesl...@nvidia.com; Li,
> Xiaoyun <xiaoyun...@intel.com>
> Cc: nelio.laranje...@6wind.com; yvuge...@redhat.com; ybend...@redhat.com;
> Maxime Coquelin <maxime.coque...@redhat.com>
> Subject: [PATCH v4 1/5] net/virtio: add initial RSS support
>
> Provide the capability to update the hash key, hash types
> and RETA table on the fly (without needing to stop/start
> the device). However, the key length and the number of RETA
> entries are fixed to 40B and 128 entries respectively. This
> is done in order to simplify the design, but may be
> revisited later as the Virtio spec provides this
> flexibility.
>
> Note that only VIRTIO_NET_F_RSS support is implemented,
> VIRTIO_NET_F_HASH_REPORT, which would enable reporting the
> packet RSS hash calculated by the device into mbuf.rss, is
> not yet supported.
>
> Regarding the default RSS configuration, it has been
> chosen to use the default Intel ixgbe key as default key,
> and default RETA is a simple modulo between the hash and
> the number of Rx queues.
>
> Signed-off-by: Maxime Coquelin <maxime.coque...@redhat.com>
> ---
[...]
> +static int
> +virtio_dev_get_rss_config(struct virtio_hw *hw, uint32_t *rss_hash_types)
> +{
> + struct virtio_net_config local_config;
> + struct virtio_net_config *config = &local_config;
> +
> + virtio_read_dev_config(hw,
> + offsetof(struct virtio_net_config, rss_max_key_size),
> + &config->rss_max_key_size,
> + sizeof(config->rss_max_key_size));
> + if (config->rss_max_key_size < VIRTIO_NET_RSS_KEY_SIZE) {
> + PMD_INIT_LOG(ERR, "Invalid device RSS max key size (%u)",
> + config->rss_max_key_size);
> + return -EINVAL;
> + }
> +
> + virtio_read_dev_config(hw,
> + offsetof(struct virtio_net_config,
> + rss_max_indirection_table_length),
> + &config->rss_max_indirection_table_length,
> + sizeof(config->rss_max_indirection_table_length));
> + if (config->rss_max_indirection_table_length < VIRTIO_NET_RSS_RETA_SIZE)
> {
> + PMD_INIT_LOG(ERR, "Invalid device RSS max reta size (%u)",
> + config->rss_max_indirection_table_length);
> + return -EINVAL;
> + }
> +
> + virtio_read_dev_config(hw,
> + offsetof(struct virtio_net_config,
> supported_hash_types),
> + &config->supported_hash_types,
> + sizeof(config->supported_hash_types));
> + if ((config->supported_hash_types & VIRTIO_NET_HASH_TYPE_MASK) == 0) {
> + PMD_INIT_LOG(ERR, "Invalid device RSS hash types (%u)",
Better use 0x%x to be more user friendly
> + config->supported_hash_types);
> + return -EINVAL;
> + }
> +
> + *rss_hash_types = config->supported_hash_types &
> VIRTIO_NET_HASH_TYPE_MASK;
> +
> + PMD_INIT_LOG(DEBUG, "Device RSS config:");
> + PMD_INIT_LOG(DEBUG, "\t-Max key size: %u", config->rss_max_key_size);
> + PMD_INIT_LOG(DEBUG, "\t-Max reta size: %u", config-
> >rss_max_indirection_table_length);
> + PMD_INIT_LOG(DEBUG, "\t-Supported hash types: 0x%x", *rss_hash_types);
> +
> + return 0;
> +}
> +
> +static int
> +virtio_dev_rss_hash_update(struct rte_eth_dev *dev,
> + struct rte_eth_rss_conf *rss_conf)
> +{
> + struct virtio_hw *hw = dev->data->dev_private;
> + uint16_t nb_queues;
> +
> + if (!virtio_with_feature(hw, VIRTIO_NET_F_RSS))
> + return -ENOTSUP;
> +
> + if (rss_conf->rss_hf &
> ~virtio_to_ethdev_rss_offloads(VIRTIO_NET_HASH_TYPE_MASK))
> + return -EINVAL;
> +
> + hw->rss_hash_types = ethdev_to_virtio_rss_offloads(rss_conf->rss_hf);
> +
> + if (rss_conf->rss_key && rss_conf->rss_key_len) {
> + if (rss_conf->rss_key_len != VIRTIO_NET_RSS_KEY_SIZE) {
> + PMD_INIT_LOG(ERR, "Driver only supports %u RSS key
> length",
> + VIRTIO_NET_RSS_KEY_SIZE);
> + return -EINVAL;
> + }
> + memcpy(hw->rss_key, rss_conf->rss_key, VIRTIO_NET_RSS_KEY_SIZE);
> + }
> +
> + nb_queues = RTE_MAX(dev->data->nb_rx_queues, dev->data->nb_tx_queues);
> + return virtio_set_multiple_queues_rss(dev, nb_queues);
> +}
> +
> +static int
> +virtio_dev_rss_hash_conf_get(struct rte_eth_dev *dev,
> + struct rte_eth_rss_conf *rss_conf)
> +{
> + struct virtio_hw *hw = dev->data->dev_private;
> +
> + if (!virtio_with_feature(hw, VIRTIO_NET_F_RSS))
> + return -ENOTSUP;
> +
> + if (rss_conf->rss_key && rss_conf->rss_key_len >=
> VIRTIO_NET_RSS_KEY_SIZE)
> + memcpy(rss_conf->rss_key, hw->rss_key, VIRTIO_NET_RSS_KEY_SIZE);
> + rss_conf->rss_key_len = VIRTIO_NET_RSS_KEY_SIZE;
> + rss_conf->rss_hf = virtio_to_ethdev_rss_offloads(hw->rss_hash_types);
> +
> + return 0;
> +}
> +
> +static int virtio_dev_rss_reta_update(struct rte_eth_dev *dev,
> + struct rte_eth_rss_reta_entry64 *reta_conf,
> + uint16_t reta_size)
> +{
> + struct virtio_hw *hw = dev->data->dev_private;
> + uint16_t nb_queues;
> + int idx, pos, i;
> +
> + if (!virtio_with_feature(hw, VIRTIO_NET_F_RSS))
> + return -ENOTSUP;
> +
> + if (reta_size != VIRTIO_NET_RSS_RETA_SIZE)
> + return -EINVAL;
> +
> + for (idx = 0, i = 0; i < reta_size; i++) {
idx is calculated every time. No need to do 'idx = 0'.
> + idx = i / RTE_RETA_GROUP_SIZE;
> + pos = i % RTE_RETA_GROUP_SIZE;
> +
> + if (((reta_conf[idx].mask >> pos) & 0x1) == 0)
> + continue;
> +
> + hw->rss_reta[i] = reta_conf[idx].reta[pos];
> + }
> +
> + nb_queues = RTE_MAX(dev->data->nb_rx_queues, dev->data->nb_tx_queues);
> + return virtio_set_multiple_queues_rss(dev, nb_queues);
> +}
> +
> +static int virtio_dev_rss_reta_query(struct rte_eth_dev *dev,
> + struct rte_eth_rss_reta_entry64 *reta_conf,
> + uint16_t reta_size)
> +{
> + struct virtio_hw *hw = dev->data->dev_private;
> + int idx, i;
> +
> + if (!virtio_with_feature(hw, VIRTIO_NET_F_RSS))
> + return -ENOTSUP;
> +
> + if (reta_size != VIRTIO_NET_RSS_RETA_SIZE)
> + return -EINVAL;
> +
> + for (idx = 0, i = 0; i < reta_size; i++) {
Ditto
> + idx = i / RTE_RETA_GROUP_SIZE;
> + reta_conf[idx].reta[i % RTE_RETA_GROUP_SIZE] = hw->rss_reta[i];
> + }
> +
> + return 0;
> +}
> +
> +/*
[...]
> +/**
> + * RSS control
> + *
> + * The RSS feature <todo>
> + */
> +#define VIRTIO_NET_RSS_RETA_SIZE 128
> +#define VIRTIO_NET_RSS_KEY_SIZE 40
Forgot to align the numbers? :)
Thanks,
Chenbo
> +
> +struct virtio_net_ctrl_rss {
> + uint32_t hash_types;
> + uint16_t indirection_table_mask;
> + uint16_t unclassified_queue;
> + uint16_t indirection_table[VIRTIO_NET_RSS_RETA_SIZE];
> + uint16_t max_tx_vq;
> + uint8_t hash_key_length;
> + uint8_t hash_key_data[VIRTIO_NET_RSS_KEY_SIZE];
> +};
> +
> /*
> * Control link announce acknowledgement
> *
> @@ -292,7 +310,10 @@ struct virtqueue {
>
> /* If multiqueue is provided by host, then we suppport it. */
> #define VIRTIO_NET_CTRL_MQ 4
> +
> #define VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET 0
> +#define VIRTIO_NET_CTRL_MQ_RSS_CONFIG 1
> +
> #define VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MIN 1
> #define VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MAX 0x8000
>
> --
> 2.31.1
