From: Ido Schimmel <idosch@xxxxxxxxxxxx>
Date: Wed, 5 Dec 2018 15:50:23 +0000
> +static struct switchdev_notifier_vxlan_fdb_info
> +vxlan_fdb_switchdev_notifier_info(const struct vxlan_dev *vxlan,
> + const struct vxlan_fdb *fdb,
> + const struct vxlan_rdst *rd)
> +{
> + struct switchdev_notifier_vxlan_fdb_info fdb_info = {
> + .info.dev = vxlan->dev,
> + .remote_ip = rd->remote_ip,
> + .remote_port = rd->remote_port,
> + .remote_vni = rd->remote_vni,
> + .remote_ifindex = rd->remote_ifindex,
> + .vni = fdb->vni,
> + .offloaded = rd->offloaded,
> + .added_by_user = fdb->flags & NTF_VXLAN_ADDED_BY_USER,
> + };
> +
> + memcpy(fdb_info.eth_addr, fdb->eth_addr, ETH_ALEN);
> + return fdb_info;
> +}
Never return a structure by value from a function. Do you have any idea
how the compiler implement this?
In the one call site in vxlan.c after this patch is applied, _two_
switchdev_notifier_cxlan_fdb_info objects are allocated on the stack.
vxlan_fdb_swtich_dev_notifier_info() fills in the first one, and
then the caller copies that into the second one.
A huge waste.
Please just pass "&info" as an argument.
