net/mlx5: E-Switch, Get counters for offloaded flows from callers

There's no real reason for the e-switch logic to manage the creation of
counters for offloaded flows. The API already has the directive for the
caller to denote they want to attach a counter to the created flow.
As such, we go and move the management of flow counters to the mlx5e
tc offload logic. This also lets us remove an inelegant interface where
the FS layer had to provide a way to retrieve a counter from a flow rule.

Signed-off-by: Mark Bloch <markb@mellanox.com>
Reviewed-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>

drivers/net/ethernet/mellanox/mlx5/core/en_tc.c

@@ -61,6 +61,7 @@ struct mlx5_nic_flow_attr {
 	u32 hairpin_tirn;
 	u8 match_level;
 	struct mlx5_flow_table	*hairpin_ft;
+	struct mlx5_fc		*counter;
 };
 
 #define MLX5E_TC_FLOW_BASE (MLX5E_TC_LAST_EXPORTED_BIT + 1)
@@ -721,6 +722,7 @@ mlx5e_tc_add_nic_flow(struct mlx5e_priv *priv,
 		dest[dest_ix].type = MLX5_FLOW_DESTINATION_TYPE_COUNTER;
 		dest[dest_ix].counter = counter;
 		dest_ix++;
+		attr->counter = counter;
 	}
 
 	if (attr->action & MLX5_FLOW_CONTEXT_ACTION_MOD_HDR) {
@@ -797,7 +799,7 @@ static void mlx5e_tc_del_nic_flow(struct mlx5e_priv *priv,
 	struct mlx5_nic_flow_attr *attr = flow->nic_attr;
 	struct mlx5_fc *counter = NULL;
 
-	counter = mlx5_flow_rule_counter(flow->rule[0]);
+	counter = attr->counter;
 	mlx5_del_flow_rules(flow->rule[0]);
 	mlx5_fc_destroy(priv->mdev, counter);
 
@@ -833,6 +835,7 @@ mlx5e_tc_add_fdb_flow(struct mlx5e_priv *priv,
 	struct mlx5_esw_flow_attr *attr = flow->esw_attr;
 	struct net_device *out_dev, *encap_dev = NULL;
 	struct mlx5_flow_handle *rule = NULL;
+	struct mlx5_fc *counter = NULL;
 	struct mlx5e_rep_priv *rpriv;
 	struct mlx5e_priv *out_priv;
 	int err;
@@ -868,6 +871,16 @@ mlx5e_tc_add_fdb_flow(struct mlx5e_priv *priv,
 		}
 	}
 
+	if (attr->action & MLX5_FLOW_CONTEXT_ACTION_COUNT) {
+		counter = mlx5_fc_create(esw->dev, true);
+		if (IS_ERR(counter)) {
+			rule = ERR_CAST(counter);
+			goto err_create_counter;
+		}
+
+		attr->counter = counter;
+	}
+
 	/* we get here if (1) there's no error (rule being null) or when
 	 * (2) there's an encap action and we're on -EAGAIN (no valid neigh)
 	 */
@@ -888,6 +901,8 @@ err_fwd_rule:
 	mlx5_eswitch_del_offloaded_rule(esw, rule, attr);
 	rule = flow->rule[1];
 err_add_rule:
+	mlx5_fc_destroy(esw->dev, counter);
+err_create_counter:
 	if (attr->action & MLX5_FLOW_CONTEXT_ACTION_MOD_HDR)
 		mlx5e_detach_mod_hdr(priv, flow);
 err_mod_hdr:
@@ -921,6 +936,9 @@ static void mlx5e_tc_del_fdb_flow(struct mlx5e_priv *priv,
 
 	if (attr->action & MLX5_FLOW_CONTEXT_ACTION_MOD_HDR)
 		mlx5e_detach_mod_hdr(priv, flow);
+
+	if (attr->action & MLX5_FLOW_CONTEXT_ACTION_COUNT)
+		mlx5_fc_destroy(esw->dev, attr->counter);
 }
 
 void mlx5e_tc_encap_flows_add(struct mlx5e_priv *priv,
@@ -992,6 +1010,14 @@ void mlx5e_tc_encap_flows_del(struct mlx5e_priv *priv,
 	}
 }
 
+static struct mlx5_fc *mlx5e_tc_get_counter(struct mlx5e_tc_flow *flow)
+{
+	if (flow->flags & MLX5E_TC_FLOW_ESWITCH)
+		return flow->esw_attr->counter;
+	else
+		return flow->nic_attr->counter;
+}
+
 void mlx5e_tc_update_neigh_used_value(struct mlx5e_neigh_hash_entry *nhe)
 {
 	struct mlx5e_neigh *m_neigh = &nhe->m_neigh;
@@ -1017,7 +1043,7 @@ void mlx5e_tc_update_neigh_used_value(struct mlx5e_neigh_hash_entry *nhe)
 			continue;
 		list_for_each_entry(flow, &e->flows, encap) {
 			if (flow->flags & MLX5E_TC_FLOW_OFFLOADED) {
-				counter = mlx5_flow_rule_counter(flow->rule[0]);
+				counter = mlx5e_tc_get_counter(flow);
 				mlx5_fc_query_cached(counter, &bytes, &packets, &lastuse);
 				if (time_after((unsigned long)lastuse, nhe->reported_lastuse)) {
 					neigh_used = true;
@@ -3019,7 +3045,7 @@ int mlx5e_stats_flower(struct mlx5e_priv *priv,
 	if (!(flow->flags & MLX5E_TC_FLOW_OFFLOADED))
 		return 0;
 
-	counter = mlx5_flow_rule_counter(flow->rule[0]);
+	counter = mlx5e_tc_get_counter(flow);
 	if (!counter)
 		return 0;
 

drivers/net/ethernet/mellanox/mlx5/core/eswitch.h

@@ -266,6 +266,7 @@ struct mlx5_esw_flow_attr {
 	u32	encap_id;
 	u32	mod_hdr_id;
 	u8	match_level;
+	struct mlx5_fc *counter;
 	struct mlx5e_tc_flow_parse_attr *parse_attr;
 };
 

drivers/net/ethernet/mellanox/mlx5/core/eswitch_offloads.c

@@ -51,7 +51,6 @@ mlx5_eswitch_add_offloaded_rule(struct mlx5_eswitch *esw,
 	struct mlx5_flow_destination dest[MLX5_MAX_FLOW_FWD_VPORTS + 1] = {};
 	struct mlx5_flow_act flow_act = {0};
 	struct mlx5_flow_table *ft = NULL;
-	struct mlx5_fc *counter = NULL;
 	struct mlx5_flow_handle *rule;
 	int j, i = 0;
 	void *misc;
@@ -91,13 +90,8 @@ mlx5_eswitch_add_offloaded_rule(struct mlx5_eswitch *esw,
 		}
 	}
 	if (flow_act.action & MLX5_FLOW_CONTEXT_ACTION_COUNT) {
-		counter = mlx5_fc_create(esw->dev, true);
-		if (IS_ERR(counter)) {
-			rule = ERR_CAST(counter);
-			goto err_counter_alloc;
-		}
 		dest[i].type = MLX5_FLOW_DESTINATION_TYPE_COUNTER;
-		dest[i].counter = counter;
+		dest[i].counter = attr->counter;
 		i++;
 	}
 
@@ -132,15 +126,11 @@ mlx5_eswitch_add_offloaded_rule(struct mlx5_eswitch *esw,
 
 	rule = mlx5_add_flow_rules(ft, spec, &flow_act, dest, i);
 	if (IS_ERR(rule))
-		goto err_add_rule;
+		goto out;
 	else
 		esw->offloads.num_flows++;
 
-	return rule;
-
-err_add_rule:
-	mlx5_fc_destroy(esw->dev, counter);
-err_counter_alloc:
+out:
 	return rule;
 }
 
@@ -200,11 +190,7 @@ mlx5_eswitch_del_offloaded_rule(struct mlx5_eswitch *esw,
 				struct mlx5_flow_handle *rule,
 				struct mlx5_esw_flow_attr *attr)
 {
-	struct mlx5_fc *counter = NULL;
-
-	counter = mlx5_flow_rule_counter(rule);
 	mlx5_del_flow_rules(rule);
-	mlx5_fc_destroy(esw->dev, counter);
 	esw->offloads.num_flows--;
 }
 

drivers/net/ethernet/mellanox/mlx5/core/fs_core.c

@@ -1474,21 +1474,6 @@ static struct mlx5_flow_handle *add_rule_fg(struct mlx5_flow_group *fg,
 	return handle;
 }
 
-struct mlx5_fc *mlx5_flow_rule_counter(struct mlx5_flow_handle *handle)
-{
-	struct mlx5_flow_rule *dst;
-	struct fs_fte *fte;
-
-	fs_get_obj(fte, handle->rule[0]->node.parent);
-
-	fs_for_each_dst(dst, fte) {
-		if (dst->dest_attr.type == MLX5_FLOW_DESTINATION_TYPE_COUNTER)
-			return dst->dest_attr.counter;
-	}
-
-	return NULL;
-}
-
 static bool counter_is_valid(struct mlx5_fc *counter, u32 action)
 {
 	if (!(action & MLX5_FLOW_CONTEXT_ACTION_COUNT))

include/linux/mlx5/fs.h

@@ -186,7 +186,6 @@ int mlx5_modify_rule_destination(struct mlx5_flow_handle *handler,
 				 struct mlx5_flow_destination *new_dest,
 				 struct mlx5_flow_destination *old_dest);
 
-struct mlx5_fc *mlx5_flow_rule_counter(struct mlx5_flow_handle *handler);
 struct mlx5_fc *mlx5_fc_create(struct mlx5_core_dev *dev, bool aging);
 void mlx5_fc_destroy(struct mlx5_core_dev *dev, struct mlx5_fc *counter);
 void mlx5_fc_query_cached(struct mlx5_fc *counter,