linux-toradex.git/include/net/dst.h, branch v3.7.6

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

2012-08-22T21:21:38+00:00

net: force dst_default_metrics to const section

2012-08-08T23:00:28+00:00

While investigating on network performance problems, I found this little
gem :

$ nm -v vmlinux | grep -1 dst_default_metrics
ffffffff82736540 b busy.46605
ffffffff82736560 B dst_default_metrics
ffffffff82736598 b dst_busy_list

Apparently, declaring a const array without initializer put it in
(writeable) bss section, in middle of possibly often dirtied cache
lines.

Since we really want dst_default_metrics be const to avoid any possible
false sharing and catch any buggy writes, I force a null initializer.

ffffffff818a4c20 R dst_default_metrics

Signed-off-by: Eric Dumazet 
Cc: Ben Hutchings 
Signed-off-by: David S. Miller

net: output path optimizations

2012-08-07T23:24:55+00:00

1) Avoid dirtying neighbour's confirmed field.

  TCP workloads hits this cache line for each incoming ACK.
  Lets write n->confirmed only if there is a jiffie change.

2) Optimize neigh_hh_output() for the common Ethernet case, were
   hh_len is less than 16 bytes. Replace the memcpy() call
   by two inlined 64bit load/stores on x86_64.

Bench results using udpflood test, with -C option (MSG_CONFIRM flag
added to sendto(), to reproduce the n->confirmed dirtying on UDP)

24 threads doing 1.000.000 UDP sendto() on dummy device, 4 runs.

before : 2.247s, 2.235s, 2.247s, 2.318s
after  : 1.884s, 1.905s, 1.891s, 1.895s

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

ipv4: Kill routes during PMTU/redirect updates.

2012-07-20T20:31:22+00:00

Mark them obsolete so there will be a re-lookup to fetch the
FIB nexthop exception info.

Signed-off-by: David S. Miller

net: Document dst->obsolete better.

2012-07-20T20:31:21+00:00

Add a big comment explaining how the field works, and use defines
instead of magic constants for the values assigned to it.

Suggested by Joe Perches.

Signed-off-by: David S. Miller

net: Kill set_dst_metric_rtt().

2012-07-11T05:40:07+00:00

No longer used.

Signed-off-by: David S. Miller

net: Kill dst->_neighbour, accessors, and final uses.

2012-07-05T09:42:00+00:00

No longer used.

Signed-off-by: David S. Miller

net: Add optional SKB arg to dst_ops->neigh_lookup().

2012-07-05T08:04:01+00:00

Causes the handler to use the daddr in the ipv4/ipv6 header when
the route gateway is unspecified (local subnet).

Signed-off-by: David S. Miller

net: Do delayed neigh confirmation.

2012-07-05T08:03:06+00:00

When a dst_confirm() happens, mark the confirmation as pending in the
dst.  Then on the next packet out, when we have the neigh in-hand, do
the update.

This removes the dependency in dst_confirm() of dst's having an
attached neigh.

While we're here, remove the explicit 'dst' NULL check, all except 2
or 3 call sites ensure it's not NULL.  So just fix those cases up.

Signed-off-by: David S. Miller

include/net/dst.h: neaten asterisk placement

2012-06-16T22:20:35+00:00

Fix code style - place the asterisk where it belongs.

Signed-off-by: Eldad Zack 
Signed-off-by: David S. Miller