From: Vlad Buslov <vladbu@mellanox.com>
Date: Wed, 13 Mar 2019 19:50:24 +0200
Subject: net/mlx5e: Protect unready flows with dedicated lock
Patch-mainline: v5.4-rc1
Git-commit: ad86755b18d5edf1956f6d25c844f27289216877
References: jsc#SLE-8464
In order to remove dependency on rtnl lock for protecting unready_flows
list when reoffloading unready flows on workqueue, extend representor
uplink private structure with dedicated 'unready_flows_lock' mutex. Take
the lock in all users of unready_flows list before accessing it. Implement
helper functions to add and delete unready flow.
Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Reviewed-by: Jianbo Liu <jianbol@mellanox.com>
Reviewed-by: Roi Dayan <roid@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
drivers/net/ethernet/mellanox/mlx5/core/en_rep.c | 2 +
drivers/net/ethernet/mellanox/mlx5/core/en_rep.h | 2 +
drivers/net/ethernet/mellanox/mlx5/core/en_tc.c | 43 +++++++++++++++++++----
3 files changed, 40 insertions(+), 7 deletions(-)
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_rep.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_rep.c
@@ -1560,6 +1560,7 @@ static int mlx5e_init_rep_tx(struct mlx5
if (rpriv->rep->vport == MLX5_VPORT_UPLINK) {
uplink_priv = &rpriv->uplink_priv;
+ mutex_init(&uplink_priv->unready_flows_lock);
INIT_LIST_HEAD(&uplink_priv->unready_flows);
/* init shared tc flow table */
@@ -1604,6 +1605,7 @@ static void mlx5e_cleanup_rep_tx(struct
/* delete shared tc flow table */
mlx5e_tc_esw_cleanup(&rpriv->uplink_priv.tc_ht);
+ mutex_destroy(&rpriv->uplink_priv.unready_flows_lock);
}
}
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_rep.h
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_rep.h
@@ -75,6 +75,8 @@ struct mlx5_rep_uplink_priv {
struct mlx5_tun_entropy tun_entropy;
+ /* protects unready_flows */
+ struct mutex unready_flows_lock;
struct list_head unready_flows;
struct work_struct reoffload_flows_work;
};
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_tc.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_tc.c
@@ -996,6 +996,25 @@ mlx5e_tc_unoffload_from_slow_path(struct
flow_flag_clear(flow, SLOW);
}
+/* Caller must obtain uplink_priv->unready_flows_lock mutex before calling this
+ * function.
+ */
+static void unready_flow_add(struct mlx5e_tc_flow *flow,
+ struct list_head *unready_flows)
+{
+ flow_flag_set(flow, NOT_READY);
+ list_add_tail(&flow->unready, unready_flows);
+}
+
+/* Caller must obtain uplink_priv->unready_flows_lock mutex before calling this
+ * function.
+ */
+static void unready_flow_del(struct mlx5e_tc_flow *flow)
+{
+ list_del(&flow->unready);
+ flow_flag_clear(flow, NOT_READY);
+}
+
static void add_unready_flow(struct mlx5e_tc_flow *flow)
{
struct mlx5_rep_uplink_priv *uplink_priv;
@@ -1006,14 +1025,24 @@ static void add_unready_flow(struct mlx5
rpriv = mlx5_eswitch_get_uplink_priv(esw, REP_ETH);
uplink_priv = &rpriv->uplink_priv;
- flow_flag_set(flow, NOT_READY);
- list_add_tail(&flow->unready, &uplink_priv->unready_flows);
+ mutex_lock(&uplink_priv->unready_flows_lock);
+ unready_flow_add(flow, &uplink_priv->unready_flows);
+ mutex_unlock(&uplink_priv->unready_flows_lock);
}
static void remove_unready_flow(struct mlx5e_tc_flow *flow)
{
- list_del(&flow->unready);
- flow_flag_clear(flow, NOT_READY);
+ struct mlx5_rep_uplink_priv *uplink_priv;
+ struct mlx5e_rep_priv *rpriv;
+ struct mlx5_eswitch *esw;
+
+ esw = flow->priv->mdev->priv.eswitch;
+ rpriv = mlx5_eswitch_get_uplink_priv(esw, REP_ETH);
+ uplink_priv = &rpriv->uplink_priv;
+
+ mutex_lock(&uplink_priv->unready_flows_lock);
+ unready_flow_del(flow);
+ mutex_unlock(&uplink_priv->unready_flows_lock);
}
static int
@@ -3732,10 +3761,10 @@ void mlx5e_tc_reoffload_flows_work(struc
reoffload_flows_work);
struct mlx5e_tc_flow *flow, *tmp;
- rtnl_lock();
+ mutex_lock(&rpriv->unready_flows_lock);
list_for_each_entry_safe(flow, tmp, &rpriv->unready_flows, unready) {
if (!mlx5e_tc_add_fdb_flow(flow->priv, flow, NULL))
- remove_unready_flow(flow);
+ unready_flow_del(flow);
}
- rtnl_unlock();
+ mutex_unlock(&rpriv->unready_flows_lock);
}