[PATCH net-next v5 1/3] net/mlx4: Track RX allocation failures in a stat

Joe Damato
2024-05-13T17:29:17Z

mlx4_en_alloc_frags currently returns -ENOMEM when mlx4_alloc_page
fails but does not increment a stat field when this occurs.

A new field called alloc_fail has been added to struct mlx4_en_rx_ring
which is now incremented in mlx4_en_rx_ring when -ENOMEM occurs.

Signed-off-by: Joe Damato <jdamato@fastly.com>
Tested-by: Martin Karsten <mkarsten@uwaterloo.ca>
---
drivers/net/ethernet/mellanox/mlx4/en_netdev.c | 1 +
drivers/net/ethernet/mellanox/mlx4/en_rx.c | 4 +++-
drivers/net/ethernet/mellanox/mlx4/mlx4_en.h | 1 +
3 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/mellanox/mlx4/en_netdev.c b/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
index 4c089cfa027a..4d2f8c458346 100644
--- a/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
@@ -2073,6 +2073,7 @@ static void mlx4_en_clear_stats(struct net_device *dev)
priv->rx_ring[i]->csum_ok = 0;
priv->rx_ring[i]->csum_none = 0;
priv->rx_ring[i]->csum_complete = 0;
+ priv->rx_ring[i]->alloc_fail = 0;
}
}

diff --git a/drivers/net/ethernet/mellanox/mlx4/en_rx.c b/drivers/net/ethernet/mellanox/mlx4/en_rx.c
index 8328df8645d5..15c57e9517e9 100644
--- a/drivers/net/ethernet/mellanox/mlx4/en_rx.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_rx.c
@@ -82,8 +82,10 @@ static int mlx4_en_alloc_frags(struct mlx4_en_priv *priv,

for (i = 0; i < priv->num_frags; i++, frags++) {
if (!frags->page) {
- if (mlx4_alloc_page(priv, frags, gfp))
+ if (mlx4_alloc_page(priv, frags, gfp)) {
+ ring->alloc_fail++;
return -ENOMEM;
+ }
ring->rx_alloc_pages++;
}
rx_desc->data[i].addr = cpu_to_be64(frags->dma +
diff --git a/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h b/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h
index efe3f97b874f..cd70df22724b 100644
--- a/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h
+++ b/drivers/net/ethernet/mellanox/mlx4/mlx4_en.h
@@ -355,6 +355,7 @@ struct mlx4_en_rx_ring {
unsigned long xdp_tx;
unsigned long xdp_tx_full;
unsigned long dropped;
+ unsigned long alloc_fail;
int hwtstamp_rx_filter;
cpumask_var_t affinity_mask;
struct xdp_rxq_info xdp_rxq;
--
2.25.1