net: add adj_list to save only neighbours

Currently, we distinguish neighbours (first-level linked devices) from
non-neighbours by the neighbour bool in the netdev_adjacent. This could be
quite time-consuming in case we would like to traverse *only* through
neighbours - cause we'd have to traverse through all devices and check for
this flag, and in a (quite common) scenario where we have lots of vlans on
top of bridge, which is on top of a bond - the bonding would have to go
through all those vlans to get its upper neighbour linked devices.

This situation is really unpleasant, cause there are already a lot of cases
when a device with slaves needs to go through them in hot path.

To fix this, introduce a new upper/lower device lists structure -
adj_list, which contains only the neighbours. It works always in
pair with the all_adj_list structure (renamed from upper/lower_dev_list),
i.e. both of them contain the same links, only that all_adj_list contains
also non-neighbour device links. It's really a small change visible,
currently, only for __netdev_adjacent_dev_insert/remove(), and doesn't
change the main linked logic at all.

Also, add some comments a fix a name collision in
netdev_for_each_upper_dev_rcu() and rework the naming by the following
rules:

netdev_(all_)(upper|lower)_*

If "all_" is present, then we work with the whole list of upper/lower
devices, otherwise - only with direct neighbours. Uninline functions - to
get better stack traces.

CC: "David S. Miller" <davem@davemloft.net>
CC: Eric Dumazet <edumazet@google.com>
CC: Jiri Pirko <jiri@resnulli.us>
CC: Alexander Duyck <alexander.h.duyck@intel.com>
CC: Cong Wang <amwang@redhat.com>
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Veaceslav Falico 2013-09-25 09:20:07 +02:00 committed by David S. Miller
parent 7863c054d1
commit 2f268f129c
4 changed files with 129 additions and 114 deletions

View File

@ -1019,7 +1019,7 @@ static void alb_send_learning_packets(struct slave *slave, u8 mac_addr[])
/* loop through vlans and send one packet for each */
rcu_read_lock();
netdev_for_each_upper_dev_rcu(bond->dev, upper, iter) {
netdev_for_each_all_upper_dev_rcu(bond->dev, upper, iter) {
if (upper->priv_flags & IFF_802_1Q_VLAN)
alb_send_lp_vid(slave, mac_addr,
vlan_dev_vlan_id(upper));

View File

@ -2267,7 +2267,7 @@ static bool bond_has_this_ip(struct bonding *bond, __be32 ip)
return true;
rcu_read_lock();
netdev_for_each_upper_dev_rcu(bond->dev, upper, iter) {
netdev_for_each_all_upper_dev_rcu(bond->dev, upper, iter) {
if (ip == bond_confirm_addr(upper, 0, ip)) {
ret = true;
break;
@ -2342,10 +2342,12 @@ static void bond_arp_send_all(struct bonding *bond, struct slave *slave)
*
* TODO: QinQ?
*/
netdev_for_each_upper_dev_rcu(bond->dev, vlan_upper, vlan_iter) {
netdev_for_each_all_upper_dev_rcu(bond->dev, vlan_upper,
vlan_iter) {
if (!is_vlan_dev(vlan_upper))
continue;
netdev_for_each_upper_dev_rcu(vlan_upper, upper, iter) {
netdev_for_each_all_upper_dev_rcu(vlan_upper, upper,
iter) {
if (upper == rt->dst.dev) {
vlan_id = vlan_dev_vlan_id(vlan_upper);
rcu_read_unlock();
@ -2358,7 +2360,7 @@ static void bond_arp_send_all(struct bonding *bond, struct slave *slave)
* our upper vlans, then just search for any dev that
* matches, and in case it's a vlan - save the id
*/
netdev_for_each_upper_dev_rcu(bond->dev, upper, iter) {
netdev_for_each_all_upper_dev_rcu(bond->dev, upper, iter) {
if (upper == rt->dst.dev) {
/* if it's a vlan - get its VID */
if (is_vlan_dev(upper))

View File

@ -1143,8 +1143,18 @@ struct net_device {
struct list_head dev_list;
struct list_head napi_list;
struct list_head unreg_list;
struct list_head upper_dev_list; /* List of upper devices */
struct list_head lower_dev_list;
/* directly linked devices, like slaves for bonding */
struct {
struct list_head upper;
struct list_head lower;
} adj_list;
/* all linked devices, *including* neighbours */
struct {
struct list_head upper;
struct list_head lower;
} all_adj_list;
/* currently active device features */
@ -2813,15 +2823,15 @@ extern int bpf_jit_enable;
extern bool netdev_has_upper_dev(struct net_device *dev,
struct net_device *upper_dev);
extern bool netdev_has_any_upper_dev(struct net_device *dev);
extern struct net_device *netdev_upper_get_next_dev_rcu(struct net_device *dev,
struct list_head **iter);
extern struct net_device *netdev_all_upper_get_next_dev_rcu(struct net_device *dev,
struct list_head **iter);
/* iterate through upper list, must be called under RCU read lock */
#define netdev_for_each_upper_dev_rcu(dev, upper, iter) \
for (iter = &(dev)->upper_dev_list, \
upper = netdev_upper_get_next_dev_rcu(dev, &(iter)); \
upper; \
upper = netdev_upper_get_next_dev_rcu(dev, &(iter)))
#define netdev_for_each_all_upper_dev_rcu(dev, updev, iter) \
for (iter = &(dev)->all_adj_list.upper, \
updev = netdev_all_upper_get_next_dev_rcu(dev, &(iter)); \
updev; \
updev = netdev_all_upper_get_next_dev_rcu(dev, &(iter)))
extern struct net_device *netdev_master_upper_dev_get(struct net_device *dev);
extern struct net_device *netdev_master_upper_dev_get_rcu(struct net_device *dev);

View File

@ -4373,9 +4373,6 @@ struct netdev_adjacent {
/* upper master flag, there can only be one master device per list */
bool master;
/* indicates that this dev is our first-level lower/upper device */
bool neighbour;
/* counter for the number of times this device was added to us */
u16 ref_nr;
@ -4385,29 +4382,17 @@ struct netdev_adjacent {
static struct netdev_adjacent *__netdev_find_adj(struct net_device *dev,
struct net_device *adj_dev,
struct list_head *dev_list)
struct list_head *adj_list)
{
struct netdev_adjacent *adj;
list_for_each_entry(adj, dev_list, list) {
list_for_each_entry(adj, adj_list, list) {
if (adj->dev == adj_dev)
return adj;
}
return NULL;
}
static inline struct netdev_adjacent *__netdev_find_upper(struct net_device *dev,
struct net_device *udev)
{
return __netdev_find_adj(dev, udev, &dev->upper_dev_list);
}
static inline struct netdev_adjacent *__netdev_find_lower(struct net_device *dev,
struct net_device *ldev)
{
return __netdev_find_adj(dev, ldev, &dev->lower_dev_list);
}
/**
* netdev_has_upper_dev - Check if device is linked to an upper device
* @dev: device
@ -4422,7 +4407,7 @@ bool netdev_has_upper_dev(struct net_device *dev,
{
ASSERT_RTNL();
return __netdev_find_upper(dev, upper_dev);
return __netdev_find_adj(dev, upper_dev, &dev->all_adj_list.upper);
}
EXPORT_SYMBOL(netdev_has_upper_dev);
@ -4437,7 +4422,7 @@ bool netdev_has_any_upper_dev(struct net_device *dev)
{
ASSERT_RTNL();
return !list_empty(&dev->upper_dev_list);
return !list_empty(&dev->all_adj_list.upper);
}
EXPORT_SYMBOL(netdev_has_any_upper_dev);
@ -4454,10 +4439,10 @@ struct net_device *netdev_master_upper_dev_get(struct net_device *dev)
ASSERT_RTNL();
if (list_empty(&dev->upper_dev_list))
if (list_empty(&dev->adj_list.upper))
return NULL;
upper = list_first_entry(&dev->upper_dev_list,
upper = list_first_entry(&dev->adj_list.upper,
struct netdev_adjacent, list);
if (likely(upper->master))
return upper->dev;
@ -4465,15 +4450,15 @@ struct net_device *netdev_master_upper_dev_get(struct net_device *dev)
}
EXPORT_SYMBOL(netdev_master_upper_dev_get);
/* netdev_upper_get_next_dev_rcu - Get the next dev from upper list
/* netdev_all_upper_get_next_dev_rcu - Get the next dev from upper list
* @dev: device
* @iter: list_head ** of the current position
*
* Gets the next device from the dev's upper list, starting from iter
* position. The caller must hold RCU read lock.
*/
struct net_device *netdev_upper_get_next_dev_rcu(struct net_device *dev,
struct list_head **iter)
struct net_device *netdev_all_upper_get_next_dev_rcu(struct net_device *dev,
struct list_head **iter)
{
struct netdev_adjacent *upper;
@ -4481,14 +4466,14 @@ struct net_device *netdev_upper_get_next_dev_rcu(struct net_device *dev,
upper = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);
if (&upper->list == &dev->upper_dev_list)
if (&upper->list == &dev->all_adj_list.upper)
return NULL;
*iter = &upper->list;
return upper->dev;
}
EXPORT_SYMBOL(netdev_upper_get_next_dev_rcu);
EXPORT_SYMBOL(netdev_all_upper_get_next_dev_rcu);
/**
* netdev_master_upper_dev_get_rcu - Get master upper device
@ -4501,7 +4486,7 @@ struct net_device *netdev_master_upper_dev_get_rcu(struct net_device *dev)
{
struct netdev_adjacent *upper;
upper = list_first_or_null_rcu(&dev->upper_dev_list,
upper = list_first_or_null_rcu(&dev->adj_list.upper,
struct netdev_adjacent, list);
if (upper && likely(upper->master))
return upper->dev;
@ -4512,14 +4497,13 @@ EXPORT_SYMBOL(netdev_master_upper_dev_get_rcu);
static int __netdev_adjacent_dev_insert(struct net_device *dev,
struct net_device *adj_dev,
struct list_head *dev_list,
bool neighbour, bool master)
bool master)
{
struct netdev_adjacent *adj;
adj = __netdev_find_adj(dev, adj_dev, dev_list);
if (adj) {
BUG_ON(neighbour);
adj->ref_nr++;
return 0;
}
@ -4530,13 +4514,11 @@ static int __netdev_adjacent_dev_insert(struct net_device *dev,
adj->dev = adj_dev;
adj->master = master;
adj->neighbour = neighbour;
adj->ref_nr = 1;
dev_hold(adj_dev);
pr_debug("dev_hold for %s, because of %s link added from %s to %s\n",
adj_dev->name, dev_list == &dev->upper_dev_list ?
"upper" : "lower", dev->name, adj_dev->name);
pr_debug("dev_hold for %s, because of link added from %s to %s\n",
adj_dev->name, dev->name, adj_dev->name);
/* Ensure that master link is always the first item in list. */
if (master)
@ -4547,22 +4529,6 @@ static int __netdev_adjacent_dev_insert(struct net_device *dev,
return 0;
}
static inline int __netdev_upper_dev_insert(struct net_device *dev,
struct net_device *udev,
bool master, bool neighbour)
{
return __netdev_adjacent_dev_insert(dev, udev, &dev->upper_dev_list,
neighbour, master);
}
static inline int __netdev_lower_dev_insert(struct net_device *dev,
struct net_device *ldev,
bool neighbour)
{
return __netdev_adjacent_dev_insert(dev, ldev, &dev->lower_dev_list,
neighbour, false);
}
void __netdev_adjacent_dev_remove(struct net_device *dev,
struct net_device *adj_dev,
struct list_head *dev_list)
@ -4571,73 +4537,102 @@ void __netdev_adjacent_dev_remove(struct net_device *dev,
adj = __netdev_find_adj(dev, adj_dev, dev_list);
if (!adj)
if (!adj) {
pr_err("tried to remove device %s from %s\n",
dev->name, adj_dev->name);
BUG();
}
if (adj->ref_nr > 1) {
pr_debug("%s to %s ref_nr-- = %d\n", dev->name, adj_dev->name,
adj->ref_nr-1);
adj->ref_nr--;
return;
}
list_del_rcu(&adj->list);
pr_debug("dev_put for %s, because of %s link removed from %s to %s\n",
adj_dev->name, dev_list == &dev->upper_dev_list ?
"upper" : "lower", dev->name, adj_dev->name);
pr_debug("dev_put for %s, because link removed from %s to %s\n",
adj_dev->name, dev->name, adj_dev->name);
dev_put(adj_dev);
kfree_rcu(adj, rcu);
}
static inline void __netdev_upper_dev_remove(struct net_device *dev,
struct net_device *udev)
{
return __netdev_adjacent_dev_remove(dev, udev, &dev->upper_dev_list);
}
static inline void __netdev_lower_dev_remove(struct net_device *dev,
struct net_device *ldev)
{
return __netdev_adjacent_dev_remove(dev, ldev, &dev->lower_dev_list);
}
int __netdev_adjacent_dev_insert_link(struct net_device *dev,
struct net_device *upper_dev,
bool master, bool neighbour)
int __netdev_adjacent_dev_link_lists(struct net_device *dev,
struct net_device *upper_dev,
struct list_head *up_list,
struct list_head *down_list,
bool master)
{
int ret;
ret = __netdev_upper_dev_insert(dev, upper_dev, master, neighbour);
ret = __netdev_adjacent_dev_insert(dev, upper_dev, up_list, master);
if (ret)
return ret;
ret = __netdev_lower_dev_insert(upper_dev, dev, neighbour);
ret = __netdev_adjacent_dev_insert(upper_dev, dev, down_list, false);
if (ret) {
__netdev_upper_dev_remove(dev, upper_dev);
__netdev_adjacent_dev_remove(dev, upper_dev, up_list);
return ret;
}
return 0;
}
static inline int __netdev_adjacent_dev_link(struct net_device *dev,
struct net_device *udev)
int __netdev_adjacent_dev_link(struct net_device *dev,
struct net_device *upper_dev)
{
return __netdev_adjacent_dev_insert_link(dev, udev, false, false);
return __netdev_adjacent_dev_link_lists(dev, upper_dev,
&dev->all_adj_list.upper,
&upper_dev->all_adj_list.lower,
false);
}
static inline int __netdev_adjacent_dev_link_neighbour(struct net_device *dev,
struct net_device *udev,
bool master)
void __netdev_adjacent_dev_unlink_lists(struct net_device *dev,
struct net_device *upper_dev,
struct list_head *up_list,
struct list_head *down_list)
{
return __netdev_adjacent_dev_insert_link(dev, udev, master, true);
__netdev_adjacent_dev_remove(dev, upper_dev, up_list);
__netdev_adjacent_dev_remove(upper_dev, dev, down_list);
}
void __netdev_adjacent_dev_unlink(struct net_device *dev,
struct net_device *upper_dev)
{
__netdev_upper_dev_remove(dev, upper_dev);
__netdev_lower_dev_remove(upper_dev, dev);
__netdev_adjacent_dev_unlink_lists(dev, upper_dev,
&dev->all_adj_list.upper,
&upper_dev->all_adj_list.lower);
}
int __netdev_adjacent_dev_link_neighbour(struct net_device *dev,
struct net_device *upper_dev,
bool master)
{
int ret = __netdev_adjacent_dev_link(dev, upper_dev);
if (ret)
return ret;
ret = __netdev_adjacent_dev_link_lists(dev, upper_dev,
&dev->adj_list.upper,
&upper_dev->adj_list.lower,
master);
if (ret) {
__netdev_adjacent_dev_unlink(dev, upper_dev);
return ret;
}
return 0;
}
void __netdev_adjacent_dev_unlink_neighbour(struct net_device *dev,
struct net_device *upper_dev)
{
__netdev_adjacent_dev_unlink(dev, upper_dev);
__netdev_adjacent_dev_unlink_lists(dev, upper_dev,
&dev->adj_list.upper,
&upper_dev->adj_list.lower);
}
static int __netdev_upper_dev_link(struct net_device *dev,
struct net_device *upper_dev, bool master)
@ -4651,10 +4646,10 @@ static int __netdev_upper_dev_link(struct net_device *dev,
return -EBUSY;
/* To prevent loops, check if dev is not upper device to upper_dev. */
if (__netdev_find_upper(upper_dev, dev))
if (__netdev_find_adj(upper_dev, dev, &upper_dev->all_adj_list.upper))
return -EBUSY;
if (__netdev_find_upper(dev, upper_dev))
if (__netdev_find_adj(dev, upper_dev, &dev->all_adj_list.upper))
return -EEXIST;
if (master && netdev_master_upper_dev_get(dev))
@ -4665,12 +4660,14 @@ static int __netdev_upper_dev_link(struct net_device *dev,
return ret;
/* Now that we linked these devs, make all the upper_dev's
* upper_dev_list visible to every dev's lower_dev_list and vice
* all_adj_list.upper visible to every dev's all_adj_list.lower an
* versa, and don't forget the devices itself. All of these
* links are non-neighbours.
*/
list_for_each_entry(i, &dev->lower_dev_list, list) {
list_for_each_entry(j, &upper_dev->upper_dev_list, list) {
list_for_each_entry(i, &dev->all_adj_list.lower, list) {
list_for_each_entry(j, &upper_dev->all_adj_list.upper, list) {
pr_debug("Interlinking %s with %s, non-neighbour\n",
i->dev->name, j->dev->name);
ret = __netdev_adjacent_dev_link(i->dev, j->dev);
if (ret)
goto rollback_mesh;
@ -4678,14 +4675,18 @@ static int __netdev_upper_dev_link(struct net_device *dev,
}
/* add dev to every upper_dev's upper device */
list_for_each_entry(i, &upper_dev->upper_dev_list, list) {
list_for_each_entry(i, &upper_dev->all_adj_list.upper, list) {
pr_debug("linking %s's upper device %s with %s\n",
upper_dev->name, i->dev->name, dev->name);
ret = __netdev_adjacent_dev_link(dev, i->dev);
if (ret)
goto rollback_upper_mesh;
}
/* add upper_dev to every dev's lower device */
list_for_each_entry(i, &dev->lower_dev_list, list) {
list_for_each_entry(i, &dev->all_adj_list.lower, list) {
pr_debug("linking %s's lower device %s with %s\n", dev->name,
i->dev->name, upper_dev->name);
ret = __netdev_adjacent_dev_link(i->dev, upper_dev);
if (ret)
goto rollback_lower_mesh;
@ -4696,7 +4697,7 @@ static int __netdev_upper_dev_link(struct net_device *dev,
rollback_lower_mesh:
to_i = i;
list_for_each_entry(i, &dev->lower_dev_list, list) {
list_for_each_entry(i, &dev->all_adj_list.lower, list) {
if (i == to_i)
break;
__netdev_adjacent_dev_unlink(i->dev, upper_dev);
@ -4706,7 +4707,7 @@ rollback_lower_mesh:
rollback_upper_mesh:
to_i = i;
list_for_each_entry(i, &upper_dev->upper_dev_list, list) {
list_for_each_entry(i, &upper_dev->all_adj_list.upper, list) {
if (i == to_i)
break;
__netdev_adjacent_dev_unlink(dev, i->dev);
@ -4717,8 +4718,8 @@ rollback_upper_mesh:
rollback_mesh:
to_i = i;
to_j = j;
list_for_each_entry(i, &dev->lower_dev_list, list) {
list_for_each_entry(j, &upper_dev->upper_dev_list, list) {
list_for_each_entry(i, &dev->all_adj_list.lower, list) {
list_for_each_entry(j, &upper_dev->all_adj_list.upper, list) {
if (i == to_i && j == to_j)
break;
__netdev_adjacent_dev_unlink(i->dev, j->dev);
@ -4727,7 +4728,7 @@ rollback_mesh:
break;
}
__netdev_adjacent_dev_unlink(dev, upper_dev);
__netdev_adjacent_dev_unlink_neighbour(dev, upper_dev);
return ret;
}
@ -4781,23 +4782,23 @@ void netdev_upper_dev_unlink(struct net_device *dev,
struct netdev_adjacent *i, *j;
ASSERT_RTNL();
__netdev_adjacent_dev_unlink(dev, upper_dev);
__netdev_adjacent_dev_unlink_neighbour(dev, upper_dev);
/* Here is the tricky part. We must remove all dev's lower
* devices from all upper_dev's upper devices and vice
* versa, to maintain the graph relationship.
*/
list_for_each_entry(i, &dev->lower_dev_list, list)
list_for_each_entry(j, &upper_dev->upper_dev_list, list)
list_for_each_entry(i, &dev->all_adj_list.lower, list)
list_for_each_entry(j, &upper_dev->all_adj_list.upper, list)
__netdev_adjacent_dev_unlink(i->dev, j->dev);
/* remove also the devices itself from lower/upper device
* list
*/
list_for_each_entry(i, &dev->lower_dev_list, list)
list_for_each_entry(i, &dev->all_adj_list.lower, list)
__netdev_adjacent_dev_unlink(i->dev, upper_dev);
list_for_each_entry(i, &upper_dev->upper_dev_list, list)
list_for_each_entry(i, &upper_dev->all_adj_list.upper, list)
__netdev_adjacent_dev_unlink(dev, i->dev);
call_netdevice_notifiers(NETDEV_CHANGEUPPER, dev);
@ -6059,8 +6060,10 @@ struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name,
INIT_LIST_HEAD(&dev->napi_list);
INIT_LIST_HEAD(&dev->unreg_list);
INIT_LIST_HEAD(&dev->link_watch_list);
INIT_LIST_HEAD(&dev->upper_dev_list);
INIT_LIST_HEAD(&dev->lower_dev_list);
INIT_LIST_HEAD(&dev->adj_list.upper);
INIT_LIST_HEAD(&dev->adj_list.lower);
INIT_LIST_HEAD(&dev->all_adj_list.upper);
INIT_LIST_HEAD(&dev->all_adj_list.lower);
dev->priv_flags = IFF_XMIT_DST_RELEASE;
setup(dev);