net/i40e: fix statistics

1. Fix the lldp stop condition check - for firmware
versions 6.01(for X710)/3.33(for X722) or later we need stop the lldp
2. deferred stats reset in dev_init to avoid some noise be counted.
3. Document known issue for tx bytes decreasing due to link status change

Fixes: 044846f071cc ("net/i40e: stop LLDP before setting local LLDP MIB")
Cc: stable@dpdk.org
Signed-off-by: Chenmin Sun <chenmin.sun@intel.com>
Acked-by: Qi Zhang <qi.z.zhang@intel.com>

diff --git a/doc/guides/nics/i40e.rst b/doc/guides/nics/i40e.rst
index 53bc024..9680a92 100644 (file)
--- a/doc/guides/nics/i40e.rst
+++ b/doc/guides/nics/i40e.rst
@@ -704,3 +704,9 @@ See :numref:`figure_intel_perf_test_setup` for the performance test setup.
    * Start creating a stream on packet generator.
 
    * Set the Ethernet II type to 0x0800.
+
+Tx bytes affected by the link status change
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+For firmware versions prior to 6.01 for X710 series and 3.33 for X722 series, the tx_bytes statistics data is affected by
+the link down event. Each time the link status changes to down, the tx_bytes decreases 110 bytes.

diff --git a/drivers/net/i40e/i40e_ethdev.c b/drivers/net/i40e/i40e_ethdev.c
index f97cd53..dca61f0 100644 (file)
--- a/drivers/net/i40e/i40e_ethdev.c
+++ b/drivers/net/i40e/i40e_ethdev.c
@@ -1493,9 +1493,6 @@ eth_i40e_dev_init(struct rte_eth_dev *dev, void *init_params __rte_unused)
                goto err_setup_pf_switch;
        }
 
-       /* reset all stats of the device, including pf and main vsi */
-       i40e_dev_stats_reset(dev);
-
        vsi = pf->main_vsi;
 
        /* Disable double vlan by default */
@@ -1590,6 +1587,9 @@ eth_i40e_dev_init(struct rte_eth_dev *dev, void *init_params __rte_unused)
        memset(&pf->rss_info, 0,
                sizeof(struct i40e_rte_flow_rss_conf));
 
+       /* reset all stats of the device, including pf and main vsi */
+       i40e_dev_stats_reset(dev);
+
        return 0;
 
 err_init_fdir_filter_list:
@@ -3460,6 +3460,31 @@ i40e_fw_version_get(struct rte_eth_dev *dev, char *fw_version, size_t fw_size)
                return 0;
 }
 
+/*
+ * When using NVM 6.01(for X710 XL710 XXV710)/3.33(for X722) or later,
+ * the Rx data path does not hang if the FW LLDP is stopped.
+ * return true if lldp need to stop
+ * return false if we cannot disable the LLDP to avoid Rx data path blocking.
+ */
+static bool
+i40e_need_stop_lldp(struct rte_eth_dev *dev)
+{
+       double nvm_ver;
+       char ver_str[64] = {0};
+       struct i40e_hw *hw = I40E_DEV_PRIVATE_TO_HW(dev->data->dev_private);
+
+       i40e_fw_version_get(dev, ver_str, 64);
+       nvm_ver = atof(ver_str);
+       if ((hw->mac.type == I40E_MAC_X722 ||
+            hw->mac.type == I40E_MAC_X722_VF) &&
+            ((uint32_t)(nvm_ver * 1000) >= (uint32_t)(3.33 * 1000)))
+               return true;
+       else if ((uint32_t)(nvm_ver * 1000) >= (uint32_t)(6.01 * 1000))
+               return true;
+
+       return false;
+}
+
 static void
 i40e_dev_info_get(struct rte_eth_dev *dev, struct rte_eth_dev_info *dev_info)
 {
@@ -11427,11 +11452,7 @@ i40e_dcb_init_configure(struct rte_eth_dev *dev, bool sw_dcb)
         * LLDP MIB change event.
         */
        if (sw_dcb == TRUE) {
-               /* When using NVM 6.01 or later, the RX data path does
-                * not hang if the FW LLDP is stopped.
-                */
-               if (((hw->nvm.version >> 12) & 0xf) >= 6 &&
-                   ((hw->nvm.version >> 4) & 0xff) >= 1) {
+               if (i40e_need_stop_lldp(dev)) {
                        ret = i40e_aq_stop_lldp(hw, TRUE, NULL);
                        if (ret != I40E_SUCCESS)
                                PMD_INIT_LOG(DEBUG, "Failed to stop lldp");