This is a note to let you know that I've just added the patch titled
mlx4: Invoke softirqs after napi_reschedule
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
mlx4-invoke-softirqs-after-napi_reschedule.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From foo@baz Tue Feb 14 16:29:59 PST 2017
From: Benjamin Poirier <bpoirier@xxxxxxxx>
Date: Mon, 6 Feb 2017 10:14:31 -0800
Subject: mlx4: Invoke softirqs after napi_reschedule
From: Benjamin Poirier <bpoirier@xxxxxxxx>
[ Upstream commit bd4ce941c8d5b862b2f83364be5dbe8fc8ab48f8 ]
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@xxxxxxxxx>
Signed-off-by: Benjamin Poirier <bpoirier@xxxxxxxx>
Acked-by: Eric Dumazet <edumazet@xxxxxxxxxx>
Reviewed-by: Tariq Toukan <tariqt@xxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/ethernet/mellanox/mlx4/en_rx.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
--- a/drivers/net/ethernet/mellanox/mlx4/en_rx.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_rx.c
@@ -502,8 +502,11 @@ void mlx4_en_recover_from_oom(struct mlx
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();
+ }
}
}
Patches currently in stable-queue which might be from bpoirier@xxxxxxxx are
queue-4.4/mlx4-invoke-softirqs-after-napi_reschedule.patch