udp: add tracepoints for queueing skb to rcvbuf
This patch adds a tracepoint to __udp_queue_rcv_skb to get the
return value of ip_queue_rcv_skb. It indicates why kernel drops
a packet at this point.
ip_queue_rcv_skb returns following values in the packet drop case:
rcvbuf is full : -ENOMEM
sk_filter returns error : -EINVAL, -EACCESS, -ENOMEM, etc.
__sk_mem_schedule returns error: -ENOBUF
Signed-off-by: Satoru Moriya <satoru.moriya@hds.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/core/net-traces.c b/net/core/net-traces.c
index 7f1bb2a..13aab64 100644
--- a/net/core/net-traces.c
+++ b/net/core/net-traces.c
@@ -28,6 +28,7 @@
#include <trace/events/skb.h>
#include <trace/events/net.h>
#include <trace/events/napi.h>
+#include <trace/events/udp.h>
EXPORT_TRACEPOINT_SYMBOL_GPL(kfree_skb);