[dpdk-dev] [PATCH v5 1/3] net/ena: indicate Rx RSS hash presence

[Michal Krawczyk]

To make it possible to the app to determine if the hash was calculated
for the packet or not, the PKT_RX_RSS_HASH should be set in the mbuf's
ol_flags.

As the PMD wasn't setting that, the application couldn't check if there
is a hash in a proper way.

The hash is valid only if it's UDP or TCP and the IP packet wasn't
fragmented.

Fixes: e5df9f33db00 ("net/ena: fix passing RSS hash to mbuf")
Cc: stable at dpdk.org

Signed-off-by: Michal Krawczyk <mk at semihalf.com>
Reviewed-by: Igor Chauskin <igorch at amazon.com>
Reviewed-by: Amit Bernstein <amitbern at amazon.com>
---
v5:
* Announce Rx RSS hash support in the dev_info->rx_offload_capa.

v4:
* Add release notes.
* Always announce DEV_RX_OFFLOAD_RSS_HASH if RSS is enabled.

 doc/guides/rel_notes/release_21_05.rst |  1 +
 drivers/net/ena/ena_ethdev.c           | 13 +++++++++++--
 2 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/doc/guides/rel_notes/release_21_05.rst b/doc/guides/rel_notes/release_21_05.rst
index 4e669d3108..0466415112 100644
--- a/doc/guides/rel_notes/release_21_05.rst
+++ b/doc/guides/rel_notes/release_21_05.rst
@@ -120,6 +120,7 @@ New Features
   * Updated ena_com (HAL) to the latest version.
   * Fixed bugs when requesting large LLQ headers using the devargs.
   * Fixed bug when the default ring size was set.
+  * Added indication of the RSS hash presence in the mbuf.
 
 * **Updated Arkville PMD driver.**
 
diff --git a/drivers/net/ena/ena_ethdev.c b/drivers/net/ena/ena_ethdev.c
index 54d5e756cb..fb2b19cfdb 100644
--- a/drivers/net/ena/ena_ethdev.c
+++ b/drivers/net/ena/ena_ethdev.c
@@ -51,6 +51,8 @@
 
 #define ENA_MIN_RING_DESC	128
 
+#define ENA_PTYPE_HAS_HASH	(RTE_PTYPE_L4_TCP | RTE_PTYPE_L4_UDP)
+
 enum ethtool_stringset {
 	ETH_SS_TEST             = 0,
 	ETH_SS_STATS,
@@ -314,6 +316,11 @@ static inline void ena_rx_mbuf_prepare(struct rte_mbuf *mbuf,
 		else
 			ol_flags |= PKT_RX_L4_CKSUM_GOOD;
 
+	if (likely((packet_type & ENA_PTYPE_HAS_HASH) && !ena_rx_ctx->frag)) {
+		ol_flags |= PKT_RX_RSS_HASH;
+		mbuf->hash.rss = ena_rx_ctx->hash;
+	}
+
 	mbuf->ol_flags = ol_flags;
 	mbuf->packet_type = packet_type;
 }
@@ -1954,6 +1961,9 @@ static int ena_dev_configure(struct rte_eth_dev *dev)
 
 	adapter->state = ENA_ADAPTER_STATE_CONFIG;
 
+	if (dev->data->dev_conf.rxmode.mq_mode & ETH_MQ_RX_RSS_FLAG)
+		dev->data->dev_conf.rxmode.offloads |= DEV_RX_OFFLOAD_RSS_HASH;
+
 	adapter->tx_selected_offloads = dev->data->dev_conf.txmode.offloads;
 	adapter->rx_selected_offloads = dev->data->dev_conf.rxmode.offloads;
 	return 0;
@@ -2030,6 +2040,7 @@ static int ena_infos_get(struct rte_eth_dev *dev,
 
 	/* Inform framework about available features */
 	dev_info->rx_offload_capa = rx_feat;
+	dev_info->rx_offload_capa |= DEV_RX_OFFLOAD_RSS_HASH;
 	dev_info->rx_queue_offload_capa = rx_feat;
 	dev_info->tx_offload_capa = tx_feat;
 	dev_info->tx_queue_offload_capa = tx_feat;
@@ -2242,8 +2253,6 @@ static uint16_t eth_ena_recv_pkts(void *rx_queue, struct rte_mbuf **rx_pkts,
 			++rx_ring->rx_stats.bad_csum;
 		}
 
-		mbuf->hash.rss = ena_rx_ctx.hash;
-
 		rx_pkts[completed] = mbuf;
 		rx_ring->rx_stats.bytes += mbuf->pkt_len;
 	}
-- 
2.25.1