net: dpaa: use __dev_mc_sync in dpaa_set_rx_mode()

The original driver first unregisters then re-registers all multicast
addresses in the struct net_device_ops::ndo_set_rx_mode() callback.

As the networking stack calls ndo_set_rx_mode() if a single multicast
address change occurs, a significant amount of time may be used to first
unregister and then re-register unchanged multicast addresses. This
leads to performance issues when tracking large numbers of multicast
addresses.

Replace the unregister and register loop and the hand crafted
mc_addr_list list handling with __dev_mc_sync(), to only update entries
which have changed.

On profiling with an fsl_dpa NIC, this patch presented a speedup of
around 40 when successively setting up 2000 multicast groups using
setsockopt(), without drawbacks on smaller numbers of multicast groups.

Signed-off-by: Jonas Rebmann <jre@pengutronix.de>
Reviewed-by: Sean Anderson <sean.anderson@seco.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Author: jonrebm

drivers/net/ethernet/freescale/dpaa/dpaa_eth.c

@@ -463,6 +463,22 @@ static int dpaa_set_mac_address(struct net_device *net_dev, void *addr)
 	return 0;
 }
 
+static int dpaa_addr_sync(struct net_device *net_dev, const u8 *addr)
+{
+	const struct dpaa_priv *priv = netdev_priv(net_dev);
+
+	return priv->mac_dev->add_hash_mac_addr(priv->mac_dev->fman_mac,
+						(enet_addr_t *)addr);
+}
+
+static int dpaa_addr_unsync(struct net_device *net_dev, const u8 *addr)
+{
+	const struct dpaa_priv *priv = netdev_priv(net_dev);
+
+	return priv->mac_dev->remove_hash_mac_addr(priv->mac_dev->fman_mac,
+						   (enet_addr_t *)addr);
+}
+
 static void dpaa_set_rx_mode(struct net_device *net_dev)
 {
 	const struct dpaa_priv	*priv;
@@ -490,9 +506,9 @@ static void dpaa_set_rx_mode(struct net_device *net_dev)
 				  err);
 	}
 
-	err = priv->mac_dev->set_multi(net_dev, priv->mac_dev);
+	err = __dev_mc_sync(net_dev, dpaa_addr_sync, dpaa_addr_unsync);
 	if (err < 0)
-		netif_err(priv, drv, net_dev, "mac_dev->set_multi() = %d\n",
+		netif_err(priv, drv, net_dev, "dpaa_addr_sync() = %d\n",
 			  err);
 }
 

drivers/net/ethernet/freescale/fman/fman_dtsec.c

@@ -1415,7 +1415,6 @@ int dtsec_initialization(struct mac_device *mac_dev,
 	mac_dev->set_exception		= dtsec_set_exception;
 	mac_dev->set_allmulti		= dtsec_set_allmulti;
 	mac_dev->set_tstamp		= dtsec_set_tstamp;
-	mac_dev->set_multi		= fman_set_multi;
 	mac_dev->enable			= dtsec_enable;
 	mac_dev->disable		= dtsec_disable;
 

drivers/net/ethernet/freescale/fman/fman_memac.c

@@ -1087,7 +1087,6 @@ int memac_initialization(struct mac_device *mac_dev,
 	mac_dev->set_exception		= memac_set_exception;
 	mac_dev->set_allmulti		= memac_set_allmulti;
 	mac_dev->set_tstamp		= memac_set_tstamp;
-	mac_dev->set_multi		= fman_set_multi;
 	mac_dev->enable			= memac_enable;
 	mac_dev->disable		= memac_disable;
 

drivers/net/ethernet/freescale/fman/fman_tgec.c

@@ -771,7 +771,6 @@ int tgec_initialization(struct mac_device *mac_dev,
 	mac_dev->set_exception		= tgec_set_exception;
 	mac_dev->set_allmulti		= tgec_set_allmulti;
 	mac_dev->set_tstamp		= tgec_set_tstamp;
-	mac_dev->set_multi		= fman_set_multi;
 	mac_dev->enable			= tgec_enable;
 	mac_dev->disable		= tgec_disable;
 

drivers/net/ethernet/freescale/fman/mac.c

@@ -32,8 +32,6 @@ MODULE_DESCRIPTION("FSL FMan MAC API based driver");
 struct mac_priv_s {
 	u8				cell_index;
 	struct fman			*fman;
-	/* List of multicast addresses */
-	struct list_head		mc_addr_list;
 	struct platform_device		*eth_dev;
 	u16				speed;
 };
@@ -57,44 +55,6 @@ static void mac_exception(struct mac_device *mac_dev,
 		__func__, ex);
 }
 
-int fman_set_multi(struct net_device *net_dev, struct mac_device *mac_dev)
-{
-	struct mac_priv_s	*priv;
-	struct mac_address	*old_addr, *tmp;
-	struct netdev_hw_addr	*ha;
-	int			err;
-	enet_addr_t		*addr;
-
-	priv = mac_dev->priv;
-
-	/* Clear previous address list */
-	list_for_each_entry_safe(old_addr, tmp, &priv->mc_addr_list, list) {
-		addr = (enet_addr_t *)old_addr->addr;
-		err = mac_dev->remove_hash_mac_addr(mac_dev->fman_mac, addr);
-		if (err < 0)
-			return err;
-
-		list_del(&old_addr->list);
-		kfree(old_addr);
-	}
-
-	/* Add all the addresses from the new list */
-	netdev_for_each_mc_addr(ha, net_dev) {
-		addr = (enet_addr_t *)ha->addr;
-		err = mac_dev->add_hash_mac_addr(mac_dev->fman_mac, addr);
-		if (err < 0)
-			return err;
-
-		tmp = kmalloc(sizeof(*tmp), GFP_ATOMIC);
-		if (!tmp)
-			return -ENOMEM;
-
-		ether_addr_copy(tmp->addr, ha->addr);
-		list_add(&tmp->list, &priv->mc_addr_list);
-	}
-	return 0;
-}
-
 static DEFINE_MUTEX(eth_lock);
 
 static struct platform_device *dpaa_eth_add_device(int fman_id,
@@ -181,8 +141,6 @@ static int mac_probe(struct platform_device *_of_dev)
 	mac_dev->priv = priv;
 	mac_dev->dev = dev;
 
-	INIT_LIST_HEAD(&priv->mc_addr_list);
-
 	/* Get the FM node */
 	dev_node = of_get_parent(mac_node);
 	if (!dev_node) {

drivers/net/ethernet/freescale/fman/mac.h

@@ -39,8 +39,6 @@ struct mac_device {
 	int (*change_addr)(struct fman_mac *mac_dev, const enet_addr_t *enet_addr);
 	int (*set_allmulti)(struct fman_mac *mac_dev, bool enable);
 	int (*set_tstamp)(struct fman_mac *mac_dev, bool enable);
-	int (*set_multi)(struct net_device *net_dev,
-			 struct mac_device *mac_dev);
 	int (*set_exception)(struct fman_mac *mac_dev,
 			     enum fman_mac_exceptions exception, bool enable);
 	int (*add_hash_mac_addr)(struct fman_mac *mac_dev,