net/mlx5e: HTB, Fix inconsistencies with QoS SQs number

When creating a new HTB class while the interface is down,
the variable that follows the number of QoS SQs (htb_max_qos_sqs)
may not be consistent with the number of HTB classes.

Previously, we compared these two values to ensure that
the node_qid is lower than the number of QoS SQs, and we
allocated stats for that SQ when they are equal.

Change the check to compare the node_qid with the current
number of leaf nodes and fix the checking conditions to
ensure allocation of stats_list and stats for each node.

Fixes: 214baf22 ("net/mlx5e: Support HTB offload")
Signed-off-by: Carolina Jubran <cjubran@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Reviewed-by: Dragos Tatulea <dtatulea@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Link: https://lore.kernel.org/r/20240409190820.227554-9-tariqt@nvidia.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/ethernet/mellanox/mlx5/core/en/qos.c

@@ -83,24 +83,25 @@ int mlx5e_open_qos_sq(struct mlx5e_priv *priv, struct mlx5e_channels *chs,
 
 	txq_ix = mlx5e_qid_from_qos(chs, node_qid);
 
-	WARN_ON(node_qid > priv->htb_max_qos_sqs);
-	if (node_qid == priv->htb_max_qos_sqs) {
-		struct mlx5e_sq_stats *stats, **stats_list = NULL;
+	WARN_ON(node_qid >= mlx5e_htb_cur_leaf_nodes(priv->htb));
+	if (!priv->htb_qos_sq_stats) {
+		struct mlx5e_sq_stats **stats_list;
 
-		if (priv->htb_max_qos_sqs == 0) {
 		stats_list = kvcalloc(mlx5e_qos_max_leaf_nodes(priv->mdev),
-					      sizeof(*stats_list),
-					      GFP_KERNEL);
+				      sizeof(*stats_list), GFP_KERNEL);
 		if (!stats_list)
 			return -ENOMEM;
+
+		WRITE_ONCE(priv->htb_qos_sq_stats, stats_list);
 	}
+
+	if (!priv->htb_qos_sq_stats[node_qid]) {
+		struct mlx5e_sq_stats *stats;
+
 		stats = kzalloc(sizeof(*stats), GFP_KERNEL);
-		if (!stats) {
-			kvfree(stats_list);
+		if (!stats)
 			return -ENOMEM;
-		}
-		if (stats_list)
-			WRITE_ONCE(priv->htb_qos_sq_stats, stats_list);
+
 		WRITE_ONCE(priv->htb_qos_sq_stats[node_qid], stats);
 		/* Order htb_max_qos_sqs increment after writing the array pointer.
 		 * Pairs with smp_load_acquire in en_stats.c.