diff mbox series

[v3,net-next,06/12] net: mscc: ocelot: avoid unneeded "lp" variable in LAG join

Message ID 20210205130240.4072854-7-vladimir.oltean@nxp.com (mailing list archive)
State Superseded
Delegated to: Netdev Maintainers
Headers show
Series LAG offload for Ocelot DSA switches | expand

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Commit Message

Vladimir Oltean Feb. 5, 2021, 1:02 p.m. UTC
The index of the LAG is equal to the logical port ID that all the
physical port members have, which is further equal to the index of the
first physical port that is a member of the LAG.

The code gets a bit carried away with logic like this:

	if (a == b)
		c = a;
	else
		c = b;

which can be simplified, of course, into:

	c = b;

(with a being port, b being lp, c being lag)

This further makes the "lp" variable redundant, since we can use "lag"
everywhere where "lp" (logical port) was used. So instead of a "c = b"
assignment, we can do a complete deletion of b. Only one comment here:

		if (bond_mask) {
			lp = __ffs(bond_mask);
			ocelot->lags[lp] = 0;
		}

lp was clobbered before, because it was used as a temporary variable to
hold the new smallest port ID from the bond. Now that we don't have "lp"
any longer, we'll just avoid the temporary variable and zeroize the
bonding mask directly.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
---
Changes in v3:
None.

Changes in v2:
None.

 drivers/net/ethernet/mscc/ocelot.c | 16 ++++++----------
 1 file changed, 6 insertions(+), 10 deletions(-)
diff mbox series

Patch

diff --git a/drivers/net/ethernet/mscc/ocelot.c b/drivers/net/ethernet/mscc/ocelot.c
index 127beedcccde..7f6fb872f588 100644
--- a/drivers/net/ethernet/mscc/ocelot.c
+++ b/drivers/net/ethernet/mscc/ocelot.c
@@ -1338,7 +1338,7 @@  int ocelot_port_lag_join(struct ocelot *ocelot, int port,
 			 struct netdev_lag_upper_info *info)
 {
 	u32 bond_mask = 0;
-	int lag, lp;
+	int lag;
 
 	if (info->tx_type != NETDEV_LAG_TX_TYPE_HASH)
 		return -EOPNOTSUPP;
@@ -1347,22 +1347,18 @@  int ocelot_port_lag_join(struct ocelot *ocelot, int port,
 
 	bond_mask = ocelot_get_bond_mask(ocelot, bond);
 
-	lp = __ffs(bond_mask);
+	lag = __ffs(bond_mask);
 
 	/* If the new port is the lowest one, use it as the logical port from
 	 * now on
 	 */
-	if (port == lp) {
-		lag = port;
+	if (port == lag) {
 		ocelot->lags[port] = bond_mask;
 		bond_mask &= ~BIT(port);
-		if (bond_mask) {
-			lp = __ffs(bond_mask);
-			ocelot->lags[lp] = 0;
-		}
+		if (bond_mask)
+			ocelot->lags[__ffs(bond_mask)] = 0;
 	} else {
-		lag = lp;
-		ocelot->lags[lp] |= BIT(port);
+		ocelot->lags[lag] |= BIT(port);
 	}
 
 	ocelot_setup_lag(ocelot, lag);