ip: use rb trees for IP frag queue.
authorPeter Oskolkov <posk@google.com>
Thu, 2 Aug 2018 23:34:39 +0000 (23:34 +0000)
committerDavid S. Miller <davem@davemloft.net>
Mon, 6 Aug 2018 00:16:46 +0000 (17:16 -0700)
commitfa0f527358bd900ef92f925878ed6bfbd51305cc
tree4ecb0bb64c8baa58162b3f03046c0643a140ece0
parent385114dec8a49b5e5945e77ba7de6356106713f4
ip: use rb trees for IP frag queue.

Similar to TCP OOO RX queue, it makes sense to use rb trees to store
IP fragments, so that OOO fragments are inserted faster.

Tested:

- a follow-up patch contains a rather comprehensive ip defrag
  self-test (functional)
- ran neper `udp_stream -c -H <host> -F 100 -l 300 -T 20`:
    netstat --statistics
    Ip:
        282078937 total packets received
        0 forwarded
        0 incoming packets discarded
        946760 incoming packets delivered
        18743456 requests sent out
        101 fragments dropped after timeout
        282077129 reassemblies required
        944952 packets reassembled ok
        262734239 packet reassembles failed
   (The numbers/stats above are somewhat better re:
    reassemblies vs a kernel without this patchset. More
    comprehensive performance testing TBD).

Reported-by: Jann Horn <jannh@google.com>
Reported-by: Juha-Matti Tilli <juha-matti.tilli@iki.fi>
Suggested-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Peter Oskolkov <posk@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
include/linux/skbuff.h
include/net/inet_frag.h
net/ipv4/inet_fragment.c
net/ipv4/ip_fragment.c
net/ipv6/netfilter/nf_conntrack_reasm.c
net/ipv6/reassembly.c