From 359a587c6c74c1e86ac5e9446edd6eaf950b7f52 Mon Sep 17 00:00:00 2001 From: Vlad Buslov Date: Sun, 20 Sep 2020 12:43:58 +0300 Subject: [PATCH] net/mlx5e: Refactor neigh update infrastructure Following patches in series implements route update which can cause encap entries to migrate between routing devices. Consecutively, their parent nhe's need to be also transferable between devices instead of having neigh device as a part of their immutable key. Move neigh device from struct mlx5_neigh to struct mlx5e_neigh_hash_entry and check that nhe and neigh devices are the same in workqueue neigh update handler. Save neigh net_device that can change dynamically in dedicated nhe->dev field. With FIB event handler that is implemented in following patches changing nhe->dev, NETEVENT_DELAY_PROBE_TIME_UPDATE handler can concurrently access the nhe entry when traversing neigh list under rcu read lock. Processing stale values in that handler doesn't change the handler logic, so just wrap all accesses to the dev pointer in {WRITE|READ}_ONCE() helpers. Signed-off-by: Vlad Buslov Signed-off-by: Dmytro Linkin Reviewed-by: Roi Dayan Signed-off-by: Saeed Mahameed --- .../mlx5/core/diag/en_rep_tracepoint.h | 4 ++-- .../mlx5/core/diag/en_tc_tracepoint.h | 4 ++-- .../mellanox/mlx5/core/en/rep/neigh.c | 16 +++++++++----- .../mellanox/mlx5/core/en/rep/neigh.h | 3 ++- .../ethernet/mellanox/mlx5/core/en/rep/tc.c | 8 ++++--- .../ethernet/mellanox/mlx5/core/en/rep/tc.h | 4 +++- .../ethernet/mellanox/mlx5/core/en/tc_tun.c | 22 +++++++------------ .../mellanox/mlx5/core/en/tc_tun_encap.c | 2 +- .../net/ethernet/mellanox/mlx5/core/en_rep.h | 3 +-- 9 files changed, 35 insertions(+), 31 deletions(-) diff --git a/drivers/net/ethernet/mellanox/mlx5/core/diag/en_rep_tracepoint.h b/drivers/net/ethernet/mellanox/mlx5/core/diag/en_rep_tracepoint.h index 1177860a2ee48..f15718db5d0ee 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/diag/en_rep_tracepoint.h +++ b/drivers/net/ethernet/mellanox/mlx5/core/diag/en_rep_tracepoint.h @@ -15,7 +15,7 @@ TRACE_EVENT(mlx5e_rep_neigh_update, TP_PROTO(const struct mlx5e_neigh_hash_entry *nhe, const u8 *ha, bool neigh_connected), TP_ARGS(nhe, ha, neigh_connected), - TP_STRUCT__entry(__string(devname, nhe->m_neigh.dev->name) + TP_STRUCT__entry(__string(devname, nhe->neigh_dev->name) __array(u8, ha, ETH_ALEN) __array(u8, v4, 4) __array(u8, v6, 16) @@ -25,7 +25,7 @@ TRACE_EVENT(mlx5e_rep_neigh_update, struct in6_addr *pin6; __be32 *p32; - __assign_str(devname, mn->dev->name); + __assign_str(devname, nhe->neigh_dev->name); __entry->neigh_connected = neigh_connected; memcpy(__entry->ha, ha, ETH_ALEN); diff --git a/drivers/net/ethernet/mellanox/mlx5/core/diag/en_tc_tracepoint.h b/drivers/net/ethernet/mellanox/mlx5/core/diag/en_tc_tracepoint.h index d4e6cfaaade37..ac52ef37f38a8 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/diag/en_tc_tracepoint.h +++ b/drivers/net/ethernet/mellanox/mlx5/core/diag/en_tc_tracepoint.h @@ -77,7 +77,7 @@ TRACE_EVENT(mlx5e_stats_flower, TRACE_EVENT(mlx5e_tc_update_neigh_used_value, TP_PROTO(const struct mlx5e_neigh_hash_entry *nhe, bool neigh_used), TP_ARGS(nhe, neigh_used), - TP_STRUCT__entry(__string(devname, nhe->m_neigh.dev->name) + TP_STRUCT__entry(__string(devname, nhe->neigh_dev->name) __array(u8, v4, 4) __array(u8, v6, 16) __field(bool, neigh_used) @@ -86,7 +86,7 @@ TRACE_EVENT(mlx5e_tc_update_neigh_used_value, struct in6_addr *pin6; __be32 *p32; - __assign_str(devname, mn->dev->name); + __assign_str(devname, nhe->neigh_dev->name); __entry->neigh_used = neigh_used; p32 = (__be32 *)__entry->v4; diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/rep/neigh.c b/drivers/net/ethernet/mellanox/mlx5/core/en/rep/neigh.c index 616ee585a9855..be0ee03de7217 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en/rep/neigh.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/en/rep/neigh.c @@ -129,10 +129,10 @@ static void mlx5e_rep_neigh_update(struct work_struct *work) work); struct mlx5e_neigh_hash_entry *nhe = update_work->nhe; struct neighbour *n = update_work->n; + bool neigh_connected, same_dev; struct mlx5e_encap_entry *e; unsigned char ha[ETH_ALEN]; struct mlx5e_priv *priv; - bool neigh_connected; u8 nud_state, dead; rtnl_lock(); @@ -146,12 +146,16 @@ static void mlx5e_rep_neigh_update(struct work_struct *work) memcpy(ha, n->ha, ETH_ALEN); nud_state = n->nud_state; dead = n->dead; + same_dev = READ_ONCE(nhe->neigh_dev) == n->dev; read_unlock_bh(&n->lock); neigh_connected = (nud_state & NUD_VALID) && !dead; trace_mlx5e_rep_neigh_update(nhe, ha, neigh_connected); + if (!same_dev) + goto out; + list_for_each_entry(e, &nhe->encap_list, encap_list) { if (!mlx5e_encap_take(e)) continue; @@ -160,6 +164,7 @@ static void mlx5e_rep_neigh_update(struct work_struct *work) mlx5e_rep_update_flows(priv, e, neigh_connected, ha); mlx5e_encap_put(priv, e); } +out: rtnl_unlock(); mlx5e_release_neigh_update_work(update_work); } @@ -175,7 +180,6 @@ static struct neigh_update_work *mlx5e_alloc_neigh_update_work(struct mlx5e_priv if (WARN_ON(!update_work)) return NULL; - m_neigh.dev = n->dev; m_neigh.family = n->ops->family; memcpy(&m_neigh.dst_ip, n->primary_key, n->tbl->key_len); @@ -246,7 +250,7 @@ static int mlx5e_rep_netevent_event(struct notifier_block *nb, rcu_read_lock(); list_for_each_entry_rcu(nhe, &neigh_update->neigh_list, neigh_list) { - if (p->dev == nhe->m_neigh.dev) { + if (p->dev == READ_ONCE(nhe->neigh_dev)) { found = true; break; } @@ -369,7 +373,8 @@ mlx5e_rep_neigh_entry_lookup(struct mlx5e_priv *priv, } int mlx5e_rep_neigh_entry_create(struct mlx5e_priv *priv, - struct mlx5e_encap_entry *e, + struct mlx5e_neigh *m_neigh, + struct net_device *neigh_dev, struct mlx5e_neigh_hash_entry **nhe) { int err; @@ -379,10 +384,11 @@ int mlx5e_rep_neigh_entry_create(struct mlx5e_priv *priv, return -ENOMEM; (*nhe)->priv = priv; - memcpy(&(*nhe)->m_neigh, &e->m_neigh, sizeof(e->m_neigh)); + memcpy(&(*nhe)->m_neigh, m_neigh, sizeof(*m_neigh)); spin_lock_init(&(*nhe)->encap_list_lock); INIT_LIST_HEAD(&(*nhe)->encap_list); refcount_set(&(*nhe)->refcnt, 1); + WRITE_ONCE((*nhe)->neigh_dev, neigh_dev); err = mlx5e_rep_neigh_entry_insert(priv, *nhe); if (err) diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/rep/neigh.h b/drivers/net/ethernet/mellanox/mlx5/core/en/rep/neigh.h index 32b239189c95b..6fe0ab9709432 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en/rep/neigh.h +++ b/drivers/net/ethernet/mellanox/mlx5/core/en/rep/neigh.h @@ -16,7 +16,8 @@ struct mlx5e_neigh_hash_entry * mlx5e_rep_neigh_entry_lookup(struct mlx5e_priv *priv, struct mlx5e_neigh *m_neigh); int mlx5e_rep_neigh_entry_create(struct mlx5e_priv *priv, - struct mlx5e_encap_entry *e, + struct mlx5e_neigh *m_neigh, + struct net_device *neigh_dev, struct mlx5e_neigh_hash_entry **nhe); void mlx5e_rep_neigh_entry_release(struct mlx5e_neigh_hash_entry *nhe); diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/rep/tc.c b/drivers/net/ethernet/mellanox/mlx5/core/en/rep/tc.c index 14bcebd4a0b61..a7ba1c84371df 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en/rep/tc.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/en/rep/tc.c @@ -26,7 +26,9 @@ struct mlx5e_rep_indr_block_priv { }; int mlx5e_rep_encap_entry_attach(struct mlx5e_priv *priv, - struct mlx5e_encap_entry *e) + struct mlx5e_encap_entry *e, + struct mlx5e_neigh *m_neigh, + struct net_device *neigh_dev) { struct mlx5e_rep_priv *rpriv = priv->ppriv; struct mlx5_rep_uplink_priv *uplink_priv = &rpriv->uplink_priv; @@ -39,9 +41,9 @@ int mlx5e_rep_encap_entry_attach(struct mlx5e_priv *priv, return err; mutex_lock(&rpriv->neigh_update.encap_lock); - nhe = mlx5e_rep_neigh_entry_lookup(priv, &e->m_neigh); + nhe = mlx5e_rep_neigh_entry_lookup(priv, m_neigh); if (!nhe) { - err = mlx5e_rep_neigh_entry_create(priv, e, &nhe); + err = mlx5e_rep_neigh_entry_create(priv, m_neigh, neigh_dev, &nhe); if (err) { mutex_unlock(&rpriv->neigh_update.encap_lock); mlx5_tun_entropy_refcount_dec(tun_entropy, diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/rep/tc.h b/drivers/net/ethernet/mellanox/mlx5/core/en/rep/tc.h index fdf9702c2d7dc..d0661578467be 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en/rep/tc.h +++ b/drivers/net/ethernet/mellanox/mlx5/core/en/rep/tc.h @@ -27,7 +27,9 @@ void mlx5e_rep_update_flows(struct mlx5e_priv *priv, unsigned char ha[ETH_ALEN]); int mlx5e_rep_encap_entry_attach(struct mlx5e_priv *priv, - struct mlx5e_encap_entry *e); + struct mlx5e_encap_entry *e, + struct mlx5e_neigh *m_neigh, + struct net_device *neigh_dev); void mlx5e_rep_encap_entry_detach(struct mlx5e_priv *priv, struct mlx5e_encap_entry *e); diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/tc_tun.c b/drivers/net/ethernet/mellanox/mlx5/core/en/tc_tun.c index def2335c39e45..0ad22f5709a1d 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en/tc_tun.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/en/tc_tun.c @@ -212,6 +212,7 @@ int mlx5e_tc_tun_create_header_ipv4(struct mlx5e_priv *priv, { int max_encap_size = MLX5_CAP_ESW(priv->mdev, max_encap_header_size); const struct ip_tunnel_key *tun_key = &e->tun_info->key; + struct mlx5e_neigh m_neigh = {}; TC_TUN_ROUTE_ATTR_INIT(attr); int ipv4_encap_size; char *encap_header; @@ -247,12 +248,8 @@ int mlx5e_tc_tun_create_header_ipv4(struct mlx5e_priv *priv, goto release_neigh; } - /* used by mlx5e_detach_encap to lookup a neigh hash table - * entry in the neigh hash table when a user deletes a rule - */ - e->m_neigh.dev = attr.n->dev; - e->m_neigh.family = attr.n->ops->family; - memcpy(&e->m_neigh.dst_ip, attr.n->primary_key, attr.n->tbl->key_len); + m_neigh.family = attr.n->ops->family; + memcpy(&m_neigh.dst_ip, attr.n->primary_key, attr.n->tbl->key_len); e->out_dev = attr.out_dev; e->route_dev_ifindex = attr.route_dev->ifindex; @@ -261,7 +258,7 @@ int mlx5e_tc_tun_create_header_ipv4(struct mlx5e_priv *priv, * neigh changes it's validity state, we would find the relevant neigh * in the hash. */ - err = mlx5e_rep_encap_entry_attach(netdev_priv(attr.out_dev), e); + err = mlx5e_rep_encap_entry_attach(netdev_priv(attr.out_dev), e, &m_neigh, attr.n->dev); if (err) goto free_encap; @@ -375,6 +372,7 @@ int mlx5e_tc_tun_create_header_ipv6(struct mlx5e_priv *priv, { int max_encap_size = MLX5_CAP_ESW(priv->mdev, max_encap_header_size); const struct ip_tunnel_key *tun_key = &e->tun_info->key; + struct mlx5e_neigh m_neigh = {}; TC_TUN_ROUTE_ATTR_INIT(attr); struct ipv6hdr *ip6h; int ipv6_encap_size; @@ -409,12 +407,8 @@ int mlx5e_tc_tun_create_header_ipv6(struct mlx5e_priv *priv, goto release_neigh; } - /* used by mlx5e_detach_encap to lookup a neigh hash table - * entry in the neigh hash table when a user deletes a rule - */ - e->m_neigh.dev = attr.n->dev; - e->m_neigh.family = attr.n->ops->family; - memcpy(&e->m_neigh.dst_ip, attr.n->primary_key, attr.n->tbl->key_len); + m_neigh.family = attr.n->ops->family; + memcpy(&m_neigh.dst_ip, attr.n->primary_key, attr.n->tbl->key_len); e->out_dev = attr.out_dev; e->route_dev_ifindex = attr.route_dev->ifindex; @@ -423,7 +417,7 @@ int mlx5e_tc_tun_create_header_ipv6(struct mlx5e_priv *priv, * neigh changes it's validity state, we would find the relevant neigh * in the hash. */ - err = mlx5e_rep_encap_entry_attach(netdev_priv(attr.out_dev), e); + err = mlx5e_rep_encap_entry_attach(netdev_priv(attr.out_dev), e, &m_neigh, attr.n->dev); if (err) goto free_encap; diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/tc_tun_encap.c b/drivers/net/ethernet/mellanox/mlx5/core/en/tc_tun_encap.c index 75fcffecfe3db..577216744a176 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en/tc_tun_encap.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/en/tc_tun_encap.c @@ -310,7 +310,7 @@ void mlx5e_tc_update_neigh_used_value(struct mlx5e_neigh_hash_entry *nhe) /* find the relevant neigh according to the cached device and * dst ip pair */ - n = neigh_lookup(tbl, &m_neigh->dst_ip, m_neigh->dev); + n = neigh_lookup(tbl, &m_neigh->dst_ip, READ_ONCE(nhe->neigh_dev)); if (!n) return; diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_rep.h b/drivers/net/ethernet/mellanox/mlx5/core/en_rep.h index 8e04126f088ac..e947921a2d5a3 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en_rep.h +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_rep.h @@ -110,7 +110,6 @@ struct mlx5e_rep_priv *mlx5e_rep_to_rep_priv(struct mlx5_eswitch_rep *rep) } struct mlx5e_neigh { - struct net_device *dev; union { __be32 v4; struct in6_addr v6; @@ -122,6 +121,7 @@ struct mlx5e_neigh_hash_entry { struct rhash_head rhash_node; struct mlx5e_neigh m_neigh; struct mlx5e_priv *priv; + struct net_device *neigh_dev; /* Save the neigh hash entry in a list on the representor in * addition to the hash table. In order to iterate easily over the @@ -175,7 +175,6 @@ struct mlx5e_encap_entry { struct mlx5e_neigh_hash_entry *nhe; /* neigh hash entry list of encaps sharing the same neigh */ struct list_head encap_list; - struct mlx5e_neigh m_neigh; /* a node of the eswitch encap hash table which keeping all the encap * entries */ -- 2.39.5