bridge: vlan: adjust rhashtable initial size and hash locks size

As Stephen pointed out the default initial size is more than we need, so
let's start small (4 elements, thus nelem_hint = 3). Also limit the hash
locks to the number of CPUs as we don't need any write-side scaling and
this looks like the minimum.
Signed-off-by: NNikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/bridge/br_vlan.c

@@ -19,6 +19,8 @@ static const struct rhashtable_params br_vlan_rht_params = {
 	.head_offset = offsetof(struct net_bridge_vlan, vnode),
 	.key_offset = offsetof(struct net_bridge_vlan, vid),
 	.key_len = sizeof(u16),
+	.nelem_hint = 3,
+	.locks_mul = 1,
 	.max_size = VLAN_N_VID,
 	.obj_cmpfn = br_vlan_cmp,
 	.automatic_shrinking = true,