Re: [PATCH v3 1/1] ethdev: support congestion management

[Andrew Rybchenko <andrew.rybchenko@oktetlabs.ru>]

On 9/29/22 12:35, skori@marvell.com wrote:
> From: Jerin Jacob <jerinj@marvell.com>
> 
> NIC HW controllers often come with congestion management support on
> various HW objects such as Rx queue depth or mempool queue depth.
> 
> Also, it can support various modes of operation such as RED
> (Random early discard), WRED etc on those HW objects.
> 
> This patch adds a framework to express such modes(enum rte_cman_mode)
> and introduce (enum rte_eth_cman_obj) to enumerate the different
> objects where the modes can operate on.
> 
> This patch adds RTE_CMAN_RED mode of operation and

This patch adds -> Add

> RTE_ETH_CMAN_OBJ_RX_QUEUE, RTE_ETH_CMAN_OBJ_RX_QUEUE_MEMPOOL object.
> 
> Introduced reserved fields in configuration structure

Introduce

> backed by rte_eth_cman_config_init() to add new configuration
> parameters without ABI breakage.
> 
> Added rte_eth_cman_info_get() API to get the information such as

Add

> supported modes and objects.
> 
> Added rte_eth_cman_config_init(), rte_eth_cman_config_set() APIs

Add

> to configure congestion management on those object with associated mode.
> 
> Finally, Added rte_eth_cman_config_get() API to retrieve the

add

> applied configuration.
> 
> Signed-off-by: Jerin Jacob <jerinj@marvell.com>
> Signed-off-by: Sunil Kumar Kori <skori@marvell.com>

I'll send v4 with few minor correction.

> ---
> v2..v3:
>   - Rename rte_cman.c to rte_ethdev_cman.c
>   - Move lib/eal/include/rte_cman.h to lib/ethdev/rte_cman.h
>   - Fix review comments (Andrew Rybchenko)
>   - Add release notes
> 
> v1..v2:
>   - Fix review comments (Akhil Goyal)
> 
> rfc..v1:
>   - Added RED specification (http://www.aciri.org/floyd/papers/red/red.html) link
>   - Fixed doxygen comment issue (Min Hu)
> 
>   doc/guides/nics/features.rst           |  12 ++
>   doc/guides/nics/features/default.ini   |   1 +
>   doc/guides/rel_notes/release_22_11.rst |   6 +
>   lib/ethdev/ethdev_driver.h             |  25 ++++
>   lib/ethdev/ethdev_private.c            |  12 ++
>   lib/ethdev/ethdev_private.h            |   2 +
>   lib/ethdev/meson.build                 |   2 +
>   lib/ethdev/rte_cman.h                  |  55 +++++++++
>   lib/ethdev/rte_ethdev.h                | 164 +++++++++++++++++++++++++
>   lib/ethdev/rte_ethdev_cman.c           | 101 +++++++++++++++
>   lib/ethdev/version.map                 |   6 +
>   11 files changed, 386 insertions(+)
>   create mode 100644 lib/ethdev/rte_cman.h
>   create mode 100644 lib/ethdev/rte_ethdev_cman.c
> 
> diff --git a/doc/guides/nics/features.rst b/doc/guides/nics/features.rst
> index b4a8e9881c..70ca46e651 100644
> --- a/doc/guides/nics/features.rst
> +++ b/doc/guides/nics/features.rst
> @@ -727,6 +727,18 @@ Supports configuring per-queue stat counter mapping.
>     ``rte_eth_dev_set_tx_queue_stats_mapping()``.
>   
>   
> +.. _nic_features_congestion_management:
> +
> +Congestion management
> +---------------------
> +
> +Supports congestion management.
> +
> +* **[implements] eth_dev_ops**: ``cman_info_get``, ``cman_config_set``, ``cman_config_get``.
> +* **[related]    API**: ``rte_eth_cman_info_get()``, ``rte_eth_cman_config_init()``,
> +  ``rte_eth_cman_config_set()``, ``rte_eth_cman_config_get()``.
> +
> +
>   .. _nic_features_fw_version:
>   
>   FW version
> diff --git a/doc/guides/nics/features/default.ini b/doc/guides/nics/features/default.ini
> index f7192cb0da..a9c0008ebd 100644
> --- a/doc/guides/nics/features/default.ini
> +++ b/doc/guides/nics/features/default.ini
> @@ -60,6 +60,7 @@ Tx descriptor status =
>   Basic stats          =
>   Extended stats       =
>   Stats per queue      =
> +Congestion management =
>   FW version           =
>   EEPROM dump          =
>   Module EEPROM dump   =
> diff --git a/doc/guides/rel_notes/release_22_11.rst b/doc/guides/rel_notes/release_22_11.rst
> index 0231959874..ea9908e578 100644
> --- a/doc/guides/rel_notes/release_22_11.rst
> +++ b/doc/guides/rel_notes/release_22_11.rst
> @@ -81,6 +81,12 @@ New Features
>     * Added AES-CCM support in lookaside protocol (IPsec) for CN9K & CN10K.
>     * Added AES & DES DOCSIS algorithm support in lookaside crypto for CN9K.
>   
> +* **Added support for congestion management for ethdev.**
> +
> +  Added new APIs ``rte_eth_cman_config_init()``, ``rte_eth_cman_config_get()``,
> +  ``rte_eth_cman_config_set()``, ``rte_eth_cman_info_get()``
> +  to support congestion management.
> +

The position is a bit incorrect. It should go after ethdev
items.

>   * **Added eventdev adapter instance get API.**
>   
>     * Added ``rte_event_eth_rx_adapter_instance_get`` to get Rx adapter
> diff --git a/lib/ethdev/ethdev_driver.h b/lib/ethdev/ethdev_driver.h
> index 8cd8eb8685..e1e2d10a35 100644
> --- a/lib/ethdev/ethdev_driver.h
> +++ b/lib/ethdev/ethdev_driver.h
> @@ -1094,6 +1094,22 @@ typedef int (*eth_rx_queue_avail_thresh_query_t)(struct rte_eth_dev *dev,
>   					uint16_t *rx_queue_id,
>   					uint8_t *avail_thresh);
>   
> +/** @internal Get congestion management information. */
> +typedef int (*eth_cman_info_get_t)(struct rte_eth_dev *dev,
> +				struct rte_eth_cman_info *info);
> +
> +/** @internal Init congestion management structure with default values. */
> +typedef int (*eth_cman_config_init_t)(struct rte_eth_dev *dev,
> +				struct rte_eth_cman_config *config);
> +
> +/** @internal Configure congestion management on a port. */
> +typedef int (*eth_cman_config_set_t)(struct rte_eth_dev *dev,
> +				const struct rte_eth_cman_config *config);
> +
> +/** @internal Retrieve congestion management configuration of a port. */
> +typedef int (*eth_cman_config_get_t)(struct rte_eth_dev *dev,
> +				struct rte_eth_cman_config *config);
> +
>   /**
>    * @internal A structure containing the functions exported by an Ethernet driver.
>    */
> @@ -1309,6 +1325,15 @@ struct eth_dev_ops {
>   	eth_rx_queue_avail_thresh_set_t rx_queue_avail_thresh_set;
>   	/** Query Rx queue available descriptors threshold event */
>   	eth_rx_queue_avail_thresh_query_t rx_queue_avail_thresh_query;
> +
> +	/** Get congestion management information */
> +	eth_cman_info_get_t cman_info_get;
> +	/** Initialize congestion management structure with default values */
> +	eth_cman_config_init_t cman_config_init;
> +	/** Configure congestion management */
> +	eth_cman_config_set_t cman_config_set;
> +	/** Retrieve congestion management configuration */
> +	eth_cman_config_get_t cman_config_get;
>   };
>   
>   /**
> diff --git a/lib/ethdev/ethdev_private.c b/lib/ethdev/ethdev_private.c
> index 48090c879a..8787c3985e 100644
> --- a/lib/ethdev/ethdev_private.c
> +++ b/lib/ethdev/ethdev_private.c
> @@ -27,6 +27,18 @@ eth_dev_to_id(const struct rte_eth_dev *dev)
>   	return dev - rte_eth_devices;
>   }
>   
> +int32_t
> +eth_check_err(struct rte_eth_dev *dev, int ret)
> +{
> +	if (ret == 0)
> +		return 0;
> +
> +	if (rte_eth_dev_is_removed(eth_dev_to_id(dev)))
> +		return -EIO;
> +
> +	return ret;
> +}

It still duplicates eth_err(). I realize the difference in the
first argument, but I think it is better to stick to eth_err().
Anyway eth_check_err() gets port_id by device and it is the
only usage of the device in the function.

[snip]