Re: [PATCH net] mlx4: xdp_prog becomes inactive after ethtool '-L' or '-G'
From: Tariq Toukan <hidden>
Date: 2017-01-30 17:36:33
Hi Martin, Thanks for your patch. It looks good to me, in general. I just have one small comment below. On 28/01/2017 9:40 AM, Martin KaFai Lau wrote:
If the rx-queues ever get re-initialized (e.g. by changing the
number of rx-queues with ethtool -L), the existing xdp_prog becomes
inactive.
The bug is that the xdp_prog ptr has not been carried over from
the old rx-queues to the new rx-queues
Fixes: 47a38e155037 ("net/mlx4_en: add support for fast rx drop bpf program")
Signed-off-by: Martin KaFai Lau <redacted>
---...
quoted hunk ↗ jump to hunk
diff --git a/drivers/net/ethernet/mellanox/mlx4/en_netdev.c b/drivers/net/ethernet/mellanox/mlx4/en_netdev.c index 761f8b12399c..f4179086b3c6 100644 --- a/drivers/net/ethernet/mellanox/mlx4/en_netdev.c +++ b/drivers/net/ethernet/mellanox/mlx4/en_netdev.c@@ -2184,23 +2184,57 @@ static void mlx4_en_update_priv(struct mlx4_en_priv *dst, int mlx4_en_try_alloc_resources(struct mlx4_en_priv *priv, struct mlx4_en_priv *tmp, - struct mlx4_en_port_profile *prof) + struct mlx4_en_port_profile *prof, + bool carry_xdp_prog) { - int t; + struct bpf_prog *xdp_prog = NULL; + int err; + int i; mlx4_en_copy_priv(tmp, priv, prof); + if (carry_xdp_prog) { + /* All rx_rings has the same xdp_prog. Pick the first one */ + xdp_prog = rcu_dereference_protected( + priv->rx_ring[0]->xdp_prog, + lockdep_is_held(&priv->mdev->state_lock)); + + if (xdp_prog) { + xdp_prog = bpf_prog_add(xdp_prog, tmp->rx_ring_num); + if (IS_ERR(xdp_prog)) { + err = PTR_ERR(xdp_prog); + xdp_prog = NULL; + goto err_free; + } + } + }
Why do you prefer dealing with xdp_prog in two stages? You can handle it all at once, after "mlx4_en_alloc_resources()" succeeds.
+
if (mlx4_en_alloc_resources(tmp)) {
en_warn(priv,
"%s: Resource allocation failed, using previous configuration\n",
__func__);
- for (t = 0; t < MLX4_EN_NUM_TX_TYPES; t++) {
- kfree(tmp->tx_ring[t]);
- kfree(tmp->tx_cq[t]);
- }
- return -ENOMEM;
+ err = -ENOMEM;
+ goto err_free;
+ }
+
+ if (xdp_prog) {
+ for (i = 0; i < tmp->rx_ring_num; i++)
+ rcu_assign_pointer(tmp->rx_ring[i]->xdp_prog,
+ xdp_prog);
}
+
return 0;
+
+err_free:
+ if (xdp_prog)
+ bpf_prog_sub(xdp_prog, tmp->rx_ring_num);
+
+ for (i = 0; i < MLX4_EN_NUM_TX_TYPES; i++) {
+ kfree(tmp->tx_ring[i]);
+ kfree(tmp->tx_cq[i]);
+ }
+
+ return err;
}
void mlx4_en_safe_replace_resources(struct mlx4_en_priv *priv,Regards, Tariq Toukan.