[dpdk-stable] [PATCH v3] net/i40e: fix incorrect hash look up table

[Shougang Wang]

The hash look up table (LUT) is managed by global register but it is not
initialized when RSS is disabled. Once user wants to enable RSS during
runtime, the LUT will not be initialized.
This patch fixes the issue by initializing the LUT whether RSS enabled
or not.

Fixes: feaae285b342 ("net/i40e: support hash configuration in RSS flow")
Cc: stable at dpdk.org

Signed-off-by: Shougang Wang <shougangx.wang at intel.com>
---
v3:
-Updated the time of initializing the look up table
---
 drivers/net/i40e/i40e_ethdev.c | 85 ++++++++++++++++++++--------------
 1 file changed, 49 insertions(+), 36 deletions(-)

diff --git a/drivers/net/i40e/i40e_ethdev.c b/drivers/net/i40e/i40e_ethdev.c
index 05d5f2861..e35590d96 100644
--- a/drivers/net/i40e/i40e_ethdev.c
+++ b/drivers/net/i40e/i40e_ethdev.c
@@ -8984,42 +8984,7 @@ i40e_pf_calc_configured_queues_num(struct i40e_pf *pf)
 static int
 i40e_pf_config_rss(struct i40e_pf *pf)
 {
-	struct i40e_hw *hw = I40E_PF_TO_HW(pf);
 	struct rte_eth_rss_conf rss_conf;
-	uint32_t i, lut = 0;
-	uint16_t j, num;
-
-	/*
-	 * If both VMDQ and RSS enabled, not all of PF queues are configured.
-	 * It's necessary to calculate the actual PF queues that are configured.
-	 */
-	if (pf->dev_data->dev_conf.rxmode.mq_mode & ETH_MQ_RX_VMDQ_FLAG)
-		num = i40e_pf_calc_configured_queues_num(pf);
-	else
-		num = pf->dev_data->nb_rx_queues;
-
-	num = RTE_MIN(num, I40E_MAX_Q_PER_TC);
-	PMD_INIT_LOG(INFO, "Max of contiguous %u PF queues are configured",
-			num);
-
-	if (num == 0) {
-		PMD_INIT_LOG(ERR,
-			"No PF queues are configured to enable RSS for port %u",
-			pf->dev_data->port_id);
-		return -ENOTSUP;
-	}
-
-	if (pf->adapter->rss_reta_updated == 0) {
-		for (i = 0, j = 0; i < hw->func_caps.rss_table_size; i++, j++) {
-			if (j == num)
-				j = 0;
-			lut = (lut << 8) | (j & ((0x1 <<
-				hw->func_caps.rss_table_entry_width) - 1));
-			if ((i & 3) == 3)
-				I40E_WRITE_REG(hw, I40E_PFQF_HLUT(i >> 2),
-					       rte_bswap32(lut));
-		}
-	}
 
 	rss_conf = pf->dev_data->dev_conf.rx_adv_conf.rss_conf;
 	if ((rss_conf.rss_hf & pf->adapter->flow_types_mask) == 0) {
@@ -9195,12 +9160,60 @@ i40e_tunnel_filter_handle(struct rte_eth_dev *dev,
 	return ret;
 }
 
+/* Initialize the hash look up table */
+static int
+i40e_pf_init_rss_lut(struct i40e_pf *pf)
+{
+	struct i40e_hw *hw = I40E_PF_TO_HW(pf);
+	uint32_t lut = 0;
+	uint16_t j, num;
+	uint32_t i;
+
+	/* If both VMDQ and RSS enabled, not all of PF queues are configured.
+	 * It's necessary to calculate the actual PF queues that are configured.
+	 */
+	if (pf->dev_data->dev_conf.rxmode.mq_mode & ETH_MQ_RX_VMDQ_FLAG)
+		num = i40e_pf_calc_configured_queues_num(pf);
+	else
+		num = pf->dev_data->nb_rx_queues;
+
+	num = RTE_MIN(num, I40E_MAX_Q_PER_TC);
+	PMD_INIT_LOG(INFO, "Max of contiguous %u PF queues are configured",
+		     num);
+
+	if (num == 0) {
+		PMD_INIT_LOG(ERR,
+			"No PF queues are configured to enable RSS for port %u",
+			pf->dev_data->port_id);
+		return -ENOTSUP;
+	}
+
+	if (pf->adapter->rss_reta_updated == 0) {
+		for (i = 0, j = 0; i < hw->func_caps.rss_table_size; i++, j++) {
+			if (j == num)
+				j = 0;
+			lut = (lut << 8) | (j & ((0x1 <<
+				hw->func_caps.rss_table_entry_width) - 1));
+			if ((i & 3) == 3)
+				I40E_WRITE_REG(hw, I40E_PFQF_HLUT(i >> 2),
+					       rte_bswap32(lut));
+		}
+	}
+
+	return 0;
+}
+
 static int
 i40e_pf_config_mq_rx(struct i40e_pf *pf)
 {
-	int ret = 0;
+	int ret;
 	enum rte_eth_rx_mq_mode mq_mode = pf->dev_data->dev_conf.rxmode.mq_mode;
 
+	/* Initialize hash look up table */
+	ret = i40e_pf_init_rss_lut(pf);
+	if (ret)
+		return ret;
+
 	/* RSS setup */
 	if (mq_mode & ETH_MQ_RX_RSS_FLAG)
 		ret = i40e_pf_config_rss(pf);
-- 
2.17.1