mlxsw: spectrum: Track MTU in struct mlxsw_sp_hdroom

MTU influences sizes of auto-allocated buffers. Make it a part of port
buffer configuration and have __mlxsw_sp_port_headroom_set() take it from
there, instead of as an argument.
Signed-off-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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

@@ -627,7 +627,7 @@ static void mlxsw_sp_pg_buf_pack(char *pbmc_pl, int index, u16 size, u16 thres,
 }
 
 static u16 mlxsw_sp_hdroom_buf_delay_get(const struct mlxsw_sp *mlxsw_sp,
-					 const struct mlxsw_sp_hdroom *hdroom, int mtu)
+					 const struct mlxsw_sp_hdroom *hdroom)
 {
 	u16 delay_cells;
 
@@ -641,12 +641,12 @@ static u16 mlxsw_sp_hdroom_buf_delay_get(const struct mlxsw_sp *mlxsw_sp,
 	 * Another MTU is added in case the transmitting host already started
 	 * transmitting a maximum length frame when the PFC packet was received.
 	 */
-	return 2 * delay_cells + mlxsw_sp_bytes_cells(mlxsw_sp, mtu);
+	return 2 * delay_cells + mlxsw_sp_bytes_cells(mlxsw_sp, hdroom->mtu);
 }
 
 int __mlxsw_sp_port_headroom_set(struct mlxsw_sp_port *mlxsw_sp_port,
 				 struct mlxsw_sp_hdroom *hdroom,
-				 int mtu, u8 *prio_tc, bool pause_en, struct ieee_pfc *my_pfc)
+				 u8 *prio_tc, bool pause_en, struct ieee_pfc *my_pfc)
 {
 	struct mlxsw_sp *mlxsw_sp = mlxsw_sp_port->mlxsw_sp;
 	u8 pfc_en = !!my_pfc ? my_pfc->pfc_en : 0;
@@ -682,9 +682,9 @@ int __mlxsw_sp_port_headroom_set(struct mlxsw_sp_port *mlxsw_sp_port,
 			continue;
 
 		lossy = !(pfc || pause_en);
-		thres_cells = mlxsw_sp_pg_buf_threshold_get(mlxsw_sp, mtu);
+		thres_cells = mlxsw_sp_pg_buf_threshold_get(mlxsw_sp, hdroom->mtu);
 		thres_cells = mlxsw_sp_port_headroom_8x_adjust(mlxsw_sp_port, thres_cells);
-		delay_cells = mlxsw_sp_hdroom_buf_delay_get(mlxsw_sp, hdroom, mtu);
+		delay_cells = mlxsw_sp_hdroom_buf_delay_get(mlxsw_sp, hdroom);
 		delay_cells = mlxsw_sp_port_headroom_8x_adjust(mlxsw_sp_port, delay_cells);
 		total_cells = thres_cells + delay_cells;
 
@@ -706,7 +706,7 @@ int __mlxsw_sp_port_headroom_set(struct mlxsw_sp_port *mlxsw_sp_port,
 
 int mlxsw_sp_port_headroom_set(struct mlxsw_sp_port *mlxsw_sp_port,
 			       struct mlxsw_sp_hdroom *hdroom,
-			       int mtu, bool pause_en)
+			       bool pause_en)
 {
 	u8 def_prio_tc[IEEE_8021QAZ_MAX_TCS] = {0};
 	bool dcb_en = !!mlxsw_sp_port->dcb.ets;
@@ -716,19 +716,25 @@ int mlxsw_sp_port_headroom_set(struct mlxsw_sp_port *mlxsw_sp_port,
 	prio_tc = dcb_en ? mlxsw_sp_port->dcb.ets->prio_tc : def_prio_tc;
 	my_pfc = dcb_en ? mlxsw_sp_port->dcb.pfc : NULL;
 
-	return __mlxsw_sp_port_headroom_set(mlxsw_sp_port, hdroom, mtu, prio_tc,
-					    pause_en, my_pfc);
+	return __mlxsw_sp_port_headroom_set(mlxsw_sp_port, hdroom, prio_tc, pause_en, my_pfc);
 }
 
 static int mlxsw_sp_port_change_mtu(struct net_device *dev, int mtu)
 {
 	struct mlxsw_sp_port *mlxsw_sp_port = netdev_priv(dev);
 	bool pause_en = mlxsw_sp_port_is_pause_en(mlxsw_sp_port);
+	struct mlxsw_sp_hdroom orig_hdroom;
+	struct mlxsw_sp_hdroom hdroom;
 	int err;
 
-	err = mlxsw_sp_port_headroom_set(mlxsw_sp_port, mlxsw_sp_port->hdroom, mtu, pause_en);
+	orig_hdroom = *mlxsw_sp_port->hdroom;
+
+	hdroom = orig_hdroom;
+	hdroom.mtu = mtu;
+	err = mlxsw_sp_port_headroom_set(mlxsw_sp_port, &hdroom, pause_en);
 	if (err)
 		return err;
+
 	err = mlxsw_sp_port_mtu_set(mlxsw_sp_port, mtu);
 	if (err)
 		goto err_port_mtu_set;
@@ -736,7 +742,7 @@ static int mlxsw_sp_port_change_mtu(struct net_device *dev, int mtu)
 	return 0;
 
 err_port_mtu_set:
-	mlxsw_sp_port_headroom_set(mlxsw_sp_port, mlxsw_sp_port->hdroom, dev->mtu, pause_en);
+	mlxsw_sp_port_headroom_set(mlxsw_sp_port, &orig_hdroom, pause_en);
 	return err;
 }
 

drivers/net/ethernet/mellanox/mlxsw/spectrum.h

@@ -432,7 +432,7 @@ enum mlxsw_sp_flood_type {
 
 int mlxsw_sp_port_headroom_set(struct mlxsw_sp_port *mlxsw_sp_port,
 			       struct mlxsw_sp_hdroom *hdroom,
-			       int mtu, bool pause_en);
+			       bool pause_en);
 int mlxsw_sp_port_get_stats_raw(struct net_device *dev, int grp,
 				int prio, char *ppcnt_pl);
 int mlxsw_sp_port_admin_status_set(struct mlxsw_sp_port *mlxsw_sp_port,
@@ -441,6 +441,7 @@ int mlxsw_sp_port_admin_status_set(struct mlxsw_sp_port *mlxsw_sp_port,
 /* spectrum_buffers.c */
 struct mlxsw_sp_hdroom {
 	int delay_bytes;
+	int mtu;
 };
 
 int mlxsw_sp_buffers_init(struct mlxsw_sp *mlxsw_sp);
@@ -526,7 +527,7 @@ int mlxsw_sp_port_prio_tc_set(struct mlxsw_sp_port *mlxsw_sp_port,
 			      u8 switch_prio, u8 tclass);
 int __mlxsw_sp_port_headroom_set(struct mlxsw_sp_port *mlxsw_sp_port,
 				 struct mlxsw_sp_hdroom *hdroom,
-				 int mtu, u8 *prio_tc, bool pause_en, struct ieee_pfc *my_pfc);
+				 u8 *prio_tc, bool pause_en, struct ieee_pfc *my_pfc);
 int mlxsw_sp_port_ets_maxrate_set(struct mlxsw_sp_port *mlxsw_sp_port,
 				  enum mlxsw_reg_qeec_hr hr, u8 index,
 				  u8 next_index, u32 maxrate, u8 burst_size);

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

@@ -998,6 +998,7 @@ int mlxsw_sp_port_buffers_init(struct mlxsw_sp_port *mlxsw_sp_port)
 	mlxsw_sp_port->hdroom = kzalloc(sizeof(*mlxsw_sp_port->hdroom), GFP_KERNEL);
 	if (!mlxsw_sp_port->hdroom)
 		return -ENOMEM;
+	mlxsw_sp_port->hdroom->mtu = mlxsw_sp_port->dev->mtu;
 
 	err = mlxsw_sp_port_headroom_init(mlxsw_sp_port);
 	if (err)

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

@@ -121,7 +121,7 @@ static int mlxsw_sp_port_headroom_ets_set(struct mlxsw_sp_port *mlxsw_sp_port,
 	/* Create the required PGs, but don't destroy existing ones, as
 	 * traffic is still directed to them.
 	 */
-	err = __mlxsw_sp_port_headroom_set(mlxsw_sp_port, mlxsw_sp_port->hdroom, dev->mtu,
+	err = __mlxsw_sp_port_headroom_set(mlxsw_sp_port, mlxsw_sp_port->hdroom,
 					   ets->prio_tc, pause_en,
 					   mlxsw_sp_port->dcb.pfc);
 	if (err) {
@@ -622,8 +622,7 @@ static int mlxsw_sp_dcbnl_ieee_setpfc(struct net_device *dev,
 	else
 		hdroom.delay_bytes = 0;
 
-	err = __mlxsw_sp_port_headroom_set(mlxsw_sp_port, &hdroom, dev->mtu,
-					   mlxsw_sp_port->dcb.ets->prio_tc,
+	err = __mlxsw_sp_port_headroom_set(mlxsw_sp_port, &hdroom, mlxsw_sp_port->dcb.ets->prio_tc,
 					   pause_en, pfc);
 	if (err) {
 		netdev_err(dev, "Failed to configure port's headroom for PFC\n");
@@ -642,9 +641,8 @@ static int mlxsw_sp_dcbnl_ieee_setpfc(struct net_device *dev,
 	return 0;
 
 err_port_pfc_set:
-	__mlxsw_sp_port_headroom_set(mlxsw_sp_port, &orig_hdroom, dev->mtu,
-				     mlxsw_sp_port->dcb.ets->prio_tc, pause_en,
-				     mlxsw_sp_port->dcb.pfc);
+	__mlxsw_sp_port_headroom_set(mlxsw_sp_port, &orig_hdroom, mlxsw_sp_port->dcb.ets->prio_tc,
+				     pause_en, mlxsw_sp_port->dcb.pfc);
 	return err;
 }
 

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

@@ -224,7 +224,7 @@ static int mlxsw_sp_port_set_pauseparam(struct net_device *dev,
 	else
 		hdroom.delay_bytes = 0;
 
-	err = mlxsw_sp_port_headroom_set(mlxsw_sp_port, &hdroom, dev->mtu, pause_en);
+	err = mlxsw_sp_port_headroom_set(mlxsw_sp_port, &hdroom, pause_en);
 	if (err) {
 		netdev_err(dev, "Failed to configure port's headroom\n");
 		return err;
@@ -243,7 +243,7 @@ static int mlxsw_sp_port_set_pauseparam(struct net_device *dev,
 
 err_port_pause_configure:
 	pause_en = mlxsw_sp_port_is_pause_en(mlxsw_sp_port);
-	mlxsw_sp_port_headroom_set(mlxsw_sp_port, &orig_hdroom, dev->mtu, pause_en);
+	mlxsw_sp_port_headroom_set(mlxsw_sp_port, &orig_hdroom, pause_en);
 	return err;
 }