Re: [dpdk-dev] [PATCH 1/7] ethdev: add set ptype function

[Andrew Rybchenko <arybchenko@solarflare.com>]

The patch should add item in release notes (as well as all other
subsequent patches which add more features).

On 8/16/19 8:55 AM, pbhagavatula@marvell.com wrote:
> From: Pavan Nikhilesh <pbhagavatula@marvell.com>
>
> Add `rte_eth_dev_set_supported_ptypes` function that will allow the
> application to inform the PMD the packet types it is interested in.
> Based on the ptypes set PMDs can optimize their Rx path.
>
> -If application doesn’t want any ptype information it can call
> `rte_eth_dev_set_supported_ptypes(ethdev_id, RTE_PTYPE_UNKNOWN)` and PMD
> will set rte_mbuf::packet_type to 0.

As I understand PMD may provide more reach classification
than set. So, it is not obliged to set packet type to 0.

> -If application doesn’t call `rte_eth_dev_set_supported_ptypes` PMD can
> return `rte_mbuf::packet_type` with `rte_eth_dev_get_supported_ptypes`.
>
> -If application is interested only in L2/L3 layer, it can inform the PMD
> to update `rte_mbuf::packet_type` with L2/L3 ptype by calling
> `rte_eth_dev_set_supported_ptypes(ethdev_id,
> 		RTE_PTYPE_L2_MASK | RTE_PTYPE_L3_MASK)`.
>
> Suggested-by: Konstantin Ananyev <konstantin.ananyev@intel.com>
> Signed-off-by: Pavan Nikhilesh <pbhagavatula@marvell.com>
> ---
>   doc/guides/nics/features.rst        | 12 ++++++++----
>   lib/librte_ethdev/rte_ethdev.c      | 28 ++++++++++++++++++++++++++++
>   lib/librte_ethdev/rte_ethdev.h      | 17 +++++++++++++++++
>   lib/librte_ethdev/rte_ethdev_core.h |  6 ++++++
>   4 files changed, 59 insertions(+), 4 deletions(-)
>
> diff --git a/doc/guides/nics/features.rst b/doc/guides/nics/features.rst
> index c4e128d2f..d4d55f721 100644
> --- a/doc/guides/nics/features.rst
> +++ b/doc/guides/nics/features.rst
> @@ -582,10 +582,14 @@ Supports inner packet L4 checksum.
>   Packet type parsing
>   -------------------
>
> -Supports packet type parsing and returns a list of supported types.
> -
> -* **[implements] eth_dev_ops**: ``dev_supported_ptypes_get``.
> -* **[related]    API**: ``rte_eth_dev_get_supported_ptypes()``.
> +Supports packet type parsing and returns a list of supported types. Allows
> +application to set ptypes it is interested in.
> +
> +* **[implements] eth_dev_ops**: ``dev_supported_ptypes_get``,
> +  ``dev_supported_ptypes_set``.
> +* **[related]    API**: ``rte_eth_dev_get_supported_ptypes()``,
> +  ``rte_eth_dev_set_supported_ptypes()``.
> +* **[provides]   mbuf**: ``mbuf.packet_type``.
>
>
>   .. _nic_features_timesync:
> diff --git a/lib/librte_ethdev/rte_ethdev.c b/lib/librte_ethdev/rte_ethdev.c
> index 17d183e1f..72fe660c3 100644
> --- a/lib/librte_ethdev/rte_ethdev.c
> +++ b/lib/librte_ethdev/rte_ethdev.c
> @@ -2602,6 +2602,34 @@ rte_eth_dev_get_supported_ptypes(uint16_t port_id, uint32_t ptype_mask,
>   	return j;
>   }
>
> +int
> +rte_eth_dev_set_supported_ptypes(uint16_t port_id, uint32_t ptype_mask)
> +{
> +	int i;
> +	struct rte_eth_dev *dev;
> +	const uint32_t *all_ptypes;
> +	uint32_t all_ptype_mask = 0;
> +
> +	RTE_ETH_VALID_PORTID_OR_ERR_RET(port_id, -ENODEV);
> +	dev = &rte_eth_devices[port_id];
> +	RTE_FUNC_PTR_OR_ERR_RET(*dev->dev_ops->dev_supported_ptypes_set,
> +				-ENOTSUP);
> +	RTE_FUNC_PTR_OR_ERR_RET(*dev->dev_ops->dev_supported_ptypes_get,
> +				-ENOTSUP);
> +	all_ptypes = (*dev->dev_ops->dev_supported_ptypes_get)(dev);
> +
> +	if (!all_ptypes)

If I remember correctly DPDK style prefers to compare vs 0.

> +		return -ENOTSUP;
> +
> +	for (i = 0; all_ptypes[i] != RTE_PTYPE_UNKNOWN; ++i)
> +		all_ptype_mask |= all_ptypes[i];
> +
> +	if ((all_ptype_mask & ptype_mask) != ptype_mask)
> +		return -ENOTSUP;

Do we really want so strict check here? May be just check
that intersection is not empty if ptype_mask is not empty?

I think that setting ptype_mask to 0 could be pretty often and
may be it makes sense to avoid get in the case. Also consider
to return OK even if there is no get/set callbacks at all.

> +
> +	return (*dev->dev_ops->dev_supported_ptypes_set)(dev, ptype_mask);
> +}
> +
>   void
>   rte_eth_macaddr_get(uint16_t port_id, struct rte_ether_addr *mac_addr)
>   {
> diff --git a/lib/librte_ethdev/rte_ethdev.h b/lib/librte_ethdev/rte_ethdev.h
> index dc6596bc9..f97f0a6e5 100644
> --- a/lib/librte_ethdev/rte_ethdev.h
> +++ b/lib/librte_ethdev/rte_ethdev.h
> @@ -2431,6 +2431,23 @@ int rte_eth_dev_fw_version_get(uint16_t port_id,
>    */
>   int rte_eth_dev_get_supported_ptypes(uint16_t port_id, uint32_t ptype_mask,
>   				     uint32_t *ptypes, int num);
> +/**
> + * Request Ethernet device to set only specific packet types in the packet.
> + *
> + * Application can use this function to set only specific ptypes that it's
> + * interested. This information can be used by the PMD to optimize Rx path.
> + *
> + * @param port_id
> + *   The port identifier of the Ethernet device.
> + * @param ptype_mask
> + *   The ptype family that application is interested in.
> + * @return
> + *   - (0) Successfully set supported ptypes.
> + *   - (-ENODEV) if *port_id* is invalid.
> + *   - (-ENOTSUP) Packet type mask supplied is not supported by the Ethernet
> + *		  device.
> + */
> +int rte_eth_dev_set_supported_ptypes(uint16_t port_id, uint32_t ptype_mask);

Should it be experimental?

Please, add it to .map file.

>   /**
>    * Retrieve the MTU of an Ethernet device.
> diff --git a/lib/librte_ethdev/rte_ethdev_core.h b/lib/librte_ethdev/rte_ethdev_core.h
> index 2922d5b7c..02ee7c12c 100644
> --- a/lib/librte_ethdev/rte_ethdev_core.h
> +++ b/lib/librte_ethdev/rte_ethdev_core.h
> @@ -110,6 +110,10 @@ typedef void (*eth_dev_infos_get_t)(struct rte_eth_dev *dev,
>   typedef const uint32_t *(*eth_dev_supported_ptypes_get_t)(struct rte_eth_dev *dev);
>   /**< @internal Get supported ptypes of an Ethernet device. */
>
> +typedef int (*eth_dev_supported_ptypes_set_t)(struct rte_eth_dev *dev,
> +					      uint32_t ptype_mask);
> +/**< @internal Set required ptypes of an Ethernet device. */
> +
>   typedef int (*eth_queue_start_t)(struct rte_eth_dev *dev,
>   				    uint16_t queue_id);
>   /**< @internal Start rx and tx of a queue of an Ethernet device. */
> @@ -421,6 +425,8 @@ struct eth_dev_ops {
>   	eth_fw_version_get_t       fw_version_get; /**< Get firmware version. */
>   	eth_dev_supported_ptypes_get_t dev_supported_ptypes_get;
>   	/**< Get packet types supported and identified by device. */
> +	eth_dev_supported_ptypes_set_t dev_supported_ptypes_set;
> +	/**< Inform device about the interested ptypes. */
>
>   	vlan_filter_set_t          vlan_filter_set; /**< Filter VLAN Setup. */
>   	vlan_tpid_set_t            vlan_tpid_set; /**< Outer/Inner VLAN TPID Setup. */
> --
> 2.22.0
>