flow_offload: add statistics retrieval infrastructure and use it

This patch provides the flow_stats structure that acts as container for
tc_cls_flower_offload, then we can use to restore the statistics on the
existing TC actions. Hence, tcf_exts_stats_update() is not used from
drivers anymore.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/broadcom/bnxt/bnxt_tc.c

@@ -1396,8 +1396,8 @@ static int bnxt_tc_get_flow_stats(struct bnxt *bp,
 	lastused = flow->lastused;
 	spin_unlock(&flow->stats_lock);
 
-	tcf_exts_stats_update(tc_flow_cmd->exts, stats.bytes, stats.packets,
-			      lastused);
+	flow_stats_update(&tc_flow_cmd->stats, stats.bytes, stats.packets,
+			  lastused);
 	return 0;
 }
 

drivers/net/ethernet/chelsio/cxgb4/cxgb4_tc_flower.c

@@ -807,9 +807,9 @@ int cxgb4_tc_flower_stats(struct net_device *dev,
 	if (ofld_stats->packet_count != packets) {
 		if (ofld_stats->prev_packet_count != packets)
 			ofld_stats->last_used = jiffies;
-		tcf_exts_stats_update(cls->exts, bytes - ofld_stats->byte_count,
-				      packets - ofld_stats->packet_count,
-				      ofld_stats->last_used);
+		flow_stats_update(&cls->stats, bytes - ofld_stats->byte_count,
+				  packets - ofld_stats->packet_count,
+				  ofld_stats->last_used);
 
 		ofld_stats->packet_count = packets;
 		ofld_stats->byte_count = bytes;

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

@@ -3071,7 +3071,7 @@ int mlx5e_stats_flower(struct net_device *dev, struct mlx5e_priv *priv,
 	mlx5_devcom_release_peer_data(devcom, MLX5_DEVCOM_ESW_OFFLOADS);
 
 out:
-	tcf_exts_stats_update(f->exts, bytes, packets, lastuse);
+	flow_stats_update(&f->stats, bytes, packets, lastuse);
 
 	return 0;
 }

drivers/net/ethernet/mellanox/mlxsw/spectrum_flower.c

@@ -460,7 +460,7 @@ int mlxsw_sp_flower_stats(struct mlxsw_sp *mlxsw_sp,
 	if (err)
 		goto err_rule_get_stats;
 
-	tcf_exts_stats_update(f->exts, bytes, packets, lastuse);
+	flow_stats_update(&f->stats, bytes, packets, lastuse);
 
 	mlxsw_sp_acl_ruleset_put(mlxsw_sp, ruleset);
 	return 0;

drivers/net/ethernet/netronome/nfp/flower/offload.c

@@ -554,9 +554,8 @@ nfp_flower_get_stats(struct nfp_app *app, struct net_device *netdev,
 	ctx_id = be32_to_cpu(nfp_flow->meta.host_ctx_id);
 
 	spin_lock_bh(&priv->stats_lock);
-	tcf_exts_stats_update(flow->exts, priv->stats[ctx_id].bytes,
-			      priv->stats[ctx_id].pkts,
-			      priv->stats[ctx_id].used);
+	flow_stats_update(&flow->stats, priv->stats[ctx_id].bytes,
+			  priv->stats[ctx_id].pkts, priv->stats[ctx_id].used);
 
 	priv->stats[ctx_id].pkts = 0;
 	priv->stats[ctx_id].bytes = 0;

include/net/flow_offload.h

@@ -179,4 +179,18 @@ static inline bool flow_rule_match_key(const struct flow_rule *rule,
 	return dissector_uses_key(rule->match.dissector, key);
 }
 
+struct flow_stats {
+	u64	pkts;
+	u64	bytes;
+	u64	lastused;
+};
+
+static inline void flow_stats_update(struct flow_stats *flow_stats,
+				     u64 bytes, u64 pkts, u64 lastused)
+{
+	flow_stats->pkts	= pkts;
+	flow_stats->bytes	= bytes;
+	flow_stats->lastused	= lastused;
+}
+
 #endif /* _NET_FLOW_OFFLOAD_H */

include/net/pkt_cls.h

@@ -765,6 +765,7 @@ struct tc_cls_flower_offload {
 	enum tc_fl_command command;
 	unsigned long cookie;
 	struct flow_rule *rule;
+	struct flow_stats stats;
 	struct tcf_exts *exts;
 	u32 classid;
 };

net/sched/cls_flower.c

@@ -429,6 +429,10 @@ static void fl_hw_update_stats(struct tcf_proto *tp, struct cls_fl_filter *f)
 	cls_flower.classid = f->res.classid;
 
 	tc_setup_cb_call(block, TC_SETUP_CLSFLOWER, &cls_flower, false);
+
+	tcf_exts_stats_update(&f->exts, cls_flower.stats.bytes,
+			      cls_flower.stats.pkts,
+			      cls_flower.stats.lastused);
 }
 
 static bool __fl_delete(struct tcf_proto *tp, struct cls_fl_filter *f,