Skip to content

Commit

Permalink
vxlan: convert remotes list to list_rcu
Browse files Browse the repository at this point in the history 
Based on initial work by Mike Rapoport <mike.rapoport@ravellosystems.com>
Use list macros and RCU for tracking multiple remotes.

Note: this code assumes list always has at least one entry,
because delete is not supported.

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
  • Loading branch information
Stephen Hemminger committed Jun 24, 2013
1 parent 4ad1693 commit 3e61aa8
Showing 1 changed file with 55 additions and 42 deletions.
97 changes: 55 additions & 42 deletions drivers/net/vxlan.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -102,7 +102,7 @@ struct vxlan_rdst {
__be16 remote_port;
u32 remote_vni;
u32 remote_ifindex;
struct vxlan_rdst *remote_next;
struct list_head list;
};

/* Forwarding table entry */
Expand All @@ -111,7 +111,7 @@ struct vxlan_fdb {
struct rcu_head rcu;
unsigned long updated; /* jiffies */
unsigned long used;
struct vxlan_rdst remote;
struct list_head remotes;
u16 state; /* see ndm_state */
u8 flags; /* see ndm_flags */
u8 eth_addr[ETH_ALEN];
Expand Down Expand Up @@ -170,6 +170,14 @@ static inline struct hlist_head *vs_head(struct net *net, __be16 port)
return &vn->sock_list[hash_32(ntohs(port), PORT_HASH_BITS)];
}

/* First remote destination for a forwarding entry.
* Guaranteed to be non-NULL because remotes are never deleted.
*/
static inline struct vxlan_rdst *first_remote(struct vxlan_fdb *fdb)
{
return list_first_or_null_rcu(&fdb->remotes, struct vxlan_rdst, list);
}

/* Find VXLAN socket based on network namespace and UDP port */
static struct vxlan_sock *vxlan_find_port(struct net *net, __be16 port)
{
Expand Down Expand Up @@ -275,7 +283,7 @@ static inline size_t vxlan_nlmsg_size(void)
}

static void vxlan_fdb_notify(struct vxlan_dev *vxlan,
const struct vxlan_fdb *fdb, int type)
struct vxlan_fdb *fdb, int type)
{
struct net *net = dev_net(vxlan->dev);
struct sk_buff *skb;
Expand All @@ -285,7 +293,7 @@ static void vxlan_fdb_notify(struct vxlan_dev *vxlan,
if (skb == NULL)
goto errout;

err = vxlan_fdb_info(skb, vxlan, fdb, 0, 0, type, 0, &fdb->remote);
err = vxlan_fdb_info(skb, vxlan, fdb, 0, 0, type, 0, first_remote(fdb));
if (err < 0) {
/* -EMSGSIZE implies BUG in vxlan_nlmsg_size() */
WARN_ON(err == -EMSGSIZE);
Expand All @@ -304,11 +312,16 @@ static void vxlan_ip_miss(struct net_device *dev, __be32 ipa)
{
struct vxlan_dev *vxlan = netdev_priv(dev);
struct vxlan_fdb f;
struct vxlan_rdst remote;

memset(&f, 0, sizeof f);
f.state = NUD_STALE;
f.remote.remote_ip = ipa; /* goes to NDA_DST */
f.remote.remote_vni = VXLAN_N_VID;

remote.remote_ip = ipa; /* goes to NDA_DST */
remote.remote_vni = VXLAN_N_VID;

INIT_LIST_HEAD(&f.remotes);
list_add_rcu(&remote.list, &f.remotes);

vxlan_fdb_notify(vxlan, &f, RTM_GETNEIGH);
}
Expand All @@ -318,6 +331,7 @@ static void vxlan_fdb_miss(struct vxlan_dev *vxlan, const u8 eth_addr[ETH_ALEN])
struct vxlan_fdb f;

memset(&f, 0, sizeof f);
INIT_LIST_HEAD(&f.remotes);
f.state = NUD_STALE;
memcpy(f.eth_addr, eth_addr, ETH_ALEN);

Expand Down Expand Up @@ -377,26 +391,27 @@ static struct vxlan_fdb *vxlan_find_mac(struct vxlan_dev *vxlan,
static int vxlan_fdb_append(struct vxlan_fdb *f,
__be32 ip, __be16 port, __u32 vni, __u32 ifindex)
{
struct vxlan_rdst *rd_prev, *rd;
struct vxlan_rdst *rd;

rd_prev = NULL;
for (rd = &f->remote; rd; rd = rd->remote_next) {
/* protected by vxlan->hash_lock */
list_for_each_entry(rd, &f->remotes, list) {
if (rd->remote_ip == ip &&
rd->remote_port == port &&
rd->remote_vni == vni &&
rd->remote_ifindex == ifindex)
return 0;
rd_prev = rd;
}

rd = kmalloc(sizeof(*rd), GFP_ATOMIC);
if (rd == NULL)
return -ENOBUFS;
rd->remote_ip = ip;
rd->remote_port = port;
rd->remote_vni = vni;
rd->remote_ifindex = ifindex;
rd->remote_next = NULL;
rd_prev->remote_next = rd;

list_add_tail_rcu(&rd->list, &f->remotes);

return 1;
}

Expand Down Expand Up @@ -448,16 +463,14 @@ static int vxlan_fdb_create(struct vxlan_dev *vxlan,
return -ENOMEM;

notify = 1;
f->remote.remote_ip = ip;
f->remote.remote_port = port;
f->remote.remote_vni = vni;
f->remote.remote_ifindex = ifindex;
f->remote.remote_next = NULL;
f->state = state;
f->flags = ndm_flags;
f->updated = f->used = jiffies;
INIT_LIST_HEAD(&f->remotes);
memcpy(f->eth_addr, mac, ETH_ALEN);

vxlan_fdb_append(f, ip, port, vni, ifindex);

++vxlan->addrcnt;
hlist_add_head_rcu(&f->hlist,
vxlan_fdb_head(vxlan, mac));
Expand All @@ -472,13 +485,10 @@ static int vxlan_fdb_create(struct vxlan_dev *vxlan,
static void vxlan_fdb_free(struct rcu_head *head)
{
struct vxlan_fdb *f = container_of(head, struct vxlan_fdb, rcu);
struct vxlan_rdst *rd, *nd;

while (f->remote.remote_next) {
struct vxlan_rdst *rd = f->remote.remote_next;

f->remote.remote_next = rd->remote_next;
list_for_each_entry_safe(rd, nd, &f->remotes, list)
kfree(rd);
}
kfree(f);
}

Expand Down Expand Up @@ -588,23 +598,24 @@ static int vxlan_fdb_dump(struct sk_buff *skb, struct netlink_callback *cb,

hlist_for_each_entry_rcu(f, &vxlan->fdb_head[h], hlist) {
struct vxlan_rdst *rd;
for (rd = &f->remote; rd; rd = rd->remote_next) {
if (idx < cb->args[0])
goto skip;

if (idx < cb->args[0])
goto skip;

list_for_each_entry_rcu(rd, &f->remotes, list) {
err = vxlan_fdb_info(skb, vxlan, f,
NETLINK_CB(cb->skb).portid,
cb->nlh->nlmsg_seq,
RTM_NEWNEIGH,
NLM_F_MULTI, rd);
if (err < 0)
break;
skip:
++idx;
goto out;
}
skip:
++idx;
}
}

out:
return idx;
}

Expand All @@ -620,7 +631,9 @@ static bool vxlan_snoop(struct net_device *dev,

f = vxlan_find_mac(vxlan, src_mac);
if (likely(f)) {
if (likely(f->remote.remote_ip == src_ip))
struct vxlan_rdst *rdst = first_remote(f);

if (likely(rdst->remote_ip == src_ip))
return false;

/* Don't migrate static entries, drop packets */
Expand All @@ -630,9 +643,9 @@ static bool vxlan_snoop(struct net_device *dev,
if (net_ratelimit())
netdev_info(dev,
"%pM migrated from %pI4 to %pI4\n",
src_mac, &f->remote.remote_ip, &src_ip);
src_mac, &rdst->remote_ip, &src_ip);

f->remote.remote_ip = src_ip;
rdst->remote_ip = src_ip;
f->updated = jiffies;
vxlan_fdb_notify(vxlan, f, RTM_NEWNEIGH);
} else {
Expand Down Expand Up @@ -866,7 +879,7 @@ static int arp_reduce(struct net_device *dev, struct sk_buff *skb)
}

f = vxlan_find_mac(vxlan, n->ha);
if (f && f->remote.remote_ip == htonl(INADDR_ANY)) {
if (f && first_remote(f)->remote_ip == htonl(INADDR_ANY)) {
/* bridge-local neighbor */
neigh_release(n);
goto out;
Expand Down Expand Up @@ -1165,17 +1178,17 @@ static netdev_tx_t vxlan_xmit(struct sk_buff *skb, struct net_device *dev)
(vxlan->flags & VXLAN_F_L2MISS) &&
!is_multicast_ether_addr(eth->h_dest))
vxlan_fdb_miss(vxlan, eth->h_dest);
} else
rdst0 = &f->remote;

} else {
rdst = rdst0 = first_remote(f);

/* if there are multiple destinations, send copies */
for (rdst = rdst0->remote_next; rdst; rdst = rdst->remote_next) {
struct sk_buff *skb1;
/* if there are multiple destinations, send copies */
list_for_each_entry_continue_rcu(rdst, &f->remotes, list) {
struct sk_buff *skb1;

skb1 = skb_clone(skb, GFP_ATOMIC);
if (skb1)
vxlan_xmit_one(skb1, dev, rdst, did_rsc);
skb1 = skb_clone(skb, GFP_ATOMIC);
if (skb1)
vxlan_xmit_one(skb1, dev, rdst, did_rsc);
}
}

vxlan_xmit_one(skb, dev, rdst0, did_rsc);
Expand Down

0 comments on commit 3e61aa8

Please sign in to comment.