diff mbox series

[v3,net-next,08/12] net: mscc: ocelot: drop the use of the "lags" array

Message ID 20210205130240.4072854-9-vladimir.oltean@nxp.com (mailing list archive)
State Superseded
Delegated to: Netdev Maintainers
Headers show
Series LAG offload for Ocelot DSA switches | expand

Checks

Context Check Description
netdev/cover_letter success Link
netdev/fixes_present success Link
netdev/patch_count success Link
netdev/tree_selection success Clearly marked for net-next
netdev/subject_prefix success Link
netdev/cc_maintainers success CCed 7 of 7 maintainers
netdev/source_inline success Was 0 now: 0
netdev/verify_signedoff success Link
netdev/module_param success Was 0 now: 0
netdev/build_32bit success Errors and warnings before: 0 this patch: 0
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/verify_fixes success Link
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 161 lines checked
netdev/build_allmodconfig_warn success Errors and warnings before: 0 this patch: 0
netdev/header_inline success Link
netdev/stable success Stable not CCed

Commit Message

Vladimir Oltean Feb. 5, 2021, 1:02 p.m. UTC
We can now simplify the implementation by always using ocelot_get_bond_mask
to look up the other ports that are offloading the same bonding interface
as us.

In ocelot_set_aggr_pgids, the code had a way to uniquely iterate through
LAGs. We need to achieve the same behavior by marking each LAG as visited,
which we do now by using a temporary 32-bit "visited" bitmask. This is
ok and we do not need dynamic memory allocation, because we know that
this switch architecture will not have more than 32 ports (the PGID port
masks are 32-bit anyway).

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
---
Changes in v3:
Using a "visited" bit mask to avoid memory allocation.

Changes in v2:
Context looks a bit different.

 drivers/net/ethernet/mscc/ocelot.c | 95 ++++++++++++------------------
 include/soc/mscc/ocelot.h          |  2 -
 2 files changed, 39 insertions(+), 58 deletions(-)
diff mbox series

Patch

diff --git a/drivers/net/ethernet/mscc/ocelot.c b/drivers/net/ethernet/mscc/ocelot.c
index 5d765245c6d3..c906c449d2dd 100644
--- a/drivers/net/ethernet/mscc/ocelot.c
+++ b/drivers/net/ethernet/mscc/ocelot.c
@@ -957,21 +957,11 @@  void ocelot_apply_bridge_fwd_mask(struct ocelot *ocelot)
 			mask = GENMASK(ocelot->num_phys_ports - 1, 0);
 			mask &= ~cpu_fwd_mask;
 		} else if (ocelot->bridge_fwd_mask & BIT(port)) {
-			int lag;
+			struct net_device *bond = ocelot_port->bond;
 
 			mask = ocelot->bridge_fwd_mask & ~BIT(port);
-
-			for (lag = 0; lag < ocelot->num_phys_ports; lag++) {
-				unsigned long bond_mask = ocelot->lags[lag];
-
-				if (!bond_mask)
-					continue;
-
-				if (bond_mask & BIT(port)) {
-					mask &= ~bond_mask;
-					break;
-				}
-			}
+			if (bond)
+				mask &= ~ocelot_get_bond_mask(ocelot, bond);
 		} else {
 			/* Standalone ports forward only to DSA tag_8021q CPU
 			 * ports (if those exist), or to the hardware CPU port
@@ -1277,6 +1267,7 @@  EXPORT_SYMBOL(ocelot_port_bridge_leave);
 
 static void ocelot_set_aggr_pgids(struct ocelot *ocelot)
 {
+	unsigned long visited = GENMASK(ocelot->num_phys_ports - 1, 0);
 	int i, port, lag;
 
 	/* Reset destination and aggregation PGIDS */
@@ -1287,16 +1278,35 @@  static void ocelot_set_aggr_pgids(struct ocelot *ocelot)
 		ocelot_write_rix(ocelot, GENMASK(ocelot->num_phys_ports - 1, 0),
 				 ANA_PGID_PGID, i);
 
-	/* Now, set PGIDs for each LAG */
+	/* The visited ports bitmask holds the list of ports offloading any
+	 * bonding interface. Initially we mark all these ports as unvisited,
+	 * then every time we visit a port in this bitmask, we know that it is
+	 * the lowest numbered port, i.e. the one whose logical ID == physical
+	 * port ID == LAG ID. So we mark as visited all further ports in the
+	 * bitmask that are offloading the same bonding interface. This way,
+	 * we set up the aggregation PGIDs only once per bonding interface.
+	 */
+	for (port = 0; port < ocelot->num_phys_ports; port++) {
+		struct ocelot_port *ocelot_port = ocelot->ports[port];
+
+		if (!ocelot_port || !ocelot_port->bond)
+			continue;
+
+		visited &= ~BIT(port);
+	}
+
+	/* Now, set PGIDs for each active LAG */
 	for (lag = 0; lag < ocelot->num_phys_ports; lag++) {
+		struct net_device *bond = ocelot->ports[lag]->bond;
 		unsigned long bond_mask;
 		int aggr_count = 0;
 		u8 aggr_idx[16];
 
-		bond_mask = ocelot->lags[lag];
-		if (!bond_mask)
+		if (!bond || (visited & BIT(lag)))
 			continue;
 
+		bond_mask = ocelot_get_bond_mask(ocelot, bond);
+
 		for_each_set_bit(port, &bond_mask, ocelot->num_phys_ports) {
 			// Destination mask
 			ocelot_write_rix(ocelot, bond_mask,
@@ -1313,6 +1323,19 @@  static void ocelot_set_aggr_pgids(struct ocelot *ocelot)
 			ac |= BIT(aggr_idx[i % aggr_count]);
 			ocelot_write_rix(ocelot, ac, ANA_PGID_PGID, i);
 		}
+
+		/* Mark all ports in the same LAG as visited to avoid applying
+		 * the same config again.
+		 */
+		for (port = lag; port < ocelot->num_phys_ports; port++) {
+			struct ocelot_port *ocelot_port = ocelot->ports[port];
+
+			if (!ocelot_port)
+				continue;
+
+			if (ocelot_port->bond == bond)
+				visited |= BIT(port);
+		}
 	}
 }
 
@@ -1353,30 +1376,11 @@  int ocelot_port_lag_join(struct ocelot *ocelot, int port,
 			 struct net_device *bond,
 			 struct netdev_lag_upper_info *info)
 {
-	u32 bond_mask = 0;
-	int lag;
-
 	if (info->tx_type != NETDEV_LAG_TX_TYPE_HASH)
 		return -EOPNOTSUPP;
 
 	ocelot->ports[port]->bond = bond;
 
-	bond_mask = ocelot_get_bond_mask(ocelot, bond);
-
-	lag = __ffs(bond_mask);
-
-	/* If the new port is the lowest one, use it as the logical port from
-	 * now on
-	 */
-	if (port == lag) {
-		ocelot->lags[port] = bond_mask;
-		bond_mask &= ~BIT(port);
-		if (bond_mask)
-			ocelot->lags[__ffs(bond_mask)] = 0;
-	} else {
-		ocelot->lags[lag] |= BIT(port);
-	}
-
 	ocelot_setup_logical_port_ids(ocelot);
 	ocelot_apply_bridge_fwd_mask(ocelot);
 	ocelot_set_aggr_pgids(ocelot);
@@ -1388,24 +1392,8 @@  EXPORT_SYMBOL(ocelot_port_lag_join);
 void ocelot_port_lag_leave(struct ocelot *ocelot, int port,
 			   struct net_device *bond)
 {
-	int i;
-
 	ocelot->ports[port]->bond = NULL;
 
-	/* Remove port from any lag */
-	for (i = 0; i < ocelot->num_phys_ports; i++)
-		ocelot->lags[i] &= ~BIT(port);
-
-	/* if it was the logical port of the lag, move the lag config to the
-	 * next port
-	 */
-	if (ocelot->lags[port]) {
-		int n = __ffs(ocelot->lags[port]);
-
-		ocelot->lags[n] = ocelot->lags[port];
-		ocelot->lags[port] = 0;
-	}
-
 	ocelot_setup_logical_port_ids(ocelot);
 	ocelot_apply_bridge_fwd_mask(ocelot);
 	ocelot_set_aggr_pgids(ocelot);
@@ -1587,11 +1575,6 @@  int ocelot_init(struct ocelot *ocelot)
 		}
 	}
 
-	ocelot->lags = devm_kcalloc(ocelot->dev, ocelot->num_phys_ports,
-				    sizeof(u32), GFP_KERNEL);
-	if (!ocelot->lags)
-		return -ENOMEM;
-
 	ocelot->stats = devm_kcalloc(ocelot->dev,
 				     ocelot->num_phys_ports * ocelot->num_stats,
 				     sizeof(u64), GFP_KERNEL);
diff --git a/include/soc/mscc/ocelot.h b/include/soc/mscc/ocelot.h
index e36a1ed29c01..089e552719e0 100644
--- a/include/soc/mscc/ocelot.h
+++ b/include/soc/mscc/ocelot.h
@@ -657,8 +657,6 @@  struct ocelot {
 	enum ocelot_tag_prefix		npi_inj_prefix;
 	enum ocelot_tag_prefix		npi_xtr_prefix;
 
-	u32				*lags;
-
 	struct list_head		multicast;
 	struct list_head		pgids;