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vxlan: Use FDB_HASH_SIZE hash_locks to reduce contention
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The monolithic hash_lock could cause huge contention when
inserting/deletiing vxlan_fdbs into the fdb_head.

Use FDB_HASH_SIZE hash_locks to protect insertions/deletions
of vxlan_fdbs into the fdb_head hash table.

Suggested-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Litao jiao <jiaolitao@raisecom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Litao jiao authored and David S. Miller committed Jun 6, 2019
1 parent 4daa95a commit fe1e071
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Showing 2 changed files with 60 additions and 34 deletions.
92 changes: 59 additions & 33 deletions drivers/net/vxlan.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -471,14 +471,19 @@ static u32 eth_vni_hash(const unsigned char *addr, __be32 vni)
return jhash_2words(key, vni, vxlan_salt) & (FDB_HASH_SIZE - 1);
}

static u32 fdb_head_index(struct vxlan_dev *vxlan, const u8 *mac, __be32 vni)
{
if (vxlan->cfg.flags & VXLAN_F_COLLECT_METADATA)
return eth_vni_hash(mac, vni);
else
return eth_hash(mac);
}

/* Hash chain to use given mac address */
static inline struct hlist_head *vxlan_fdb_head(struct vxlan_dev *vxlan,
const u8 *mac, __be32 vni)
{
if (vxlan->cfg.flags & VXLAN_F_COLLECT_METADATA)
return &vxlan->fdb_head[eth_vni_hash(mac, vni)];
else
return &vxlan->fdb_head[eth_hash(mac)];
return &vxlan->fdb_head[fdb_head_index(vxlan, mac, vni)];
}

/* Look up Ethernet address in forwarding table */
Expand Down Expand Up @@ -593,23 +598,25 @@ int vxlan_fdb_replay(const struct net_device *dev, __be32 vni,
return -EINVAL;
vxlan = netdev_priv(dev);

spin_lock_bh(&vxlan->hash_lock);
for (h = 0; h < FDB_HASH_SIZE; ++h) {
spin_lock_bh(&vxlan->hash_lock[h]);
hlist_for_each_entry(f, &vxlan->fdb_head[h], hlist) {
if (f->vni == vni) {
list_for_each_entry(rdst, &f->remotes, list) {
rc = vxlan_fdb_notify_one(nb, vxlan,
f, rdst,
extack);
if (rc)
goto out;
goto unlock;
}
}
}
spin_unlock_bh(&vxlan->hash_lock[h]);
}
return 0;

out:
spin_unlock_bh(&vxlan->hash_lock);
unlock:
spin_unlock_bh(&vxlan->hash_lock[h]);
return rc;
}
EXPORT_SYMBOL_GPL(vxlan_fdb_replay);
Expand All @@ -625,14 +632,15 @@ void vxlan_fdb_clear_offload(const struct net_device *dev, __be32 vni)
return;
vxlan = netdev_priv(dev);

spin_lock_bh(&vxlan->hash_lock);
for (h = 0; h < FDB_HASH_SIZE; ++h) {
spin_lock_bh(&vxlan->hash_lock[h]);
hlist_for_each_entry(f, &vxlan->fdb_head[h], hlist)
if (f->vni == vni)
list_for_each_entry(rdst, &f->remotes, list)
rdst->offloaded = false;
spin_unlock_bh(&vxlan->hash_lock[h]);
}
spin_unlock_bh(&vxlan->hash_lock);

}
EXPORT_SYMBOL_GPL(vxlan_fdb_clear_offload);

Expand Down Expand Up @@ -1108,6 +1116,7 @@ static int vxlan_fdb_add(struct ndmsg *ndm, struct nlattr *tb[],
__be16 port;
__be32 src_vni, vni;
u32 ifindex;
u32 hash_index;
int err;

if (!(ndm->ndm_state & (NUD_PERMANENT|NUD_REACHABLE))) {
Expand All @@ -1126,12 +1135,13 @@ static int vxlan_fdb_add(struct ndmsg *ndm, struct nlattr *tb[],
if (vxlan->default_dst.remote_ip.sa.sa_family != ip.sa.sa_family)
return -EAFNOSUPPORT;

spin_lock_bh(&vxlan->hash_lock);
hash_index = fdb_head_index(vxlan, addr, src_vni);
spin_lock_bh(&vxlan->hash_lock[hash_index]);
err = vxlan_fdb_update(vxlan, addr, &ip, ndm->ndm_state, flags,
port, src_vni, vni, ifindex,
ndm->ndm_flags | NTF_VXLAN_ADDED_BY_USER,
true, extack);
spin_unlock_bh(&vxlan->hash_lock);
spin_unlock_bh(&vxlan->hash_lock[hash_index]);

return err;
}
Expand Down Expand Up @@ -1179,16 +1189,18 @@ static int vxlan_fdb_delete(struct ndmsg *ndm, struct nlattr *tb[],
__be32 src_vni, vni;
__be16 port;
u32 ifindex;
u32 hash_index;
int err;

err = vxlan_fdb_parse(tb, vxlan, &ip, &port, &src_vni, &vni, &ifindex);
if (err)
return err;

spin_lock_bh(&vxlan->hash_lock);
hash_index = fdb_head_index(vxlan, addr, src_vni);
spin_lock_bh(&vxlan->hash_lock[hash_index]);
err = __vxlan_fdb_delete(vxlan, addr, ip, port, src_vni, vni, ifindex,
true);
spin_unlock_bh(&vxlan->hash_lock);
spin_unlock_bh(&vxlan->hash_lock[hash_index]);

return err;
}
Expand Down Expand Up @@ -1300,8 +1312,10 @@ static bool vxlan_snoop(struct net_device *dev,
f->updated = jiffies;
vxlan_fdb_notify(vxlan, f, rdst, RTM_NEWNEIGH, true, NULL);
} else {
u32 hash_index = fdb_head_index(vxlan, src_mac, vni);

/* learned new entry */
spin_lock(&vxlan->hash_lock);
spin_lock(&vxlan->hash_lock[hash_index]);

/* close off race between vxlan_flush and incoming packets */
if (netif_running(dev))
Expand All @@ -1312,7 +1326,7 @@ static bool vxlan_snoop(struct net_device *dev,
vni,
vxlan->default_dst.remote_vni,
ifindex, NTF_SELF, true, NULL);
spin_unlock(&vxlan->hash_lock);
spin_unlock(&vxlan->hash_lock[hash_index]);
}

return false;
Expand Down Expand Up @@ -2702,7 +2716,7 @@ static void vxlan_cleanup(struct timer_list *t)
for (h = 0; h < FDB_HASH_SIZE; ++h) {
struct hlist_node *p, *n;

spin_lock(&vxlan->hash_lock);
spin_lock(&vxlan->hash_lock[h]);
hlist_for_each_safe(p, n, &vxlan->fdb_head[h]) {
struct vxlan_fdb *f
= container_of(p, struct vxlan_fdb, hlist);
Expand All @@ -2724,7 +2738,7 @@ static void vxlan_cleanup(struct timer_list *t)
} else if (time_before(timeout, next_timer))
next_timer = timeout;
}
spin_unlock(&vxlan->hash_lock);
spin_unlock(&vxlan->hash_lock[h]);
}

mod_timer(&vxlan->age_timer, next_timer);
Expand Down Expand Up @@ -2767,12 +2781,13 @@ static int vxlan_init(struct net_device *dev)
static void vxlan_fdb_delete_default(struct vxlan_dev *vxlan, __be32 vni)
{
struct vxlan_fdb *f;
u32 hash_index = fdb_head_index(vxlan, all_zeros_mac, vni);

spin_lock_bh(&vxlan->hash_lock);
spin_lock_bh(&vxlan->hash_lock[hash_index]);
f = __vxlan_find_mac(vxlan, all_zeros_mac, vni);
if (f)
vxlan_fdb_destroy(vxlan, f, true, true);
spin_unlock_bh(&vxlan->hash_lock);
spin_unlock_bh(&vxlan->hash_lock[hash_index]);
}

static void vxlan_uninit(struct net_device *dev)
Expand Down Expand Up @@ -2817,9 +2832,10 @@ static void vxlan_flush(struct vxlan_dev *vxlan, bool do_all)
{
unsigned int h;

spin_lock_bh(&vxlan->hash_lock);
for (h = 0; h < FDB_HASH_SIZE; ++h) {
struct hlist_node *p, *n;

spin_lock_bh(&vxlan->hash_lock[h]);
hlist_for_each_safe(p, n, &vxlan->fdb_head[h]) {
struct vxlan_fdb *f
= container_of(p, struct vxlan_fdb, hlist);
Expand All @@ -2829,8 +2845,8 @@ static void vxlan_flush(struct vxlan_dev *vxlan, bool do_all)
if (!is_zero_ether_addr(f->eth_addr))
vxlan_fdb_destroy(vxlan, f, true, true);
}
spin_unlock_bh(&vxlan->hash_lock[h]);
}
spin_unlock_bh(&vxlan->hash_lock);
}

/* Cleanup timer and forwarding table on shutdown */
Expand Down Expand Up @@ -3014,16 +3030,17 @@ static void vxlan_setup(struct net_device *dev)
dev->max_mtu = ETH_MAX_MTU;

INIT_LIST_HEAD(&vxlan->next);
spin_lock_init(&vxlan->hash_lock);

timer_setup(&vxlan->age_timer, vxlan_cleanup, TIMER_DEFERRABLE);

vxlan->dev = dev;

gro_cells_init(&vxlan->gro_cells, dev);

for (h = 0; h < FDB_HASH_SIZE; ++h)
for (h = 0; h < FDB_HASH_SIZE; ++h) {
spin_lock_init(&vxlan->hash_lock[h]);
INIT_HLIST_HEAD(&vxlan->fdb_head[h]);
}
}

static void vxlan_ether_setup(struct net_device *dev)
Expand Down Expand Up @@ -3917,7 +3934,9 @@ static int vxlan_changelink(struct net_device *dev, struct nlattr *tb[],

/* handle default dst entry */
if (!vxlan_addr_equal(&conf.remote_ip, &dst->remote_ip)) {
spin_lock_bh(&vxlan->hash_lock);
u32 hash_index = fdb_head_index(vxlan, all_zeros_mac, conf.vni);

spin_lock_bh(&vxlan->hash_lock[hash_index]);
if (!vxlan_addr_any(&conf.remote_ip)) {
err = vxlan_fdb_update(vxlan, all_zeros_mac,
&conf.remote_ip,
Expand All @@ -3928,7 +3947,7 @@ static int vxlan_changelink(struct net_device *dev, struct nlattr *tb[],
conf.remote_ifindex,
NTF_SELF, true, extack);
if (err) {
spin_unlock_bh(&vxlan->hash_lock);
spin_unlock_bh(&vxlan->hash_lock[hash_index]);
return err;
}
}
Expand All @@ -3940,7 +3959,7 @@ static int vxlan_changelink(struct net_device *dev, struct nlattr *tb[],
dst->remote_vni,
dst->remote_ifindex,
true);
spin_unlock_bh(&vxlan->hash_lock);
spin_unlock_bh(&vxlan->hash_lock[hash_index]);
}

if (conf.age_interval != vxlan->cfg.age_interval)
Expand Down Expand Up @@ -4195,8 +4214,11 @@ vxlan_fdb_offloaded_set(struct net_device *dev,
struct vxlan_dev *vxlan = netdev_priv(dev);
struct vxlan_rdst *rdst;
struct vxlan_fdb *f;
u32 hash_index;

hash_index = fdb_head_index(vxlan, fdb_info->eth_addr, fdb_info->vni);

spin_lock_bh(&vxlan->hash_lock);
spin_lock_bh(&vxlan->hash_lock[hash_index]);

f = vxlan_find_mac(vxlan, fdb_info->eth_addr, fdb_info->vni);
if (!f)
Expand All @@ -4212,7 +4234,7 @@ vxlan_fdb_offloaded_set(struct net_device *dev,
rdst->offloaded = fdb_info->offloaded;

out:
spin_unlock_bh(&vxlan->hash_lock);
spin_unlock_bh(&vxlan->hash_lock[hash_index]);
}

static int
Expand All @@ -4221,11 +4243,13 @@ vxlan_fdb_external_learn_add(struct net_device *dev,
{
struct vxlan_dev *vxlan = netdev_priv(dev);
struct netlink_ext_ack *extack;
u32 hash_index;
int err;

hash_index = fdb_head_index(vxlan, fdb_info->eth_addr, fdb_info->vni);
extack = switchdev_notifier_info_to_extack(&fdb_info->info);

spin_lock_bh(&vxlan->hash_lock);
spin_lock_bh(&vxlan->hash_lock[hash_index]);
err = vxlan_fdb_update(vxlan, fdb_info->eth_addr, &fdb_info->remote_ip,
NUD_REACHABLE,
NLM_F_CREATE | NLM_F_REPLACE,
Expand All @@ -4235,7 +4259,7 @@ vxlan_fdb_external_learn_add(struct net_device *dev,
fdb_info->remote_ifindex,
NTF_USE | NTF_SELF | NTF_EXT_LEARNED,
false, extack);
spin_unlock_bh(&vxlan->hash_lock);
spin_unlock_bh(&vxlan->hash_lock[hash_index]);

return err;
}
Expand All @@ -4246,9 +4270,11 @@ vxlan_fdb_external_learn_del(struct net_device *dev,
{
struct vxlan_dev *vxlan = netdev_priv(dev);
struct vxlan_fdb *f;
u32 hash_index;
int err = 0;

spin_lock_bh(&vxlan->hash_lock);
hash_index = fdb_head_index(vxlan, fdb_info->eth_addr, fdb_info->vni);
spin_lock_bh(&vxlan->hash_lock[hash_index]);

f = vxlan_find_mac(vxlan, fdb_info->eth_addr, fdb_info->vni);
if (!f)
Expand All @@ -4262,7 +4288,7 @@ vxlan_fdb_external_learn_del(struct net_device *dev,
fdb_info->remote_ifindex,
false);

spin_unlock_bh(&vxlan->hash_lock);
spin_unlock_bh(&vxlan->hash_lock[hash_index]);

return err;
}
Expand Down
2 changes: 1 addition & 1 deletion include/net/vxlan.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -242,7 +242,7 @@ struct vxlan_dev {
struct vxlan_rdst default_dst; /* default destination */

struct timer_list age_timer;
spinlock_t hash_lock;
spinlock_t hash_lock[FDB_HASH_SIZE];
unsigned int addrcnt;
struct gro_cells gro_cells;

Expand Down

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