mlx4: Invoke softirqs after napi_reschedule

mlx4 may schedule napi from a workqueue. Afterwards, softirqs are not run
in a deterministic time frame and the following message may be logged:
NOHZ: local_softirq_pending 08

The problem is the same as what was described in commit ec13ee80145c
("virtio_net: invoke softirqs after __napi_schedule") and this patch
applies the same fix to mlx4.

Fixes: 07841f9d94c1 ("net/mlx4_en: Schedule napi when RX buffers allocation fails")
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Benjamin Poirier <bpoirier@suse.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/mellanox/mlx4/en_rx.c b/drivers/net/ethernet/mellanox/mlx4/en_rx.c
index eac527e25ec902c2a586e9952272b9e8e599e2c8..cc003fdf0ed929a981b1403f6a7d0099825fec4b 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlx4/en_rx.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_rx.c
@@ -514,8 +514,11 @@ void mlx4_en_recover_from_oom(struct mlx4_en_priv *priv)
                return;
 
        for (ring = 0; ring < priv->rx_ring_num; ring++) {
-               if (mlx4_en_is_ring_empty(priv->rx_ring[ring]))
+               if (mlx4_en_is_ring_empty(priv->rx_ring[ring])) {
+                       local_bh_disable();
                        napi_reschedule(&priv->rx_cq[ring]->napi);
+                       local_bh_enable();
+               }
        }
 }