[PATCH 7/8] ethdev: check RSS availability

[David Marchand]

Add RSS capability check in rte_eth_dev_configure() using
dev_info.flow_type_rss_offloads.
When zero, reject Rx modes with RTE_ETH_MQ_RX_RSS_FLAG.
Remove redundant RSS checks from drivers.

Signed-off-by: David Marchand <david.marchand at redhat.com>
---
 devtools/check-doc-vs-code.sh          | 14 +++++++++++++-
 doc/guides/rel_notes/release_26_11.rst |  2 ++
 drivers/net/intel/cpfl/cpfl_ethdev.c   |  3 ---
 drivers/net/nfp/nfp_net_common.c       |  7 -------
 drivers/net/octeontx/octeontx_ethdev.c |  3 +--
 drivers/net/sfc/sfc_rx.c               |  9 +--------
 lib/ethdev/rte_ethdev.c                |  8 ++++++++
 7 files changed, 25 insertions(+), 21 deletions(-)

diff --git a/devtools/check-doc-vs-code.sh b/devtools/check-doc-vs-code.sh
index 81c9713f5a..da8398bfa4 100755
--- a/devtools/check-doc-vs-code.sh
+++ b/devtools/check-doc-vs-code.sh
@@ -89,6 +89,18 @@ check_mq_caps() # <driver>
 		fi
 	fi
 
+	if all_docs_agree $1 "RSS hash"; then
+		if has_doc_feature "$doc" "RSS hash"; then
+			git grep -qE 'flow_type_rss_offloads[[:space:]]*\|?=' -- "$code" ||
+				error "RSS documented but flow_type_rss_offloads not set for $1"
+		else
+			! git grep -qE 'flow_type_rss_offloads[[:space:]]*\|?=' -- "$code" ||
+				error "flow_type_rss_offloads set but RSS not documented for $1"
+			! git grep -qE 'RTE_ETH_MQ_RX.*RSS' -- "$code" ||
+				error "RSS mq_mode referenced but RSS not documented for $1"
+		fi
+	fi
+
 	if all_docs_agree $1 "VMDq"; then
 		if has_doc_feature "$doc" "VMDq"; then
 			git grep -qE 'max_vmdq_pools[[:space:]]*=' -- "$code" ||
@@ -131,7 +143,7 @@ if has_code_change 'RTE_FLOW_.*_TYPE_' ||
 		check_rte_flow $driver
 	done
 fi
-if has_code_change 'get_dcb_info\|max_vmdq_pools\|RTE_ETH_MQ_.*DCB\|RTE_ETH_MQ_.*VMDQ' ||
+if has_code_change 'get_dcb_info\|flow_type_rss_offloads\|max_vmdq_pools\|RTE_ETH_MQ_' ||
 		has_file_change 'doc/guides/nics/features'; then
 	for driver in $(changed_net_drivers); do
 		check_mq_caps $driver
diff --git a/doc/guides/rel_notes/release_26_11.rst b/doc/guides/rel_notes/release_26_11.rst
index 9341769c32..caffd2a611 100644
--- a/doc/guides/rel_notes/release_26_11.rst
+++ b/doc/guides/rel_notes/release_26_11.rst
@@ -428,6 +428,8 @@ API Changes
 
   * DCB modes (Rx ``RTE_ETH_MQ_RX_DCB_FLAG``, Tx ``RTE_ETH_MQ_TX_DCB``/``RTE_ETH_MQ_TX_VMDQ_DCB``)
     are rejected if the driver has no ``get_dcb_info`` callback.
+  * RSS mode (Rx ``RTE_ETH_MQ_RX_RSS_FLAG``) is rejected if the driver reports no
+    ``flow_type_rss_offloads``.
   * VMDq modes (Rx ``RTE_ETH_MQ_RX_VMDQ_FLAG``,
     Tx ``RTE_ETH_MQ_TX_VMDQ_DCB``/``RTE_ETH_MQ_TX_VMDQ_ONLY``) are rejected
     if the driver reports no VMDq pool.
diff --git a/drivers/net/intel/cpfl/cpfl_ethdev.c b/drivers/net/intel/cpfl/cpfl_ethdev.c
index 0863043a2e..f425181bf2 100644
--- a/drivers/net/intel/cpfl/cpfl_ethdev.c
+++ b/drivers/net/intel/cpfl/cpfl_ethdev.c
@@ -752,9 +752,6 @@ cpfl_dev_configure(struct rte_eth_dev *dev)
 			PMD_INIT_LOG(ERR, "Failed to init rss");
 			return ret;
 		}
-	} else if (conf->rxmode.mq_mode == RTE_ETH_MQ_RX_RSS) {
-		PMD_INIT_LOG(ERR, "RSS is not supported.");
-		return -ENOTSUP;
 	}
 
 	vport->max_pkt_len =
diff --git a/drivers/net/nfp/nfp_net_common.c b/drivers/net/nfp/nfp_net_common.c
index afa0bc0faf..f9957086d2 100644
--- a/drivers/net/nfp/nfp_net_common.c
+++ b/drivers/net/nfp/nfp_net_common.c
@@ -373,13 +373,6 @@ nfp_net_configure(struct rte_eth_dev *dev)
 		return -EINVAL;
 	}
 
-	/* Checking RX mode */
-	if ((rxmode->mq_mode & RTE_ETH_MQ_RX_RSS_FLAG) != 0 &&
-			(hw->super.cap & NFP_NET_CFG_CTRL_RSS_ANY) == 0) {
-		PMD_DRV_LOG(ERR, "RSS not supported.");
-		return -EINVAL;
-	}
-
 	/* Checking MTU set */
 	if (rxmode->mtu > hw->max_mtu + NFP_ETH_OVERHEAD) {
 		PMD_DRV_LOG(ERR, "MTU (%u) larger than the maximum possible frame size (%u).",
diff --git a/drivers/net/octeontx/octeontx_ethdev.c b/drivers/net/octeontx/octeontx_ethdev.c
index e173535d29..e0df23049c 100644
--- a/drivers/net/octeontx/octeontx_ethdev.c
+++ b/drivers/net/octeontx/octeontx_ethdev.c
@@ -499,8 +499,7 @@ octeontx_dev_configure(struct rte_eth_dev *dev)
 		return -EINVAL;
 	}
 
-	if (rxmode->mq_mode != RTE_ETH_MQ_RX_NONE &&
-		rxmode->mq_mode != RTE_ETH_MQ_RX_RSS) {
+	if (rxmode->mq_mode != RTE_ETH_MQ_RX_NONE) {
 		octeontx_log_err("unsupported rx qmode %d", rxmode->mq_mode);
 		return -EINVAL;
 	}
diff --git a/drivers/net/sfc/sfc_rx.c b/drivers/net/sfc/sfc_rx.c
index 1d4101b9e9..aa59931f06 100644
--- a/drivers/net/sfc/sfc_rx.c
+++ b/drivers/net/sfc/sfc_rx.c
@@ -1668,21 +1668,14 @@ sfc_rx_qinit_info(struct sfc_adapter *sa, sfc_sw_index_t sw_index,
 static int
 sfc_rx_check_mode(struct sfc_adapter *sa, struct rte_eth_rxmode *rxmode)
 {
-	struct sfc_adapter_shared * const sas = sfc_sa2shared(sa);
 	uint64_t offloads_supported = sfc_rx_get_dev_offload_caps(sa) |
 				      sfc_rx_get_queue_offload_caps(sa);
-	struct sfc_rss *rss = &sas->rss;
 	int rc = 0;
 
 	switch (rxmode->mq_mode) {
 	case RTE_ETH_MQ_RX_NONE:
-		/* No special checks are required */
-		break;
 	case RTE_ETH_MQ_RX_RSS:
-		if (rss->context_type == EFX_RX_SCALE_UNAVAILABLE) {
-			sfc_err(sa, "RSS is not available");
-			rc = EINVAL;
-		}
+		/* No special checks are required */
 		break;
 	default:
 		sfc_err(sa, "Rx multi-queue mode %u not supported",
diff --git a/lib/ethdev/rte_ethdev.c b/lib/ethdev/rte_ethdev.c
index 39a895c9e4..44b20697ae 100644
--- a/lib/ethdev/rte_ethdev.c
+++ b/lib/ethdev/rte_ethdev.c
@@ -1526,6 +1526,14 @@ rte_eth_dev_configure(uint16_t port_id, uint16_t nb_rx_q, uint16_t nb_tx_q,
 		goto rollback;
 	}
 
+	if (dev_info.flow_type_rss_offloads == 0 &&
+			(dev_conf->rxmode.mq_mode & RTE_ETH_MQ_RX_RSS_FLAG) != 0) {
+		RTE_ETHDEV_LOG_LINE(ERR, "Ethdev port_id=%u does not support RSS rx mode",
+			port_id);
+		ret = -EINVAL;
+		goto rollback;
+	}
+
 	dev->data->dev_conf.rx_adv_conf.rss_conf.rss_hf =
 		rte_eth_rss_hf_refine(dev_conf->rx_adv_conf.rss_conf.rss_hf);
 
-- 
2.54.0