On Tue, Jan 18, 2022 at 9:01 PM Alexander Kozyrev <akozy...@nvidia.com> wrote:
>
> The flow rules creation/destruction at a large scale incurs a performance
> penalty and may negatively impact the packet processing when used
> as part of the datapath logic. This is mainly because software/hardware
> resources are allocated and prepared during the flow rule creation.
>
> In order to optimize the insertion rate, PMD may use some hints provided
> by the application at the initialization phase. The rte_flow_configure()
> function allows to pre-allocate all the needed resources beforehand.
> These resources can be used at a later stage without costly allocations.
> Every PMD may use only the subset of hints and ignore unused ones or
> fail in case the requested configuration is not supported.
>
> Signed-off-by: Alexander Kozyrev <akozy...@nvidia.com>
> ---
>
> +/**
> + * @warning
> + * @b EXPERIMENTAL: this API may change without prior notice.
> + *
> + * Flow engine port configuration attributes.
> + */
> +__extension__
Is this __extension__ required ?
> +struct rte_flow_port_attr {
> + /**
> + * Version of the struct layout, should be 0.
> + */
> + uint32_t version;
Why version number? Across DPDK, we are using dynamic function
versioning, I think, that would
be sufficient for ABI versioning
> + /**
> + * Number of counter actions pre-configured.
> + * If set to 0, PMD will allocate counters dynamically.
> + * @see RTE_FLOW_ACTION_TYPE_COUNT
> + */
> + uint32_t nb_counters;
> + /**
> + * Number of aging actions pre-configured.
> + * If set to 0, PMD will allocate aging dynamically.
> + * @see RTE_FLOW_ACTION_TYPE_AGE
> + */
> + uint32_t nb_aging;
> + /**
> + * Number of traffic metering actions pre-configured.
> + * If set to 0, PMD will allocate meters dynamically.
> + * @see RTE_FLOW_ACTION_TYPE_METER
> + */
> + uint32_t nb_meters;
> +};
> +
> +/**
> + * @warning
> + * @b EXPERIMENTAL: this API may change without prior notice.
> + *
> + * Configure flow rules module.
> + * To pre-allocate resources as per the flow port attributes
> + * this configuration function must be called before any flow rule is
> created.
> + * Must be called only after Ethernet device is configured, but may be called
> + * before or after the device is started as long as there are no flow rules.
> + * No other rte_flow function should be called while this function is
> invoked.
> + * This function can be called again to change the configuration.
> + * Some PMDs may not support re-configuration at all,
> + * or may only allow increasing the number of resources allocated.
Following comment from Ivan looks good to me
* Pre-configure the port's flow API engine.
*
* This API can only be invoked before the application
* starts using the rest of the flow library functions.
*
* The API can be invoked multiple times to change the
* settings. The port, however, may reject the changes.
> + *
> + * @param port_id
> + * Port identifier of Ethernet device.
> + * @param[in] port_attr
> + * Port configuration attributes.
> + * @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_configure(uint16_t port_id,
Should we couple, setting resource limit hint to configure function as
if we add future items in
configuration, we may pain to manage all state. Instead how about,
rte_flow_resource_reserve_hint_set()?
> + const struct rte_flow_port_attr *port_attr,
> + struct rte_flow_error *error);
I think, we should have _get function to get those limit numbers otherwise,
we can not write portable applications as the return value is kind of
boolean now if
don't define exact values for rte_errno for reasons.
> +
> #ifdef __cplusplus
> }
> #endif
> diff --git a/lib/ethdev/rte_flow_driver.h b/lib/ethdev/rte_flow_driver.h
> index f691b04af4..5f722f1a39 100644
> --- a/lib/ethdev/rte_flow_driver.h
> +++ b/lib/ethdev/rte_flow_driver.h
> @@ -152,6 +152,11 @@ struct rte_flow_ops {
> (struct rte_eth_dev *dev,
> const struct rte_flow_item_flex_handle *handle,
> struct rte_flow_error *error);
> + /** See rte_flow_configure() */
> + int (*configure)
> + (struct rte_eth_dev *dev,
> + const struct rte_flow_port_attr *port_attr,
> + struct rte_flow_error *err);
> };
>
> /**
> diff --git a/lib/ethdev/version.map b/lib/ethdev/version.map
> index c2fb0669a4..7645796739 100644
> --- a/lib/ethdev/version.map
> +++ b/lib/ethdev/version.map
> @@ -256,6 +256,9 @@ EXPERIMENTAL {
> rte_flow_flex_item_create;
> rte_flow_flex_item_release;
> rte_flow_pick_transfer_proxy;
> +
> + # added in 22.03
> + rte_flow_configure;
> };
>
> INTERNAL {
> --
> 2.18.2
>
