linux-toradex.git/net/ipv4/ip_input.c, branch v3.10.8

ipv4: set transport header earlier

2013-07-28T23:30:04+00:00

[ Upstream commit 21d1196a35f5686c4323e42a62fdb4b23b0ab4a3 ]

commit 45f00f99d6e ("ipv4: tcp: clean up tcp_v4_early_demux()") added a
performance regression for non GRO traffic, basically disabling
IP early demux.

IPv6 stack resets transport header in ip6_rcv() before calling
IP early demux in ip6_rcv_finish(), while IPv4 does this only in
ip_local_deliver_finish(), _after_ IP early demux.

GRO traffic happened to enable IP early demux because transport header
is also set in inet_gro_receive()

Instead of reverting the faulty commit, we can make IPv4/IPv6 behave the
same : transport_header should be set in ip_rcv() instead of
ip_local_deliver_finish()

ip_local_deliver_finish() can also use skb_network_header_len() which is
faster than ip_hdrlen()

Signed-off-by: Eric Dumazet 
Cc: Neal Cardwell 
Cc: Tom Herbert 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net: Add MIB counters for checksum errors

2013-04-29T19:14:03+00:00

Add MIB counters for checksum errors in IP layer,
and TCP/UDP/ICMP layers, to help diagnose problems.

$ nstat -a | grep  Csum
IcmpInCsumErrors                72                 0.0
TcpInCsumErrors                 382                0.0
UdpInCsumErrors                 463221             0.0
Icmp6InCsumErrors               75                 0.0
Udp6InCsumErrors                173442             0.0
IpExtInCsumErrors               10884              0.0

Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller

ipv[4|6]: correct dropwatch false positive in local_deliver_finish

2013-03-01T20:56:29+00:00

I had a report recently of a user trying to use dropwatch to localise some frame
loss, and they were getting false positives.  Turned out they were using a user
space SCTP stack that used raw sockets to grab frames.  When we don't have a
registered protocol for a given packet, we record it as a drop, even if a raw
socket receieves the frame.  We should only record the drop in the event a raw
socket doesnt exist to receive the frames

Tested by the reported successfully

Signed-off-by: Neil Horman 
Reported-by: William Reich 
Tested-by: William Reich 
CC: "David S. Miller" 
CC: William Reich 
CC: eric.dumazet@gmail.com
Acked-by: Eric Dumazet 
Signed-off-by: David S. Miller

ipv4: Disallow non-namespace aware protocols to register.

2013-02-05T19:42:23+00:00

All in-tree ipv4 protocol implementations are now namespace
aware.  Therefore all the run-time checks are superfluous.

Reject registry of any non-namespace aware ipv4 protocol.
Eventually we'll remove prot->netns_ok and this registry
time check as well.

Signed-off-by: David S. Miller

net: TCP early demux cleanup

2012-07-30T21:53:21+00:00

early_demux() handlers should be called in RCU context, and as we
use skb_dst_set_noref(skb, dst), caller must not exit from RCU context
before dst use (skb_dst(skb)) or release (skb_drop(dst))

Therefore, rcu_read_lock()/rcu_read_unlock() pairs around
->early_demux() are confusing and not needed :

Protocol handlers are already in an RCU read lock section.
(__netif_receive_skb() does the rcu_read_lock() )

Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller

ipv6: Early TCP socket demux

2012-07-26T22:50:39+00:00

This is the IPv6 missing bits for infrastructure added in commit
41063e9dd1195 (ipv4: Early TCP socket demux.)

Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller

ipv4: Fix input route performance regression.

2012-07-26T22:50:39+00:00

With the routing cache removal we lost the "noref" code paths on
input, and this can kill some routing workloads.

Reinstate the noref path when we hit a cached route in the FIB
nexthops.

With help from Eric Dumazet.

Reported-by: Alexander Duyck 
Signed-off-by: David S. Miller 
Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller

tcp: early_demux fixes

2012-07-24T20:54:15+00:00

1) Remove a non needed pskb_may_pull() in tcp_v4_early_demux()
   and fix a potential bug if skb->head was reallocated
   (iph & th pointers were not reloaded)

TCP stack will pull/check headers anyway.

2) must reload iph in ip_rcv_finish() after early_demux()
 call since skb->head might have changed.

3) skb->dev->ifindex can be now replaced by skb->skb_iif

Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller

ipv4: Kill ip_route_input_noref().

2012-07-20T20:30:59+00:00

The "noref" argument to ip_route_input_common() is now always ignored
because we do not cache routes, and in that case we must always grab
a reference to the resulting 'dst'.

Signed-off-by: David S. Miller

ipv4: Kill early demux method return value.

2012-06-28T05:01:22+00:00

It's completely unnecessary.

Signed-off-by: David S. Miller