mlx4 uses a private struct net_device_stats in a vain attempt
to avoid races.
This is buggy because multiple cpus could call mlx4_en_get_stats()
at the same time, so ret_stats can not guarantee stable results.
To fix this, we need to switch to ndo_get_stats64() as this
method provides per-thread storage.
This allows to reduce mlx4_en_priv bloat.
Signed-off-by: Eric Dumazet <eduma...@google.com>
Cc: Willem de Bruijn <will...@google.com>
Cc: Eugenia Emantayev <euge...@mellanox.com>
---
drivers/net/ethernet/mellanox/mlx4/en_netdev.c | 11 ++++++-----
drivers/net/ethernet/mellanox/mlx4/mlx4_en.h | 1 -
2 files changed, 6 insertions(+), 6 deletions(-)
diff --git a/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
b/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
index bd637c4eff13..a4fc6e966505 100644
--- a/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
@@ -1296,15 +1296,16 @@ static void mlx4_en_tx_timeout(struct net_device *dev)
}
-static struct net_device_stats *mlx4_en_get_stats(struct net_device *dev)
+static struct rtnl_link_stats64 *
+mlx4_en_get_stats64(struct net_device *dev, struct rtnl_link_stats64 *stats)
{
struct mlx4_en_priv *priv = netdev_priv(dev);
spin_lock_bh(&priv->stats_lock);
- memcpy(&priv->ret_stats, &priv->stats, sizeof(priv->stats));
+ netdev_stats_to_stats64(stats, &priv->stats);
spin_unlock_bh(&priv->stats_lock);
- return &priv->ret_stats;
+ return stats;
}
static void mlx4_en_set_default_moderation(struct mlx4_en_priv *priv)
@@ -2487,7 +2488,7 @@ static const struct net_device_ops mlx4_netdev_ops = {
.ndo_stop = mlx4_en_close,
.ndo_start_xmit = mlx4_en_xmit,
.ndo_select_queue = mlx4_en_select_queue,
- .ndo_get_stats = mlx4_en_get_stats,
+ .ndo_get_stats64 = mlx4_en_get_stats64,
.ndo_set_rx_mode = mlx4_en_set_rx_mode,
.ndo_set_mac_address = mlx4_en_set_mac,
.ndo_validate_addr = eth_validate_addr,
@@ -2519,7 +2520,7 @@ static const struct net_device_ops mlx4_netdev_ops_master
= {
.ndo_stop = mlx4_en_close,
.ndo_start_xmit = mlx4_en_xmit,
.ndo_select_queue = mlx4_en_select_queue,
- .ndo_get_stats = mlx4_en_get_stats,
+ .ndo_get_stats64 = mlx4_en_get_stats64,
.ndo_set_rx_mode = mlx4_en_set_rx_mode,
.ndo_set_mac_address = mlx4_en_set_mac,
.ndo_validate_addr = eth_validate_addr,
diff --git a/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h
b/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h
index 9a9124031fc7..bfda84df8aae 100644
--- a/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h
+++ b/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h
@@ -484,7 +484,6 @@ struct mlx4_en_priv {
struct net_device *dev;
unsigned long active_vlans[BITS_TO_LONGS(VLAN_N_VID)];
struct net_device_stats stats;
- struct net_device_stats ret_stats;
struct mlx4_en_port_state port_state;
spinlock_t stats_lock;
struct ethtool_flow_id ethtool_rules[MAX_NUM_OF_FS_RULES];
--
2.8.0.rc3.226.g39d4020
