Commit Graph

465 Commits

Author SHA1 Message Date
David S. Miller 14e50e57ae [XFRM]: Allow packet drops during larval state resolution.
The current IPSEC rule resolution behavior we have does not work for a
lot of people, even though technically it's an improvement from the
-EAGAIN buisness we had before.

Right now we'll block until the key manager resolves the route.  That
works for simple cases, but many folks would rather packets get
silently dropped until the key manager resolves the IPSEC rules.

We can't tell these folks to "set the socket non-blocking" because
they don't have control over the non-block setting of things like the
sockets used to resolve DNS deep inside of the resolver libraries in
libc.

With that in mind I coded up the patch below with some help from
Herbert Xu which provides packet-drop behavior during larval state
resolution, controllable via sysctl and off by default.

This lays the framework to either:

1) Make this default at some point or...

2) Move this logic into xfrm{4,6}_policy.c and implement the
   ARP-like resolution queue we've all been dreaming of.
   The idea would be to queue packets to the policy, then
   once the larval state is resolved by the key manager we
   re-resolve the route and push the packets out.  The
   packets would timeout if the rule didn't get resolved
   in a certain amount of time.

Signed-off-by: David S. Miller <davem@davemloft.net>
2007-05-24 18:17:54 -07:00
David S. Miller f6c5d736af [IPV4]: Remove IPVS icmp hack from route.c for now.
Revert: 2d771cd86d

This is dangerous if enabled and a better solution to the
problem is being worked on.

Signed-off-by: David S. Miller <davem@davemloft.net>
2007-05-18 02:07:50 -07:00
Janusz Krzysztofik 2d771cd86d [IPV4] LVS: Allow to send ICMP unreachable responses when real-servers are removed
this is a small patch by Janusz Krzysztofik to ip_route_output_slow()
that allows VIP-less LVS linux director to generate packets
originating >From VIP if sysctl_ip_nonlocal_bind is set.

In a nutshell, the intention is for an LVS linux director to be able
to send ICMP unreachable responses to end-users when real-servers are
removed.

http://archive.linuxvirtualserver.org/html/lvs-users/2007-01/msg00106.html

Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:28:15 -07:00
Thomas Graf 63f3444fb9 [IPv4]: Use rtnl registration interface
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:27:08 -07:00
Arnaldo Carvalho de Melo eddc9ec53b [SK_BUFF]: Introduce ip_hdr(), remove skb->nh.iph
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:25:10 -07:00
Stephen Hemminger f690808e17 [NET]: make seq_operations const
The seq_file operations stuff can be marked constant to
get it out of dirty cache.

Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:25:03 -07:00
Arnaldo Carvalho de Melo c1d2bbe1cd [SK_BUFF]: Introduce skb_reset_network_header(skb)
For the common, open coded 'skb->nh.raw = skb->data' operation, so that we can
later turn skb->nh.raw into a offset, reducing the size of struct sk_buff in
64bit land while possibly keeping it as a pointer on 32bit.

This one touches just the most simple case, next will handle the slightly more
"complex" cases.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:24:46 -07:00
Arnaldo Carvalho de Melo 98e399f82a [SK_BUFF]: Introduce skb_mac_header()
For the places where we need a pointer to the mac header, it is still legal to
touch skb->mac.raw directly if just adding to, subtracting from or setting it
to another layer header.

This one also converts some more cases to skb_reset_mac_header() that my
regex missed as it had no spaces before nor after '=', ugh.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:24:41 -07:00
Arnaldo Carvalho de Melo 459a98ed88 [SK_BUFF]: Introduce skb_reset_mac_header(skb)
For the common, open coded 'skb->mac.raw = skb->data' operation, so that we can
later turn skb->mac.raw into a offset, reducing the size of struct sk_buff in
64bit land while possibly keeping it as a pointer on 32bit.

This one touches just the most simple case, next will handle the slightly more
"complex" cases.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:24:32 -07:00
James Morris 9d729f72dc [NET]: Convert xtime.tv_sec to get_seconds()
Where appropriate, convert references to xtime.tv_sec to the
get_seconds() helper function.

Signed-off-by: James Morris <jmorris@namei.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:23:32 -07:00
Tim Schmielau cd354f1ae7 [PATCH] remove many unneeded #includes of sched.h
After Al Viro (finally) succeeded in removing the sched.h #include in module.h
recently, it makes sense again to remove other superfluous sched.h includes.
There are quite a lot of files which include it but don't actually need
anything defined in there.  Presumably these includes were once needed for
macros that used to live in sched.h, but moved to other header files in the
course of cleaning it up.

To ease the pain, this time I did not fiddle with any header files and only
removed #includes from .c-files, which tend to cause less trouble.

Compile tested against 2.6.20-rc2 and 2.6.20-rc2-mm2 (with offsets) on alpha,
arm, i386, ia64, mips, powerpc, and x86_64 with allnoconfig, defconfig,
allmodconfig, and allyesconfig as well as a few randconfigs on x86_64 and all
configs in arch/arm/configs on arm.  I also checked that no new warnings were
introduced by the patch (actually, some warnings are removed that were emitted
by unnecessarily included header files).

Signed-off-by: Tim Schmielau <tim@physik3.uni-rostock.de>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-14 08:09:54 -08:00
Arjan van de Ven 9a32144e9d [PATCH] mark struct file_operations const 7
Many struct file_operations in the kernel can be "const".  Marking them const
moves these to the .rodata section, which avoids false sharing with potential
dirty data.  In addition it'll catch accidental writes at compile time to
these shared resources.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-12 09:48:46 -08:00
Eric Dumazet 093c2ca416 [IPV4]: Convert ipv4 route to use the new dst_entry 'next' pointer
This patch removes the rt_next pointer from 'struct rtable.u' union,
and renames u.rt_next to u.dst_rt_next.

It also moves 'struct flowi' right after 'struct dst_entry' to prepare
the gain on lookups.

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-02-10 23:20:38 -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
Patrick McHardy 26932566a4 [NETLINK]: Don't BUG on undersized allocations
Currently netlink users BUG when the allocated skb for an event
notification is undersized. While this is certainly a kernel bug,
its not critical and crashing the kernel is too drastic, especially
when considering that these errors have appeared multiple times in
the past and it BUGs even if no listeners are present.

This patch replaces BUG by WARN_ON and changes the notification
functions to inform potential listeners of undersized allocations
using a unique error code (EMSGSIZE).

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-02-08 12:38:41 -08:00
Li Yewang 14fb8a7647 [IPV4]: Fix BUG of ip_rt_send_redirect()
Fix the redirect packet of the router if the jiffies wraparound.

Signed-off-by: Li Yewang <lyw@nanjing-fnst.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-12-18 00:26:35 -08:00
Alexey Dobriyan 1f29bcd739 [PATCH] sysctl: remove unused "context" param
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Andi Kleen <ak@suse.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: David Howells <dhowells@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-10 09:55:41 -08:00
Patrick McHardy 1b6651f1bf [XFRM]: Use output device disable_xfrm for forwarded packets
Currently the behaviour of disable_xfrm is inconsistent between
locally generated and forwarded packets. For locally generated
packets disable_xfrm disables the policy lookup if it is set on
the output device, for forwarded traffic however it looks at the
input device. This makes it impossible to disable xfrm on all
devices but a dummy device and use normal routing to direct
traffic to that device.

Always use the output device when checking disable_xfrm.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-12-06 18:38:43 -08:00
Thomas Graf e3703b3de1 [RTNETLINK]: Add rtnl_put_cacheinfo() to unify some code
IPv4, IPv6, and DECNet all use struct rta_cacheinfo in a similiar
way, therefore rtnl_put_cacheinfo() is added to reuse code.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-12-02 21:30:44 -08:00
Al Viro 714e85be35 [IPV6]: Assorted trivial endianness annotations.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-12-02 21:22:50 -08:00
Thomas Graf 47dcf0cb10 [NET]: Rethink mark field in struct flowi
Now that all protocols have been made aware of the mark
field it can be moved out of the union thus simplyfing
its usage.

The config options in the IPv4/IPv6/DECnet subsystems
to enable respectively disable mark based routing only
obfuscate the code with ifdefs, the cost for the
additional comparison in the flow key is insignificant,
and most distributions have all these options enabled
by default anyway. Therefore it makes sense to remove
the config options and enable mark based routing by
default.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-12-02 21:21:39 -08:00
Thomas Graf 82e91ffef6 [NET]: Turn nfmark into generic mark
nfmark is being used in various subsystems and has become
the defacto mark field for all kinds of packets. Therefore
it makes sense to rename it to `mark' and remove the
dependency on CONFIG_NETFILTER.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-12-02 21:21:38 -08:00
David S. Miller 8238b218ec [NET]: Do not memcmp() over pad bytes of struct flowi.
They are not necessarily initialized to zero by the compiler,
for example when using run-time initializers of automatic
on-stack variables.

Noticed by Eric Dumazet and Patrick McHardy.

Signed-off-by: David S. Miller <davem@davemloft.net>
2006-10-12 00:49:15 -07:00
Al Viro 17fb2c6439 [IPV4]: RTA_{DST,SRC,GATEWAY,PREFSRC} annotated
these are passed net-endian; use be32 netlink accessors

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-28 17:54:16 -07:00
Al Viro e448515c79 [IPV4] net/ipv4/route.c: trivial endianness annotations
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-28 17:54:15 -07:00
Al Viro d9c9df8c93 [IPV4]: fib_validate_source() annotations
annotated arguments and inferred net-endian variables in callers

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-28 17:54:09 -07:00
Al Viro a61ced5d1c [IPV4]: inet_select_addr() annotations
argument and return value are net-endian.  Annotated function and inferred
net-endian variables in callers.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-28 17:54:08 -07:00
Al Viro 8c7bc84085 [IPV4]: annotate rt_hash_code() users
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-28 17:54:04 -07:00
Al Viro f7655229c0 [IPV4]: ip_rt_redirect() annotations
The first 4 arguments of ip_rt_redirect() are net-endian.  Annotated.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-28 17:54:03 -07:00
Al Viro 9e12bb22e3 [IPV4]: ip_route_input() annotations
ip_route_input() takes net-endian source and destination address.
* Annotated as such.
* arguments of its invocations annotated where needed.
* local helpers getting the same values passed to by it (ip_route_input_mc(),
ip_route_input_slow(), ip_handle_martian_source(), ip_mkroute_input(),
ip_mkroute_input_def(), __mkroute_input()) annotated

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-28 17:54:02 -07:00
Alexey Dobriyan e5d679f339 [NET]: Use SLAB_PANIC
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-22 15:18:19 -07:00
Thomas Graf d889ce3b29 [IPv4]: Convert route get to new netlink api
Fixes various unvalidated netlink attributes causing memory
corruptions when left empty by userspace applications.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-22 14:55:06 -07:00
Thomas Graf be403ea185 [IPv4]: Convert FIB dumping to use new netlink api
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-22 14:55:05 -07:00
Thomas Graf 2942e90050 [RTNETLINK]: Use rtnl_unicast() for rtnetlink unicasts
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-22 14:54:48 -07:00
Patrick McHardy 9e762a4a89 [NET]: Introduce RTA_TABLE/FRA_TABLE attributes
Introduce RTA_TABLE route attribute and FRA_TABLE routing rule attribute
to hold 32 bit routing table IDs. Usespace compatibility is provided by
continuing to accept and send the rtm_table field, but because of its
limited size it can only carry the low 8 bits of the table ID. This
implies that if larger IDs are used, _all_ userspace programs using them
need to use RTA_TABLE.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-22 14:54:25 -07:00
Kirill Korotaev 8d1502de27 [IPV4]: Limit rt cache size properly.
From: Kirill Korotaev <dev@sw.ru>

During OpenVZ stress testing we found that UDP traffic with random src
can generate too much excessive rt hash growing leading finally to OOM
and kernel panics.

It was found that for 4GB i686 system (having 1048576 total pages and
  225280 normal zone pages) kernel allocates the following route hash:
syslog: IP route cache hash table entries: 262144 (order: 8, 1048576
bytes) => ip_rt_max_size = 4194304 entries, i.e.  max rt size is
4194304 * 256b = 1Gb of RAM > normal_zone

Attached the patch which removes HASH_HIGHMEM flag from
alloc_large_system_hash() call.

Signed-off-by: David S. Miller <davem@davemloft.net>
2006-08-07 20:44:22 -07:00
Tom Tucker 8d71740c56 [NET]: Core net changes to generate netevents
Generate netevents for:
- neighbour changes
- routing redirects
- pmtu changes

Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-08-02 13:38:21 -07:00
Ingo Molnar 6205120044 [PATCH] lockdep: fix RT_HASH_LOCK_SZ
On lockdep we have a quite big spinlock_t, so keep the size down.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-03 15:27:05 -07:00
Ingo Molnar 8a25d5debf [PATCH] lockdep: prove spinlock rwlock locking correctness
Use the lock validator framework to prove spinlock and rwlock locking
correctness.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-03 15:27:04 -07:00
Jörn Engel 6ab3d5624e Remove obsolete #include <linux/config.h>
Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-06-30 19:25:36 +02:00
Paul Mackerras bfe5d83419 [PATCH] Define __raw_get_cpu_var and use it
There are several instances of per_cpu(foo, raw_smp_processor_id()), which
is semantically equivalent to __get_cpu_var(foo) but without the warning
that smp_processor_id() can give if CONFIG_DEBUG_PREEMPT is enabled.  For
those architectures with optimized per-cpu implementations, namely ia64,
powerpc, s390, sparc64 and x86_64, per_cpu() turns into more and slower
code than __get_cpu_var(), so it would be preferable to use __get_cpu_var
on those platforms.

This defines a __raw_get_cpu_var(x) macro which turns into per_cpu(x,
raw_smp_processor_id()) on architectures that use the generic per-cpu
implementation, and turns into __get_cpu_var(x) on the architectures that
have an optimized per-cpu implementation.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 10:01:01 -07:00
Stephen Hemminger d2c962b853 [IPV4]: ip_route_input panic fix
This fixes http://bugzilla.kernel.org/show_bug.cgi?id=6388
The bug is caused by ip_route_input dereferencing skb->nh.protocol of
the dummy skb passed dow from inet_rtm_getroute (Thanks Thomas for seeing
it). It only happens if the route requested is for a multicast IP
address.

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-04-17 17:27:11 -07:00
KAMEZAWA Hiroyuki 6f91204225 [PATCH] for_each_possible_cpu: network codes
for_each_cpu() actually iterates across all possible CPUs.  We've had mistakes
in the past where people were using for_each_cpu() where they should have been
iterating across only online or present CPUs.  This is inefficient and
possibly buggy.

We're renaming for_each_cpu() to for_each_possible_cpu() to avoid this in the
future.

This patch replaces for_each_cpu with for_each_possible_cpu under /net

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-04-11 06:18:31 -07:00
Ilia Sotnikov cef2685e00 [IPV4]: Aggregate route entries with different TOS values
When we get an ICMP need-to-frag message, the original TOS value in the
ICMP payload cannot be used as a key to look up the routes to update.
This is because the TOS field may have been modified by routers on the
way.  Similarly, ip_rt_redirect should also ignore the TOS as the router
that gave us the message may have modified the TOS value.

The patch achieves this objective by aggregating entries with different
TOS values (but are otherwise identical) into the same bucket.  This
makes it easy to update them at the same time when an ICMP message is
received.

In future we should use a twin-hashing scheme where teh aggregation
occurs at the entry level.  That is, the TOS goes back into the hash
for normal lookups while ICMP lookups will end up with a node that
gives us a list that contains all other route entries that differ
only by TOS.

Signed-off-by: Ilia Sotnikov <hostcc@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-25 01:38:55 -08:00
Suresh Bhogavilli 8525987849 [IPV4]: Fix garbage collection of multipath route entries
When garbage collecting route cache entries of multipath routes
in rt_garbage_collect(), entries were deleted from the hash bucket
'i' while holding a spin lock on bucket 'k' resulting in a system
hang.  Delete entries, if any, from bucket 'k' instead.

Signed-off-by: Suresh Bhogavilli <sbhogavilli@verisign.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-02-23 16:10:52 -08:00
Andrew Morton dbd2915ce8 [IPV4]: RT_CACHE_STAT_INC() warning fix
BUG: using smp_processor_id() in preemptible [00000001] code: rpc.statd/2408

And it _is_ a bug, but I guess we don't care enough to add preempt_disable().

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-01-17 22:46:49 -08:00
Eric Dumazet 2f970d8357 [IPV4]: rt_cache_stat can be statically defined
Using __get_cpu_var(obj) is slightly faster than per_cpu_ptr(obj, 
raw_smp_processor_id()).

1) Smaller code and memory use
For static and small objects, DEFINE_PER_CPU(type, object) is preferred over a 
alloc_percpu() : Better and smaller code to access them, and no extra memory 
(storing the pointer, and the percpu array of pointers)

x86_64 code before patch

mov    1237577(%rip),%rax        # ffffffff803e5990 <rt_cache_stat>
not    %rax  # part of per_cpu machinery
mov    %gs:0x3c,%edx # get cpu number
movslq %edx,%rdx # extend 32 bits cpu number to 64 bits
mov    (%rax,%rdx,8),%rax # get the pointer for this cpu
incl   0x38(%rax)

x86_64 code after patch

mov    $per_cpu__rt_cache_stat,%rdx
mov    %gs:0x48,%rax # get percpu data offset
incl   0x38(%rax,%rdx,1)

2) False sharing avoidance for SMP :
For a small NR_CPUS, the array of per cpu pointers allocated in alloc_percpu() 
can be <= 32 bytes. This let slab code gives a part of a cache line. If the 
other part of this 64 bytes (or 128 bytes) cache line is used by a mostly 
written object, we can have false sharing and expensive per_cpu_ptr() operations.

Size of rt_cache_stat is 64 bytes, so this patch is not a danger of a too big 
increase of bss (in UP mode) or static per_cpu data for SMP 
(PERCPU_ENOUGH_ROOM is currently 32768 bytes)

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-01-17 02:54:36 -08:00
Arjan van de Ven 9b5b5cff9a [NET]: Add const markers to various variables.
the patch below marks various variables const in net/; the goal is to
move them to the .rodata section so that they can't false-share
cachelines with things that get written to, as well as potentially
helping gcc a bit with optimisations.  (these were found using a gcc
patch to warn about such variables)

Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-11-29 16:21:38 -08:00
Mike Stroyan 18955cfcb2 [IPV4] tcp/route: Another look at hash table sizes
The tcp_ehash hash table gets too big on systems with really big memory.
It is worse on systems with pages larger than 4KB.  It wastes memory that
could be better used.  It also makes the netstat command slow because reading
/proc/net/tcp and /proc/net/tcp6 needs to go through the full hash table.

  The default value should not be larger for larger page sizes.  It seems
that the effect of page size is an unintended error dating back a long
time.  I also wonder if the default value really should be a larger
fraction of memory for systems with more memory.  While systems with
really big ram can afford more space for hash tables, it is not clear to
me that they benefit from increasing the allocation ratio for this table.

  The amount of memory allocated is determined by net/ipv4/tcp.c:tcp_init and
mm/page_alloc.c:alloc_large_system_hash.

tcp_init calls alloc_large_system_hash passing parameters-
    bucketsize=sizeof(struct tcp_ehash_bucket)
    numentries=thash_entries
    scale=(num_physpages >= 128 * 1024) ? (25-PAGE_SHIFT) : (27-PAGE_SHIFT)
    limit=0

On i386, PAGE_SHIFT is 12 for a page size of 4K
On ia64, PAGE_SHIFT defaults to 14 for a page size of 16K

The num_physpages test above makes the allocation take a larger fraction
of the total memory on systems with larger memory.  The threshold size
for a i386 system is 512MB.  For an ia64 system with 16KB pages the
threshold is 2GB.

For smaller memory systems-
On i386, scale = (27 - 12) = 15
On ia64, scale = (27 - 14) = 13
For larger memory systems-
On i386, scale = (25 - 12) = 13
On ia64, scale = (25 - 14) = 11

  For the rest of this discussion, I'll just track the larger memory case.

  The default behavior has numentries=thash_entries=0, so the allocated
size is determined by either scale or by the default limit of 1/16 of
total memory.

In alloc_large_system_hash-
|	numentries = (flags & HASH_HIGHMEM) ? nr_all_pages : nr_kernel_pages;
|	numentries += (1UL << (20 - PAGE_SHIFT)) - 1;
|	numentries >>= 20 - PAGE_SHIFT;
|	numentries <<= 20 - PAGE_SHIFT;

  At this point, numentries is pages for all of memory, rounded up to the
nearest megabyte boundary.

|	/* limit to 1 bucket per 2^scale bytes of low memory */
|	if (scale > PAGE_SHIFT)
|		numentries >>= (scale - PAGE_SHIFT);
|	else
|		numentries <<= (PAGE_SHIFT - scale);

On i386, numentries >>= (13 - 12), so numentries is 1/8196 of
bytes of total memory.
On ia64, numentries <<= (14 - 11), so numentries is 1/2048 of
bytes of total memory.

|        log2qty = long_log2(numentries);
|
|        do {
|                size = bucketsize << log2qty;

bucketsize is 16, so size is 16 times numentries, rounded
down to a power of two.

On i386, size is 1/512 of bytes of total memory.
On ia64, size is 1/128 of bytes of total memory.

For smaller systems the results are
On i386, size is 1/2048 of bytes of total memory.
On ia64, size is 1/512 of bytes of total memory.

  The large page effect can be removed by just replacing
the use of PAGE_SHIFT with a constant of 12 in the calls to
alloc_large_system_hash.  That makes them more like the other uses of
that function from fs/inode.c and fs/dcache.c

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-11-29 16:12:55 -08:00
Herbert Xu e5ed639913 [IPV4]: Replace __in_dev_get with __in_dev_get_rcu/rtnl
The following patch renames __in_dev_get() to __in_dev_get_rtnl() and
introduces __in_dev_get_rcu() to cover the second case.

1) RCU with refcnt should use in_dev_get().
2) RCU without refcnt should use __in_dev_get_rcu().
3) All others must hold RTNL and use __in_dev_get_rtnl().

There is one exception in net/ipv4/route.c which is in fact a pre-existing
race condition.  I've marked it as such so that we remember to fix it.

This patch is based on suggestions and prior work by Suzanne Wood and
Paul McKenney.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-10-03 14:35:55 -07:00
Julian Anastasov ce723d8e04 [IPV4]: Fix refcount damaging in net/ipv4/route.c
One such place that can damage the dst refcnts is route.c with
CONFIG_IP_ROUTE_MULTIPATH_CACHED enabled, i don't see the user's
.config. In this new code i see that rt_intern_hash is called before
dst->refcnt is set to 1, dst is the 2nd arg to rt_intern_hash.

Arg 2 of rt_intern_hash must come with refcnt 1 as it is added to
table or dropped depending on error/add/update. One such example is
ip_mkroute_input where __mkroute_input return rth with refcnt 0 which
is provided to rt_intern_hash. ip_mkroute_output looks like a 2nd such
place. Appending untested patch for comments and review.  The idea is
to put previous reference as we are going to return next result/error.

Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-09-08 13:34:47 -07:00
Arnaldo Carvalho de Melo d8c97a9451 [NET]: Export symbols needed by the current DCCP code
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29 15:49:35 -07:00
Adrian Bunk 0742fd53a3 [IPV4]: possible cleanups
This patch contains the following possible cleanups:
- make needlessly global code static
- #if 0 the following unused global function:
  - xfrm4_state.c: xfrm4_state_fini
- remove the following unneeded EXPORT_SYMBOL's:
  - ip_output.c: ip_finish_output
  - ip_output.c: sysctl_ip_default_ttl
  - fib_frontend.c: ip_dev_find
  - inetpeer.c: inet_peer_idlock
  - ip_options.c: ip_options_compile
  - ip_options.c: ip_options_undo
  - net/core/request_sock.c: sysctl_max_syn_backlog

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-29 15:33:20 -07:00
Olaf Kirch 0b7f22aab4 [IPV4]: Prevent oops when printing martian source
In some cases, we may be generating packets with a source address that
qualifies as martian. This can happen when we're in the middle of setting
up the network, and netfilter decides to reject a packet with an RST.
The IPv4 routing code would try to print a warning and oops, because
locally generated packets do not have a valid skb->mac.raw pointer
at this point.

Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-11 21:01:42 -07:00
Eric Dumazet bb1d23b026 [IPV4]: Bug fix in rt_check_expire()
- rt_check_expire() fixes (an overflow occured if size of the hash
  was >= 65536)

reminder of the bugfix:

The rt_check_expire() has a serious problem on machines with large
route caches, and a standard HZ value of 1000.

With default values, ie ip_rt_gc_interval = 60*HZ = 60000 ;

the loop count :

     for (t = ip_rt_gc_interval << rt_hash_log; t >= 0;


overflows (t is a 31 bit value) as soon rt_hash_log is >= 16  (65536
slots in route cache hash table).

In this case, rt_check_expire() does nothing at all

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-05 15:00:32 -07:00
Eric Dumazet 424c4b70cc [IPV4]: Use the fancy alloc_large_system_hash() function for route hash table
- rt hash table allocated using alloc_large_system_hash() function.

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-05 14:58:19 -07:00
Eric Dumazet 22c047ccbc [NET]: Hashed spinlocks in net/ipv4/route.c
- Locking abstraction
- Spinlocks moved out of rt hash table : Less memory (50%) used by rt 
  hash table. it's a win even on UP.
- Sizing of spinlocks table depends on NR_CPUS

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-07-05 14:55:24 -07:00
Dietmar Eggemann 2c2910a401 [IPV4]: Snmpv2 Mib IP counter ipInAddrErrors support
I followed Thomas' proposal to see every martian destination as a case
where the ipInAddrErrors counter has to be incremented. There are
two advantages by doing so: (1) The relation between the ipInReceive
counter and all the other ipInXXX counters is more accurate in the
case the RTN_UNICAST code check fails and (2) it makes the code in
ip_route_input_slow easier.

Signed-off-by: Dietmar Eggemann <dietmar.eggemann@gmx.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-28 13:06:23 -07:00
Chuck Short 7abaa27c1c [IPV4]: Fix route.c gcc4 warnings
Signed-off by: Chuck Short <zulcss@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-22 22:10:23 -07:00
Jamal Hadi Salim b6544c0b4c [NETLINK]: Correctly set NLM_F_MULTI without checking the pid
This patch rectifies some rtnetlink message builders that derive the
flags from the pid. It is now explicit like the other cases
which get it right. Also fixes half a dozen dumpers which did not
set NLM_F_MULTI at all.

Signed-off-by: Jamal Hadi Salim <hadi@cyberus.ca>
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-18 22:54:12 -07:00
Jesper Juhl 02c30a84e6 [PATCH] update Ross Biro bouncing email address
Ross moved.  Remove the bad email address so people will find the correct
one in ./CREDITS.

Signed-off-by: Jesper Juhl <juhl-lkml@dif.dk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-05 16:36:49 -07:00
Olaf Rempel 5bec0039f4 [NET]: /proc/net/stat/* header cleanup
Signed-off-by: Olaf Rempel <razzor@kopf-tisch.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-04-28 12:16:08 -07:00
Dave Jones 7e3e0360b7 [IPV4]: Incorrect permissions on route flush sysctl
This has been brought up before.. http://lkml.org/lkml/2000/1/21/116
but didnt seem to get resolved.  This morning I got someone
file a bugzilla about it breaking sysctl(8).

Signed-off-by: Dave Jones <davej@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-04-28 12:11:03 -07:00
Stephen Hemminger 9c2b3328f7 [NET]: skbuff: remove old NET_CALLER macro
Here is a revised alternative that uses BUG_ON/WARN_ON
(as suggested by Herbert Xu) to eliminate NET_CALLER.

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-04-19 22:39:42 -07:00
Linus Torvalds 1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00