Hi Michael,
> -----Original Message-----
> From: Michael Savisko <michael...@nvidia.com>
> Sent: Wednesday, 14 September 2022 12:32
>
> In some cases application may receive a packet that should have been
> received by the kernel. In this case application uses KNI or other means
> to transfer the packet to the kernel.
>
> With bifurcated driver we can have a rule to route packets matching
> a pattern (example: IPv4 packets) to the DPDK application and the rest
> of the traffic will be received by the kernel.
> But if we want to receive most of the traffic in DPDK except specific
> pattern (example: ICMP packets) that should be processed by the kernel,
> then it's easier to re-route these packets with a single rule.
>
> This commit introduces new rte_flow action which allows application to
> re-route packets directly to the kernel without software involvement.
>
> Add new testpmd rte_flow action 'send_to_kernel'. The application
> may use this action to route the packet to the kernel while still
> in the HW.
>
> Example with testpmd command:
>
> flow create 0 ingress priority 0 group 1 pattern eth type spec 0x0800
> type mask 0xffff / end actions send_to_kernel / end
>
> Signed-off-by: Michael Savisko <michael...@nvidia.com>
> ---
> app/test-pmd/cmdline_flow.c | 9 +++++++++
> doc/guides/testpmd_app_ug/testpmd_funcs.rst | 2 ++
> lib/ethdev/rte_flow.c | 1 +
> lib/ethdev/rte_flow.h | 9 +++++++++
> 4 files changed, 21 insertions(+)
>
> diff --git a/app/test-pmd/cmdline_flow.c b/app/test-pmd/cmdline_flow.c
> index 7f50028eb7..042f6b34a6 100644
> --- a/app/test-pmd/cmdline_flow.c
> +++ b/app/test-pmd/cmdline_flow.c
> @@ -612,6 +612,7 @@ enum index {
> ACTION_PORT_REPRESENTOR_PORT_ID,
> ACTION_REPRESENTED_PORT,
> ACTION_REPRESENTED_PORT_ETHDEV_PORT_ID,
> + ACTION_SEND_TO_KERNEL,
> };
>
> /** Maximum size for pattern in struct rte_flow_item_raw. */
> @@ -1872,6 +1873,7 @@ static const enum index next_action[] = {
> ACTION_CONNTRACK_UPDATE,
> ACTION_PORT_REPRESENTOR,
> ACTION_REPRESENTED_PORT,
> + ACTION_SEND_TO_KERNEL,
> ZERO,
> };
>
> @@ -6341,6 +6343,13 @@ static const struct token token_list[] = {
> .help = "submit a list of associated actions for red",
> .next = NEXT(next_action),
> },
> + [ACTION_SEND_TO_KERNEL] = {
> + .name = "send_to_kernel",
> + .help = "send packets to kernel",
> + .priv = PRIV_ACTION(SEND_TO_KERNEL, 0),
> + .next = NEXT(NEXT_ENTRY(ACTION_NEXT)),
> + .call = parse_vc,
> + },
>
> /* Top-level command. */
> [ADD] = {
> diff --git a/doc/guides/testpmd_app_ug/testpmd_funcs.rst
> b/doc/guides/testpmd_app_ug/testpmd_funcs.rst
> index 330e34427d..c259c8239a 100644
> --- a/doc/guides/testpmd_app_ug/testpmd_funcs.rst
> +++ b/doc/guides/testpmd_app_ug/testpmd_funcs.rst
> @@ -4189,6 +4189,8 @@ This section lists supported actions and their
> attributes, if any.
>
> - ``ethdev_port_id {unsigned}``: ethdev port ID
>
> +- ``send_to_kernel``: send packets to kernel.
> +
> Destroying flow rules
> ~~~~~~~~~~~~~~~~~~~~~
>
> diff --git a/lib/ethdev/rte_flow.c b/lib/ethdev/rte_flow.c
> index 501be9d602..627c671ce4 100644
> --- a/lib/ethdev/rte_flow.c
> +++ b/lib/ethdev/rte_flow.c
> @@ -259,6 +259,7 @@ static const struct rte_flow_desc_data
> rte_flow_desc_action[] = {
> MK_FLOW_ACTION(CONNTRACK, sizeof(struct
> rte_flow_action_conntrack)),
> MK_FLOW_ACTION(PORT_REPRESENTOR, sizeof(struct
> rte_flow_action_ethdev)),
> MK_FLOW_ACTION(REPRESENTED_PORT, sizeof(struct
> rte_flow_action_ethdev)),
> + MK_FLOW_ACTION(SEND_TO_KERNEL, 0),
> };
>
> int
> diff --git a/lib/ethdev/rte_flow.h b/lib/ethdev/rte_flow.h
> index a79f1e7ef0..a82992a6ae 100644
> --- a/lib/ethdev/rte_flow.h
> +++ b/lib/ethdev/rte_flow.h
> @@ -2879,6 +2879,15 @@ enum rte_flow_action_type {
> * @see struct rte_flow_action_ethdev
> */
> RTE_FLOW_ACTION_TYPE_REPRESENTED_PORT,
> +
> + /*
> + * Send packets to the kernel, without going to userspace at all.
> + * The packets will be received by the kernel driver sharing
> + * the same device as the DPDK port.
> + *
> + * No associated configuration structure.
> + */
> + RTE_FLOW_ACTION_TYPE_SEND_TO_KERNEL,
> };
>
> /**
> --
> 2.27.0
Acked-by: Ori Kam <or...@nvidia.com>
Best,
Ori
