diff options
| author | Eric Dumazet <edumazet@google.com> | 2014-06-02 05:26:03 -0700 |
|---|---|---|
| committer | Ben Hutchings <ben@decadent.org.uk> | 2014-09-13 23:41:48 +0100 |
| commit | 64b5c251d5b2cee4a0f697bfb90d79263f6dd517 (patch) | |
| tree | ab041f563f26a1ecb3c3af1ea919560e7f00b3df /include/net/ipip.h | |
| parent | 04619b6ccfe46b096c1cb46fb89e2a0b328a5983 (diff) | |
| download | kernel_samsung_smdk4412-64b5c251d5b2cee4a0f697bfb90d79263f6dd517.zip kernel_samsung_smdk4412-64b5c251d5b2cee4a0f697bfb90d79263f6dd517.tar.gz kernel_samsung_smdk4412-64b5c251d5b2cee4a0f697bfb90d79263f6dd517.tar.bz2 | |
inetpeer: get rid of ip_id_count
[ Upstream commit 73f156a6e8c1074ac6327e0abd1169e95eb66463 ]
Ideally, we would need to generate IP ID using a per destination IP
generator.
linux kernels used inet_peer cache for this purpose, but this had a huge
cost on servers disabling MTU discovery.
1) each inet_peer struct consumes 192 bytes
2) inetpeer cache uses a binary tree of inet_peer structs,
with a nominal size of ~66000 elements under load.
3) lookups in this tree are hitting a lot of cache lines, as tree depth
is about 20.
4) If server deals with many tcp flows, we have a high probability of
not finding the inet_peer, allocating a fresh one, inserting it in
the tree with same initial ip_id_count, (cf secure_ip_id())
5) We garbage collect inet_peer aggressively.
IP ID generation do not have to be 'perfect'
Goal is trying to avoid duplicates in a short period of time,
so that reassembly units have a chance to complete reassembly of
fragments belonging to one message before receiving other fragments
with a recycled ID.
We simply use an array of generators, and a Jenkin hash using the dst IP
as a key.
ipv6_select_ident() is put back into net/ipv6/ip6_output.c where it
belongs (it is only used from this file)
secure_ip_id() and secure_ipv6_id() no longer are needed.
Rename ip_select_ident_more() to ip_select_ident_segs() to avoid
unnecessary decrement/increment of the number of segments.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Diffstat (limited to 'include/net/ipip.h')
| -rw-r--r-- | include/net/ipip.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/include/net/ipip.h b/include/net/ipip.h index 4dccfe3..e8ee3bb 100644 --- a/include/net/ipip.h +++ b/include/net/ipip.h @@ -50,7 +50,7 @@ struct ip_tunnel_prl_entry { int pkt_len = skb->len - skb_transport_offset(skb); \ \ skb->ip_summed = CHECKSUM_NONE; \ - ip_select_ident(skb, &rt->dst, NULL); \ + ip_select_ident(skb, NULL); \ \ err = ip_local_out(skb); \ if (likely(net_xmit_eval(err) == 0)) { \ |