[PATCH net-next 09/11] net: Remove all_adj_list and its references

David Ahern
2016-10-15T01:28:49Z

Only direct adjacencies are maintained. All upper or lower devices can
be learned via the new walk API which recursively walks the adj_list for
upper devices or lower devices.

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
---
include/linux/netdevice.h | 25 -----
net/core/dev.c | 229 +++++-----------------------------------------
2 files changed, 21 insertions(+), 233 deletions(-)

diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index a5902d995907..458c87631e7f 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -1456,7 +1456,6 @@ enum netdev_priv_flags {
* @ptype_specific: Device-specific, protocol-specific packet handlers
*
* @adj_list: Directly linked devices, like slaves for bonding
- * @all_adj_list: All linked devices, *including* neighbours
* @features: Currently active device features
* @hw_features: User-changeable features
*
@@ -1675,11 +1674,6 @@ struct net_device {
struct list_head lower;
} adj_list;

- struct {
- struct list_head upper;
- struct list_head lower;
- } all_adj_list;
-
netdev_features_t features;
netdev_features_t hw_features;
netdev_features_t wanted_features;
@@ -3771,13 +3765,6 @@ struct net_device *netdev_all_upper_get_next_dev_rcu(struct net_device *dev,
updev; \
updev = netdev_upper_get_next_dev_rcu(dev, &(iter)))

-/* iterate through upper list, must be called under RCU read lock */
-#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)))
-
int netdev_walk_all_upper_dev_rcu(struct net_device *dev,
int (*fn)(struct net_device *upper_dev,
void *data),
@@ -3817,18 +3804,6 @@ struct net_device *netdev_all_lower_get_next(struct net_device *dev,
struct net_device *netdev_all_lower_get_next_rcu(struct net_device *dev,
struct list_head **iter);

-#define netdev_for_each_all_lower_dev(dev, ldev, iter) \
- for (iter = (dev)->all_adj_list.lower.next, \
- ldev = netdev_all_lower_get_next(dev, &(iter)); \
- ldev; \
- ldev = netdev_all_lower_get_next(dev, &(iter)))
-
-#define netdev_for_each_all_lower_dev_rcu(dev, ldev, iter) \
- for (iter = (dev)->all_adj_list.lower.next, \
- ldev = netdev_all_lower_get_next_rcu(dev, &(iter)); \
- ldev; \
- ldev = netdev_all_lower_get_next_rcu(dev, &(iter)))
-
int netdev_walk_all_lower_dev(struct net_device *dev,
int (*fn)(struct net_device *lower_dev,
void *data),
diff --git a/net/core/dev.c b/net/core/dev.c
index 1780f94ed25f..a012c7266230 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -5137,6 +5137,16 @@ static struct netdev_adjacent *__netdev_find_adj(struct net_device *adj_dev,
return NULL;
}

+static int __netdev_has_upper_dev(struct net_device *upper_dev, void *data)
+{
+ struct net_device *dev = (struct net_device *)data;
+
+ if (upper_dev == dev)
+ return 1;
+
+ return 0;
+}
+
/**
* netdev_has_upper_dev - Check if device is linked to an upper device
* @dev: device
@@ -5151,7 +5161,8 @@ bool netdev_has_upper_dev(struct net_device *dev,
{
ASSERT_RTNL();

- return __netdev_find_adj(upper_dev, &dev->all_adj_list.upper);
+ return netdev_walk_all_upper_dev_rcu(dev, __netdev_has_upper_dev,
+ upper_dev);
}
EXPORT_SYMBOL(netdev_has_upper_dev);

@@ -5165,16 +5176,6 @@ EXPORT_SYMBOL(netdev_has_upper_dev);
* The caller must hold rcu lock.
*/

-static int __netdev_has_upper_dev(struct net_device *upper_dev, void *data)
-{
- struct net_device *dev = (struct net_device *)data;
-
- if (upper_dev == dev)
- return 1;
-
- return 0;
-}
-
bool netdev_has_upper_dev_all_rcu(struct net_device *dev,
struct net_device *upper_dev)
{
@@ -5197,7 +5198,7 @@ static bool netdev_has_any_upper_dev(struct net_device *dev)
{
ASSERT_RTNL();

- return !list_empty(&dev->all_adj_list.upper);
+ return !list_empty(&dev->adj_list.upper);
}

/**
@@ -5260,32 +5261,6 @@ struct net_device *netdev_upper_get_next_dev_rcu(struct net_device *dev,
}
EXPORT_SYMBOL(netdev_upper_get_next_dev_rcu);

-/**
- * 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_all_upper_get_next_dev_rcu(struct net_device *dev,
- struct list_head **iter)
-{
- struct netdev_adjacent *upper;
-
- WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_rtnl_is_held());
-
- upper = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);
-
- if (&upper->list == &dev->all_adj_list.upper)
- return NULL;
-
- *iter = &upper->list;
-
- return upper->dev;
-}
-EXPORT_SYMBOL(netdev_all_upper_get_next_dev_rcu);
-
static struct net_device *netdev_next_upper_dev_rcu(struct net_device *dev,
struct list_head **iter)
{
@@ -5412,31 +5387,6 @@ void *netdev_lower_get_next(struct net_device *dev, struct list_head **iter)
}
EXPORT_SYMBOL(netdev_lower_get_next);

-/**
- * netdev_all_lower_get_next - Get the next device from all lower neighbour list
- * @dev: device
- * @iter: list_head ** of the current position
- *
- * Gets the next netdev_adjacent from the dev's all lower neighbour
- * list, starting from iter position. The caller must hold RTNL lock or
- * its own locking that guarantees that the neighbour all lower
- * list will remain unchanged.
- */
-struct net_device *netdev_all_lower_get_next(struct net_device *dev, struct list_head **iter)
-{
- struct netdev_adjacent *lower;
-
- lower = list_entry(*iter, struct netdev_adjacent, list);
-
- if (&lower->list == &dev->all_adj_list.lower)
- return NULL;
-
- *iter = lower->list.next;
-
- return lower->dev;
-}
-EXPORT_SYMBOL(netdev_all_lower_get_next);
-
static struct net_device *netdev_next_lower_dev(struct net_device *dev,
struct list_head **iter)
{
@@ -5480,27 +5430,6 @@ int netdev_walk_all_lower_dev(struct net_device *dev,
}
EXPORT_SYMBOL_GPL(netdev_walk_all_lower_dev);

-/**
- * netdev_all_lower_get_next_rcu - Get the next device from all
- * lower neighbour list, RCU variant
- * @dev: device
- * @iter: list_head ** of the current position
- *
- * Gets the next netdev_adjacent from the dev's all lower neighbour
- * list, starting from iter position. The caller must hold RCU read lock.
- */
-struct net_device *netdev_all_lower_get_next_rcu(struct net_device *dev,
- struct list_head **iter)
-{
- struct netdev_adjacent *lower;
-
- lower = list_first_or_null_rcu(&dev->all_adj_list.lower,
- struct netdev_adjacent, list);
-
- return lower ? lower->dev : NULL;
-}
-EXPORT_SYMBOL(netdev_all_lower_get_next_rcu);
-
static struct net_device *netdev_next_lower_dev_rcu(struct net_device *dev,
struct list_head **iter)
{
@@ -5728,15 +5657,6 @@ static int __netdev_adjacent_dev_link_lists(struct net_device *dev,
return 0;
}

-static int __netdev_adjacent_dev_link(struct net_device *dev,
- struct net_device *upper_dev)
-{
- return __netdev_adjacent_dev_link_lists(dev, upper_dev,
- &dev->all_adj_list.upper,
- &upper_dev->all_adj_list.lower,
- NULL, false);
-}
-
static void __netdev_adjacent_dev_unlink_lists(struct net_device *dev,
struct net_device *upper_dev,
u16 ref_nr,
@@ -5747,40 +5667,19 @@ static void __netdev_adjacent_dev_unlink_lists(struct net_device *dev,
__netdev_adjacent_dev_remove(upper_dev, dev, ref_nr, down_list);
}

-static void __netdev_adjacent_dev_unlink(struct net_device *dev,
- struct net_device *upper_dev,
- u16 ref_nr)
-{
- __netdev_adjacent_dev_unlink_lists(dev, upper_dev, ref_nr,
- &dev->all_adj_list.upper,
- &upper_dev->all_adj_list.lower);
-}
-
static int __netdev_adjacent_dev_link_neighbour(struct net_device *dev,
struct net_device *upper_dev,
void *private, 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,
- private, master);
- if (ret) {
- __netdev_adjacent_dev_unlink(dev, upper_dev, 1);
- return ret;
- }
-
- return 0;
+ return __netdev_adjacent_dev_link_lists(dev, upper_dev,
+ &dev->adj_list.upper,
+ &upper_dev->adj_list.lower,
+ private, master);
}

static void __netdev_adjacent_dev_unlink_neighbour(struct net_device *dev,
struct net_device *upper_dev)
{
- __netdev_adjacent_dev_unlink(dev, upper_dev, 1);
__netdev_adjacent_dev_unlink_lists(dev, upper_dev, 1,
&dev->adj_list.upper,
&upper_dev->adj_list.lower);
@@ -5791,7 +5690,6 @@ static int __netdev_upper_dev_link(struct net_device *dev,
void *upper_priv, void *upper_info)
{
struct netdev_notifier_changeupper_info changeupper_info;
- struct netdev_adjacent *i, *j, *to_i, *to_j;
int ret = 0;

ASSERT_RTNL();
@@ -5800,10 +5698,10 @@ 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_adj(dev, &upper_dev->all_adj_list.upper))
+ if (netdev_has_upper_dev(upper_dev, dev))
return -EBUSY;

- if (__netdev_find_adj(upper_dev, &dev->adj_list.upper))
+ if (netdev_has_upper_dev(dev, upper_dev))
return -EEXIST;

if (master && netdev_master_upper_dev_get(dev))
@@ -5825,80 +5723,15 @@ static int __netdev_upper_dev_link(struct net_device *dev,
if (ret)
return ret;

- /* Now that we linked these devs, make all the upper_dev's
- * 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->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;
- }
- }
-
- /* add dev to every upper_dev's upper device */
- 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->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;
- }
-
ret = call_netdevice_notifiers_info(NETDEV_CHANGEUPPER, dev,
&changeupper_info.info);
ret = notifier_to_errno(ret);
if (ret)
- goto rollback_lower_mesh;
+ goto rollback;

return 0;

-rollback_lower_mesh:
- to_i = i;
- list_for_each_entry(i, &dev->all_adj_list.lower, list) {
- if (i == to_i)
- break;
- __netdev_adjacent_dev_unlink(i->dev, upper_dev, i->ref_nr);
- }
-
- i = NULL;
-
-rollback_upper_mesh:
- to_i = i;
- list_for_each_entry(i, &upper_dev->all_adj_list.upper, list) {
- if (i == to_i)
- break;
- __netdev_adjacent_dev_unlink(dev, i->dev, i->ref_nr);
- }
-
- i = j = NULL;
-
-rollback_mesh:
- to_i = i;
- to_j = j;
- 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, i->ref_nr);
- }
- if (i == to_i)
- break;
- }
-
+rollback:
__netdev_adjacent_dev_unlink_neighbour(dev, upper_dev);

return ret;
@@ -5955,7 +5788,6 @@ void netdev_upper_dev_unlink(struct net_device *dev,
struct net_device *upper_dev)
{
struct netdev_notifier_changeupper_info changeupper_info;
- struct netdev_adjacent *i, *j;
ASSERT_RTNL();

changeupper_info.upper_dev = upper_dev;
@@ -5967,23 +5799,6 @@ void netdev_upper_dev_unlink(struct net_device *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->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, i->ref_nr);
-
- /* remove also the devices itself from lower/upper device
- * list
- */
- list_for_each_entry(i, &dev->all_adj_list.lower, list)
- __netdev_adjacent_dev_unlink(i->dev, upper_dev, i->ref_nr);
-
- list_for_each_entry(i, &upper_dev->all_adj_list.upper, list)
- __netdev_adjacent_dev_unlink(dev, i->dev, i->ref_nr);
-
call_netdevice_notifiers_info(NETDEV_CHANGEUPPER, dev,
&changeupper_info.info);
}
@@ -7685,8 +7500,6 @@ struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name,
INIT_LIST_HEAD(&dev->link_watch_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);
INIT_LIST_HEAD(&dev->ptype_all);
INIT_LIST_HEAD(&dev->ptype_specific);
#ifdef CONFIG_NET_SCHED
--
2.1.4