linux.git/net/ipv4, branch v2.6.30

tcp: tcp_vegas ssthresh bugfix

2009-05-26T05:44:59+00:00

This patch fixes ssthresh accounting issues in tcp_vegas when cwnd decreases

Signed-off-by: Doug Leith 
Signed-off-by: David S. Miller

ipv4: Fix oops with FIB_TRIE

2009-05-21T22:20:59+00:00

It seems we can fix this by disabling preemption while we re-balance the 
trie. This is with the CONFIG_CLASSIC_RCU. It's been stress-tested at high 
loads continuesly taking a full BGP table up/down via iproute -batch.

Note. fib_trie is not updated for CONFIG_PREEMPT_RCU

Reported-by: Andrei Popa
Signed-off-by: Robert Olsson 
Signed-off-by: David S. Miller

net: fix rtable leak in net/ipv4/route.c

2009-05-21T00:18:02+00:00

Alexander V. Lukyanov found a regression in 2.6.29 and made a complete
analysis found in http://bugzilla.kernel.org/show_bug.cgi?id=13339
Quoted here because its a perfect one :

begin_of_quotation
 2.6.29 patch has introduced flexible route cache rebuilding. Unfortunately the
 patch has at least one critical flaw, and another problem.

 rt_intern_hash calculates rthi pointer, which is later used for new entry
 insertion. The same loop calculates cand pointer which is used to clean the
 list. If the pointers are the same, rtable leak occurs, as first the cand is
 removed then the new entry is appended to it.

 This leak leads to unregister_netdevice problem (usage count > 0).

 Another problem of the patch is that it tries to insert the entries in certain
 order, to facilitate counting of entries distinct by all but QoS parameters.
 Unfortunately, referencing an existing rtable entry moves it to list beginning,
 to speed up further lookups, so the carefully built order is destroyed.

 For the first problem the simplest patch it to set rthi=0 when rthi==cand, but
 it will also destroy the ordering.
end_of_quotation

Problematic commit is 1080d709fb9d8cd4392f93476ee46a9d6ea05a5b
(net: implement emergency route cache rebulds when gc_elasticity is exceeded)

Trying to keep dst_entries ordered is too complex and breaks the fact that
order should depend on the frequency of use for garbage collection.

A possible fix is to make rt_intern_hash() simpler, and only makes
rt_check_expire() a litle bit smarter, being able to cope with an arbitrary
entries order. The added loop is running on cache hot data, while cpu
is prefetching next object, so should be unnoticied.

Reported-and-analyzed-by: Alexander V. Lukyanov 
Signed-off-by: Eric Dumazet 
Acked-by: Neil Horman 
Signed-off-by: David S. Miller

net: fix length computation in rt_check_expire()

2009-05-21T00:18:01+00:00

rt_check_expire() computes average and standard deviation of chain lengths,
but not correclty reset length to 0 at beginning of each chain.
This probably gives overflows for sum2 (and sum) on loaded machines instead
of meaningful results.

Signed-off-by: Eric Dumazet 
Acked-by: Neil Horman 
Signed-off-by: David S. Miller

ipv4: make default for INET_LRO consistent with help text

2009-05-19T04:48:38+00:00

Commit e81963b1 ("ipv4: Make INET_LRO a bool instead of tristate.")
changed this config from tristate to bool.  Add default so that it is
consistent with the help text.

Signed-off-by: Frans Pop 
Signed-off-by: David S. Miller

tcp: fix MSG_PEEK race check

2009-05-18T22:05:40+00:00

Commit 518a09ef11 (tcp: Fix recvmsg MSG_PEEK influence of
blocking behavior) lets the loop run longer than the race check
did previously expect, so we need to be more careful with this
check and consider the work we have been doing.

I tried my best to deal with urg hole madness too which happens
here:
	if (!sock_flag(sk, SOCK_URGINLINE)) {
		++*seq;
		...
by using additional offset by one but I certainly have very
little interest in testing that part.

Signed-off-by: Ilpo Järvinen 
Tested-by: Frans Pop 
Tested-by: Ian Zimmermann 
Signed-off-by: David S. Miller

ipconfig: handle case of delayed DHCP server

2009-05-18T03:39:33+00:00

If a DHCP server is delayed, it's possible for the client to receive the 
DHCPOFFER after it has already sent out a new DHCPDISCOVER message from 
a second interface.  The client then sends out a DHCPREQUEST from the 
second interface, but the server doesn't recognize the device and 
rejects the request.

This patch simply tracks the current device being configured and throws 
away the OFFER if it is not intended for the current device.  A more 
sophisticated approach would be to put the OFFER information into the 
struct ic_device rather than storing it globally.

Signed-off-by: Chris Friesen 
Signed-off-by: David S. Miller

ipv4: Make INET_LRO a bool instead of tristate.

2009-05-08T19:45:26+00:00

This code is used as a library by several device drivers,
which select INET_LRO.

If some are modules and some are statically built into the
kernel, we get build failures if INET_LRO is modular.

Signed-off-by: David S. Miller

tcp: Fix tcp_prequeue() to get correct rto_min value

2009-05-04T18:11:01+00:00

tcp_prequeue() refers to the constant value (TCP_RTO_MIN) regardless of
the actual value might be tuned. The following patches fix this and make
tcp_prequeue get the actual value returns from tcp_rto_min().

Signed-off-by: Satoru SATOH 
Signed-off-by: David S. Miller

netfilter: revised locking for x_tables

2009-04-29T05:36:33+00:00

The x_tables are organized with a table structure and a per-cpu copies
of the counters and rules. On older kernels there was a reader/writer 
lock per table which was a performance bottleneck. In 2.6.30-rc, this
was converted to use RCU and the counters/rules which solved the performance
problems for do_table but made replacing rules much slower because of
the necessary RCU grace period.

This version uses a per-cpu set of spinlocks and counters to allow to
table processing to proceed without the cache thrashing of a global
reader lock and keeps the same performance for table updates.

Signed-off-by: Stephen Hemminger 
Acked-by: Linus Torvalds 
Signed-off-by: David S. Miller