net/mlx5e: Protect hairpin hash table with mutex

To remove dependency on rtnl lock, protect hairpin hash table from
concurrent modifications with new "hairpin_tbl_lock" mutex.

Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Reviewed-by: Roi Dayan <roid@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
This commit is contained in:
Vlad Buslov 2019-07-31 18:19:06 +03:00 committed by Saeed Mahameed
parent 73edca736e
commit b32accda8a
2 changed files with 18 additions and 4 deletions

View File

@ -17,6 +17,7 @@ struct mlx5e_tc_table {
struct rhashtable ht;
DECLARE_HASHTABLE(mod_hdr_tbl, 8);
struct mutex hairpin_tbl_lock; /* protects hairpin_tbl */
DECLARE_HASHTABLE(hairpin_tbl, 8);
struct notifier_block netdevice_nb;

View File

@ -652,15 +652,16 @@ static void mlx5e_hairpin_put(struct mlx5e_priv *priv,
struct mlx5e_hairpin_entry *hpe)
{
/* no more hairpin flows for us, release the hairpin pair */
if (!refcount_dec_and_test(&hpe->refcnt))
if (!refcount_dec_and_mutex_lock(&hpe->refcnt, &priv->fs.tc.hairpin_tbl_lock))
return;
hash_del(&hpe->hairpin_hlist);
mutex_unlock(&priv->fs.tc.hairpin_tbl_lock);
netdev_dbg(priv->netdev, "del hairpin: peer %s\n",
dev_name(hpe->hp->pair->peer_mdev->device));
WARN_ON(!list_empty(&hpe->flows));
mlx5e_hairpin_destroy(hpe->hp);
hash_del(&hpe->hairpin_hlist);
kfree(hpe);
}
@ -729,13 +730,17 @@ static int mlx5e_hairpin_flow_add(struct mlx5e_priv *priv,
extack);
if (err)
return err;
mutex_lock(&priv->fs.tc.hairpin_tbl_lock);
hpe = mlx5e_hairpin_get(priv, peer_id, match_prio);
if (hpe)
goto attach_flow;
hpe = kzalloc(sizeof(*hpe), GFP_KERNEL);
if (!hpe)
return -ENOMEM;
if (!hpe) {
err = -ENOMEM;
goto create_hairpin_err;
}
spin_lock_init(&hpe->flows_lock);
INIT_LIST_HEAD(&hpe->flows);
@ -784,6 +789,8 @@ static int mlx5e_hairpin_flow_add(struct mlx5e_priv *priv,
} else {
flow->nic_attr->hairpin_tirn = hpe->hp->tirn;
}
mutex_unlock(&priv->fs.tc.hairpin_tbl_lock);
flow->hpe = hpe;
spin_lock(&hpe->flows_lock);
list_add(&flow->hairpin, &hpe->flows);
@ -792,6 +799,7 @@ static int mlx5e_hairpin_flow_add(struct mlx5e_priv *priv,
return 0;
create_hairpin_err:
mutex_unlock(&priv->fs.tc.hairpin_tbl_lock);
kfree(hpe);
return err;
}
@ -3768,10 +3776,12 @@ static void mlx5e_tc_hairpin_update_dead_peer(struct mlx5e_priv *priv,
peer_vhca_id = MLX5_CAP_GEN(peer_mdev, vhca_id);
mutex_lock(&priv->fs.tc.hairpin_tbl_lock);
hash_for_each(priv->fs.tc.hairpin_tbl, bkt, hpe, hairpin_hlist) {
if (hpe->peer_vhca_id == peer_vhca_id)
hpe->hp->pair->peer_gone = true;
}
mutex_unlock(&priv->fs.tc.hairpin_tbl_lock);
}
static int mlx5e_tc_netdev_event(struct notifier_block *this,
@ -3808,6 +3818,7 @@ int mlx5e_tc_nic_init(struct mlx5e_priv *priv)
mutex_init(&tc->t_lock);
hash_init(tc->mod_hdr_tbl);
mutex_init(&tc->hairpin_tbl_lock);
hash_init(tc->hairpin_tbl);
err = rhashtable_init(&tc->ht, &tc_ht_params);
@ -3839,6 +3850,8 @@ void mlx5e_tc_nic_cleanup(struct mlx5e_priv *priv)
if (tc->netdevice_nb.notifier_call)
unregister_netdevice_notifier(&tc->netdevice_nb);
mutex_destroy(&tc->hairpin_tbl_lock);
rhashtable_destroy(&tc->ht);
if (!IS_ERR_OR_NULL(tc->t)) {