net: amt: Move stats allocation to core

With commit 34d21de ("net: Move {l,t,d}stats allocation to core and
convert veth & vrf"), stats allocation could be done on net core instead
of this driver.

With this new approach, the driver doesn't have to bother with error
handling (allocation failure checking, making sure free happens in the
right spot, etc). This is core responsibility now.

Move amt driver to leverage the core allocation.

Signed-off-by: Breno Leitao <[email protected]>
Reviewed-by: Taehee Yoo <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>

Author: leitao

drivers/net/amt.c

@@ -3063,15 +3063,10 @@ static int amt_dev_init(struct net_device *dev)
 	int err;
 
 	amt->dev = dev;
-	dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
-	if (!dev->tstats)
-		return -ENOMEM;
 
 	err = gro_cells_init(&amt->gro_cells, dev);
-	if (err) {
-		free_percpu(dev->tstats);
+	if (err)
 		return err;
-	}
 
 	return 0;
 }
@@ -3081,7 +3076,6 @@ static void amt_dev_uninit(struct net_device *dev)
 	struct amt_dev *amt = netdev_priv(dev);
 
 	gro_cells_destroy(&amt->gro_cells);
-	free_percpu(dev->tstats);
 }
 
 static const struct net_device_ops amt_netdev_ops = {
@@ -3111,6 +3105,7 @@ static void amt_link_setup(struct net_device *dev)
 	dev->hw_features	|= NETIF_F_SG | NETIF_F_HW_CSUM;
 	dev->hw_features	|= NETIF_F_FRAGLIST | NETIF_F_RXCSUM;
 	dev->hw_features	|= NETIF_F_GSO_SOFTWARE;
+	dev->pcpu_stat_type	= NETDEV_PCPU_STAT_TSTATS;
 	eth_hw_addr_random(dev);
 	eth_zero_addr(dev->broadcast);
 	ether_setup(dev);