[dpdk-dev] [PATCH v3 1/9] ethdev: introduce Rx buffer split

[Andrew Rybchenko]

On 10/12/20 8:03 PM, Thomas Monjalon wrote:
> 12/10/2020 18:38, Andrew Rybchenko:
>> On 10/12/20 7:19 PM, Viacheslav Ovsiienko wrote:
>>>  int
>>> +rte_eth_rxseg_queue_setup(uint16_t port_id, uint16_t rx_queue_id,
>>> +			  uint16_t nb_rx_desc, unsigned int socket_id,
>>> +			  const struct rte_eth_rxconf *rx_conf,
>>> +			  const struct rte_eth_rxseg *rx_seg, uint16_t n_seg)
>>> +{
>>> +	int ret;
>>> +	uint16_t seg_idx;
>>> +	uint32_t mbp_buf_size;
>>
>> <start-of-dup>
>>
>>> +	struct rte_eth_dev *dev;
>>> +	struct rte_eth_dev_info dev_info;
>>> +	struct rte_eth_rxconf local_conf;
>>> +	void **rxq;
>>> +
>>> +	RTE_ETH_VALID_PORTID_OR_ERR_RET(port_id, -EINVAL);
>>> +
>>> +	dev = &rte_eth_devices[port_id];
>>> +	if (rx_queue_id >= dev->data->nb_rx_queues) {
>>> +		RTE_ETHDEV_LOG(ERR, "Invalid RX queue_id=%u\n", rx_queue_id);
>>> +		return -EINVAL;
>>> +	}
>>
>> <end-of-dup>
>>
>>> +
>>> +	if (rx_seg == NULL) {
>>> +		RTE_ETHDEV_LOG(ERR, "Invalid null description pointer\n");
>>> +		return -EINVAL;
>>> +	}
>>> +
>>> +	if (n_seg == 0) {
>>> +		RTE_ETHDEV_LOG(ERR, "Invalid zero description number\n");
>>> +		return -EINVAL;
>>> +	}
>>> +
>>> +	RTE_FUNC_PTR_OR_ERR_RET(*dev->dev_ops->rxseg_queue_setup, -ENOTSUP);
>>> +
>>
>> <start-of-dup>
>>
>>> +	/*
>>> +	 * Check the size of the mbuf data buffer.
>>> +	 * This value must be provided in the private data of the memory pool.
>>> +	 * First check that the memory pool has a valid private data.
>>> +	 */
>>> +	ret = rte_eth_dev_info_get(port_id, &dev_info);
>>> +	if (ret != 0)
>>> +		return ret;
>>
>> <end-of-dup>
>>
>>> +
>>> +	for (seg_idx = 0; seg_idx < n_seg; seg_idx++) {
>>> +		struct rte_mempool *mp = rx_seg[seg_idx].mp;
>>> +
>>> +		if (mp->private_data_size <
>>> +				sizeof(struct rte_pktmbuf_pool_private)) {
>>> +			RTE_ETHDEV_LOG(ERR, "%s private_data_size %d < %d\n",
>>> +				mp->name, (int)mp->private_data_size,
>>> +				(int)sizeof(struct rte_pktmbuf_pool_private));
>>> +			return -ENOSPC;
>>> +		}
>>> +
>>> +		mbp_buf_size = rte_pktmbuf_data_room_size(mp);
>>> +		if (mbp_buf_size < rx_seg[seg_idx].length +
>>> +				   rx_seg[seg_idx].offset +
>>> +				   (seg_idx ? 0 :
>>> +				    (uint32_t)RTE_PKTMBUF_HEADROOM)) {
>>> +			RTE_ETHDEV_LOG(ERR,
>>> +				"%s mbuf_data_room_size %d < %d"
>>> +				" (segment length=%d + segment offset=%d)\n",
>>> +				mp->name, (int)mbp_buf_size,
>>> +				(int)(rx_seg[seg_idx].length +
>>> +				      rx_seg[seg_idx].offset),
>>> +				(int)rx_seg[seg_idx].length,
>>> +				(int)rx_seg[seg_idx].offset);
>>> +			return -EINVAL;
>>> +		}
>>> +	}
>>> +
>>
>> <start-of-huge-dup>
>>
>>> +	/* Use default specified by driver, if nb_rx_desc is zero */
>>> +	if (nb_rx_desc == 0) {
>>> +		nb_rx_desc = dev_info.default_rxportconf.ring_size;
>>> +		/* If driver default is also zero, fall back on EAL default */
>>> +		if (nb_rx_desc == 0)
>>> +			nb_rx_desc = RTE_ETH_DEV_FALLBACK_RX_RINGSIZE;
>>> +	}
>>> +
>>> +	if (nb_rx_desc > dev_info.rx_desc_lim.nb_max ||
>>> +			nb_rx_desc < dev_info.rx_desc_lim.nb_min ||
>>> +			nb_rx_desc % dev_info.rx_desc_lim.nb_align != 0) {
>>> +
>>> +		RTE_ETHDEV_LOG(ERR,
>>> +			"Invalid value for nb_rx_desc(=%hu), should be: "
>>> +			"<= %hu, >= %hu, and a product of %hu\n",
>>> +			nb_rx_desc, dev_info.rx_desc_lim.nb_max,
>>> +			dev_info.rx_desc_lim.nb_min,
>>> +			dev_info.rx_desc_lim.nb_align);
>>> +		return -EINVAL;
>>> +	}
>>> +
>>> +	if (dev->data->dev_started &&
>>> +		!(dev_info.dev_capa &
>>> +			RTE_ETH_DEV_CAPA_RUNTIME_RX_QUEUE_SETUP))
>>> +		return -EBUSY;
>>> +
>>> +	if (dev->data->dev_started &&
>>> +		(dev->data->rx_queue_state[rx_queue_id] !=
>>> +			RTE_ETH_QUEUE_STATE_STOPPED))
>>> +		return -EBUSY;
>>> +
>>> +	rxq = dev->data->rx_queues;
>>> +	if (rxq[rx_queue_id]) {
>>> +		RTE_FUNC_PTR_OR_ERR_RET(*dev->dev_ops->rx_queue_release,
>>> +					-ENOTSUP);
>>> +		(*dev->dev_ops->rx_queue_release)(rxq[rx_queue_id]);
>>> +		rxq[rx_queue_id] = NULL;
>>> +	}
>>> +
>>> +	if (rx_conf == NULL)
>>> +		rx_conf = &dev_info.default_rxconf;
>>> +
>>> +	local_conf = *rx_conf;
>>> +
>>> +	/*
>>> +	 * If an offloading has already been enabled in
>>> +	 * rte_eth_dev_configure(), it has been enabled on all queues,
>>> +	 * so there is no need to enable it in this queue again.
>>> +	 * The local_conf.offloads input to underlying PMD only carries
>>> +	 * those offloadings which are only enabled on this queue and
>>> +	 * not enabled on all queues.
>>> +	 */
>>> +	local_conf.offloads &= ~dev->data->dev_conf.rxmode.offloads;
>>> +
>>> +	/*
>>> +	 * New added offloadings for this queue are those not enabled in
>>> +	 * rte_eth_dev_configure() and they must be per-queue type.
>>> +	 * A pure per-port offloading can't be enabled on a queue while
>>> +	 * disabled on another queue. A pure per-port offloading can't
>>> +	 * be enabled for any queue as new added one if it hasn't been
>>> +	 * enabled in rte_eth_dev_configure().
>>> +	 */
>>> +	if ((local_conf.offloads & dev_info.rx_queue_offload_capa) !=
>>> +	     local_conf.offloads) {
>>> +		RTE_ETHDEV_LOG(ERR,
>>> +			"Ethdev port_id=%d rx_queue_id=%d, new added offloads"
>>> +			" 0x%"PRIx64" must be within per-queue offload"
>>> +			" capabilities 0x%"PRIx64" in %s()\n",
>>> +			port_id, rx_queue_id, local_conf.offloads,
>>> +			dev_info.rx_queue_offload_capa,
>>> +			__func__);
>>> +		return -EINVAL;
>>> +	}
>>> +
>>> +	/*
>>> +	 * If LRO is enabled, check that the maximum aggregated packet
>>> +	 * size is supported by the configured device.
>>> +	 */
>>> +	if (local_conf.offloads & DEV_RX_OFFLOAD_TCP_LRO) {
>>> +		if (dev->data->dev_conf.rxmode.max_lro_pkt_size == 0)
>>> +			dev->data->dev_conf.rxmode.max_lro_pkt_size =
>>> +				dev->data->dev_conf.rxmode.max_rx_pkt_len;
>>> +		int ret = check_lro_pkt_size(port_id,
>>> +				dev->data->dev_conf.rxmode.max_lro_pkt_size,
>>> +				dev->data->dev_conf.rxmode.max_rx_pkt_len,
>>> +				dev_info.max_lro_pkt_size);
>>> +		if (ret != 0)
>>> +			return ret;
>>> +	}
>>
>> <end-of-huge-dup>
>>
>> IMO It is not acceptable to duplication so much code.
>> It is simply unmaintainable.
>>
>> NACK
> 
> Can it be solved by making rte_eth_rx_queue_setup() a wrapper
> on top of this new rte_eth_rxseg_queue_setup() ?
> 

Could be, but strictly speaking it will break arguments
validation order and error reporting in various cases.
So, refactoring is required to keep it consistent.