RE: [PATCH] ethdev: add flow rule actions update API

[Ori Kam <orika@nvidia.com>]

Hi Alexander,

Please add rte_flow_trace_xxx for all new functions.

> -----Original Message-----
> From: Alexander Kozyrev <akozyrev@nvidia.com>
> Sent: Tuesday, April 18, 2023 10:58 PM
> 
> Introduce the new rte_flow_update() API allowing users
> to update the action list in the already existing rule.
> Flow rules can be updated now without the need to destroy
> the rule first and create a new one instead.
> A single API call ensures that no packets are lost by
> guaranteeing atomicity and flow state correctness.
> The rte_flow_async_update() is added as well.
> The matcher is not updated, only the action list is.
> 
> Signed-off-by: Alexander Kozyrev <akozyrev@nvidia.com>
> ---
>  doc/guides/prog_guide/rte_flow.rst     | 42 +++++++++++++++++
>  doc/guides/rel_notes/release_23_07.rst |  4 ++
>  lib/ethdev/rte_flow.c                  | 43 ++++++++++++++++++
>  lib/ethdev/rte_flow.h                  | 62 ++++++++++++++++++++++++++
>  lib/ethdev/rte_flow_driver.h           | 16 +++++++
>  lib/ethdev/version.map                 |  2 +
>  6 files changed, 169 insertions(+)
> 
> diff --git a/doc/guides/prog_guide/rte_flow.rst
> b/doc/guides/prog_guide/rte_flow.rst
> index 32fc45516a..0930accfea 100644
> --- a/doc/guides/prog_guide/rte_flow.rst
> +++ b/doc/guides/prog_guide/rte_flow.rst
> @@ -3446,6 +3446,31 @@ Return values:
> 
>  - 0 on success, a negative errno value otherwise and ``rte_errno`` is set.
> 
> +Update
> +~~~~~~
> +
> +Update an existing flow rule with a new set of actions.
> +
> +.. code-block:: c
> +
> +   struct rte_flow *
> +   rte_flow_update(uint16_t port_id,
> +                   struct rte_flow *flow,
> +                   const struct rte_flow_action *actions[],
> +                   struct rte_flow_error *error);
> +
> +Arguments:
> +
> +- ``port_id``: port identifier of Ethernet device.
> +- ``flow``: flow rule handle to update.
> +- ``actions``: associated actions (list terminated by the END action).
> +- ``error``: perform verbose error reporting if not NULL. PMDs initialize
> +  this structure in case of error only.
> +
> +Return values:
> +
> +- 0 on success, a negative errno value otherwise and ``rte_errno`` is set.
> +
>  Flush
>  ~~~~~
> 
> @@ -3795,6 +3820,23 @@ Enqueueing a flow rule destruction operation is
> similar to simple destruction.
>                            void *user_data,
>                            struct rte_flow_error *error);
> 
> +Enqueue update operation
> +~~~~~~~~~~~~~~~~~~~~~~~~~~
> +
> +Enqueueing a flow rule update operation to replace actions in the existing
> rule.
> +
> +.. code-block:: c
> +
> +   int
> +   rte_flow_async_update(uint16_t port_id,
> +                         uint32_t queue_id,
> +                         const struct rte_flow_op_attr *op_attr,
> +                         struct rte_flow *flow,
> +                         const struct rte_flow_action actions[],
> +                         uint8_t actions_template_index,
> +                         void *user_data,
> +                         struct rte_flow_error *error);
> +
>  Enqueue indirect action creation operation
>  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> 
> diff --git a/doc/guides/rel_notes/release_23_07.rst
> b/doc/guides/rel_notes/release_23_07.rst
> index a9b1293689..94e9f8b3ae 100644
> --- a/doc/guides/rel_notes/release_23_07.rst
> +++ b/doc/guides/rel_notes/release_23_07.rst
> @@ -55,6 +55,10 @@ New Features
>       Also, make sure to start the actual text at the margin.
>       =======================================================
> 
> +   * **Added flow rule update to the Flow API.**
> +
> +     * Added API for updating the action list in the already existing rule.
> +       Introduced both rte_flow_update() and rte_flow_async_update()
> functions.
> 
>  Removed Items
>  -------------
> diff --git a/lib/ethdev/rte_flow.c b/lib/ethdev/rte_flow.c
> index 69e6e749f7..1ebb17ae3c 100644
> --- a/lib/ethdev/rte_flow.c
> +++ b/lib/ethdev/rte_flow.c
> @@ -441,6 +441,29 @@ rte_flow_destroy(uint16_t port_id,
>  				  NULL, rte_strerror(ENOSYS));
>  }
> 
> +int
> +rte_flow_update(uint16_t port_id,
> +		struct rte_flow *flow,
> +		const struct rte_flow_action actions[],
> +		struct rte_flow_error *error)
> +{
> +	struct rte_eth_dev *dev = &rte_eth_devices[port_id];
> +	const struct rte_flow_ops *ops = rte_flow_ops_get(port_id, error);
> +	int ret;
> +
> +	if (unlikely(!ops))
> +		return -rte_errno;
> +	if (likely(!!ops->update)) {
> +		fts_enter(dev);
> +		ret = ops->update(dev, flow, actions, error);
> +		fts_exit(dev);
> +		return flow_err(port_id, ret, error);
> +	}
> +	return rte_flow_error_set(error, ENOSYS,
> +				  RTE_FLOW_ERROR_TYPE_UNSPECIFIED,
> +				  NULL, rte_strerror(ENOSYS));
> +}
> +
>  /* Destroy all flow rules associated with a port. */
>  int
>  rte_flow_flush(uint16_t port_id,
> @@ -1985,6 +2008,26 @@ rte_flow_async_destroy(uint16_t port_id,
>  	return ret;
>  }
> 
> +int
> +rte_flow_async_update(uint16_t port_id,
> +		      uint32_t queue_id,
> +		      const struct rte_flow_op_attr *op_attr,
> +		      struct rte_flow *flow,
> +		      const struct rte_flow_action actions[],
> +		      uint8_t actions_template_index,
> +		      void *user_data,
> +		      struct rte_flow_error *error)
> +{
> +	struct rte_eth_dev *dev = &rte_eth_devices[port_id];
> +	const struct rte_flow_ops *ops = rte_flow_ops_get(port_id, error);
> +
> +	return flow_err(port_id,
> +			ops->async_update(dev, queue_id, op_attr, flow,
> +					  actions, actions_template_index,
> +					  user_data, error),
> +			error);
> +}
> +
>  int
>  rte_flow_push(uint16_t port_id,
>  	      uint32_t queue_id,
> diff --git a/lib/ethdev/rte_flow.h b/lib/ethdev/rte_flow.h
> index 713ba8b65c..79bfc07a1c 100644
> --- a/lib/ethdev/rte_flow.h
> +++ b/lib/ethdev/rte_flow.h
> @@ -4343,6 +4343,29 @@ rte_flow_destroy(uint16_t port_id,
>  		 struct rte_flow *flow,
>  		 struct rte_flow_error *error);
> 
> +/**
> + * Update a flow rule with new actions on a given port.
> + *
> + * @param port_id
> + *   Port identifier of Ethernet device.
> + * @param flow
> + *   Flow rule handle to update.
> + * @param[in] actions
> + *   Associated actions (list terminated by the END action).
> + * @param[out] error
> + *   Perform verbose error reporting if not NULL. PMDs initialize this
> + *   structure in case of error only.
> + *
> + * @return
> + *   0 on success, a negative errno value otherwise and rte_errno is set.
> + */
> +__rte_experimental
> +int
> +rte_flow_update(uint16_t port_id,
> +		struct rte_flow *flow,
> +		const struct rte_flow_action actions[],
> +		struct rte_flow_error *error);
> +
>  /**
>   * Destroy all flow rules associated with a port.
>   *
> @@ -5770,6 +5793,45 @@ rte_flow_async_destroy(uint16_t port_id,
>  		       void *user_data,
>  		       struct rte_flow_error *error);
> 
> +/**
> + * @warning
> + * @b EXPERIMENTAL: this API may change without prior notice.
> + *
> + * Enqueue rule update operation.
> + *
> + * @param port_id
> + *   Port identifier of Ethernet device.
> + * @param queue_id
> + *   Flow queue used to insert the rule.
> + * @param[in] op_attr
> + *   Rule creation operation attributes.
> + * @param[in] flow
> + *   Flow rule to be updated.
> + * @param[in] actions
> + *   List of actions to be used.
> + *   The list order should match the order in the actions template.
> + * @param[in] actions_template_index
> + *   Actions template index in the table.
> + * @param[in] user_data
> + *   The user data that will be returned on the completion events.
> + * @param[out] error
> + *   Perform verbose error reporting if not NULL.
> + *   PMDs initialize this structure in case of error only.
> + *
> + * @return
> + *   0 on success, a negative errno value otherwise and rte_errno is set.
> + */
> +__rte_experimental
> +int
> +rte_flow_async_update(uint16_t port_id,
> +		      uint32_t queue_id,
> +		      const struct rte_flow_op_attr *op_attr,
> +		      struct rte_flow *flow,
> +		      const struct rte_flow_action actions[],
> +		      uint8_t actions_template_index,
> +		      void *user_data,
> +		      struct rte_flow_error *error);
> +
>  /**
>   * @warning
>   * @b EXPERIMENTAL: this API may change without prior notice.
> diff --git a/lib/ethdev/rte_flow_driver.h b/lib/ethdev/rte_flow_driver.h
> index a129a4605d..193b09a7d3 100644
> --- a/lib/ethdev/rte_flow_driver.h
> +++ b/lib/ethdev/rte_flow_driver.h
> @@ -302,6 +302,22 @@ struct rte_flow_ops {
>  		 const void *update, void *query,
>  		 enum rte_flow_query_update_mode qu_mode,
>  		 void *user_data, struct rte_flow_error *error);
> +	/** See rte_flow_update(). */
> +	int (*update)
> +		(struct rte_eth_dev *dev,
> +		 struct rte_flow *flow,
> +		 const struct rte_flow_action actions[],
> +		 struct rte_flow_error *error);
> +	/** See rte_flow_async_update() */
> +	int (*async_update)
> +		(struct rte_eth_dev *dev,
> +		 uint32_t queue_id,
> +		 const struct rte_flow_op_attr *op_attr,
> +		 struct rte_flow *flow,
> +		 const struct rte_flow_action actions[],
> +		 uint8_t actions_template_index,
> +		 void *user_data,
> +		 struct rte_flow_error *error);
>  };
> 
>  /**
> diff --git a/lib/ethdev/version.map b/lib/ethdev/version.map
> index 357d1a88c0..d4f49cb918 100644
> --- a/lib/ethdev/version.map
> +++ b/lib/ethdev/version.map
> @@ -299,6 +299,8 @@ EXPERIMENTAL {
>  	rte_flow_action_handle_query_update;
>  	rte_flow_async_action_handle_query_update;
>  	rte_flow_async_create_by_index;
> +	rte_flow_update;
> +	rte_flow_async_update;
>  };
> 
>  INTERNAL {
> --
> 2.18.2

Best,
Ori