[PATCH v3 net-next 0/7] net: use kfree_skb_reason() for ip/udp packet receive

[menglong8.dong@gmail.com]

From: Menglong Dong <imagedong@tencent.com>

In this series patches, kfree_skb() is replaced with kfree_skb_reason()
during ipv4 and udp4 packet receiving path, and following drop reasons
are introduced:

SKB_DROP_REASON_SOCKET_FILTER
SKB_DROP_REASON_NETFILTER_DROP
SKB_DROP_REASON_OTHERHOST
SKB_DROP_REASON_IP_CSUM
SKB_DROP_REASON_IP_INHDR
SKB_DROP_REASON_IP_RPFILTER
SKB_DROP_REASON_UNICAST_IN_L2_MULTICAST
SKB_DROP_REASON_XFRM_POLICY
SKB_DROP_REASON_IP_NOPROTO
SKB_DROP_REASON_SOCKET_RCVBUFF
SKB_DROP_REASON_PROTO_MEM

TCP is more complex, so I left it in the next series.

I just figure out how __print_symbolic() works. It doesn't base on the
array index, but searching for symbols by loop. So I'm a little afraid
it's performance.

Changes since v2:
- use SKB_DROP_REASON_PKT_TOO_SMALL for a path in ip_rcv_core()

Changes since v1:
- add document for all drop reasons, as David advised
- remove unreleated cleanup
- remove EARLY_DEMUX and IP_ROUTE_INPUT drop reason
- replace {UDP, TCP}_FILTER with SOCKET_FILTER


Menglong Dong (7):
  net: skb_drop_reason: add document for drop reasons
  net: netfilter: use kfree_drop_reason() for NF_DROP
  net: ipv4: use kfree_skb_reason() in ip_rcv_core()
  net: ipv4: use kfree_skb_reason() in ip_rcv_finish_core()
  net: ipv4: use kfree_skb_reason() in ip_protocol_deliver_rcu()
  net: udp: use kfree_skb_reason() in udp_queue_rcv_one_skb()
  net: udp: use kfree_skb_reason() in __udp_queue_rcv_skb()

 include/linux/skbuff.h     | 38 ++++++++++++++++++++++++++++++++------
 include/trace/events/skb.h | 11 +++++++++++
 net/ipv4/ip_input.c        | 31 +++++++++++++++++++++++--------
 net/ipv4/udp.c             | 22 ++++++++++++++++------
 net/netfilter/core.c       |  3 ++-
 5 files changed, 84 insertions(+), 21 deletions(-)

-- 
2.27.0