xdp/trace: extend tracepoint in devmap with an err

Extending tracepoint xdp:xdp_devmap_xmit in devmap with an err code
allow people to easier identify the reason behind the ndo_xdp_xmit
call to a given driver is failing.

Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

1 files changed, 3 insertions, 2 deletions

diff --git a/kernel/bpf/devmap.c b/kernel/bpf/devmap.c
index 77908311ec98..ae16d0c373ef 100644
--- a/kernel/bpf/devmap.c
+++ b/kernel/bpf/devmap.c
@@ -220,7 +220,7 @@ static int bq_xmit_all(struct bpf_dtab_netdev *obj,
                          struct xdp_bulk_queue *bq)
 {
         struct net_device *dev = obj->dev;
-        int sent = 0, drops = 0;
+        int sent = 0, drops = 0, err = 0;
         int i;
 
         if (unlikely(!bq->count))
@@ -234,6 +234,7 @@ static int bq_xmit_all(struct bpf_dtab_netdev *obj,
 
         sent = dev->netdev_ops->ndo_xdp_xmit(dev, bq->count, bq->q);
         if (sent < 0) {
+                err = sent;
                 sent = 0;
                 goto error;
         }
@@ -242,7 +243,7 @@ out:
         bq->count = 0;
 
         trace_xdp_devmap_xmit(&obj->dtab->map, obj->bit,
-                              sent, drops, bq->dev_rx, dev);
+                              sent, drops, bq->dev_rx, dev, err);
         bq->dev_rx = NULL;
         return 0;
 error: