[dpdk-dev] [PATCH 06/28] net/mlx5: check conditions to enable LRO

[Matan Azrad <matan@mellanox.com>]

From: Dekel Peled <dekelp@mellanox.com>

Use DevX API to read device LRO capabilities.
Check if LRO is supported and can be enabled.
Check if MPRQ is supported and can be used.
Enable MPRQ for LRO use if not enabled by user.
Added note for mlx5_mprq_enabled(), to emphasize that LRO
enables MPRQ.
Disable CQE compression and CRC stripping if LRO is enabled.

Signed-off-by: Dekel Peled <dekelp@mellanox.com>
Acked-by: Matan Azrad <matan@mellanox.com>
---
 drivers/net/mlx5/mlx5.c        | 49 +++++++++++++++++++++++++++---------------
 drivers/net/mlx5/mlx5_ethdev.c | 12 +++++++++++
 drivers/net/mlx5/mlx5_rxq.c    | 14 +++++++++++-
 3 files changed, 57 insertions(+), 18 deletions(-)

diff --git a/drivers/net/mlx5/mlx5.c b/drivers/net/mlx5/mlx5.c
index 792324f..8d0ebeb 100644
--- a/drivers/net/mlx5/mlx5.c
+++ b/drivers/net/mlx5/mlx5.c
@@ -1683,6 +1683,38 @@ struct mlx5_dev_spawn_data {
 	} else if (config.cqe_pad) {
 		DRV_LOG(INFO, "Rx CQE padding is enabled");
 	}
+	if (config.devx) {
+		priv->counter_fallback = 0;
+		err = mlx5_devx_cmd_query_hca_attr(sh->ctx, &config.hca_attr);
+		if (err) {
+			err = -err;
+			goto error;
+		}
+		if (!config.hca_attr.flow_counters_dump)
+			priv->counter_fallback = 1;
+#ifndef HAVE_IBV_DEVX_ASYNC
+		priv->counter_fallback = 1;
+#endif
+		if (priv->counter_fallback)
+			DRV_LOG(INFO, "Use fall-back DV counter management\n");
+		/* Check for LRO support. */
+		if (config.dest_tir && mprq && config.hca_attr.lro_cap) {
+			/* TBD check tunnel lro caps. */
+			config.lro.supported = config.hca_attr.lro_cap;
+			DRV_LOG(DEBUG, "Device supports LRO");
+			/*
+			 * If LRO timeout is not configured by application,
+			 * use the minimal supported value.
+			 */
+			if (!config.lro.timeout)
+				config.lro.timeout =
+				config.hca_attr.lro_timer_supported_periods[0];
+			DRV_LOG(DEBUG, "LRO session timeout set to %d usec",
+				config.lro.timeout);
+			config.mprq.enabled = 1;
+			DRV_LOG(DEBUG, "Enable MPRQ for LRO use");
+		}
+	}
 	if (config.mprq.enabled && mprq) {
 		if (config.mprq.stride_num_n > mprq_max_stride_num_n ||
 		    config.mprq.stride_num_n < mprq_min_stride_num_n) {
@@ -1783,23 +1815,6 @@ struct mlx5_dev_spawn_data {
 	 * Verbs context returned by ibv_open_device().
 	 */
 	mlx5_link_update(eth_dev, 0);
-#ifdef HAVE_IBV_DEVX_OBJ
-	if (config.devx) {
-		priv->counter_fallback = 0;
-		err = mlx5_devx_cmd_query_hca_attr(sh->ctx, &config.hca_attr);
-		if (err) {
-			err = -err;
-			goto error;
-		}
-		if (!config.hca_attr.flow_counters_dump)
-			priv->counter_fallback = 1;
-#ifndef HAVE_IBV_DEVX_ASYNC
-		priv->counter_fallback = 1;
-#endif
-		if (priv->counter_fallback)
-			DRV_LOG(INFO, "Use fall-back DV counter management\n");
-	}
-#endif
 #ifdef HAVE_MLX5DV_DR_ESWITCH
 	if (!(config.hca_attr.eswitch_manager && config.dv_flow_en &&
 	      (switch_info->representor || switch_info->master)))
diff --git a/drivers/net/mlx5/mlx5_ethdev.c b/drivers/net/mlx5/mlx5_ethdev.c
index 1125e16..72416db 100644
--- a/drivers/net/mlx5/mlx5_ethdev.c
+++ b/drivers/net/mlx5/mlx5_ethdev.c
@@ -482,6 +482,7 @@ struct ethtool_link_settings {
 	const uint8_t use_app_rss_key =
 		!!dev->data->dev_conf.rx_adv_conf.rss_conf.rss_key;
 	int ret = 0;
+	unsigned int lro_on = mlx5_lro_on(dev);
 
 	if (use_app_rss_key &&
 	    (dev->data->dev_conf.rx_adv_conf.rss_conf.rss_key_len !=
@@ -525,6 +526,12 @@ struct ethtool_link_settings {
 			dev->data->port_id, priv->rxqs_n, rxqs_n);
 		priv->rxqs_n = rxqs_n;
 		/*
+		 * WHen using LRO, MPRQ is implicitly enabled.
+		 * Adjust threshold value to ensure MPRQ can be enabled.
+		 */
+		if (lro_on && priv->config.mprq.min_rxqs_num > priv->rxqs_n)
+			priv->config.mprq.min_rxqs_num = priv->rxqs_n;
+		/*
 		 * If the requested number of RX queues is not a power of two,
 		 * use the maximum indirection table size for better balancing.
 		 * The result is always rounded to the next power of two.
@@ -546,6 +553,11 @@ struct ethtool_link_settings {
 				j = 0;
 		}
 	}
+	if (lro_on && priv->config.cqe_comp) {
+		/* CQE compressing is not supported for LRO CQEs. */
+		DRV_LOG(WARNING, "Rx CQE compression isn't supported with LRO");
+		priv->config.cqe_comp = 0;
+	}
 	ret = mlx5_proc_priv_init(dev);
 	if (ret)
 		return ret;
diff --git a/drivers/net/mlx5/mlx5_rxq.c b/drivers/net/mlx5/mlx5_rxq.c
index e68de50..8567ee5 100644
--- a/drivers/net/mlx5/mlx5_rxq.c
+++ b/drivers/net/mlx5/mlx5_rxq.c
@@ -93,6 +93,7 @@
 
 /**
  * Check whether Multi-Packet RQ is enabled for the device.
+ * MPRQ can be enabled explicitly, or implicitly by enabling LRO.
  *
  * @param dev
  *   Pointer to Ethernet device.
@@ -1431,7 +1432,18 @@ struct mlx5_rxq_ctrl *
 	tmpl->rxq.crc_present = 0;
 	if (offloads & DEV_RX_OFFLOAD_KEEP_CRC) {
 		if (config->hw_fcs_strip) {
-			tmpl->rxq.crc_present = 1;
+			/*
+			 * RQs used for LRO-enabled TIRs should not be
+			 * configured to scatter the FCS.
+			 */
+			if (mlx5_lro_on(dev))
+				DRV_LOG(WARNING,
+					"port %u CRC stripping has been "
+					"disabled but will still be performed "
+					"by hardware, because LRO is enabled",
+					dev->data->port_id);
+			else
+				tmpl->rxq.crc_present = 1;
 		} else {
 			DRV_LOG(WARNING,
 				"port %u CRC stripping has been disabled but will"
-- 
1.8.3.1