[v6,1/3] ethdev: support mulitiple mbuf pools per Rx queue

  This patch adds support for multiple mempool capability.
Some of the HW has support for choosing memory pools based on the
packet's size. The capability allows PMD to choose a memory pool
based on the packet's length.

This is often useful for saving the memory where the application
can create a different pool to steer the specific size of the
packet, thus enabling effective use of memory.

For example, let's say HW has a capability of three pools,
 - pool-1 size is 2K
 - pool-2 size is > 2K and < 4K
 - pool-3 size is > 4K
Here,
        pool-1 can accommodate packets with sizes < 2K
        pool-2 can accommodate packets with sizes > 2K and < 4K
        pool-3 can accommodate packets with sizes > 4K

With multiple mempool capability enabled in SW, an application may
create three pools of different sizes and send them to PMD. Allowing
PMD to program HW based on the packet lengths. So that packets with
less than 2K are received on pool-1, packets with lengths between 2K
and 4K are received on pool-2 and finally packets greater than 4K
are received on pool-3.

Signed-off-by: Hanumanth Pothula <hpothula@marvell.com>

v6:
 - Updated release notes, release_22_11.rst.
v5:
 - Declared memory pools as struct rte_mempool **rx_mempools rather than
   as struct rte_mempool *mp.
 - Added the feature in release notes.
 - Updated conditions and strings as per review comments.
v4:
 - Renamed Offload capability name from RTE_ETH_RX_OFFLOAD_BUFFER_SORT
   to RTE_ETH_RX_OFFLOAD_MUL_MEMPOOL.
 - In struct rte_eth_rxconf, defined new pointer, which holds array of
   type struct rte_eth_rx_mempool(memory pools). This array is used
   by PMD to program multiple mempools.
v3:
 - Implemented Pool Sort capability as new Rx offload capability,
   RTE_ETH_RX_OFFLOAD_BUFFER_SORT.
v2:
 - Along with spec changes, uploading testpmd and driver changes.
---
 doc/guides/rel_notes/release_22_11.rst |  6 +++
 lib/ethdev/rte_ethdev.c                | 74 ++++++++++++++++++++++----
 lib/ethdev/rte_ethdev.h                | 22 ++++++++
 3 files changed, 92 insertions(+), 10 deletions(-)
  

Hello Andrew/Thomas/Ferruh,

Thank You for your comments. I have taken care and uploaded new patch-set.
As tomorrow is RC1 release. Could you please help in reviewing the changes and in merging the changes, if changes looks good.

Regards,
Hanumanth 

> -----Original Message-----
> From: Hanumanth Pothula <hpothula@marvell.com>
> Sent: Thursday, October 6, 2022 11:24 PM
> To: Thomas Monjalon <thomas@monjalon.net>; Ferruh Yigit
> <ferruh.yigit@xilinx.com>; Andrew Rybchenko
> <andrew.rybchenko@oktetlabs.ru>
> Cc: dev@dpdk.org; xuan.ding@intel.com; wenxuanx.wu@intel.com;
> xiaoyun.li@intel.com; stephen@networkplumber.org; yuanx.wang@intel.com;
> mdr@ashroe.eu; yuying.zhang@intel.com; qi.z.zhang@intel.com;
> viacheslavo@nvidia.com; Jerin Jacob Kollanukkaran <jerinj@marvell.com>;
> Nithin Kumar Dabilpuram <ndabilpuram@marvell.com>; Hanumanth Reddy
> Pothula <hpothula@marvell.com>
> Subject: [PATCH v6 1/3] ethdev: support mulitiple mbuf pools per Rx queue
> 
> This patch adds support for multiple mempool capability.
> Some of the HW has support for choosing memory pools based on the packet's
> size. The capability allows PMD to choose a memory pool based on the packet's
> length.
> 
> This is often useful for saving the memory where the application can create a
> different pool to steer the specific size of the packet, thus enabling effective use
> of memory.
> 
> For example, let's say HW has a capability of three pools,
>  - pool-1 size is 2K
>  - pool-2 size is > 2K and < 4K
>  - pool-3 size is > 4K
> Here,
>         pool-1 can accommodate packets with sizes < 2K
>         pool-2 can accommodate packets with sizes > 2K and < 4K
>         pool-3 can accommodate packets with sizes > 4K
> 
> With multiple mempool capability enabled in SW, an application may create
> three pools of different sizes and send them to PMD. Allowing PMD to program
> HW based on the packet lengths. So that packets with less than 2K are received
> on pool-1, packets with lengths between 2K and 4K are received on pool-2 and
> finally packets greater than 4K are received on pool-3.
> 
> Signed-off-by: Hanumanth Pothula <hpothula@marvell.com>
> 
> v6:
>  - Updated release notes, release_22_11.rst.
> v5:
>  - Declared memory pools as struct rte_mempool **rx_mempools rather than
>    as struct rte_mempool *mp.
>  - Added the feature in release notes.
>  - Updated conditions and strings as per review comments.
> v4:
>  - Renamed Offload capability name from
> RTE_ETH_RX_OFFLOAD_BUFFER_SORT
>    to RTE_ETH_RX_OFFLOAD_MUL_MEMPOOL.
>  - In struct rte_eth_rxconf, defined new pointer, which holds array of
>    type struct rte_eth_rx_mempool(memory pools). This array is used
>    by PMD to program multiple mempools.
> v3:
>  - Implemented Pool Sort capability as new Rx offload capability,
>    RTE_ETH_RX_OFFLOAD_BUFFER_SORT.
> v2:
>  - Along with spec changes, uploading testpmd and driver changes.
> ---
>  doc/guides/rel_notes/release_22_11.rst |  6 +++
>  lib/ethdev/rte_ethdev.c                | 74 ++++++++++++++++++++++----
>  lib/ethdev/rte_ethdev.h                | 22 ++++++++
>  3 files changed, 92 insertions(+), 10 deletions(-)
> 
> diff --git a/doc/guides/rel_notes/release_22_11.rst
> b/doc/guides/rel_notes/release_22_11.rst
> index 2e076ba2ad..8bb19155d9 100644
> --- a/doc/guides/rel_notes/release_22_11.rst
> +++ b/doc/guides/rel_notes/release_22_11.rst
> @@ -55,6 +55,12 @@ New Features
>       Also, make sure to start the actual text at the margin.
>       =======================================================
> 
> +* ** Added support ethdev support for mulitiple mbuf pools per Rx
> +queue.**
> +
> +  * Added new Rx offload flag ``RTE_ETH_RX_OFFLOAD_MUL_MEMPOOL`` to
> support
> +    mulitiple mbuf pools per Rx queue. Thisi capability allows PMD to choose
> +    a memory pool based on the packet's length
> +
>  * **Updated Wangxun ngbe driver.**
> 
>    * Added support to set device link down/up.
> diff --git a/lib/ethdev/rte_ethdev.c b/lib/ethdev/rte_ethdev.c index
> 1979dc0850..eed4834e6b 100644
> --- a/lib/ethdev/rte_ethdev.c
> +++ b/lib/ethdev/rte_ethdev.c
> @@ -1634,6 +1634,44 @@ rte_eth_dev_is_removed(uint16_t port_id)
>  	return ret;
>  }
> 
> +static int
> +rte_eth_rx_queue_check_mempool(struct rte_mempool **rx_mempool,
> +			       uint16_t n_pool, uint32_t *mbp_buf_size,
> +			       const struct rte_eth_dev_info *dev_info) {
> +	uint16_t pool_idx;
> +
> +	if (n_pool > dev_info->max_pools) {
> +		RTE_ETHDEV_LOG(ERR,
> +			       "Too many Rx mempools %u vs maximum %u\n",
> +			       n_pool, dev_info->max_pools);
> +		return -EINVAL;
> +	}
> +
> +	for (pool_idx = 0; pool_idx < n_pool; pool_idx++) {
> +		struct rte_mempool *mpl = rx_mempool[pool_idx];
> +
> +		if (mpl == NULL) {
> +			RTE_ETHDEV_LOG(ERR, "null Rx mempool pointer\n");
> +			return -EINVAL;
> +		}
> +
> +		*mbp_buf_size = rte_pktmbuf_data_room_size(mpl);
> +		if (*mbp_buf_size < dev_info->min_rx_bufsize +
> +		    RTE_PKTMBUF_HEADROOM) {
> +			RTE_ETHDEV_LOG(ERR,
> +				       "%s mbuf_data_room_size %u < %u
> (RTE_PKTMBUF_HEADROOM=%u + min_rx_bufsize(dev)=%u)\n",
> +					mpl->name, *mbp_buf_size,
> +					RTE_PKTMBUF_HEADROOM +
> dev_info->min_rx_bufsize,
> +					RTE_PKTMBUF_HEADROOM,
> +					dev_info->min_rx_bufsize);
> +			return -EINVAL;
> +		}
> +	}
> +
> +	return 0;
> +}
> +
>  static int
>  rte_eth_rx_queue_check_split(const struct rte_eth_rxseg_split *rx_seg,
>  			     uint16_t n_seg, uint32_t *mbp_buf_size, @@ -
> 1733,9 +1771,12 @@ rte_eth_rx_queue_setup(uint16_t port_id, uint16_t
> rx_queue_id,
> 
>  	if (mp != NULL) {
>  		/* Single pool configuration check. */
> -		if (rx_conf != NULL && rx_conf->rx_nseg != 0) {
> +		if (((rx_conf->offloads &
> RTE_ETH_RX_OFFLOAD_BUFFER_SPLIT) &&
> +		    rx_conf != NULL && rx_conf->rx_nseg != 0) ||
> +		   ((rx_conf->offloads &
> RTE_ETH_RX_OFFLOAD_MUL_MEMPOOL) &&
> +		    rx_conf != NULL && rx_conf->rx_npool != 0)) {
>  			RTE_ETHDEV_LOG(ERR,
> -				       "Ambiguous segment configuration\n");
> +				       "Ambiguous Rx mempools
> configuration\n");
>  			return -EINVAL;
>  		}
>  		/*
> @@ -1763,30 +1804,43 @@ rte_eth_rx_queue_setup(uint16_t port_id, uint16_t
> rx_queue_id,
>  				       dev_info.min_rx_bufsize);
>  			return -EINVAL;
>  		}
> -	} else {
> +	} else if (rx_conf->offloads & RTE_ETH_RX_OFFLOAD_BUFFER_SPLIT) {
>  		const struct rte_eth_rxseg_split *rx_seg;
>  		uint16_t n_seg;
> 
>  		/* Extended multi-segment configuration check. */
>  		if (rx_conf == NULL || rx_conf->rx_seg == NULL || rx_conf-
> >rx_nseg == 0) {
>  			RTE_ETHDEV_LOG(ERR,
> -				       "Memory pool is null and no extended
> configuration provided\n");
> +				       "Memory pool is null and no multi-segment
> configuration
> +provided\n");
>  			return -EINVAL;
>  		}
> 
>  		rx_seg = (const struct rte_eth_rxseg_split *)rx_conf->rx_seg;
>  		n_seg = rx_conf->rx_nseg;
> 
> -		if (rx_conf->offloads & RTE_ETH_RX_OFFLOAD_BUFFER_SPLIT)
> {
> -			ret = rte_eth_rx_queue_check_split(rx_seg, n_seg,
> +		ret = rte_eth_rx_queue_check_split(rx_seg, n_seg,
>  							   &mbp_buf_size,
>  							   &dev_info);
> -			if (ret != 0)
> -				return ret;
> -		} else {
> -			RTE_ETHDEV_LOG(ERR, "No Rx segmentation offload
> configured\n");
> +		if (ret != 0)
> +			return ret;
> +	} else if (rx_conf->offloads & RTE_ETH_RX_OFFLOAD_MUL_MEMPOOL)
> {
> +		/* Extended multi-pool configuration check. */
> +		if (rx_conf == NULL || rx_conf->rx_mempools == NULL ||
> rx_conf->rx_npool == 0) {
> +			RTE_ETHDEV_LOG(ERR,
> +				       "Memory pool is null and no multi-pool
> configuration
> +provided\n");
>  			return -EINVAL;
>  		}
> +
> +		ret = rte_eth_rx_queue_check_mempool(rx_conf-
> >rx_mempools,
> +						     rx_conf->rx_npool,
> +						     &mbp_buf_size,
> +						     &dev_info);
> +
> +		if (ret != 0)
> +			return ret;
> +	} else {
> +		RTE_ETHDEV_LOG(ERR, "Missing Rx mempool
> configuration\n");
> +		return -EINVAL;
>  	}
> 
>  	/* Use default specified by driver, if nb_rx_desc is zero */ diff --git
> a/lib/ethdev/rte_ethdev.h b/lib/ethdev/rte_ethdev.h index
> b62ac5bb6f..306c2b3573 100644
> --- a/lib/ethdev/rte_ethdev.h
> +++ b/lib/ethdev/rte_ethdev.h
> @@ -1067,6 +1067,25 @@ struct rte_eth_rxconf {
>  	 */
>  	union rte_eth_rxseg *rx_seg;
> 
> +	/**
> +	 * Points to an array of mempools.
> +	 *
> +	 * Valid only when RTE_ETH_RX_OFFLOAD_MUL_MEMPOOL flag is set
> in
> +	 * Rx offloads.
> +	 *
> +	 * This provides support for  multiple mbuf pools per Rx queue.
> +	 *
> +	 * This is often useful for saving the memory where the application can
> +	 * create a different pools to steer the specific size of the packet, thus
> +	 * enabling effective use of memory.
> +	 *
> +	 * Note that on Rx scatter enable, a packet may be delivered using a
> chain
> +	 * of mbufs obtained from single mempool or multiple mempools based
> on
> +	 * the NIC implementation.
> +	 */
> +	struct rte_mempool **rx_mempools;
> +	uint16_t rx_npool; /** < number of mempools */
> +
>  	uint64_t reserved_64s[2]; /**< Reserved for future fields */
>  	void *reserved_ptrs[2];   /**< Reserved for future fields */
>  };
> @@ -1395,6 +1414,7 @@ struct rte_eth_conf {  #define
> RTE_ETH_RX_OFFLOAD_OUTER_UDP_CKSUM  RTE_BIT64(18)
>  #define RTE_ETH_RX_OFFLOAD_RSS_HASH         RTE_BIT64(19)
>  #define RTE_ETH_RX_OFFLOAD_BUFFER_SPLIT     RTE_BIT64(20)
> +#define RTE_ETH_RX_OFFLOAD_MUL_MEMPOOL      RTE_BIT64(21)
> 
>  #define RTE_ETH_RX_OFFLOAD_CHECKSUM
> (RTE_ETH_RX_OFFLOAD_IPV4_CKSUM | \
>  				 RTE_ETH_RX_OFFLOAD_UDP_CKSUM | \
> @@ -1615,6 +1635,8 @@ struct rte_eth_dev_info {
>  	/** Configured number of Rx/Tx queues */
>  	uint16_t nb_rx_queues; /**< Number of Rx queues. */
>  	uint16_t nb_tx_queues; /**< Number of Tx queues. */
> +	/** Maximum number of pools supported per Rx queue. */
> +	uint16_t max_pools;
>  	/** Rx parameter recommendations */
>  	struct rte_eth_dev_portconf default_rxportconf;
>  	/** Tx parameter recommendations */
> --
> 2.25.1