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Files
ovs/lib/netdev-vport.c
Joe Stringer da4a619179 netdev: Globally track port status changes
Previously, we tracked status changes for ofports on a per-device basis.
Each time in the main thread's loop, we would inspect every ofport
to determine whether the status had changed for corresponding devices.

This patch replaces the per-netdev change_seq with a global 'struct seq'
which tracks status change for all ports. In the average case where
ports are not constantly going up or down, this allows us to check the
sequence once per main loop and not poll any ports. In the worst case,
execution is expected to be similar to how it is currently.

In a test environment of 5000 internal ports and 50 tunnel ports with
bfd, this reduces average CPU usage of the main thread from about 40% to
about 35%.

Signed-off-by: Joe Stringer <joestringer@nicira.com>
Signed-off-by: Ethan Jackson <ethan@nicira.com>
Acked-by: Ethan Jackson <ethan@nicira.com>
2013-12-12 15:03:19 -08:00

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/*
* Copyright (c) 2010, 2011, 2012, 2013 Nicira, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at:
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <config.h>
#include "netdev-vport.h"
#include <errno.h>
#include <fcntl.h>
#include <sys/socket.h>
#include <net/if.h>
#include <sys/ioctl.h>
#include "byte-order.h"
#include "connectivity.h"
#include "daemon.h"
#include "dirs.h"
#include "dpif.h"
#include "hash.h"
#include "hmap.h"
#include "list.h"
#include "netdev-provider.h"
#include "ofpbuf.h"
#include "packets.h"
#include "route-table.h"
#include "seq.h"
#include "shash.h"
#include "socket-util.h"
#include "vlog.h"
VLOG_DEFINE_THIS_MODULE(netdev_vport);
#define VXLAN_DST_PORT 4789
#define LISP_DST_PORT 4341
#define DEFAULT_TTL 64
struct netdev_vport {
struct netdev up;
/* Protects all members below. */
struct ovs_mutex mutex;
uint8_t etheraddr[ETH_ADDR_LEN];
struct netdev_stats stats;
/* Tunnels. */
struct netdev_tunnel_config tnl_cfg;
/* Patch Ports. */
char *peer;
};
struct vport_class {
const char *dpif_port;
struct netdev_class netdev_class;
};
static int netdev_vport_construct(struct netdev *);
static int get_patch_config(const struct netdev *netdev, struct smap *args);
static int get_tunnel_config(const struct netdev *, struct smap *args);
static bool
is_vport_class(const struct netdev_class *class)
{
return class->construct == netdev_vport_construct;
}
static const struct vport_class *
vport_class_cast(const struct netdev_class *class)
{
ovs_assert(is_vport_class(class));
return CONTAINER_OF(class, struct vport_class, netdev_class);
}
static struct netdev_vport *
netdev_vport_cast(const struct netdev *netdev)
{
ovs_assert(is_vport_class(netdev_get_class(netdev)));
return CONTAINER_OF(netdev, struct netdev_vport, up);
}
static const struct netdev_tunnel_config *
get_netdev_tunnel_config(const struct netdev *netdev)
{
return &netdev_vport_cast(netdev)->tnl_cfg;
}
bool
netdev_vport_is_patch(const struct netdev *netdev)
{
const struct netdev_class *class = netdev_get_class(netdev);
return class->get_config == get_patch_config;
}
bool
netdev_vport_is_layer3(const struct netdev *dev)
{
const char *type = netdev_get_type(dev);
return (!strcmp("lisp", type));
}
static bool
netdev_vport_needs_dst_port(const struct netdev *dev)
{
const struct netdev_class *class = netdev_get_class(dev);
const char *type = netdev_get_type(dev);
return (class->get_config == get_tunnel_config &&
(!strcmp("vxlan", type) || !strcmp("lisp", type)));
}
const char *
netdev_vport_class_get_dpif_port(const struct netdev_class *class)
{
return is_vport_class(class) ? vport_class_cast(class)->dpif_port : NULL;
}
const char *
netdev_vport_get_dpif_port(const struct netdev *netdev,
char namebuf[], size_t bufsize)
{
if (netdev_vport_needs_dst_port(netdev)) {
const struct netdev_vport *vport = netdev_vport_cast(netdev);
const char *type = netdev_get_type(netdev);
/*
* Note: IFNAMSIZ is 16 bytes long. The maximum length of a VXLAN
* or LISP port name below is 15 or 14 bytes respectively. Still,
* assert here on the size of strlen(type) in case that changes
* in the future.
*/
BUILD_ASSERT(NETDEV_VPORT_NAME_BUFSIZE >= IFNAMSIZ);
ovs_assert(strlen(type) + 10 < IFNAMSIZ);
snprintf(namebuf, bufsize, "%s_sys_%d", type,
ntohs(vport->tnl_cfg.dst_port));
return namebuf;
} else {
const struct netdev_class *class = netdev_get_class(netdev);
const char *dpif_port = netdev_vport_class_get_dpif_port(class);
return dpif_port ? dpif_port : netdev_get_name(netdev);
}
}
char *
netdev_vport_get_dpif_port_strdup(const struct netdev *netdev)
{
char namebuf[NETDEV_VPORT_NAME_BUFSIZE];
return xstrdup(netdev_vport_get_dpif_port(netdev, namebuf,
sizeof namebuf));
}
static struct netdev *
netdev_vport_alloc(void)
{
struct netdev_vport *netdev = xzalloc(sizeof *netdev);
return &netdev->up;
}
static int
netdev_vport_construct(struct netdev *netdev_)
{
struct netdev_vport *netdev = netdev_vport_cast(netdev_);
ovs_mutex_init(&netdev->mutex);
eth_addr_random(netdev->etheraddr);
route_table_register();
return 0;
}
static void
netdev_vport_destruct(struct netdev *netdev_)
{
struct netdev_vport *netdev = netdev_vport_cast(netdev_);
route_table_unregister();
free(netdev->peer);
ovs_mutex_destroy(&netdev->mutex);
}
static void
netdev_vport_dealloc(struct netdev *netdev_)
{
struct netdev_vport *netdev = netdev_vport_cast(netdev_);
free(netdev);
}
static int
netdev_vport_set_etheraddr(struct netdev *netdev_,
const uint8_t mac[ETH_ADDR_LEN])
{
struct netdev_vport *netdev = netdev_vport_cast(netdev_);
ovs_mutex_lock(&netdev->mutex);
memcpy(netdev->etheraddr, mac, ETH_ADDR_LEN);
ovs_mutex_unlock(&netdev->mutex);
seq_change(connectivity_seq_get());
return 0;
}
static int
netdev_vport_get_etheraddr(const struct netdev *netdev_,
uint8_t mac[ETH_ADDR_LEN])
{
struct netdev_vport *netdev = netdev_vport_cast(netdev_);
ovs_mutex_lock(&netdev->mutex);
memcpy(mac, netdev->etheraddr, ETH_ADDR_LEN);
ovs_mutex_unlock(&netdev->mutex);
return 0;
}
static int
tunnel_get_status(const struct netdev *netdev_, struct smap *smap)
{
struct netdev_vport *netdev = netdev_vport_cast(netdev_);
char iface[IFNAMSIZ];
ovs_be32 route;
ovs_mutex_lock(&netdev->mutex);
route = netdev->tnl_cfg.ip_dst;
ovs_mutex_unlock(&netdev->mutex);
if (route_table_get_name(route, iface)) {
struct netdev *egress_netdev;
smap_add(smap, "tunnel_egress_iface", iface);
if (!netdev_open(iface, "system", &egress_netdev)) {
smap_add(smap, "tunnel_egress_iface_carrier",
netdev_get_carrier(egress_netdev) ? "up" : "down");
netdev_close(egress_netdev);
}
}
return 0;
}
static int
netdev_vport_update_flags(struct netdev *netdev OVS_UNUSED,
enum netdev_flags off,
enum netdev_flags on OVS_UNUSED,
enum netdev_flags *old_flagsp)
{
if (off & (NETDEV_UP | NETDEV_PROMISC)) {
return EOPNOTSUPP;
}
*old_flagsp = NETDEV_UP | NETDEV_PROMISC;
return 0;
}
static void
netdev_vport_run(void)
{
route_table_run();
}
static void
netdev_vport_wait(void)
{
route_table_wait();
}
/* Code specific to tunnel types. */
static ovs_be64
parse_key(const struct smap *args, const char *name,
bool *present, bool *flow)
{
const char *s;
*present = false;
*flow = false;
s = smap_get(args, name);
if (!s) {
s = smap_get(args, "key");
if (!s) {
return 0;
}
}
*present = true;
if (!strcmp(s, "flow")) {
*flow = true;
return 0;
} else {
return htonll(strtoull(s, NULL, 0));
}
}
static int
set_tunnel_config(struct netdev *dev_, const struct smap *args)
{
struct netdev_vport *dev = netdev_vport_cast(dev_);
const char *name = netdev_get_name(dev_);
const char *type = netdev_get_type(dev_);
bool ipsec_mech_set, needs_dst_port, has_csum;
struct netdev_tunnel_config tnl_cfg;
struct smap_node *node;
has_csum = strstr(type, "gre");
ipsec_mech_set = false;
memset(&tnl_cfg, 0, sizeof tnl_cfg);
needs_dst_port = netdev_vport_needs_dst_port(dev_);
tnl_cfg.ipsec = strstr(type, "ipsec");
tnl_cfg.dont_fragment = true;
SMAP_FOR_EACH (node, args) {
if (!strcmp(node->key, "remote_ip")) {
struct in_addr in_addr;
if (!strcmp(node->value, "flow")) {
tnl_cfg.ip_dst_flow = true;
tnl_cfg.ip_dst = htonl(0);
} else if (lookup_ip(node->value, &in_addr)) {
VLOG_WARN("%s: bad %s 'remote_ip'", name, type);
} else if (ip_is_multicast(in_addr.s_addr)) {
VLOG_WARN("%s: multicast remote_ip="IP_FMT" not allowed",
name, IP_ARGS(in_addr.s_addr));
return EINVAL;
} else {
tnl_cfg.ip_dst = in_addr.s_addr;
}
} else if (!strcmp(node->key, "local_ip")) {
struct in_addr in_addr;
if (!strcmp(node->value, "flow")) {
tnl_cfg.ip_src_flow = true;
tnl_cfg.ip_src = htonl(0);
} else if (lookup_ip(node->value, &in_addr)) {
VLOG_WARN("%s: bad %s 'local_ip'", name, type);
} else {
tnl_cfg.ip_src = in_addr.s_addr;
}
} else if (!strcmp(node->key, "tos")) {
if (!strcmp(node->value, "inherit")) {
tnl_cfg.tos_inherit = true;
} else {
char *endptr;
int tos;
tos = strtol(node->value, &endptr, 0);
if (*endptr == '\0' && tos == (tos & IP_DSCP_MASK)) {
tnl_cfg.tos = tos;
} else {
VLOG_WARN("%s: invalid TOS %s", name, node->value);
}
}
} else if (!strcmp(node->key, "ttl")) {
if (!strcmp(node->value, "inherit")) {
tnl_cfg.ttl_inherit = true;
} else {
tnl_cfg.ttl = atoi(node->value);
}
} else if (!strcmp(node->key, "dst_port") && needs_dst_port) {
tnl_cfg.dst_port = htons(atoi(node->value));
} else if (!strcmp(node->key, "csum") && has_csum) {
if (!strcmp(node->value, "true")) {
tnl_cfg.csum = true;
}
} else if (!strcmp(node->key, "df_default")) {
if (!strcmp(node->value, "false")) {
tnl_cfg.dont_fragment = false;
}
} else if (!strcmp(node->key, "peer_cert") && tnl_cfg.ipsec) {
if (smap_get(args, "certificate")) {
ipsec_mech_set = true;
} else {
const char *use_ssl_cert;
/* If the "use_ssl_cert" is true, then "certificate" and
* "private_key" will be pulled from the SSL table. The
* use of this option is strongly discouraged, since it
* will like be removed when multiple SSL configurations
* are supported by OVS.
*/
use_ssl_cert = smap_get(args, "use_ssl_cert");
if (!use_ssl_cert || strcmp(use_ssl_cert, "true")) {
VLOG_ERR("%s: 'peer_cert' requires 'certificate' argument",
name);
return EINVAL;
}
ipsec_mech_set = true;
}
} else if (!strcmp(node->key, "psk") && tnl_cfg.ipsec) {
ipsec_mech_set = true;
} else if (tnl_cfg.ipsec
&& (!strcmp(node->key, "certificate")
|| !strcmp(node->key, "private_key")
|| !strcmp(node->key, "use_ssl_cert"))) {
/* Ignore options not used by the netdev. */
} else if (!strcmp(node->key, "key") ||
!strcmp(node->key, "in_key") ||
!strcmp(node->key, "out_key")) {
/* Handled separately below. */
} else {
VLOG_WARN("%s: unknown %s argument '%s'", name, type, node->key);
}
}
/* Add a default destination port for VXLAN if none specified. */
if (!strcmp(type, "vxlan") && !tnl_cfg.dst_port) {
tnl_cfg.dst_port = htons(VXLAN_DST_PORT);
}
/* Add a default destination port for LISP if none specified. */
if (!strcmp(type, "lisp") && !tnl_cfg.dst_port) {
tnl_cfg.dst_port = htons(LISP_DST_PORT);
}
if (tnl_cfg.ipsec) {
static struct ovs_mutex mutex = OVS_MUTEX_INITIALIZER;
static pid_t pid = 0;
ovs_mutex_lock(&mutex);
if (pid <= 0) {
char *file_name = xasprintf("%s/%s", ovs_rundir(),
"ovs-monitor-ipsec.pid");
pid = read_pidfile(file_name);
free(file_name);
}
ovs_mutex_unlock(&mutex);
if (pid < 0) {
VLOG_ERR("%s: IPsec requires the ovs-monitor-ipsec daemon",
name);
return EINVAL;
}
if (smap_get(args, "peer_cert") && smap_get(args, "psk")) {
VLOG_ERR("%s: cannot define both 'peer_cert' and 'psk'", name);
return EINVAL;
}
if (!ipsec_mech_set) {
VLOG_ERR("%s: IPsec requires an 'peer_cert' or psk' argument",
name);
return EINVAL;
}
}
if (!tnl_cfg.ip_dst && !tnl_cfg.ip_dst_flow) {
VLOG_ERR("%s: %s type requires valid 'remote_ip' argument",
name, type);
return EINVAL;
}
if (tnl_cfg.ip_src_flow && !tnl_cfg.ip_dst_flow) {
VLOG_ERR("%s: %s type requires 'remote_ip=flow' with 'local_ip=flow'",
name, type);
return EINVAL;
}
if (!tnl_cfg.ttl) {
tnl_cfg.ttl = DEFAULT_TTL;
}
tnl_cfg.in_key = parse_key(args, "in_key",
&tnl_cfg.in_key_present,
&tnl_cfg.in_key_flow);
tnl_cfg.out_key = parse_key(args, "out_key",
&tnl_cfg.out_key_present,
&tnl_cfg.out_key_flow);
ovs_mutex_lock(&dev->mutex);
dev->tnl_cfg = tnl_cfg;
seq_change(connectivity_seq_get());
ovs_mutex_unlock(&dev->mutex);
return 0;
}
static int
get_tunnel_config(const struct netdev *dev, struct smap *args)
{
struct netdev_vport *netdev = netdev_vport_cast(dev);
struct netdev_tunnel_config tnl_cfg;
ovs_mutex_lock(&netdev->mutex);
tnl_cfg = netdev->tnl_cfg;
ovs_mutex_unlock(&netdev->mutex);
if (tnl_cfg.ip_dst) {
smap_add_format(args, "remote_ip", IP_FMT, IP_ARGS(tnl_cfg.ip_dst));
} else if (tnl_cfg.ip_dst_flow) {
smap_add(args, "remote_ip", "flow");
}
if (tnl_cfg.ip_src) {
smap_add_format(args, "local_ip", IP_FMT, IP_ARGS(tnl_cfg.ip_src));
} else if (tnl_cfg.ip_src_flow) {
smap_add(args, "local_ip", "flow");
}
if (tnl_cfg.in_key_flow && tnl_cfg.out_key_flow) {
smap_add(args, "key", "flow");
} else if (tnl_cfg.in_key_present && tnl_cfg.out_key_present
&& tnl_cfg.in_key == tnl_cfg.out_key) {
smap_add_format(args, "key", "%"PRIu64, ntohll(tnl_cfg.in_key));
} else {
if (tnl_cfg.in_key_flow) {
smap_add(args, "in_key", "flow");
} else if (tnl_cfg.in_key_present) {
smap_add_format(args, "in_key", "%"PRIu64,
ntohll(tnl_cfg.in_key));
}
if (tnl_cfg.out_key_flow) {
smap_add(args, "out_key", "flow");
} else if (tnl_cfg.out_key_present) {
smap_add_format(args, "out_key", "%"PRIu64,
ntohll(tnl_cfg.out_key));
}
}
if (tnl_cfg.ttl_inherit) {
smap_add(args, "ttl", "inherit");
} else if (tnl_cfg.ttl != DEFAULT_TTL) {
smap_add_format(args, "ttl", "%"PRIu8, tnl_cfg.ttl);
}
if (tnl_cfg.tos_inherit) {
smap_add(args, "tos", "inherit");
} else if (tnl_cfg.tos) {
smap_add_format(args, "tos", "0x%x", tnl_cfg.tos);
}
if (tnl_cfg.dst_port) {
uint16_t dst_port = ntohs(tnl_cfg.dst_port);
const char *type = netdev_get_type(dev);
if ((!strcmp("vxlan", type) && dst_port != VXLAN_DST_PORT) ||
(!strcmp("lisp", type) && dst_port != LISP_DST_PORT)) {
smap_add_format(args, "dst_port", "%d", dst_port);
}
}
if (tnl_cfg.csum) {
smap_add(args, "csum", "true");
}
if (!tnl_cfg.dont_fragment) {
smap_add(args, "df_default", "false");
}
return 0;
}
/* Code specific to patch ports. */
/* If 'netdev' is a patch port, returns the name of its peer as a malloc()'d
* string that the caller must free.
*
* If 'netdev' is not a patch port, returns NULL. */
char *
netdev_vport_patch_peer(const struct netdev *netdev_)
{
char *peer = NULL;
if (netdev_vport_is_patch(netdev_)) {
struct netdev_vport *netdev = netdev_vport_cast(netdev_);
ovs_mutex_lock(&netdev->mutex);
if (netdev->peer) {
peer = xstrdup(netdev->peer);
}
ovs_mutex_unlock(&netdev->mutex);
}
return peer;
}
void
netdev_vport_inc_rx(const struct netdev *netdev,
const struct dpif_flow_stats *stats)
{
if (is_vport_class(netdev_get_class(netdev))) {
struct netdev_vport *dev = netdev_vport_cast(netdev);
ovs_mutex_lock(&dev->mutex);
dev->stats.rx_packets += stats->n_packets;
dev->stats.rx_bytes += stats->n_bytes;
ovs_mutex_unlock(&dev->mutex);
}
}
void
netdev_vport_inc_tx(const struct netdev *netdev,
const struct dpif_flow_stats *stats)
{
if (is_vport_class(netdev_get_class(netdev))) {
struct netdev_vport *dev = netdev_vport_cast(netdev);
ovs_mutex_lock(&dev->mutex);
dev->stats.tx_packets += stats->n_packets;
dev->stats.tx_bytes += stats->n_bytes;
ovs_mutex_unlock(&dev->mutex);
}
}
static int
get_patch_config(const struct netdev *dev_, struct smap *args)
{
struct netdev_vport *dev = netdev_vport_cast(dev_);
ovs_mutex_lock(&dev->mutex);
if (dev->peer) {
smap_add(args, "peer", dev->peer);
}
ovs_mutex_unlock(&dev->mutex);
return 0;
}
static int
set_patch_config(struct netdev *dev_, const struct smap *args)
{
struct netdev_vport *dev = netdev_vport_cast(dev_);
const char *name = netdev_get_name(dev_);
const char *peer;
peer = smap_get(args, "peer");
if (!peer) {
VLOG_ERR("%s: patch type requires valid 'peer' argument", name);
return EINVAL;
}
if (smap_count(args) > 1) {
VLOG_ERR("%s: patch type takes only a 'peer' argument", name);
return EINVAL;
}
if (!strcmp(name, peer)) {
VLOG_ERR("%s: patch peer must not be self", name);
return EINVAL;
}
ovs_mutex_lock(&dev->mutex);
free(dev->peer);
dev->peer = xstrdup(peer);
seq_change(connectivity_seq_get());
ovs_mutex_unlock(&dev->mutex);
return 0;
}
static int
get_stats(const struct netdev *netdev, struct netdev_stats *stats)
{
struct netdev_vport *dev = netdev_vport_cast(netdev);
ovs_mutex_lock(&dev->mutex);
*stats = dev->stats;
ovs_mutex_unlock(&dev->mutex);
return 0;
}
#define VPORT_FUNCTIONS(GET_CONFIG, SET_CONFIG, \
GET_TUNNEL_CONFIG, GET_STATUS) \
NULL, \
netdev_vport_run, \
netdev_vport_wait, \
\
netdev_vport_alloc, \
netdev_vport_construct, \
netdev_vport_destruct, \
netdev_vport_dealloc, \
GET_CONFIG, \
SET_CONFIG, \
GET_TUNNEL_CONFIG, \
\
NULL, /* send */ \
NULL, /* send_wait */ \
\
netdev_vport_set_etheraddr, \
netdev_vport_get_etheraddr, \
NULL, /* get_mtu */ \
NULL, /* set_mtu */ \
NULL, /* get_ifindex */ \
NULL, /* get_carrier */ \
NULL, /* get_carrier_resets */ \
NULL, /* get_miimon */ \
get_stats, \
NULL, /* set_stats */ \
\
NULL, /* get_features */ \
NULL, /* set_advertisements */ \
\
NULL, /* set_policing */ \
NULL, /* get_qos_types */ \
NULL, /* get_qos_capabilities */ \
NULL, /* get_qos */ \
NULL, /* set_qos */ \
NULL, /* get_queue */ \
NULL, /* set_queue */ \
NULL, /* delete_queue */ \
NULL, /* get_queue_stats */ \
NULL, /* queue_dump_start */ \
NULL, /* queue_dump_next */ \
NULL, /* queue_dump_done */ \
NULL, /* dump_queue_stats */ \
\
NULL, /* get_in4 */ \
NULL, /* set_in4 */ \
NULL, /* get_in6 */ \
NULL, /* add_router */ \
NULL, /* get_next_hop */ \
GET_STATUS, \
NULL, /* arp_lookup */ \
\
netdev_vport_update_flags, \
\
NULL, /* rx_alloc */ \
NULL, /* rx_construct */ \
NULL, /* rx_destruct */ \
NULL, /* rx_dealloc */ \
NULL, /* rx_recv */ \
NULL, /* rx_wait */ \
NULL, /* rx_drain */
#define TUNNEL_CLASS(NAME, DPIF_PORT) \
{ DPIF_PORT, \
{ NAME, VPORT_FUNCTIONS(get_tunnel_config, \
set_tunnel_config, \
get_netdev_tunnel_config, \
tunnel_get_status) }}
void
netdev_vport_tunnel_register(void)
{
static const struct vport_class vport_classes[] = {
TUNNEL_CLASS("gre", "gre_system"),
TUNNEL_CLASS("ipsec_gre", "gre_system"),
TUNNEL_CLASS("gre64", "gre64_system"),
TUNNEL_CLASS("ipsec_gre64", "gre64_system"),
TUNNEL_CLASS("vxlan", "vxlan_system"),
TUNNEL_CLASS("lisp", "lisp_system")
};
static struct ovsthread_once once = OVSTHREAD_ONCE_INITIALIZER;
if (ovsthread_once_start(&once)) {
int i;
for (i = 0; i < ARRAY_SIZE(vport_classes); i++) {
netdev_register_provider(&vport_classes[i].netdev_class);
}
ovsthread_once_done(&once);
}
}
void
netdev_vport_patch_register(void)
{
static const struct vport_class patch_class =
{ NULL,
{ "patch", VPORT_FUNCTIONS(get_patch_config,
set_patch_config,
NULL,
NULL) }};
netdev_register_provider(&patch_class.netdev_class);
}