Commit Graph

121 Commits

Author SHA1 Message Date
Miquel van Smoorenburg
57413ebc4e tcp: calculate tcp_mem based on low memory instead of all memory
The tcp_mem array which contains limits on the total amount of memory
used by TCP sockets is calculated based on nr_all_pages.  On a 32 bits
x86 system, we should base this on the number of lowmem pages.

Signed-off-by: Miquel van Smoorenburg <miquels@cistron.nl>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-06-27 17:23:57 -07:00
David S. Miller
ec0a196626 tcp: Revert 'process defer accept as established' changes.
This reverts two changesets, ec3c0982a2
("[TCP]: TCP_DEFER_ACCEPT updates - process as established") and
the follow-on bug fix 9ae27e0adb
("tcp: Fix slab corruption with ipv6 and tcp6fuzz").

This change causes several problems, first reported by Ingo Molnar
as a distcc-over-loopback regression where connections were getting
stuck.

Ilpo Järvinen first spotted the locking problems.  The new function
added by this code, tcp_defer_accept_check(), only has the
child socket locked, yet it is modifying state of the parent
listening socket.

Fixing that is non-trivial at best, because we can't simply just grab
the parent listening socket lock at this point, because it would
create an ABBA deadlock.  The normal ordering is parent listening
socket --> child socket, but this code path would require the
reverse lock ordering.

Next is a problem noticed by Vitaliy Gusev, he noted:

----------------------------------------
>--- a/net/ipv4/tcp_timer.c
>+++ b/net/ipv4/tcp_timer.c
>@@ -481,6 +481,11 @@ static void tcp_keepalive_timer (unsigned long data)
> 		goto death;
> 	}
>
>+	if (tp->defer_tcp_accept.request && sk->sk_state == TCP_ESTABLISHED) {
>+		tcp_send_active_reset(sk, GFP_ATOMIC);
>+		goto death;

Here socket sk is not attached to listening socket's request queue. tcp_done()
will not call inet_csk_destroy_sock() (and tcp_v4_destroy_sock() which should
release this sk) as socket is not DEAD. Therefore socket sk will be lost for
freeing.
----------------------------------------

Finally, Alexey Kuznetsov argues that there might not even be any
real value or advantage to these new semantics even if we fix all
of the bugs:

----------------------------------------
Hiding from accept() sockets with only out-of-order data only
is the only thing which is impossible with old approach. Is this really
so valuable? My opinion: no, this is nothing but a new loophole
to consume memory without control.
----------------------------------------

So revert this thing for now.

Signed-off-by: David S. Miller <davem@davemloft.net>
2008-06-12 16:34:35 -07:00
Octavian Purdila
293ad60401 tcp: Fix for race due to temporary drop of the socket lock in skb_splice_bits.
skb_splice_bits temporary drops the socket lock while iterating over
the socket queue in order to break a reverse locking condition which
happens with sendfile. This, however, opens a window of opportunity
for tcp_collapse() to aggregate skbs and thus potentially free the
current skb used in skb_splice_bits and tcp_read_sock.

This patch fixes the problem by (re-)getting the same "logical skb"
after the lock has been temporary dropped.

Based on idea and initial patch from Evgeniy Polyakov.

Signed-off-by: Octavian Purdila <opurdila@ixiacom.com>
Acked-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-06-04 15:45:58 -07:00
Satoru SATOH
1f29b0584d tcp: Trivial fix to correct function name in a comment in net/ipv4/tcp.c
This is a trivial fix to correct function name in a comment in
net/ipv4/tcp.c.

Signed-off-by: Satoru SATOH <satoru.satoh@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-04-21 02:27:58 -07:00
David S. Miller
06802a819a Merge branch 'master' of ../net-2.6/
Conflicts:

	net/ipv6/ndisc.c
2008-03-23 22:54:03 -07:00
Herbert Xu
69d1506731 [TCP]: Let skbs grow over a page on fast peers
While testing the virtio-net driver on KVM with TSO I noticed
that TSO performance with a 1500 MTU is significantly worse
compared to the performance of non-TSO with a 16436 MTU.  The
packet dump shows that most of the packets sent are smaller
than a page.

Looking at the code this actually is quite obvious as it always
stop extending the packet if it's the first packet yet to be
sent and if it's larger than the MSS.  Since each extension is
bound by the page size, this means that (given a 1500 MTU) we're
very unlikely to construct packets greater than a page, provided
that the receiver and the path is fast enough so that packets can
always be sent immediately.

The fix is also quite obvious.  The push calls inside the loop
is just an optimisation so that we don't end up doing all the
sending at the end of the loop.  Therefore there is no specific
reason why it has to do so at MSS boundaries.  For TSO, the
most natural extension of this optimisation is to do the pushing
once the skb exceeds the TSO size goal.

This is what the patch does and testing with KVM shows that the
TSO performance with a 1500 MTU easily surpasses that of a 16436
MTU and indeed the packet sizes sent are generally larger than
16436.

I don't see any obvious downsides for slower peers or connections,
but it would be prudent to test this extensively to ensure that
those cases don't regress.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-22 15:47:05 -07:00
Patrick McManus
ec3c0982a2 [TCP]: TCP_DEFER_ACCEPT updates - process as established
Change TCP_DEFER_ACCEPT implementation so that it transitions a
connection to ESTABLISHED after handshake is complete instead of
leaving it in SYN-RECV until some data arrvies. Place connection in
accept queue when first data packet arrives from slow path.

Benefits:
  - established connection is now reset if it never makes it
   to the accept queue

 - diagnostic state of established matches with the packet traces
   showing completed handshake

 - TCP_DEFER_ACCEPT timeouts are expressed in seconds and can now be
   enforced with reasonable accuracy instead of rounding up to next
   exponential back-off of syn-ack retry.

Signed-off-by: Patrick McManus <mcmanus@ducksong.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-21 16:33:01 -07:00
Arnaldo Carvalho de Melo
ab1e0a13d7 [SOCK] proto: Add hashinfo member to struct proto
This way we can remove TCP and DCCP specific versions of

sk->sk_prot->get_port: both v4 and v6 use inet_csk_get_port
sk->sk_prot->hash:     inet_hash is directly used, only v6 need
                       a specific version to deal with mapped sockets
sk->sk_prot->unhash:   both v4 and v6 use inet_hash directly

struct inet_connection_sock_af_ops also gets a new member, bind_conflict, so
that inet_csk_get_port can find the per family routine.

Now only the lookup routines receive as a parameter a struct inet_hashtable.

With this we further reuse code, reducing the difference among INET transport
protocols.

Eventually work has to be done on UDP and SCTP to make them share this
infrastructure and get as a bonus inet_diag interfaces so that iproute can be
used with these protocols.

net-2.6/net/ipv4/inet_hashtables.c:
  struct proto			     |   +8
  struct inet_connection_sock_af_ops |   +8
 2 structs changed
  __inet_hash_nolisten               |  +18
  __inet_hash                        | -210
  inet_put_port                      |   +8
  inet_bind_bucket_create            |   +1
  __inet_hash_connect                |   -8
 5 functions changed, 27 bytes added, 218 bytes removed, diff: -191

net-2.6/net/core/sock.c:
  proto_seq_show                     |   +3
 1 function changed, 3 bytes added, diff: +3

net-2.6/net/ipv4/inet_connection_sock.c:
  inet_csk_get_port                  |  +15
 1 function changed, 15 bytes added, diff: +15

net-2.6/net/ipv4/tcp.c:
  tcp_set_state                      |   -7
 1 function changed, 7 bytes removed, diff: -7

net-2.6/net/ipv4/tcp_ipv4.c:
  tcp_v4_get_port                    |  -31
  tcp_v4_hash                        |  -48
  tcp_v4_destroy_sock                |   -7
  tcp_v4_syn_recv_sock               |   -2
  tcp_unhash                         | -179
 5 functions changed, 267 bytes removed, diff: -267

net-2.6/net/ipv6/inet6_hashtables.c:
  __inet6_hash |   +8
 1 function changed, 8 bytes added, diff: +8

net-2.6/net/ipv4/inet_hashtables.c:
  inet_unhash                        | +190
  inet_hash                          | +242
 2 functions changed, 432 bytes added, diff: +432

vmlinux:
 16 functions changed, 485 bytes added, 492 bytes removed, diff: -7

/home/acme/git/net-2.6/net/ipv6/tcp_ipv6.c:
  tcp_v6_get_port                    |  -31
  tcp_v6_hash                        |   -7
  tcp_v6_syn_recv_sock               |   -9
 3 functions changed, 47 bytes removed, diff: -47

/home/acme/git/net-2.6/net/dccp/proto.c:
  dccp_destroy_sock                  |   -7
  dccp_unhash                        | -179
  dccp_hash                          |  -49
  dccp_set_state                     |   -7
  dccp_done                          |   +1
 5 functions changed, 1 bytes added, 242 bytes removed, diff: -241

/home/acme/git/net-2.6/net/dccp/ipv4.c:
  dccp_v4_get_port                   |  -31
  dccp_v4_request_recv_sock          |   -2
 2 functions changed, 33 bytes removed, diff: -33

/home/acme/git/net-2.6/net/dccp/ipv6.c:
  dccp_v6_get_port                   |  -31
  dccp_v6_hash                       |   -7
  dccp_v6_request_recv_sock          |   +5
 3 functions changed, 5 bytes added, 38 bytes removed, diff: -33

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-02-03 04:28:52 -08:00
Ilpo Järvinen
490d504693 [TCP]: Uninline tcp_set_state
net/ipv4/tcp.c:
  tcp_close_state | -226
  tcp_done        | -145
  tcp_close       | -564
  tcp_disconnect  | -141
 4 functions changed, 1076 bytes removed, diff: -1076

net/ipv4/tcp_input.c:
  tcp_fin               |  -86
  tcp_rcv_state_process | -164
 2 functions changed, 250 bytes removed, diff: -250

net/ipv4/tcp_ipv4.c:
  tcp_v4_connect | -209
 1 function changed, 209 bytes removed, diff: -209

net/ipv4/arp.c:
  arp_ignore |   +5
 1 function changed, 5 bytes added, diff: +5

net/ipv6/tcp_ipv6.c:
  tcp_v6_connect | -158
 1 function changed, 158 bytes removed, diff: -158

net/sunrpc/xprtsock.c:
  xs_sendpages |   -2
 1 function changed, 2 bytes removed, diff: -2

net/dccp/ccids/ccid3.c:
  ccid3_update_send_interval |   +7
 1 function changed, 7 bytes added, diff: +7

net/ipv4/tcp.c:
  tcp_set_state | +238
 1 function changed, 238 bytes added, diff: +238

built-in.o:
 12 functions changed, 250 bytes added, 1695 bytes removed, diff: -1445

I've no explanation why some unrelated changes seem to occur
consistently as well (arp_ignore, ccid3_update_send_interval;
I checked the arp_ignore asm and it seems to be due to some
reordered of operation order causing some extra opcodes to be
generated). Still, the benefits are pretty obvious from the
codiff's results.

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 15:01:47 -08:00
Ilpo Järvinen
4828e7f49a [TCP]: Remove TCPCB_URG & TCPCB_AT_TAIL as unnecessary
The snd_up check should be enough. I suspect this has been
there to provide a minor optimization in clean_rtx_queue which
used to have a small if (!->sacked) block which could skip
snd_up check among the other work.

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 15:00:23 -08:00
Hideo Aoki
3ab224be6d [NET] CORE: Introducing new memory accounting interface.
This patch introduces new memory accounting functions for each network
protocol. Most of them are renamed from memory accounting functions
for stream protocols. At the same time, some stream memory accounting
functions are removed since other functions do same thing.

Renaming:
	sk_stream_free_skb()		->	sk_wmem_free_skb()
	__sk_stream_mem_reclaim()	->	__sk_mem_reclaim()
	sk_stream_mem_reclaim()		->	sk_mem_reclaim()
	sk_stream_mem_schedule 		->    	__sk_mem_schedule()
	sk_stream_pages()      		->	sk_mem_pages()
	sk_stream_rmem_schedule()	->	sk_rmem_schedule()
	sk_stream_wmem_schedule()	->	sk_wmem_schedule()
	sk_charge_skb()			->	sk_mem_charge()

Removeing
	sk_stream_rfree():	consolidates into sock_rfree()
	sk_stream_set_owner_r(): consolidates into skb_set_owner_r()
	sk_stream_mem_schedule()

The following functions are added.
    	sk_has_account(): check if the protocol supports accounting
	sk_mem_uncharge(): do the opposite of sk_mem_charge()

In addition, to achieve consolidation, updating sk_wmem_queued is
removed from sk_mem_charge().

Next, to consolidate memory accounting functions, this patch adds
memory accounting calls to network core functions. Moreover, present
memory accounting call is renamed to new accounting call.

Finally we replace present memory accounting calls with new interface
in TCP and SCTP.

Signed-off-by: Takahiro Yasui <tyasui@redhat.com>
Signed-off-by: Hideo Aoki <haoki@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 15:00:18 -08:00
Pavel Emelyanov
1f9e636ea2 [TCP]: Use BUILD_BUG_ON for tcp_skb_cb size checking
The sizeof(struct tcp_skb_cb) should not be less than the
sizeof(skb->cb). This is checked in net/ipv4/tcp.c, but
this check can be made more gracefully.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:57:07 -08:00
Pavel Emelyanov
df97c708d5 [NET]: Eliminate unused argument from sk_stream_alloc_pskb
The 3rd argument is always zero (according to grep :) Eliminate
it and merge the function with sk_stream_alloc_skb.

This saves 44 more bytes, and together with the previous patch
we have:

add/remove: 1/0 grow/shrink: 0/8 up/down: 183/-751 (-568)
function                                     old     new   delta
sk_stream_alloc_skb                            -     183    +183
ip_rt_init                                   529     525      -4
arp_ignore                                   112     107      -5
__inet_lookup_listener                       284     274     -10
tcp_sendmsg                                 2583    2481    -102
tcp_sendpage                                1449    1300    -149
tso_fragment                                 417     258    -159
tcp_fragment                                1149     988    -161
__tcp_push_pending_frames                   1998    1837    -161

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:55:08 -08:00
Pavel Emelyanov
f561d0f27d [NET]: Uninline the sk_stream_alloc_pskb
This function seems too big for inlining. Indeed, it saves
half-a-kilo when uninlined:

add/remove: 1/0 grow/shrink: 0/7 up/down: 195/-719 (-524)
function                                     old     new   delta
sk_stream_alloc_pskb                           -     195    +195
ip_rt_init                                   529     525      -4
__inet_lookup_listener                       284     274     -10
tcp_sendmsg                                 2583    2486     -97
tcp_sendpage                                1449    1305    -144
tso_fragment                                 417     267    -150
tcp_fragment                                1149     992    -157
__tcp_push_pending_frames                   1998    1841    -157

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:55:07 -08:00
Adrian Bunk
6ff7751d06 [TCP]: Make tcp_splice_data_recv() static.
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:53:32 -08:00
Jens Axboe
9c55e01c0c [TCP]: Splice receive support.
Support for network splice receive.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 14:53:31 -08:00
Eric Dumazet
230140cffa [INET]: Remove per bucket rwlock in tcp/dccp ehash table.
As done two years ago on IP route cache table (commit
22c047ccbc) , we can avoid using one
lock per hash bucket for the huge TCP/DCCP hash tables.

On a typical x86_64 platform, this saves about 2MB or 4MB of ram, for
litle performance differences. (we hit a different cache line for the
rwlock, but then the bucket cache line have a better sharing factor
among cpus, since we dirty it less often). For netstat or ss commands
that want a full scan of hash table, we perform fewer memory accesses.

Using a 'small' table of hashed rwlocks should be more than enough to
provide correct SMP concurrency between different buckets, without
using too much memory. Sizing of this table depends on
num_possible_cpus() and various CONFIG settings.

This patch provides some locking abstraction that may ease a future
work using a different model for TCP/DCCP table.

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-11-07 04:15:11 -08:00
Jean Delvare
0ccfe61803 [TCP]: Saner thash_entries default with much memory.
On systems with a very large amount of memory, the heuristics in
alloc_large_system_hash() result in a very large TCP established hash
table: 16 millions of entries for a 128 GB ia64 system. This makes
reading from /proc/net/tcp pretty slow (well over a second) and as a
result netstat is slow on these machines. I know that /proc/net/tcp is
deprecated in favor of tcp_diag, however at the moment netstat only
knows of the former.

I am skeptical that such a large TCP established hash is often needed.
Just because a system has a lot of memory doesn't imply that it will
have several millions of concurrent TCP connections. Thus I believe
that we should put an arbitrary high limit to the size of the TCP
established hash by default. Users who really need a bigger hash can
always use the thash_entries boot parameter to get more.

I propose 2 millions of entries as the arbitrary high limit. This
makes /proc/net/tcp reasonably fast on the system in question (0.2 s)
while being still large enough for me to be confident that network
performance won't suffer.

This is just one way to limit the hash size, there are others; I am not
familiar enough with the TCP code to decide which is best. Thus, I
would welcome the proposals of alternatives.

[ 2 million is still too large, thus I've modified the limit in the
  change to be '512 * 1024'. -DaveM ]

Signed-off-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-30 00:59:25 -07:00
Pavel Emelyanov
ba25f9dcc4 Use helpers to obtain task pid in printks
The task_struct->pid member is going to be deprecated, so start
using the helpers (task_pid_nr/task_pid_vnr/task_pid_nr_ns) in
the kernel.

The first thing to start with is the pid, printed to dmesg - in
this case we may safely use task_pid_nr(). Besides, printks produce
more (much more) than a half of all the explicit pid usage.

[akpm@linux-foundation.org: git-drm went and changed lots of stuff]
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Cc: Dave Airlie <airlied@linux.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-19 11:53:43 -07:00
Rick Jones
5ee3afba88 [TCP]: Return useful listenq info in tcp_info and INET_DIAG_INFO.
Return some useful information such as the maximum listen backlog and
the current listen backlog in the tcp_info structure and
INET_DIAG_INFO.

Signed-off-by: Rick Jones <rick.jones2@hp.com>
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:51:35 -07:00
Ilpo Järvinen
172589ccdd [NET]: DIV_ROUND_UP cleanup (part two)
Hopefully captured all single statement cases under net/. I'm
not too sure if there is some policy about #includes that are
"guaranteed" (ie., in the current tree) to be available through
some other #included header, so I just added linux/kernel.h to
each changed file that didn't #include it previously.

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:48:37 -07:00
Ilpo Järvinen
e60402d0a9 [TCP]: Move sack_ok access to obviously named funcs & cleanup
Previously code had IsReno/IsFack defined as macros that were
local to tcp_input.c though sack_ok field has user elsewhere too
for the same purpose. This changes them to static inlines as
preferred according the current coding style and unifies the
access to sack_ok across multiple files. Magic bitops of sack_ok
for FACK and DSACK are also abstracted to functions with
appropriate names.

Note:
- One sack_ok = 1 remains but that's self explanary, i.e., it
  enables sack
- Couple of !IsReno cases are changed to tcp_is_sack
- There were no users for IsDSack => I dropped it

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:48:00 -07:00
David S. Miller
3516ffb0fe [TCP]: Invoke tcp_sendmsg() directly, do not use inet_sendmsg().
As discovered by Evegniy Polyakov, if we try to sendmsg after
a connection reset, we can do incredibly stupid things.

The core issue is that inet_sendmsg() tries to autobind the
socket, but we should never do that for TCP.  Instead we should
just go straight into TCP's sendmsg() code which will do all
of the necessary state and pending socket error checks.

TCP's sendpage already directly vectors to tcp_sendpage(), so this
merely brings sendmsg() in line with that.

Signed-off-by: David S. Miller <davem@davemloft.net>
2007-08-02 19:42:28 -07:00
Paul Mundt
20c2df83d2 mm: Remove slab destructors from kmem_cache_create().
Slab destructors were no longer supported after Christoph's
c59def9f22 change. They've been
BUGs for both slab and slub, and slob never supported them
either.

This rips out support for the dtor pointer from kmem_cache_create()
completely and fixes up every single callsite in the kernel (there were
about 224, not including the slab allocator definitions themselves,
or the documentation references).

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2007-07-20 10:11:58 +09:00
Andrew Morton
e00c5d8b4d I/OAT: warning fix
net/ipv4/tcp.c: In function 'tcp_recvmsg':
net/ipv4/tcp.c:1111: warning: unused variable 'available'

Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Chris Leech <christopher.leech@intel.com>
2007-07-11 16:10:53 -07:00
Chris Leech
2b1244a43b I/OAT: Only offload copies for TCP when there will be a context switch
The performance wins come with having the DMA copy engine doing the copies
in parallel with the context switch.  If there is enough data ready on the
socket at recv time just use a regular copy.

Signed-off-by: Chris Leech <christopher.leech@intel.com>
2007-07-11 16:10:53 -07:00
Jens Axboe
ddb61a57bb [TCP] tcp_read_sock: Allow recv_actor() return return negative error value.
tcp_read_sock() currently assumes that the recv_actor() only returns
number of bytes copied. For network splice receive, we may have to
return an error in some cases. So allow the actor to return a negative
error value.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-06-23 23:07:50 -07:00
Mark Glines
3f196eb519 [TCP]: Use default 32768-61000 outgoing port range in all cases.
This diff changes the default port range used for outgoing connections,
from "use 32768-61000 in most cases, but use N-4999 on small boxes
(where N is a multiple of 1024, depending on just *how* small the box
is)" to just "use 32768-61000 in all cases".

I don't believe there are any drawbacks to this change, and it keeps
outgoing connection ports farther away from the mess of
IANA-registered ports.

Signed-off-by: Mark Glines <mark@glines.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-06-03 18:08:43 -07:00
Pavel Emelianov
e4fd5da39f [TCP]: Consolidate checking for tcp orphan count being too big.
tcp_out_of_resources() and tcp_close() perform the
same checking of number of orphan sockets. Move this
code into common place.

Signed-off-by: Pavel Emelianov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-05-31 01:23:34 -07:00
Randy Dunlap
e63340ae6b header cleaning: don't include smp_lock.h when not used
Remove includes of <linux/smp_lock.h> where it is not used/needed.
Suggested by Al Viro.

Builds cleanly on x86_64, i386, alpha, ia64, powerpc, sparc,
sparc64, and arm (all 59 defconfigs).

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-08 11:15:07 -07:00
Srinivas Aji
b40b4f79ce [TCP]: zero out rx_opt in tcp_disconnect()
When the server drops its connection, NFS client reconnects using the
same socket after disconnecting. If the new connection's SYN,ACK
doesn't contain the TCP timestamp option and the old connection's did,
tp->tcp_header_len is recomputed assuming no timestamp header but
tp->rx_opt.tstamp_ok remains set. Then tcp_build_and_update_options()
adds in a timestamp option past the end of the allocated TCP header,
overwriting TCP data, or when the data is in skb_shinfo(skb)->frags[],
overwriting skb_shinfo(skb) causing a crash soon after. (The issue was
debugged from such a crash.)

Similarly, wscale_ok and sack_ok also get set based on the SYN,ACK
packet but not reset on disconnect, since they are zeroed out at
initialization. The patch zeroes out the entire tp->rx_opt struct in
tcp_disconnect() to avoid this sort of problem.

Signed-off-by: Srinivas Aji <Aji_Srinivas@emc.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-05-03 17:32:28 -07:00
Gerrit Renker
65bb723c95 [TCP]: Update references in two old comments
This updates references to drafts in comments which must be about 10
years old.  Internet draft draft-ietf-tcpimpl-prob-03.txt expired in 1998
and was replaced by RFC 2525 in March 1999.

Section 3.10 of the draft maps almost identically into section 2.17 of RFC
2525: both are entitled "Failure to RST on close with data pending", the
differences in text body amount to a typo and minor sentence change.

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-28 21:21:46 -07:00
Ilpo Järvinen
9e412ba763 [TCP]: Sed magic converts func(sk, tp, ...) -> func(sk, ...)
This is (mostly) automated change using magic:

sed -e '/struct sock \*sk/ N' -e '/struct sock \*sk/ N'
    -e '/struct sock \*sk/ N' -e '/struct sock \*sk/ N'
    -e 's|struct sock \*sk,[\n\t ]*struct tcp_sock \*tp\([^{]*\n{\n\)|
	  struct sock \*sk\1\tstruct tcp_sock *tp = tcp_sk(sk);\n|g'
    -e 's|struct sock \*sk, struct tcp_sock \*tp|
	  struct sock \*sk|g' -e 's|sk, tp\([^-]\)|sk\1|g'

Fixed four unused variable (tp) warnings that were introduced.

In addition, manually added newlines after local variables and
tweaked function arguments positioning.

$ gcc --version
gcc (GCC) 4.1.1 20060525 (Red Hat 4.1.1-1)
...
$ codiff -fV built-in.o.old built-in.o.new
net/ipv4/route.c:
  rt_cache_flush |  +14
 1 function changed, 14 bytes added

net/ipv4/tcp.c:
  tcp_setsockopt |   -5
  tcp_sendpage   |  -25
  tcp_sendmsg    |  -16
 3 functions changed, 46 bytes removed

net/ipv4/tcp_input.c:
  tcp_try_undo_recovery |   +3
  tcp_try_undo_dsack    |   +2
  tcp_mark_head_lost    |  -12
  tcp_ack               |  -15
  tcp_event_data_recv   |  -32
  tcp_rcv_state_process |  -10
  tcp_rcv_established   |   +1
 7 functions changed, 6 bytes added, 69 bytes removed, diff: -63

net/ipv4/tcp_output.c:
  update_send_head          |   -9
  tcp_transmit_skb          |  +19
  tcp_cwnd_validate         |   +1
  tcp_write_wakeup          |  -17
  __tcp_push_pending_frames |  -25
  tcp_push_one              |   -8
  tcp_send_fin              |   -4
 7 functions changed, 20 bytes added, 63 bytes removed, diff: -43

built-in.o.new:
 18 functions changed, 40 bytes added, 178 bytes removed, diff: -138

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:29:34 -07:00
Andi Kleen
4ac02bab77 [TCP]: Uninline tcp_done().
The function is quite big and has several call sites and nothing
to collapse by compiler optimization on inlining.

Besides it's nicer to read in a in .c file.

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:29:25 -07:00
Stephen Hemminger
3ff50b7997 [NET]: cleanup extra semicolons
Spring cleaning time...

There seems to be a lot of places in the network code that have
extra bogus semicolons after conditionals.  Most commonly is a
bogus semicolon after: switch() { }

Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:29:24 -07:00
Eric Dumazet
4103f8cd5c [TCP]: tcp_memory_pressure and tcp_socket are__read_mostly candidates
tcp_memory_pressure and tcp_socket currently share a cache line with tcp_memory_allocated, tcp_sockets_allocated.
(Very hot cache line)
It makes sense to declare these variables as __read_mostly, to avoid false sharing on SMP.

ffffffff8081d9c0 B tcp_orphan_count
ffffffff8081d9c4 B tcp_memory_allocated
ffffffff8081d9c8 B tcp_sockets_allocated
ffffffff8081d9cc B tcp_memory_pressure
ffffffff8081d9d0 b tcp_md5sig_users
ffffffff8081d9d8 b tcp_md5sig_pool
ffffffff8081d9e0 b warntime.31570
ffffffff8081d9e8 b tcp_socket

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:28:19 -07:00
Arnaldo Carvalho de Melo
27a884dc3c [SK_BUFF]: Convert skb->tail to sk_buff_data_t
So that it is also an offset from skb->head, reduces its size from 8 to 4 bytes
on 64bit architectures, allowing us to combine the 4 bytes hole left by the
layer headers conversion, reducing struct sk_buff size to 256 bytes, i.e. 4
64byte cachelines, and since the sk_buff slab cache is SLAB_HWCACHE_ALIGN...
:-)

Many calculations that previously required that skb->{transport,network,
mac}_header be first converted to a pointer now can be done directly, being
meaningful as offsets or pointers.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:26:28 -07:00
Arnaldo Carvalho de Melo
9c70220b73 [SK_BUFF]: Introduce skb_transport_header(skb)
For the places where we need a pointer to the transport header, it is
still legal to touch skb->h.raw directly if just adding to,
subtracting from or setting it to another layer header.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:25:31 -07:00
Arnaldo Carvalho de Melo
aa8223c7bb [SK_BUFF]: Introduce tcp_hdr(), remove skb->h.th
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:25:26 -07:00
David S. Miller
fe067e8ab5 [TCP]: Abstract out all write queue operations.
This allows the write queue implementation to be changed,
for example, to one which allows fast interval searching.

Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:24:02 -07:00
John Heffner
53cdcc04c1 [TCP]: Fix tcp_mem[] initialization.
Change tcp_mem initialization function.  The fraction of total memory
is now a continuous function of memory size, and independent of page
size.

Signed-off-by: John Heffner <jheffner@psc.edu>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-03-16 15:04:03 -07:00
David S. Miller
2c4f6219ac [TCP]: Fix MD5 signature pool locking.
The locking calls assumed that these code paths were only
invoked in software interrupt context, but that isn't true.

Therefore we need to use spin_{lock,unlock}_bh() throughout.

Signed-off-by: David S. Miller <davem@davemloft.net>
2007-02-26 11:42:48 -08:00
YOSHIFUJI Hideaki
e905a9edab [NET] IPV4: Fix whitespace errors.
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-02-10 23:19:39 -08:00
Eric Dumazet
dbca9b2750 [NET]: change layout of ehash table
ehash table layout is currently this one :

First half of this table is used by sockets not in TIME_WAIT state
Second half of it is used by sockets in TIME_WAIT state.

This is non optimal because of for a given hash or socket, the two chain heads 
are located in separate cache lines.
Moreover the locks of the second half are never used.

If instead of this halving, we use two list heads in inet_ehash_bucket instead 
of only one, we probably can avoid one cache miss, and reduce ram usage, 
particularly if sizeof(rwlock_t) is big (various CONFIG_DEBUG_SPINLOCK, 
CONFIG_DEBUG_LOCK_ALLOC settings). So we still halves the table but we keep 
together related chains to speedup lookups and socket state change.

In this patch I did not try to align struct inet_ehash_bucket, but a future 
patch could try to make this structure have a convenient size (a power of two 
or a multiple of L1_CACHE_SIZE).
I guess rwlock will just vanish as soon as RCU is plugged into ehash :) , so 
maybe we dont need to scratch our heads to align the bucket...

Note : In case struct inet_ehash_bucket is not a power of two, we could 
probably change alloc_large_system_hash() (in case it use __get_free_pages()) 
to free the unused space. It currently allocates a big zone, but the last 
quarter of it could be freed. Again, this should be a temporary 'problem'.

Patch tested on ipv4 tcp only, but should be OK for IPV6 and DCCP.

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-02-08 14:16:46 -08:00
David S. Miller
6931ba7cef [TCP]: Fix oops caused by __tcp_put_md5sig_pool()
It should call tcp_free_md5sig_pool() not __tcp_free_md5sig_pool()
so that it does proper refcounting.

Signed-off-by: David S. Miller <davem@davemloft.net>
2006-12-13 16:48:26 -08:00
Adrian Bunk
f5b99bcddd [NET]: Possible cleanups.
This patch contains the following possible cleanups:
- make the following needlessly global functions statis:
  - ipv4/tcp.c: __tcp_alloc_md5sig_pool()
  - ipv4/tcp_ipv4.c: tcp_v4_reqsk_md5_lookup()
  - ipv4/udplite.c: udplite_rcv()
  - ipv4/udplite.c: udplite_err()
- make the following needlessly global structs static:
  - ipv4/tcp_ipv4.c: tcp_request_sock_ipv4_ops
  - ipv4/tcp_ipv4.c: tcp_sock_ipv4_specific
  - ipv6/tcp_ipv6.c: tcp_request_sock_ipv6_ops
- net/ipv{4,6}/udplite.c: remove inline's from static functions
                          (gcc should know best when to inline them)

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-12-02 21:31:51 -08:00
Arnaldo Carvalho de Melo
352d48008b [TCP]: Tidy up skb_entail
Heck, it even saves us some few bytes:

[acme@newtoy net-2.6.20]$ codiff -f /tmp/tcp.o.before ../OUTPUT/qemu/net-2.6.20/net/ipv4/tcp.o
/pub/scm/linux/kernel/git/acme/net-2.6.20/net/ipv4/tcp.c:
  tcp_sendpage |   -7
  tcp_sendmsg  |   -5
 2 functions changed, 12 bytes removed
[acme@newtoy net-2.6.20]$

Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
2006-12-02 21:24:03 -08:00
Al Viro
d3bc23e7ee [NET]: Annotate callers of csum_fold() in net/*
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-12-02 21:23:27 -08:00
YOSHIFUJI Hideaki
cfb6eeb4c8 [TCP]: MD5 Signature Option (RFC2385) support.
Based on implementation by Rick Payne.

Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-12-02 21:22:39 -08:00
John Heffner
52bf376c63 [TCP]: Fix up sysctl_tcp_mem initialization.
Fix up tcp_mem initial settings to take into account the size of the
hash entries (different on SMP and non-SMP systems).

Signed-off-by: John Heffner <jheffner@psc.edu>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-11-15 21:18:51 -08:00