mlxsw: spectrum_qdisc: Extract a common leaf unoffload function

When the RED Qdisc is unoffloaded, it needs to reduce the reported backlog
by the amount that is in the HW, so that only the SW backlog is contained
in the counter. The same thing will need to be done by TBF, and likely any
other leaf Qdisc as well.

Extract a helper mlxsw_sp_qdisc_leaf_unoffload() and call it from
mlxsw_sp_qdisc_red_unoffload().
Signed-off-by: NPetr Machata <petrm@mellanox.com>
Signed-off-by: NIdo Schimmel <idosch@mellanox.com>
Acked-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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

@@ -421,19 +421,28 @@ mlxsw_sp_qdisc_red_replace(struct mlxsw_sp_port *mlxsw_sp_port,
 }
 
 static void
-mlxsw_sp_qdisc_red_unoffload(struct mlxsw_sp_port *mlxsw_sp_port,
-			     struct mlxsw_sp_qdisc *mlxsw_sp_qdisc,
-			     void *params)
+mlxsw_sp_qdisc_leaf_unoffload(struct mlxsw_sp_port *mlxsw_sp_port,
+			      struct mlxsw_sp_qdisc *mlxsw_sp_qdisc,
+			      struct gnet_stats_queue *qstats)
 {
-	struct tc_red_qopt_offload_params *p = params;
 	u64 backlog;
 
 	backlog = mlxsw_sp_cells_bytes(mlxsw_sp_port->mlxsw_sp,
 				       mlxsw_sp_qdisc->stats_base.backlog);
-	p->qstats->backlog -= backlog;
+	qstats->backlog -= backlog;
 	mlxsw_sp_qdisc->stats_base.backlog = 0;
 }
 
+static void
+mlxsw_sp_qdisc_red_unoffload(struct mlxsw_sp_port *mlxsw_sp_port,
+			     struct mlxsw_sp_qdisc *mlxsw_sp_qdisc,
+			     void *params)
+{
+	struct tc_red_qopt_offload_params *p = params;
+
+	mlxsw_sp_qdisc_leaf_unoffload(mlxsw_sp_port, mlxsw_sp_qdisc, p->qstats);
+}
+
 static int
 mlxsw_sp_qdisc_get_red_xstats(struct mlxsw_sp_port *mlxsw_sp_port,
 			      struct mlxsw_sp_qdisc *mlxsw_sp_qdisc,