net: skb_drop_reason: add document for drop reasons

Add document for following existing drop reasons:

SKB_DROP_REASON_NOT_SPECIFIED
SKB_DROP_REASON_NO_SOCKET
SKB_DROP_REASON_PKT_TOO_SMALL
SKB_DROP_REASON_TCP_CSUM
SKB_DROP_REASON_SOCKET_FILTER
SKB_DROP_REASON_UDP_CSUM

Signed-off-by: Menglong Dong <imagedong@tencent.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index a27bcc4f7e9a92ea4f4f4f6e5f454bb4f8099f66..f04e3a1f4455d914e93a9425157f8b052b59464a 100644 (file)
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -314,12 +314,12 @@ struct sk_buff;
  * used to translate the reason to string.
  */
 enum skb_drop_reason {
-       SKB_DROP_REASON_NOT_SPECIFIED,
-       SKB_DROP_REASON_NO_SOCKET,
-       SKB_DROP_REASON_PKT_TOO_SMALL,
-       SKB_DROP_REASON_TCP_CSUM,
-       SKB_DROP_REASON_SOCKET_FILTER,
-       SKB_DROP_REASON_UDP_CSUM,
+       SKB_DROP_REASON_NOT_SPECIFIED,  /* drop reason is not specified */
+       SKB_DROP_REASON_NO_SOCKET,      /* socket not found */
+       SKB_DROP_REASON_PKT_TOO_SMALL,  /* packet size is too small */
+       SKB_DROP_REASON_TCP_CSUM,       /* TCP checksum error */
+       SKB_DROP_REASON_SOCKET_FILTER,  /* dropped by socket filter */
+       SKB_DROP_REASON_UDP_CSUM,       /* UDP checksum error */
        SKB_DROP_REASON_MAX,
 };