iavf: Fix TC config comparison with existing adapter TC config

stable inclusion
from stable-v6.6.30
commit 2f7cc2dfc15999e8878b7689d172053b57fb3ebb
bugzilla: https://gitee.com/openeuler/kernel/issues/I9MPZ8

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=2f7cc2dfc15999e8878b7689d172053b57fb3ebb

--------------------------------

[ Upstream commit 54976cf58d6168b8d15cebb395069f23b2f34b31 ]

Same number of TCs doesn't imply that underlying TC configs are
same. The config could be different due to difference in number
of queues in each TC. Add utility function to determine if TC
configs are same.

Fixes: d5b33d0 ("i40evf: add ndo_setup_tc callback to i40evf")
Signed-off-by: Sudheer Mogilappagari <[email protected]>
Tested-by: Mineri Bhange <[email protected]> (A Contingent Worker at Intel)
Signed-off-by: Tony Nguyen <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
Signed-off-by: ZhangPeng <[email protected]>

Author: msudheer337

drivers/net/ethernet/intel/iavf/iavf_main.c

@@ -3574,6 +3574,34 @@ static void iavf_del_all_cloud_filters(struct iavf_adapter *adapter)
 	spin_unlock_bh(&adapter->cloud_filter_list_lock);
 }
 
+/**
+ * iavf_is_tc_config_same - Compare the mqprio TC config with the
+ * TC config already configured on this adapter.
+ * @adapter: board private structure
+ * @mqprio_qopt: TC config received from kernel.
+ *
+ * This function compares the TC config received from the kernel
+ * with the config already configured on the adapter.
+ *
+ * Return: True if configuration is same, false otherwise.
+ **/
+static bool iavf_is_tc_config_same(struct iavf_adapter *adapter,
+				   struct tc_mqprio_qopt *mqprio_qopt)
+{
+	struct virtchnl_channel_info *ch = &adapter->ch_config.ch_info[0];
+	int i;
+
+	if (adapter->num_tc != mqprio_qopt->num_tc)
+		return false;
+
+	for (i = 0; i < adapter->num_tc; i++) {
+		if (ch[i].count != mqprio_qopt->count[i] ||
+		    ch[i].offset != mqprio_qopt->offset[i])
+			return false;
+	}
+	return true;
+}
+
 /**
  * __iavf_setup_tc - configure multiple traffic classes
  * @netdev: network interface device structure
@@ -3631,7 +3659,7 @@ static int __iavf_setup_tc(struct net_device *netdev, void *type_data)
 		if (ret)
 			return ret;
 		/* Return if same TC config is requested */
-		if (adapter->num_tc == num_tc)
+		if (iavf_is_tc_config_same(adapter, &mqprio_qopt->qopt))
 			return 0;
 		adapter->num_tc = num_tc;