Commit Graph

3061 Commits

Author SHA1 Message Date
Eric Dumazet
ea781f197d netfilter: nf_conntrack: use SLAB_DESTROY_BY_RCU and get rid of call_rcu()
Use "hlist_nulls" infrastructure we added in 2.6.29 for RCUification of UDP & TCP.

This permits an easy conversion from call_rcu() based hash lists to a
SLAB_DESTROY_BY_RCU one.

Avoiding call_rcu() delay at nf_conn freeing time has numerous gains.

First, it doesnt fill RCU queues (up to 10000 elements per cpu).
This reduces OOM possibility, if queued elements are not taken into account
This reduces latency problems when RCU queue size hits hilimit and triggers
emergency mode.

- It allows fast reuse of just freed elements, permitting better use of
CPU cache.

- We delete rcu_head from "struct nf_conn", shrinking size of this structure
by 8 or 16 bytes.

This patch only takes care of "struct nf_conn".
call_rcu() is still used for less critical conntrack parts, that may
be converted later if necessary.

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
2009-03-25 21:05:46 +01:00
Patrick McHardy
1f9352ae22 netfilter: {ip,ip6,arp}_tables: fix incorrect loop detection
Commit e1b4b9f ([NETFILTER]: {ip,ip6,arp}_tables: fix exponential worst-case
search for loops) introduced a regression in the loop detection algorithm,
causing sporadic incorrectly detected loops.

When a chain has already been visited during the check, it is treated as
having a standard target containing a RETURN verdict directly at the
beginning in order to not check it again. The real target of the first
rule is then incorrectly treated as STANDARD target and checked not to
contain invalid verdicts.

Fix by making sure the rule does actually contain a standard target.

Based on patch by Francis Dupont <Francis_Dupont@isc.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
2009-03-25 19:26:35 +01:00
Eric Dumazet
b8dfe49877 netfilter: factorize ifname_compare()
We use same not trivial helper function in four places. We can factorize it.

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
2009-03-25 17:31:52 +01:00
Scott James Remnant
95ba434f89 netfilter: auto-load ip_queue module when socket opened
The ip_queue module is missing the net-pf-16-proto-3 alias that would
causae it to be auto-loaded when a socket of that type is opened.  This
patch adds the alias.

Signed-off-by: Scott James Remnant <scott@canonical.com>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
2009-03-16 15:31:10 +01:00
Pablo Neira Ayuso
1db7a748df netfilter: conntrack: increase drop stats if sequence adjustment fails
This patch increases the statistics of packets drop if the sequence
adjustment fails in ipv4_confirm().

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
2009-03-16 15:18:50 +01:00
Stephen Hemminger
67c0d57930 netfilter: Kconfig spelling fixes (trivial)
Signed-off-by: Stephen Hemminger <sheminger@vyatta.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
2009-03-16 15:17:23 +01:00
Eric Leblond
ca735b3aaa netfilter: use a linked list of loggers
This patch modifies nf_log to use a linked list of loggers for each
protocol. This list of loggers is read and write protected with a
mutex.

This patch separates registration and binding. To be used as
logging module, a module has to register calling nf_log_register()
and to bind to a protocol it has to call nf_log_bind_pf().
This patch also converts the logging modules to the new API. For nfnetlink_log,
it simply switchs call to register functions to call to bind function and
adds a call to nf_log_register() during init. For other modules, it just
remove a const flag from the logger structure and replace it with a
__read_mostly.

Signed-off-by: Eric Leblond <eric@inl.fr>
Signed-off-by: Patrick McHardy <kaber@trash.net>
2009-03-16 14:54:21 +01:00
Eric Dumazet
08361aa807 netfilter: ip_tables: unfold two critical loops in ip_packet_match()
While doing oprofile tests I noticed two loops are not properly unrolled by gcc

Using a hand coded unrolled loop provides nice speedup : ipt_do_table
credited of 2.52 % of cpu instead of 3.29 % in tbench.

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
2009-02-20 11:03:33 +01:00
Stephen Hemminger
784544739a netfilter: iptables: lock free counters
The reader/writer lock in ip_tables is acquired in the critical path of
processing packets and is one of the reasons just loading iptables can cause
a 20% performance loss. The rwlock serves two functions:

1) it prevents changes to table state (xt_replace) while table is in use.
   This is now handled by doing rcu on the xt_table. When table is
   replaced, the new table(s) are put in and the old one table(s) are freed
   after RCU period.

2) it provides synchronization when accesing the counter values.
   This is now handled by swapping in new table_info entries for each cpu
   then summing the old values, and putting the result back onto one
   cpu.  On a busy system it may cause sampling to occur at different
   times on each cpu, but no packet/byte counts are lost in the process.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>

Sucessfully tested on my dual quad core machine too, but iptables only (no ipv6 here)
BTW, my new "tbench 8" result is 2450 MB/s, (it was 2150 MB/s not so long ago)

Acked-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
2009-02-20 10:35:32 +01:00
Jan Engelhardt
4323362e49 netfilter: xtables: add backward-compat options
Concern has been expressed about the changing Kconfig options.
Provide the old options that forward-select.

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
2009-02-19 11:16:03 +01:00
Jan Engelhardt
cfac5ef7b9 netfilter: Combine ipt_ttl and ip6t_hl source
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
2009-02-18 18:39:31 +01:00
Jan Engelhardt
563d36eb3f netfilter: Combine ipt_TTL and ip6t_HL source
Suggested by: James King <t.james.king@gmail.com>

Similarly to commit c9fd496809, merge
TTL and HL. Since HL does not depend on any IPv6-specific function,
no new module dependencies would arise.

With slight adjustments to the Kconfig help text.

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
2009-02-18 18:38:40 +01:00
Eric Dumazet
ddc214c43a netfilter: arp_tables: unfold two critical loops in arp_packet_match()
x86 and powerpc can perform long word accesses in an efficient maner.
We can use this to unroll two loops in arp_packet_match(), to
perform arithmetic on long words instead of bytes. This is a win
on x86_64 for example.

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
2009-02-18 17:47:50 +01:00
Stephen Hemminger
9c8222b9e7 netfilter: x_tables: remove unneeded initializations
Later patches change the locking on xt_table and the initialization of
the lock element is not needed since the lock is always initialized in
xt_table_register anyway.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
2009-02-18 16:30:20 +01:00
Thomas Gleixner
1c10c49d83 net: replace commatas with semicolons
Impact: syntax fix

Interestingly enough this compiles w/o any complaints:

	orphans = percpu_counter_sum_positive(&tcp_orphan_count),
	sockets = percpu_counter_sum_positive(&tcp_sockets_allocated),

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-02-16 00:08:56 -08:00
Patrick Ohly
51f31cabe3 ip: support for TX timestamps on UDP and RAW sockets
Instructions for time stamping outgoing packets are take from the
socket layer and later copied into the new skb.

Signed-off-by: Patrick Ohly <patrick.ohly@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-02-15 22:43:38 -08:00
Herbert Xu
aa6320d336 gro: Optimise TCP packet reception
gro: Optimise TCP packet reception

As this function can be called more than half a million times for
10GbE, it's important to optimise it as much as we can.

This patch uses bit ops to logical ops, as well as open coding
memcmp to exploit alignment properties.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-02-08 20:22:19 -08:00
Herbert Xu
a5ad24be72 gro: Optimise IPv4 packet reception
As this function can be called more than half a million times for
10GbE, it's important to optimise it as much as we can.

This patch does some obvious changes to use 2-byte and 4-byte
operations instead of byte-oriented ones where possible.  Bit
ops are also used to replace logical ops to reduce branching.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-02-08 20:22:19 -08:00
David S. Miller
409f0a9014 Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
Conflicts:
	drivers/net/wireless/iwlwifi/iwl-agn.c
	drivers/net/wireless/iwlwifi/iwl3945-base.c
2009-02-07 02:52:44 -08:00
Ilpo Järvinen
69ebbf58f3 ipmr: use goto to common label instead of opencoding
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-02-06 23:46:51 -08:00
Jesper Dangaard Brouer
2783ef2312 udp: Fix potential wrong ip_hdr(skb) pointers
Like the UDP header fix, pskb_may_pull() can potentially
alter the SKB buffer.  Thus the saddr and daddr, pointers
may point to the old skb->data buffer.

I haven't seen corruptions, as its only seen if the old
skb->data buffer were reallocated by another user and
written into very quickly (or poison'd by SLAB debugging).

Signed-off-by: Jesper Dangaard Brouer <hawk@comx.dk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-02-06 01:59:12 -08:00
David S. Miller
a23f4bbd8d Revert "tcp: Always set urgent pointer if it's beyond snd_nxt"
This reverts commit 64ff3b938e.

Jeff Chua reports that it breaks rlogin for him.

Signed-off-by: David S. Miller <davem@davemloft.net>
2009-02-05 15:38:31 -08:00
Jesper Dangaard Brouer
7b5e56f9d6 udp: Fix UDP short packet false positive
The UDP header pointer assignment must happen after calling
pskb_may_pull().  As pskb_may_pull() can potentially alter the SKB
buffer.

This was exposted by running multicast traffic through the NIU driver,
as it won't prepull the protocol headers into the linear area on
receive.

Signed-off-by: Jesper Dangaard Brouer <hawk@comx.dk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-02-05 15:05:45 -08:00
David S. Miller
b3ff29d2cc Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
Conflicts:
	drivers/net/Kconfig
2009-02-03 00:15:35 -08:00
Eric Dumazet
e408b8dcb5 udp: increments sk_drops in __udp_queue_rcv_skb()
Commit 93821778de (udp: Fix rcv socket
locking) accidentally removed sk_drops increments for UDP IPV4
sockets.

This field can be used to detect incorrect sizing of socket receive
buffers.

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-02-02 13:41:57 -08:00
Herbert Xu
f15fbcd7d8 ipv4: Delete redundant sk_family assignment
sk_alloc now sets sk_family so this is redundant.  In fact it caught
my eye because sock_init_data already uses sk_family so this is too
late anyway.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-02-01 22:24:43 -08:00
Eric Dumazet
24dd1fa184 net: move bsockets outside of read only beginning of struct inet_hashinfo
And switch bsockets to atomic_t since it might be changed in parallel.

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-02-01 12:31:33 -08:00
Stephen Hemminger
5add300975 inet: Fix virt-manager regression due to bind(0) changes.
From: Stephen Hemminger <shemminger@vyatta.com>

Fix regression introduced by a9d8f9110d
("inet: Allowing more than 64k connections and heavily optimize
bind(0) time.")

Based upon initial patches and feedback from Evegniy Polyakov and
Eric Dumazet.

From Eric Dumazet:
--------------------
Also there might be a problem at line 175

if (sk->sk_reuse && sk->sk_state != TCP_LISTEN && --attempts >= 0) { 
	spin_unlock(&head->lock);
	goto again;

If we entered inet_csk_get_port() with a non null snum, we can "goto again"
while it was not expected.
--------------------

Signed-off-by: David S. Miller <davem@davemloft.net>
2009-02-01 01:40:17 -08:00
Stephen Hemminger
eefef1cf76 net: add ARP notify option for devices
This adds another inet device option to enable gratuitous ARP
when device is brought up or address change. This is handy for
clusters or virtualization.

Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-02-01 01:04:33 -08:00
Harvey Harrison
09640e6365 net: replace uses of __constant_{endian}
Base versions handle constant folding now.

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-02-01 00:45:17 -08:00
David S. Miller
05bee47377 Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
Conflicts:
	drivers/net/e1000/e1000_main.c
2009-01-30 14:31:07 -08:00
Herbert Xu
86911732d3 gro: Avoid copying headers of unmerged packets
Unfortunately simplicity isn't always the best.  The fraginfo
interface turned out to be suboptimal.  The problem was quite
obvious.  For every packet, we have to copy the headers from
the frags structure into skb->head, even though for 99% of the
packets this part is immediately thrown away after the merge.

LRO didn't have this problem because it directly read the headers
from the frags structure.

This patch attempts to address this by creating an interface
that allows GRO to access the headers in the first frag without
having to copy it.  Because all drivers that use frags place the
headers in the first frag this optimisation should be enough.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-01-29 16:33:03 -08:00
Benjamin Zores
9d8dba6c97 ipv4: fix infinite retry loop in IP-Config
Signed-off-by: Benjamin Zores <benjamin.zores@alcatel-lucent.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-01-29 16:19:13 -08:00
Dimitris Michailidis
9fa5fdf291 tcp: Fix length tcp_splice_data_recv passes to skb_splice_bits.
tcp_splice_data_recv has two lengths to consider: the len parameter it
gets from tcp_read_sock, which specifies the amount of data in the skb,
and rd_desc->count, which is the amount of data the splice caller still
wants.  Currently it passes just the latter to skb_splice_bits, which then
splices min(rd_desc->count, skb->len - offset) bytes.

Most of the time this is fine, except when the skb contains urgent data.
In that case len goes only up to the urgent byte and is less than
skb->len - offset.  By ignoring len tcp_splice_data_recv may a) splice
data tcp_read_sock told it not to, b) return to tcp_read_sock a value > len.

Now, tcp_read_sock doesn't handle used > len and leaves the socket in a
bad state (both sk_receive_queue and copied_seq are bad at that point)
resulting in duplicated data and corruption.

Fix by passing min(rd_desc->count, len) to skb_splice_bits.

Signed-off-by: Dimitris Michailidis <dm@chelsio.com>
Acked-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-01-26 22:15:31 -08:00
Eric Dumazet
98322f22ec udp: optimize bind(0) if many ports are in use
commit 9088c56095
(udp: Improve port randomization) introduced a regression for UDP bind() syscall
to null port (getting a random port) in case lot of ports are already in use.

This is because we do about 28000 scans of very long chains (220 sockets per chain),
with many spin_lock_bh()/spin_unlock_bh() calls.

Fix this using a bitmap (64 bytes for current value of UDP_HTABLE_SIZE)
so that we scan chains at most once.

Instead of 250 ms per bind() call, we get after patch a time of 2.9 ms 

Based on a report from Vitaly Mayatskikh

Reported-by: Vitaly Mayatskikh <v.mayatskih@gmail.com>
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Tested-by: Vitaly Mayatskikh <v.mayatskih@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-01-26 21:35:35 -08:00
Timo Teras
afcf12422e gre: optimize hash lookup
Instead of keeping candidate tunnel device from all categories,
keep only one candidate with best score. This optimizes stack
usage and speeds up exit code.

Signed-off-by: Timo Teras <timo.teras@iki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-01-26 20:56:10 -08:00
Benjamin Thery
4feb88e5c6 netns: ipmr: enable namespace support in ipv4 multicast routing code
This last patch makes the appropriate changes to use and propagate the
network namespace where needed in IPv4 multicast routing code.

This consists mainly in replacing all the remaining init_net occurences
with current netns pointer retrieved from sockets, net devices or
mfc_caches depending on the routines' contexts.

Some routines receive a new 'struct net' parameter to propagate the current
netns:
* vif_add/vif_delete
* ipmr_new_tunnel
* mroute_clean_tables
* ipmr_cache_find
* ipmr_cache_report
* ipmr_cache_unresolved
* ipmr_mfc_add/ipmr_mfc_delete
* ipmr_get_route
* rt_fill_info (in route.c)

Signed-off-by: Benjamin Thery <benjamin.thery@bull.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-01-22 13:57:41 -08:00
Benjamin Thery
f6bb451476 netns: ipmr: declare ipmr /proc/net entries per-namespace
Declare IPv4 multicast forwarding /proc/net entries per-namespace:
/proc/net/ip_mr_vif
/proc/net/ip_mr_cache

Signed-off-by: Benjamin Thery <benjamin.thery@bull.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-01-22 13:57:41 -08:00
Benjamin Thery
6c5143dbcf netns: ipmr: declare reg_vif_num per-namespace
Preliminary work to make IPv4 multicast routing netns-aware.

Declare variable 'reg_vif_num' per-namespace, move into struct netns_ipv4.

At the moment, this variable is only referenced in init_net.

Signed-off-by: Benjamin Thery <benjamin.thery@bull.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-01-22 13:57:40 -08:00
Benjamin Thery
6f9374a934 netns: ipmr: declare mroute_do_assert and mroute_do_pim per-namespace
Preliminary work to make IPv4 multicast routing netns-aware.

Declare IPv multicast routing variables 'mroute_do_assert' and
'mroute_do_pim' per-namespace in struct netns_ipv4.

At the moment, these variables are only referenced in init_net.

Signed-off-by: Benjamin Thery <benjamin.thery@bull.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-01-22 13:57:40 -08:00
Benjamin Thery
1e8fb3b6a4 netns: ipmr: declare counter cache_resolve_queue_len per-namespace
Preliminary work to make IPv4 multicast routing netns-aware.

Declare variable cache_resolve_queue_len per-namespace: move it into
struct netns_ipv4.

This variable counts the number of unresolved cache entries queued in the
list mfc_unres_queue. This list is kept global to all netns as the number
of entries per namespace is limited to 10 (hardcoded in routine
ipmr_cache_unresolved).
Entries belonging to different namespaces in mfc_unres_queue will be
identified by matching the mfc_net member introduced previously in
struct mfc_cache.

Keeping this list global to all netns, also allows us to keep a single
timer (ipmr_expire_timer) to handle their expiration.
In some places cache_resolve_queue_len value was tested for arming
or deleting the timer. These tests were equivalent to testing
mfc_unres_queue value instead and are replaced in this patch.

At the moment, cache_resolve_queue_len is only referenced in init_net.

Signed-off-by: Benjamin Thery <benjamin.thery@bull.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-01-22 13:57:39 -08:00
Benjamin Thery
2bb8b26c3e netns: ipmr: dynamically allocate mfc_cache_array
Preliminary work to make IPv4 multicast routing netns-aware.

Dynamically allocate IPv4 multicast forwarding cache, mfc_cache_array,
and move it to struct netns_ipv4.

At the moment, mfc_cache_array is only referenced in init_net.

Signed-off-by: Benjamin Thery <benjamin.thery@bull.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-01-22 13:57:38 -08:00
Benjamin Thery
5c0a66f5f3 netns: ipmr: store netns in struct mfc_cache
This patch stores into struct mfc_cache the network namespace each
mfc_cache belongs to. The new member is mfc_net.

mfc_net is assigned at cache allocation and doesn't change during
the rest of the cache entry life.
A new net parameter is added to ipmr_cache_alloc/ipmr_cache_alloc_unres.

This will help to retrieve the current netns around the IPv4 multicast
routing code.

At the moment, all mfc_cache are allocated in init_net.

Signed-off-by: Benjamin Thery <benjamin.thery@bull.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-01-22 13:57:36 -08:00
Benjamin Thery
cf958ae377 netns: ipmr: dynamically allocate vif_table
Preliminary work to make IPv6 multicast routing netns-aware.

Dynamically allocate interface table vif_table and move it to
struct netns_ipv4, and update MIF_EXISTS() macro.

At the moment, vif_table is only referenced in init_net.

Signed-off-by: Benjamin Thery <benjamin.thery@bull.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-01-22 13:57:34 -08:00
Benjamin Thery
70a269e6c9 netns: ipmr: allocate mroute_socket per-namespace.
Preliminary work to make IPv4 multicast routing netns-aware.

Make IPv4 multicast routing mroute_socket per-namespace,
moves it into struct netns_ipv4.

At the moment, mroute_socket is only referenced in init_net.

Signed-off-by: Benjamin Thery <benjamin.thery@bull.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-01-22 13:57:34 -08:00
Timo Teras
749c10f931 gre: strict physical device binding
Check the device on receive path and allow otherwise identical devices
as long as the physical device differs.

This is useful for NBMA tunnels, where you want to use different gre IP
for each public IP available via different physical devices.

Signed-off-by: Timo Teras <timo.teras@iki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-01-21 14:34:54 -08:00
Evgeniy Polyakov
a9d8f9110d inet: Allowing more than 64k connections and heavily optimize bind(0) time.
With simple extension to the binding mechanism, which allows to bind more
than 64k sockets (or smaller amount, depending on sysctl parameters),
we have to traverse the whole bind hash table to find out empty bucket.
And while it is not a problem for example for 32k connections, bind()
completion time grows exponentially (since after each successful binding
we have to traverse one bucket more to find empty one) even if we start
each time from random offset inside the hash table.

So, when hash table is full, and we want to add another socket, we have
to traverse the whole table no matter what, so effectivelly this will be
the worst case performance and it will be constant.

Attached picture shows bind() time depending on number of already bound
sockets.

Green area corresponds to the usual binding to zero port process, which
turns on kernel port selection as described above. Red area is the bind
process, when number of reuse-bound sockets is not limited by 64k (or
sysctl parameters). The same exponential growth (hidden by the green
area) before number of ports reaches sysctl limit.

At this time bind hash table has exactly one reuse-enbaled socket in a
bucket, but it is possible that they have different addresses. Actually
kernel selects the first port to try randomly, so at the beginning bind
will take roughly constant time, but with time number of port to check
after random start will increase. And that will have exponential growth,
but because of above random selection, not every next port selection
will necessary take longer time than previous. So we have to consider
the area below in the graph (if you could zoom it, you could find, that
there are many different times placed there), so area can hide another.

Blue area corresponds to the port selection optimization.

This is rather simple design approach: hashtable now maintains (unprecise
and racely updated) number of currently bound sockets, and when number
of such sockets becomes greater than predefined value (I use maximum
port range defined by sysctls), we stop traversing the whole bind hash
table and just stop at first matching bucket after random start. Above
limit roughly corresponds to the case, when bind hash table is full and
we turned on mechanism of allowing to bind more reuse-enabled sockets,
so it does not change behaviour of other sockets.

Signed-off-by: Evgeniy Polyakov <zbr@ioremap.net>
Tested-by: Denys Fedoryschenko <denys@visp.net.lb>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-01-21 14:34:31 -08:00
Herbert Xu
4e704ee3c2 gso: Ensure that the packet is long enough
When we get a GSO packet from an untrusted source, we need to
ensure that it is sufficiently long so that we don't end up
crashing.

Based on discovery and patch by Ian Campbell.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Tested-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-01-14 20:41:12 -08:00
Willy Tarreau
33966dd0e2 tcp: splice as many packets as possible at once
As spotted by Willy Tarreau, current splice() from tcp socket to pipe is not
optimal. It processes at most one segment per call.
This results in low performance and very high overhead due to syscall rate
when splicing from interfaces which do not support LRO.

Willy provided a patch inside tcp_splice_read(), but a better fix
is to let tcp_read_sock() process as many segments as possible, so
that tcp_rcv_space_adjust() and tcp_cleanup_rbuf() are called less
often.

With this change, splice() behaves like tcp_recvmsg(), being able
to consume many skbs in one system call. With typical 1460 bytes
of payload per frame, that means splice(SPLICE_F_NONBLOCK) can return
16*1460 = 23360 bytes.

Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-01-13 16:04:36 -08:00
Patrick McHardy
71320afcdb netfilter 06/09: nf_conntrack: fix ICMP/ICMPv6 timeout sysctls on big-endian
An old bug crept back into the ICMP/ICMPv6 conntrack protocols: the timeout
values are defined as unsigned longs, the sysctl's maxsize is set to
sizeof(unsigned int). Use unsigned int for the timeout values as in the
other conntrack protocols.

Reported-by: Jean-Mickael Guerin <jean-mickael.guerin@6wind.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-01-12 21:18:35 -08:00