RE: [RFC PATCH v2] ethdev: advertise flow restore in mbuf

[Slava Ovsiienko <viacheslavo@nvidia.com>]

Hi,

My primary concern is vectorized rx_burst performance impact.
@Ali Alnubani, could we conduct the performance check, at least with SSE (x86) and Neon (BF2/3) archs?

With best regards,
Slava

> -----Original Message-----
> From: David Marchand <david.marchand@redhat.com>
> Sent: Thursday, June 15, 2023 4:47 PM
> To: dev@dpdk.org
> Cc: NBU-Contact-Thomas Monjalon (EXTERNAL) <thomas@monjalon.net>;
> i.maximets@ovn.org; Aman Singh <aman.deep.singh@intel.com>; Yuying
> Zhang <yuying.zhang@intel.com>; Matan Azrad <matan@nvidia.com>; Slava
> Ovsiienko <viacheslavo@nvidia.com>; Ori Kam <orika@nvidia.com>; Suanming
> Mou <suanmingm@nvidia.com>; David Christensen
> <drc@linux.vnet.ibm.com>; Ruifeng Wang <ruifeng.wang@arm.com>; Bruce
> Richardson <bruce.richardson@intel.com>; Konstantin Ananyev
> <konstantin.v.ananyev@yandex.ru>; Andrew Rybchenko
> <andrew.rybchenko@oktetlabs.ru>; Ferruh Yigit <ferruh.yigit@amd.com>
> Subject: [RFC PATCH v2] ethdev: advertise flow restore in mbuf
> 
> As reported by Ilya [1], unconditionally calling
> rte_flow_get_restore_info() impacts an application performance for drivers
> that do not provide this ops.
> It could also impact processing of packets that require no call to
> rte_flow_get_restore_info() at all.
> 
> Register a dynamic mbuf flag when an application negotiates tunnel metadata
> delivery (calling rte_eth_rx_metadata_negotiate() with
> RTE_ETH_RX_METADATA_TUNNEL_ID).
> 
> Drivers then advertise that metadata can be extracted by setting this dynamic
> flag in each mbuf.
> 
> The application then calls rte_flow_get_restore_info() only when required.
> 
> Link: http://inbox.dpdk.org/dev/5248c2ca-f2a6-3fb0-38b8-
> 7f659bfa40de@ovn.org/
> Signed-off-by: David Marchand <david.marchand@redhat.com>
> ---
> Changes since RFC v1:
> - rebased,
> - updated vectorized datapath functions for net/mlx5,
> - moved dynamic flag register to rte_eth_rx_metadata_negotiate() and
>   hid rte_flow_restore_info_dynflag_register() into ethdev internals,
> 
> ---
>  app/test-pmd/util.c                      |  9 +++--
>  drivers/net/mlx5/mlx5.c                  |  2 +
>  drivers/net/mlx5/mlx5.h                  |  5 ++-
>  drivers/net/mlx5/mlx5_flow.c             | 47 +++++++++++++++++++++---
>  drivers/net/mlx5/mlx5_rx.c               |  2 +-
>  drivers/net/mlx5/mlx5_rx.h               |  1 +
>  drivers/net/mlx5/mlx5_rxtx_vec_altivec.h | 16 ++++----
>  drivers/net/mlx5/mlx5_rxtx_vec_neon.h    |  6 +--
>  drivers/net/mlx5/mlx5_rxtx_vec_sse.h     |  6 +--
>  drivers/net/mlx5/mlx5_trigger.c          |  4 +-
>  drivers/net/sfc/sfc_dp.c                 | 14 +------
>  lib/ethdev/rte_ethdev.c                  |  5 +++
>  lib/ethdev/rte_flow.c                    | 29 +++++++++++++++
>  lib/ethdev/rte_flow.h                    | 18 ++++++++-
>  lib/ethdev/rte_flow_driver.h             |  6 +++
>  lib/ethdev/version.map                   |  1 +
>  16 files changed, 130 insertions(+), 41 deletions(-)
> 
> diff --git a/app/test-pmd/util.c b/app/test-pmd/util.c index
> f9df5f69ef..5aa69ed545 100644
> --- a/app/test-pmd/util.c
> +++ b/app/test-pmd/util.c
> @@ -88,18 +88,20 @@ dump_pkt_burst(uint16_t port_id, uint16_t queue,
> struct rte_mbuf *pkts[],
>  	char print_buf[MAX_STRING_LEN];
>  	size_t buf_size = MAX_STRING_LEN;
>  	size_t cur_len = 0;
> +	uint64_t restore_info_dynflag;
> 
>  	if (!nb_pkts)
>  		return;
> +	restore_info_dynflag = rte_flow_restore_info_dynflag();
>  	MKDUMPSTR(print_buf, buf_size, cur_len,
>  		  "port %u/queue %u: %s %u packets\n", port_id, queue,
>  		  is_rx ? "received" : "sent", (unsigned int) nb_pkts);
>  	for (i = 0; i < nb_pkts; i++) {
> -		int ret;
>  		struct rte_flow_error error;
>  		struct rte_flow_restore_info info = { 0, };
> 
>  		mb = pkts[i];
> +		ol_flags = mb->ol_flags;
>  		if (rxq_share > 0)
>  			MKDUMPSTR(print_buf, buf_size, cur_len, "port %u, ",
>  				  mb->port);
> @@ -107,8 +109,8 @@ dump_pkt_burst(uint16_t port_id, uint16_t queue,
> struct rte_mbuf *pkts[],
>  		eth_type = RTE_BE_TO_CPU_16(eth_hdr->ether_type);
>  		packet_type = mb->packet_type;
>  		is_encapsulation = RTE_ETH_IS_TUNNEL_PKT(packet_type);
> -		ret = rte_flow_get_restore_info(port_id, mb, &info, &error);
> -		if (!ret) {
> +		if ((ol_flags & restore_info_dynflag) != 0 &&
> +				rte_flow_get_restore_info(port_id, mb, &info,
> &error) == 0) {
>  			MKDUMPSTR(print_buf, buf_size, cur_len,
>  				  "restore info:");
>  			if (info.flags & RTE_FLOW_RESTORE_INFO_TUNNEL) {
> @@ -153,7 +155,6 @@ dump_pkt_burst(uint16_t port_id, uint16_t queue,
> struct rte_mbuf *pkts[],
>  			  " - pool=%s - type=0x%04x - length=%u -
> nb_segs=%d",
>  			  mb->pool->name, eth_type, (unsigned int) mb-
> >pkt_len,
>  			  (int)mb->nb_segs);
> -		ol_flags = mb->ol_flags;
>  		if (ol_flags & RTE_MBUF_F_RX_RSS_HASH) {
>  			MKDUMPSTR(print_buf, buf_size, cur_len,
>  				  " - RSS hash=0x%x",
> diff --git a/drivers/net/mlx5/mlx5.c b/drivers/net/mlx5/mlx5.c index
> a75fa1b7f0..58fde3af22 100644
> --- a/drivers/net/mlx5/mlx5.c
> +++ b/drivers/net/mlx5/mlx5.c
> @@ -2347,6 +2347,7 @@ const struct eth_dev_ops mlx5_dev_ops = {
>  	.get_monitor_addr = mlx5_get_monitor_addr,
>  	.count_aggr_ports = mlx5_count_aggr_ports,
>  	.map_aggr_tx_affinity = mlx5_map_aggr_tx_affinity,
> +	.rx_metadata_negotiate = mlx5_flow_rx_metadata_negotiate,
>  };
> 
>  /* Available operations from secondary process. */ @@ -2372,6 +2373,7 @@
> const struct eth_dev_ops mlx5_dev_sec_ops = {
>  	.get_module_eeprom = mlx5_get_module_eeprom,
>  	.count_aggr_ports = mlx5_count_aggr_ports,
>  	.map_aggr_tx_affinity = mlx5_map_aggr_tx_affinity,
> +	.rx_metadata_negotiate = mlx5_flow_rx_metadata_negotiate,
>  };
> 
>  /* Available operations in flow isolated mode. */ diff --git
> a/drivers/net/mlx5/mlx5.h b/drivers/net/mlx5/mlx5.h index
> 021049ad2b..bf464613f0 100644
> --- a/drivers/net/mlx5/mlx5.h
> +++ b/drivers/net/mlx5/mlx5.h
> @@ -1745,6 +1745,7 @@ struct mlx5_priv {
>  	unsigned int lb_used:1; /* Loopback queue is referred to. */
>  	uint32_t mark_enabled:1; /* If mark action is enabled on rxqs. */
>  	uint32_t num_lag_ports:4; /* Number of ports can be bonded. */
> +	uint32_t tunnel_enabled:1; /* If tunnel offloading is enabled on rxqs.
> +*/
>  	uint16_t domain_id; /* Switch domain identifier. */
>  	uint16_t vport_id; /* Associated VF vport index (if any). */
>  	uint32_t vport_meta_tag; /* Used for vport index match ove VF LAG.
> */ @@ -2154,7 +2155,9 @@ int mlx5_flow_query_counter(struct rte_eth_dev
> *dev, struct rte_flow *flow,  int mlx5_flow_dev_dump_ipool(struct
> rte_eth_dev *dev, struct rte_flow *flow,
>  		FILE *file, struct rte_flow_error *error);  #endif -void
> mlx5_flow_rxq_dynf_metadata_set(struct rte_eth_dev *dev);
> +int mlx5_flow_rx_metadata_negotiate(struct rte_eth_dev *dev,
> +	uint64_t *features);
> +void mlx5_flow_rxq_dynf_set(struct rte_eth_dev *dev);
>  int mlx5_flow_get_aged_flows(struct rte_eth_dev *dev, void **contexts,
>  			uint32_t nb_contexts, struct rte_flow_error *error);
> int mlx5_validate_action_ct(struct rte_eth_dev *dev, diff --git
> a/drivers/net/mlx5/mlx5_flow.c b/drivers/net/mlx5/mlx5_flow.c index
> eb1d7a6be2..19e567401b 100644
> --- a/drivers/net/mlx5/mlx5_flow.c
> +++ b/drivers/net/mlx5/mlx5_flow.c
> @@ -1796,6 +1796,38 @@ flow_rxq_flags_clear(struct rte_eth_dev *dev)
>  	priv->sh->shared_mark_enabled = 0;
>  }
> 
> +static uint64_t mlx5_restore_info_dynflag;
> +
> +int
> +mlx5_flow_rx_metadata_negotiate(struct rte_eth_dev *dev, uint64_t
> +*features) {
> +	struct mlx5_priv *priv = dev->data->dev_private;
> +	uint64_t supported = 0;
> +
> +	if (!is_tunnel_offload_active(dev)) {
> +		supported |= RTE_ETH_RX_METADATA_USER_FLAG;
> +		supported |= RTE_ETH_RX_METADATA_USER_MARK;
> +		if ((*features & RTE_ETH_RX_METADATA_TUNNEL_ID) != 0) {
> +			DRV_LOG(DEBUG,
> +				"tunnel offload was not activated, consider
> setting dv_xmeta_en=%d",
> +				MLX5_XMETA_MODE_MISS_INFO);
> +		}
> +	} else {
> +		supported |= RTE_ETH_RX_METADATA_TUNNEL_ID;
> +		if ((*features & RTE_ETH_RX_METADATA_TUNNEL_ID) != 0 &&
> +				mlx5_restore_info_dynflag == 0)
> +			mlx5_restore_info_dynflag =
> rte_flow_restore_info_dynflag();
> +	}
> +
> +	if (((*features & supported) & RTE_ETH_RX_METADATA_TUNNEL_ID)
> != 0)
> +		priv->tunnel_enabled = 1;
> +	else
> +		priv->tunnel_enabled = 0;
> +
> +	*features &= supported;
> +	return 0;
> +}
> +
>  /**
>   * Set the Rx queue dynamic metadata (mask and offset) for a flow
>   *
> @@ -1803,11 +1835,15 @@ flow_rxq_flags_clear(struct rte_eth_dev *dev)
>   *   Pointer to the Ethernet device structure.
>   */
>  void
> -mlx5_flow_rxq_dynf_metadata_set(struct rte_eth_dev *dev)
> +mlx5_flow_rxq_dynf_set(struct rte_eth_dev *dev)
>  {
>  	struct mlx5_priv *priv = dev->data->dev_private;
> +	uint64_t mark_flag = RTE_MBUF_F_RX_FDIR_ID;
>  	unsigned int i;
> 
> +	if (priv->tunnel_enabled)
> +		mark_flag |= mlx5_restore_info_dynflag;
> +
>  	for (i = 0; i != priv->rxqs_n; ++i) {
>  		struct mlx5_rxq_priv *rxq = mlx5_rxq_get(dev, i);
>  		struct mlx5_rxq_data *data;
> @@ -1826,6 +1862,7 @@ mlx5_flow_rxq_dynf_metadata_set(struct
> rte_eth_dev *dev)
>  			data->flow_meta_offset =
> rte_flow_dynf_metadata_offs;
>  			data->flow_meta_port_mask = priv->sh-
> >dv_meta_mask;
>  		}
> +		data->mark_flag = mark_flag;
>  	}
>  }
> 
> @@ -11560,12 +11597,10 @@ mlx5_flow_tunnel_get_restore_info(struct
> rte_eth_dev *dev,
>  	uint64_t ol_flags = m->ol_flags;
>  	const struct mlx5_flow_tbl_data_entry *tble;
>  	const uint64_t mask = RTE_MBUF_F_RX_FDIR |
> RTE_MBUF_F_RX_FDIR_ID;
> +	struct mlx5_priv *priv = dev->data->dev_private;
> 
> -	if (!is_tunnel_offload_active(dev)) {
> -		info->flags = 0;
> -		return 0;
> -	}
> -
> +	if (priv->tunnel_enabled == 0)
> +		goto err;
>  	if ((ol_flags & mask) != mask)
>  		goto err;
>  	tble = tunnel_mark_decode(dev, m->hash.fdir.hi); diff --git
> a/drivers/net/mlx5/mlx5_rx.c b/drivers/net/mlx5/mlx5_rx.c index
> a2be523e9e..71c4638251 100644
> --- a/drivers/net/mlx5/mlx5_rx.c
> +++ b/drivers/net/mlx5/mlx5_rx.c
> @@ -857,7 +857,7 @@ rxq_cq_to_mbuf(struct mlx5_rxq_data *rxq, struct
> rte_mbuf *pkt,
>  		if (MLX5_FLOW_MARK_IS_VALID(mark)) {
>  			pkt->ol_flags |= RTE_MBUF_F_RX_FDIR;
>  			if (mark != RTE_BE32(MLX5_FLOW_MARK_DEFAULT)) {
> -				pkt->ol_flags |= RTE_MBUF_F_RX_FDIR_ID;
> +				pkt->ol_flags |= rxq->mark_flag;
>  				pkt->hash.fdir.hi =
> mlx5_flow_mark_get(mark);
>  			}
>  		}
> diff --git a/drivers/net/mlx5/mlx5_rx.h b/drivers/net/mlx5/mlx5_rx.h index
> 52c35c83f8..3514edd84e 100644
> --- a/drivers/net/mlx5/mlx5_rx.h
> +++ b/drivers/net/mlx5/mlx5_rx.h
> @@ -136,6 +136,7 @@ struct mlx5_rxq_data {
>  	struct mlx5_uar_data uar_data; /* CQ doorbell. */
>  	uint32_t cqn; /* CQ number. */
>  	uint8_t cq_arm_sn; /* CQ arm seq number. */
> +	uint64_t mark_flag; /* ol_flags to set with marks. */
>  	uint32_t tunnel; /* Tunnel information. */
>  	int timestamp_offset; /* Dynamic mbuf field for timestamp. */
>  	uint64_t timestamp_rx_flag; /* Dynamic mbuf flag for timestamp. */
> diff --git a/drivers/net/mlx5/mlx5_rxtx_vec_altivec.h
> b/drivers/net/mlx5/mlx5_rxtx_vec_altivec.h
> index 14ffff26f4..4d0d05c376 100644
> --- a/drivers/net/mlx5/mlx5_rxtx_vec_altivec.h
> +++ b/drivers/net/mlx5/mlx5_rxtx_vec_altivec.h
> @@ -296,15 +296,15 @@ rxq_cq_decompress_v(struct mlx5_rxq_data *rxq,
> volatile struct mlx5_cqe *cq,
>  				const __vector unsigned char fdir_all_flags =
>  					(__vector unsigned char)
>  					(__vector unsigned int){
> -					RTE_MBUF_F_RX_FDIR |
> RTE_MBUF_F_RX_FDIR_ID,
> -					RTE_MBUF_F_RX_FDIR |
> RTE_MBUF_F_RX_FDIR_ID,
> -					RTE_MBUF_F_RX_FDIR |
> RTE_MBUF_F_RX_FDIR_ID,
> -					RTE_MBUF_F_RX_FDIR |
> RTE_MBUF_F_RX_FDIR_ID};
> +					RTE_MBUF_F_RX_FDIR | rxq-
> >mark_flag,
> +					RTE_MBUF_F_RX_FDIR | rxq-
> >mark_flag,
> +					RTE_MBUF_F_RX_FDIR | rxq-
> >mark_flag,
> +					RTE_MBUF_F_RX_FDIR | rxq-
> >mark_flag};
>  				__vector unsigned char fdir_id_flags =
>  					(__vector unsigned char)
>  					(__vector unsigned int){
> -					RTE_MBUF_F_RX_FDIR_ID,
> RTE_MBUF_F_RX_FDIR_ID,
> -					RTE_MBUF_F_RX_FDIR_ID,
> RTE_MBUF_F_RX_FDIR_ID};
> +					rxq->mark_flag, rxq->mark_flag,
> +					rxq->mark_flag, rxq->mark_flag};
>  				/* Extract flow_tag field. */
>  				__vector unsigned char ftag0 =
> vec_perm(mcqe1,
>  							zero,
> flow_mark_shuf);
> @@ -632,8 +632,8 @@ rxq_cq_to_ptype_oflags_v(struct mlx5_rxq_data *rxq,
>  			RTE_MBUF_F_RX_FDIR, RTE_MBUF_F_RX_FDIR};
>  		__vector unsigned char fdir_id_flags =
>  			(__vector unsigned char)(__vector unsigned int){
> -			RTE_MBUF_F_RX_FDIR_ID, RTE_MBUF_F_RX_FDIR_ID,
> -			RTE_MBUF_F_RX_FDIR_ID, RTE_MBUF_F_RX_FDIR_ID};
> +			rxq->mark_flag, rxq->mark_flag,
> +			rxq->mark_flag, rxq->mark_flag};
>  		__vector unsigned char flow_tag, invalid_mask;
> 
>  		flow_tag = (__vector unsigned char)
> diff --git a/drivers/net/mlx5/mlx5_rxtx_vec_neon.h
> b/drivers/net/mlx5/mlx5_rxtx_vec_neon.h
> index 75e8ed7e5a..91c85bec6d 100644
> --- a/drivers/net/mlx5/mlx5_rxtx_vec_neon.h
> +++ b/drivers/net/mlx5/mlx5_rxtx_vec_neon.h
> @@ -231,9 +231,9 @@ rxq_cq_decompress_v(struct mlx5_rxq_data *rxq,
> volatile struct mlx5_cqe *cq,
>  					vdupq_n_u32(RTE_MBUF_F_RX_FDIR);
>  				const uint32x4_t fdir_all_flags =
>  					vdupq_n_u32(RTE_MBUF_F_RX_FDIR
> |
> -						    RTE_MBUF_F_RX_FDIR_ID);
> +						    rxq->mark_flag);
>  				uint32x4_t fdir_id_flags =
> -
> 	vdupq_n_u32(RTE_MBUF_F_RX_FDIR_ID);
> +					vdupq_n_u32(rxq->mark_flag);
>  				uint32x4_t invalid_mask, ftag;
> 
>  				__asm__ volatile
> @@ -446,7 +446,7 @@ rxq_cq_to_ptype_oflags_v(struct mlx5_rxq_data *rxq,
>  	if (rxq->mark) {
>  		const uint32x4_t ft_def =
> vdupq_n_u32(MLX5_FLOW_MARK_DEFAULT);
>  		const uint32x4_t fdir_flags =
> vdupq_n_u32(RTE_MBUF_F_RX_FDIR);
> -		uint32x4_t fdir_id_flags =
> vdupq_n_u32(RTE_MBUF_F_RX_FDIR_ID);
> +		uint32x4_t fdir_id_flags = vdupq_n_u32(rxq->mark_flag);
>  		uint32x4_t invalid_mask;
> 
>  		/* Check if flow tag is non-zero then set
> RTE_MBUF_F_RX_FDIR. */ diff --git a/drivers/net/mlx5/mlx5_rxtx_vec_sse.h
> b/drivers/net/mlx5/mlx5_rxtx_vec_sse.h
> index b282f8b8e6..0766952255 100644
> --- a/drivers/net/mlx5/mlx5_rxtx_vec_sse.h
> +++ b/drivers/net/mlx5/mlx5_rxtx_vec_sse.h
> @@ -214,9 +214,9 @@ rxq_cq_decompress_v(struct mlx5_rxq_data *rxq,
> volatile struct mlx5_cqe *cq,
> 
> 	_mm_set1_epi32(RTE_MBUF_F_RX_FDIR);
>  				const __m128i fdir_all_flags =
> 
> 	_mm_set1_epi32(RTE_MBUF_F_RX_FDIR |
> -
> RTE_MBUF_F_RX_FDIR_ID);
> +						       rxq->mark_flag);
>  				__m128i fdir_id_flags =
> -
> 	_mm_set1_epi32(RTE_MBUF_F_RX_FDIR_ID);
> +					_mm_set1_epi32(rxq->mark_flag);
> 
>  				/* Extract flow_tag field. */
>  				__m128i ftag0 =
> @@ -442,7 +442,7 @@ rxq_cq_to_ptype_oflags_v(struct mlx5_rxq_data *rxq,
> __m128i cqes[4],
>  	if (rxq->mark) {
>  		const __m128i pinfo_ft_mask = _mm_set1_epi32(0xffffff00);
>  		const __m128i fdir_flags =
> _mm_set1_epi32(RTE_MBUF_F_RX_FDIR);
> -		__m128i fdir_id_flags =
> _mm_set1_epi32(RTE_MBUF_F_RX_FDIR_ID);
> +		__m128i fdir_id_flags = _mm_set1_epi32(rxq->mark_flag);
>  		__m128i flow_tag, invalid_mask;
> 
>  		flow_tag = _mm_and_si128(pinfo, pinfo_ft_mask); diff --git
> a/drivers/net/mlx5/mlx5_trigger.c b/drivers/net/mlx5/mlx5_trigger.c index
> bbaa7d2aa0..7bdb897612 100644
> --- a/drivers/net/mlx5/mlx5_trigger.c
> +++ b/drivers/net/mlx5/mlx5_trigger.c
> @@ -1282,8 +1282,8 @@ mlx5_dev_start(struct rte_eth_dev *dev)
>  			dev->data->port_id);
>  		goto error;
>  	}
> -	/* Set a mask and offset of dynamic metadata flows into Rx queues.
> */
> -	mlx5_flow_rxq_dynf_metadata_set(dev);
> +	/* Set dynamic fields and flags into Rx queues. */
> +	mlx5_flow_rxq_dynf_set(dev);
>  	/* Set flags and context to convert Rx timestamps. */
>  	mlx5_rxq_timestamp_set(dev);
>  	/* Set a mask and offset of scheduling on timestamp into Tx queues.
> */ diff --git a/drivers/net/sfc/sfc_dp.c b/drivers/net/sfc/sfc_dp.c index
> 9f2093b353..2b0a1d749d 100644
> --- a/drivers/net/sfc/sfc_dp.c
> +++ b/drivers/net/sfc/sfc_dp.c
> @@ -11,6 +11,7 @@
>  #include <string.h>
>  #include <errno.h>
> 
> +#include <rte_ethdev.h>
>  #include <rte_log.h>
>  #include <rte_mbuf_dyn.h>
> 
> @@ -135,12 +136,8 @@ sfc_dp_ft_ctx_id_register(void)
>  		.size = sizeof(uint8_t),
>  		.align = __alignof__(uint8_t),
>  	};
> -	static const struct rte_mbuf_dynflag ft_ctx_id_valid = {
> -		.name = "rte_net_sfc_dynflag_ft_ctx_id_valid",
> -	};
> 
>  	int field_offset;
> -	int flag;
> 
>  	SFC_GENERIC_LOG(INFO, "%s() entry", __func__);
> 
> @@ -156,15 +153,8 @@ sfc_dp_ft_ctx_id_register(void)
>  		return -1;
>  	}
> 
> -	flag = rte_mbuf_dynflag_register(&ft_ctx_id_valid);
> -	if (flag < 0) {
> -		SFC_GENERIC_LOG(ERR, "%s() failed to register ft_ctx_id
> dynflag",
> -				__func__);
> -		return -1;
> -	}
> -
> +	sfc_dp_ft_ctx_id_valid = rte_flow_restore_info_dynflag();
>  	sfc_dp_ft_ctx_id_offset = field_offset;
> -	sfc_dp_ft_ctx_id_valid = UINT64_C(1) << flag;
> 
>  	SFC_GENERIC_LOG(INFO, "%s() done", __func__);
> 
> diff --git a/lib/ethdev/rte_ethdev.c b/lib/ethdev/rte_ethdev.c index
> 7317015895..2884bc4f45 100644
> --- a/lib/ethdev/rte_ethdev.c
> +++ b/lib/ethdev/rte_ethdev.c
> @@ -30,6 +30,7 @@
>  #include "rte_ethdev.h"
>  #include "rte_ethdev_trace_fp.h"
>  #include "ethdev_driver.h"
> +#include "rte_flow_driver.h"
>  #include "ethdev_profile.h"
>  #include "ethdev_private.h"
>  #include "ethdev_trace.h"
> @@ -6441,6 +6442,10 @@ rte_eth_rx_metadata_negotiate(uint16_t port_id,
> uint64_t *features)
>  		return -EINVAL;
>  	}
> 
> +	if ((*features & RTE_ETH_RX_METADATA_TUNNEL_ID) != 0 &&
> +			rte_flow_restore_info_dynflag_register(NULL) < 0)
> +		*features &= ~RTE_ETH_RX_METADATA_TUNNEL_ID;
> +
>  	if (*dev->dev_ops->rx_metadata_negotiate == NULL)
>  		return -ENOTSUP;
>  	ret = eth_err(port_id,
> diff --git a/lib/ethdev/rte_flow.c b/lib/ethdev/rte_flow.c index
> d41963b42e..5731b90642 100644
> --- a/lib/ethdev/rte_flow.c
> +++ b/lib/ethdev/rte_flow.c
> @@ -1441,6 +1441,35 @@ rte_flow_get_restore_info(uint16_t port_id,
>  				  NULL, rte_strerror(ENOTSUP));
>  }
> 
> +static struct {
> +	const struct rte_mbuf_dynflag desc;
> +	uint64_t value;
> +} flow_restore_info_dynflag = {
> +	.desc = { .name = "RTE_MBUF_F_RX_RESTORE_INFO", }, };
> +
> +uint64_t
> +rte_flow_restore_info_dynflag(void)
> +{
> +	return flow_restore_info_dynflag.value; }
> +
> +int
> +rte_flow_restore_info_dynflag_register(uint64_t *flag) {
> +	if (flow_restore_info_dynflag.value == 0) {
> +		int offset =
> +rte_mbuf_dynflag_register(&flow_restore_info_dynflag.desc);
> +
> +		if (offset < 0)
> +			return -1;
> +		flow_restore_info_dynflag.value = RTE_BIT64(offset);
> +	}
> +	if (*flag)
> +		*flag = rte_flow_restore_info_dynflag();
> +
> +	return 0;
> +}
> +
>  int
>  rte_flow_tunnel_action_decap_release(uint16_t port_id,
>  				     struct rte_flow_action *actions, diff --git
> a/lib/ethdev/rte_flow.h b/lib/ethdev/rte_flow.h index
> dec454275f..261d95378b 100644
> --- a/lib/ethdev/rte_flow.h
> +++ b/lib/ethdev/rte_flow.h
> @@ -5128,7 +5128,23 @@ rte_flow_tunnel_match(uint16_t port_id,
>  		      struct rte_flow_error *error);
> 
>  /**
> - * Populate the current packet processing state, if exists, for the given mbuf.
> + * On reception of a mbuf from HW, a call to
> +rte_flow_get_restore_info() may be
> + * required to retrieve some metadata.
> + * This function returns the associated mbuf ol_flags.
> + *
> + * Note: the dynamic flag is registered during a call to
> + * rte_eth_rx_metadata_negotiate() with
> RTE_ETH_RX_METADATA_TUNNEL_ID.
> + *
> + * @return
> + *   The offload flag indicating rte_flow_get_restore_info() must be called.
> + */
> +__rte_experimental
> +uint64_t
> +rte_flow_restore_info_dynflag(void);
> +
> +/**
> + * If a mbuf contains the rte_flow_restore_info_dynflag() flag in
> +ol_flags,
> + * populate the current packet processing state.
>   *
>   * One should negotiate tunnel metadata delivery from the NIC to the HW.
>   * @see rte_eth_rx_metadata_negotiate() diff --git
> a/lib/ethdev/rte_flow_driver.h b/lib/ethdev/rte_flow_driver.h index
> 356b60f523..a28448fc3b 100644
> --- a/lib/ethdev/rte_flow_driver.h
> +++ b/lib/ethdev/rte_flow_driver.h
> @@ -376,6 +376,12 @@ struct rte_flow_ops {  const struct rte_flow_ops *
> rte_flow_ops_get(uint16_t port_id, struct rte_flow_error *error);
> 
> +/**
> + * Register mbuf dynamic flag for rte_flow_get_restore_info.
> + */
> +int
> +rte_flow_restore_info_dynflag_register(uint64_t *flag);
> +
>  #ifdef __cplusplus
>  }
>  #endif
> diff --git a/lib/ethdev/version.map b/lib/ethdev/version.map index
> 1a33d72668..0031be32bf 100644
> --- a/lib/ethdev/version.map
> +++ b/lib/ethdev/version.map
> @@ -311,6 +311,7 @@ EXPERIMENTAL {
>  	rte_flow_async_action_list_handle_destroy;
>  	rte_flow_async_action_list_handle_query_update;
>  	rte_flow_async_actions_update;
> +	rte_flow_restore_info_dynflag;
>  };
> 
>  INTERNAL {
> --
> 2.40.1