Only used in one place.
Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The function rtnl_kill_links is defined but never used.
Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Function only defined and used in one file.
Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

A couple of functions in socket.c are only used there and
should be localized.
Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Now that vlan acceleration is handled consistently regardless of usage,
it is possible to enable and disable it at will.  This adds support for
Ethtool operations that change the offloading status for debugging
purposes, similar to other forms of hardware acceleration.
Signed-off-by: NJesse Gross <jesse@nicira.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Currently each driver that is capable of vlan hardware acceleration
must be aware of the vlan groups that are configured and then pass
the stripped tag to a specialized receive function.  This is

different from other types of hardware offload in that it places a
significant amount of knowledge in the driver itself rather keeping
it in the networking core.

This makes vlan offloading function more similarly to other forms
of offloading (such as checksum offloading or TSO) by doing the
following:
* On receive, stripped vlans are passed directly to the network
core, without attempting to check for vlan groups or reconstructing
the header if no group
* vlans are made less special by folding the logic into the main
receive routines
* On transmit, the device layer will add the vlan header in software
if the hardware doesn't support it, instead of spreading that logic
out in upper layers, such as bonding.

There are a number of advantages to this:
* Fixes all bugs with drivers incorrectly dropping vlan headers at once.
* Avoids having to disable VLAN acceleration when in promiscuous mode
(good for bridging since it always puts devices in promiscuous mode).
* Keeps VLAN tag separate until given to ultimate consumer, which
avoids needing to do header reconstruction as in tg3 unless absolutely
necessary.
* Consolidates common code in core networking.
Signed-off-by: NJesse Gross <jesse@nicira.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

A struct net_device always maps to zero or one vlan groups and we
always know the device when we are looking up a group.  We currently
do a hash table lookup on the device to find the group but it is
much simpler to just store a pointer.
Signed-off-by: NJesse Gross <jesse@nicira.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Currently users of hardware vlan accleration need to know whether
the device supports it before generating packets.  However, vlan
acceleration will soon be available in a more flexible manner so
knowing ahead of time becomes much more difficult.  This adds
a software fallback path for vlan packets on devices without the
necessary offloading support, similar to other types of hardware
accleration.
Signed-off-by: NJesse Gross <jesse@nicira.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

VLAN_GROUP_ARRAY_LEN is simply the number of possible vlan VIDs.
Since vlan groups will soon be more of an implementation detail
for vlan devices, rename the constant to be descriptive of its
actual purpose.
Signed-off-by: NJesse Gross <jesse@nicira.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There is no point using RCU for dst we allocate for a very short time
(used once).

Change dst_release() to take DST_NOCACHE into account, but also change
skb_dst_set_noref() to force a refcount increment for such dst.

This is a _huge_ gain, because we dont waste memory to store xx thousand
of dsts. Instead of queueing them to RCU, we can free them instantly.

CPU caches can stay hot, re-using same memory blocks to hold temporary
dsts.

Note : remove unneeded smp_mb__before_atomic_dec(); in dst_release(),
since atomic_dec_return() implies a full memory barrier.

Stress test, 160.000.000 udp frames sent, IP route cache disabled
(DDOS).

Before:

real    0m38.091s
user    0m13.189s
sys     7m53.018s

After:

real	0m29.946s
user	0m12.157s
sys	7m40.605s

For reference, if IP route cache was enabled :

real	0m32.030s
user	0m10.521s
sys	8m15.243s
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch introduces netif_alloc_netdev_queues which is called from
register_device instead of alloc_netdev_mq.  This makes TX queue
allocation symmetric with RX allocation.  Also, queue locks allocation
is done in netdev_init_one_queue.  Change set_real_num_tx_queues to
fail if requested number < 1 or greater than number of allocated
queues.
Signed-off-by: NTom Herbert <therbert@google.com>
Acked-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The bonding driver currently modifies the netpoll structure in its xmit path
while sending frames from netpoll.  This is racy, as other cpus can access the
netpoll structure in parallel. Since the bonding driver points np->dev to a
slave device, other cpus can inadvertently attempt to send data directly to
slave devices, leading to improper locking with the bonding master, lost frames,
and deadlocks.  This patch fixes that up.

This patch also removes the real_dev pointer from the netpoll structure as that
data is really only used by bonding in the poll_controller, and we can emulate
its behavior by check each slave for IS_UP.
Signed-off-by: NNeil Horman <nhorman@tuxdriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Since commit e446630c, i.e. v2.6.35-rc1,
the mcp251x chip model can be selected via the modalias member in the
struct spi_board_info. The driver stores the actual model in the
struct mcp251x_platform_data.

From the driver point of view the platform_data should be read only.
Since all in-tree users of the mcp251x have already been converted to
the modalias method, this patch moves the "model" member from the
struct mcp251x_platform_data to the driver's private data structure.
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>
Cc: Christian Pellegrin <chripell@fsfe.org>
Cc: Marc Zyngier <maz@misterjones.org>

In a network bench, I noticed an unfortunate false sharing between
'loopback_dev' and 'count' fields in "struct net".

'count' is written each time a socket is created or destroyed, while
loopback_dev might be often read in routing code.

Move loopback_dev in a read mostly section of "struct net"

Note: struct netns_xfrm is cache line aligned on SMP.
(It contains a "struct dst_ops")
Move it at the end to avoid holes, and reduce sizeof(struct net) by 128
bytes on ia32.
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Do some cleanups of TIPC based on make namespacecheck
  1. Don't export unused symbols
  2. Eliminate dead code
  3. Make functions and variables local
  4. Rename buf_acquire to tipc_buf_acquire since it is used in several files

Compile tested only.
This make break out of tree kernel modules that depend on TIPC routines.
Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Acked-by: NJon Maloy <jon.maloy@ericsson.com>
Acked-by: NPaul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

commit b30973f8 (node-aware skb allocation) spread a wrong habit of
allocating net drivers skbs on a given memory node : The one closest to
the NIC hardware. This is wrong because as soon as we try to scale
network stack, we need to use many cpus to handle traffic and hit
slub/slab management on cross-node allocations/frees when these cpus
have to alloc/free skbs bound to a central node.

skb allocated in RX path are ephemeral, they have a very short
lifetime : Extra cost to maintain NUMA affinity is too expensive. What
appeared as a nice idea four years ago is in fact a bad one.

In 2010, NIC hardwares are multiqueue, or we use RPS to spread the load,
and two 10Gb NIC might deliver more than 28 million packets per second,
needing all the available cpus.

Cost of cross-node handling in network and vm stacks outperforms the
small benefit hardware had when doing its DMA transfert in its 'local'
memory node at RX time. Even trying to differentiate the two allocations
done for one skb (the sk_buff on local node, the data part on NIC
hardware node) is not enough to bring good performance.
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Acked-by: NTom Herbert <therbert@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Based on suggestion by Rémi Denis-Courmont to implement 'connect'
for Pipe controller logic,  this patch implements 'connect' socket
call for the Pipe controller logic.
The patch does following:-
- Removes setsockopts for PNPIPE_CREATE and PNPIPE_DESTROY
- Adds setsockopt for setting the Pipe handle value
- Implements connect socket call
- Updates the Pipe controller logic

User-space should now follow below sequence with Pipe controller:-
-socket
-bind
-setsockopt for PNPIPE_PIPE_HANDLE
-connect
-setsockopt for PNPIPE_ENCAP_IP
-setsockopt for PNPIPE_ENABLE

GPRS/3G data has been tested working fine with this.
Signed-off-by: NKumar Sanghvi <kumar.sanghvi@stericsson.com>
Acked-by: NRémi Denis-Courmont <remi.denis-courmont@nokia.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Using the frame registration notification, we
can see when probe requests are requested and
notify the low-level driver via filtering. The
flag is also set in AP and IBSS modes.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Drivers may need to adjust their filters according
to frame registrations, so notify them about them.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

wext: fix alignment problem in serializing 'struct iw_point'

This fixes a typo in the definition of the serialized length of struct iw_point:
 a) wireless.h is exported to userspace, the typo causes IW_EV_POINT_PK_LEN
    to be 12 on 64-bit, and 8 on 32-bit systems (causing misalignment);
 b) in compat-64 mode iwe_stream_add_point() memcpys overlap (see below).

The second case in  in compat-64 mode looks like (variable names are as in
include/net/iw_handler.h:iwe_stream_add_point()):

 point_len = IW_EV_COMPAT_POINT_LEN = 8
 lcp_len   = IW_EV_COMPAT_LCP_LEN   = 4
 2nd memcpy: IW_EV_POINT_PK_LEN - IW_EV_LCP_PK_LEN = 12 - 4 = 8

 IW_EV_LCP_PK_LEN
 <-------------->                *---> 'extra' data area
 +-------+-------+-------+-------+---------------+------- ...-+
 | len   | cmd   |length | flags |  (empty) -> extra      ... |
 +-------+-------+-------+-------+---------------+------- ...-+
    2       2       2       2          4

     lcp_len
 <-------------->                <-!! OVERLAP !!>
 <--1st memcpy--><------- 2nd memcpy ----------->
                                 <---- 3rd memcpy ------- ... >
 <--------- point_len ---------->

This case could cause overrun whenever iw_point.length < 4.
The other two cases are -
 * 32-bit systems: IW_EV_POINT_PK_LEN - IW_EV_LCP_PK_LEN =  8 - 4 = 4,
   the second memcpy copies exactly the 4 required bytes;
 * 64-bit systems: IW_EV_POINT_PK_LEN - IW_EV_LCP_PK_LEN = 12 - 4 = 8,
   the second memcpy copies a superfluous (but non overlapping) 4 bytes.

The patch changes IW_EV_POINT_PK_LEN to be 8, so that in all 3 cases always only
the requested iw_point.{length,flags} (both __u16) are copied, avoiding overrrun
(compat-64) and superfluous copy (64-bit). In addition, the userspace header is
sanitized (in agreement with version 30 of the wireless tools).

Many thanks to Johannes Berg for help and review with this patch.
Signed-off-by: NGerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

We tried very hard to remove all possible dev_hold()/dev_put() pairs in
network stack, using RCU conversions.

There is still an unavoidable device refcount change for every dst we
create/destroy, and this can slow down some workloads (routers or some
app servers, mmap af_packet)

We can switch to a percpu refcount implementation, now dynamic per_cpu
infrastructure is mature. On a 64 cpus machine, this consumes 256 bytes
per device.

On x86, dev_hold(dev) code :

before
        lock    incl 0x280(%ebx)
after:
        movl    0x260(%ebx),%eax
        incl    fs:(%eax)

Stress bench :

(Sending 160.000.000 UDP frames,
IP route cache disabled, dual E5540 @2.53GHz,
32bit kernel, FIB_TRIE)

Before:

real    1m1.662s
user    0m14.373s
sys     12m55.960s

After:

real    0m51.179s
user    0m15.329s
sys     10m15.942s
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Remove dead code and unused rfcomm thread events
Signed-off-by: NAndrei Emeltchenko <andrei.emeltchenko@nokia.com>
Acked-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NGustavo F. Padovan <padovan@profusion.mobi>

This commit adds a bt_sock_stream_recvmsg() function for use by any
Bluetooth code that uses SOCK_STREAM sockets.  This code is copied
from rfcomm_sock_recvmsg() with minimal modifications to remove
RFCOMM-specific functionality and improve readability.

L2CAP (with the SOCK_STREAM socket type) and RFCOMM have common needs
when it comes to reading data.  Proper stream read semantics require
that applications can read from a stream one byte at a time and not
lose any data.  The RFCOMM code already operated on and pulled data
from the underlying L2CAP socket, so very few changes were required to
make the code more generic for use with non-RFCOMM data over L2CAP.

Applications that need more awareness of L2CAP frame boundaries are
still free to use SOCK_SEQPACKET sockets, and may verify that they
connection did not fall back to basic mode by calling getsockopt().
Signed-off-by: NMat Martineau <mathewm@codeaurora.org>
Acked-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NGustavo F. Padovan <padovan@profusion.mobi>

Signed-off-by: NDavid Vrabel <david.vrabel@csr.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NGustavo F. Padovan <padovan@profusion.mobi>

HCI transport drivers may not know what type of radio an AMP device has
so only say whether they're BR/EDR or AMP devices.
Signed-off-by: NDavid Vrabel <david.vrabel@csr.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NGustavo F. Padovan <padovan@profusion.mobi>

Le mardi 12 octobre 2010 à 00:02 +0200, Eric Dumazet a écrit :
> Here is the followup patch.
>
> Thanks !
>

Oops, this was an old version, the up2date ones also took care of "used"
field.

I guess its time for a sleep, sorry again.

[PATCH net-next V2] neigh: reorder struct neighbour fields

(refcnt) and (ha_lock, ha, used, dev, output, ops, primary_key) should
be placed on a separate cache lines.

refcnt can be often written, while other fields are mostly read.

This gave me good result on stress test :

before:

real    0m45.570s
user    0m15.525s
sys     9m56.669s

After:

real    0m41.841s
user    0m15.261s
sys     8m45.949s
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

struct dst_ops tracks number of allocated dst in an atomic_t field,
subject to high cache line contention in stress workload.

Switch to a percpu_counter, to reduce number of time we need to dirty a
central location. Place it on a separate cache line to avoid dirtying
read only fields.

Stress test :

(Sending 160.000.000 UDP frames,
IP route cache disabled, dual E5540 @2.53GHz,
32bit kernel, FIB_TRIE, SLUB/NUMA)

Before:

real    0m51.179s
user    0m15.329s
sys     10m15.942s

After:

real	0m45.570s
user	0m15.525s
sys	9m56.669s

With a small reordering of struct neighbour fields, subject of a
following patch, (to separate refcnt from other read mostly fields)

real	0m41.841s
user	0m15.261s
sys	8m45.949s
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add a seqlock in struct neighbour to protect neigh->ha[], and avoid
dirtying neighbour in stress situation (many different flows / dsts)

Dirtying takes place because of read_lock(&n->lock) and n->used writes.

Switching to a seqlock, and writing n->used only on jiffies changes
permits less dirtying.
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch updates IEEE802.11 mesh constants to be consistent with newly
approved values. It modifies some values, as well as adds many new constants
in preparation for updating mesh code to the current 802.11s drafts. ANA
numbers were taken from:
https://mentor.ieee.org/802.11/dcn/09/11-09-0031-12-0000-ana-database-assigned-number-authority.xls

A few notes are in order:
1. This will break backwards compatibility with existing Linux kernels as
over-the-air constants have changed.
2. Some old and obsolete constants have been retained for now as the mesh code
itself hasn't been updated yet to the new 802.11s draft. This was desired to
keep the existing mesh scheme working until it can be updated. Adding the
approved values is the first step in updating the mesh code.
3. Obsolete constants have been clearly marked.
4. All ANA approved 802.11s constants have been added.
Signed-off-by: NSteve deRosier <steve@cozybit.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Using these, user space can calculate a relative channel utilization
with arbitrary intervals by regularly taking snapshots of the survey
results.
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Some stats for /proc/net/wireless (and wext in general) are not
being set.  This patch addresses a few of those with values easily
obtained from mac80211 core.
Signed-off-by: NBen Greear <greearb@candelatech.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

When a new dst is used to send a frame, neigh_resolve_output() tries to
associate an struct hh_cache to this dst, calling neigh_hh_init() with
the neigh rwlock write locked.

Most of the time, hh_cache is already known and linked into neighbour,
so we find it and increment its refcount.

This patch changes the logic so that we call neigh_hh_init() with
neighbour lock read locked only, so that fast path can be run in
parallel by concurrent cpus.

This brings part of the speedup we got with commit c7d4426a
(introduce DST_NOCACHE flag) for non cached dsts, even for cached ones,
removing one of the contention point that routers hit on multiqueue
enabled machines.

Further improvements would need to use a seqlock instead of an rwlock to
protect neigh->ha[], to not dirty neigh too often and remove two atomic
ops.
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The current code works like this:

  int garbage, status;
  socklen_t len = sizeof(status);

  /* enable pipe */
  setsockopt(fd, SOL_PNPIPE, PNPIPE_ENABLE, &garbage, sizeof(garbage));
  /* disable pipe */
  setsockopt(fd, SOL_PNPIPE, PNPIPE_DISABLE, &garbage, sizeof(garbage));
  /* get status */
  getsockopt(fd, SOL_PNPIPE, PNPIPE_INQ, &status, &len);

...which does not follow the usual socket option pattern. This patch
merges all three "options" into a single gettable&settable option,
before Linux 2.6.37 gets out:

  int status;
  socklen_t len = sizeof(status);

  /* enable pipe */
  status = 1;
  setsockopt(fd, SOL_PNPIPE, PNPIPE_ENABLE, &status, sizeof(status));
  /* disable pipe */
  status = 0;
  setsockopt(fd, SOL_PNPIPE, PNPIPE_ENABLE, &status, sizeof(status));
  /* get status */
  getsockopt(fd, SOL_PNPIPE, PNPIPE_ENABLE, &status, &len);

This also fixes the error code from EFAULT to ENOTCONN.
Signed-off-by: NRémi Denis-Courmont <remi.denis-courmont@nokia.com>
Cc: Kumar Sanghvi <kumar.sanghvi@stericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There's no need for the WDS peer address
to not be const, so make it const.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

This is the second step for neighbour RCU conversion.

(first was commit d6bf7817 : RCU conversion of neigh hash table)

neigh_lookup() becomes lockless, but still take a reference on found
neighbour. (no more read_lock()/read_unlock() on tbl->lock)

struct neighbour gets an additional rcu_head field and is freed after an
RCU grace period.

Future work would need to eventually not take a reference on neighbour
for temporary dst (DST_NOCACHE), but this would need dst->_neighbour to
use a noref bit like we did for skb->_dst.
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This information is already available in mac80211, we just need to export it
via cfg80211 and nl80211.
Signed-off-by: NBruno Randolf <br1@einfach.org>
Acked-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

This adds API to allow adding per-station GTKs,
updates mac80211 to support it, and also allows
drivers to remove a key from hwaccel again when
this may be necessary due to multiple GTKs.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

fib_lookup() converted to be called in RCU protected context, no
reference taken and released on a contended cache line (fib_clntref)

fib_table_lookup() and fib_semantic_match() get an additional parameter.

struct fib_info gets an rcu_head field, and is freed after an rcu grace
period.

Stress test :
(Sending 160.000.000 UDP frames on same neighbour,
IP route cache disabled, dual E5540 @2.53GHz,
32bit kernel, FIB_HASH) (about same results for FIB_TRIE)

Before patch :

real	1m31.199s
user	0m13.761s
sys	23m24.780s

After patch:

real	1m5.375s
user	0m14.997s
sys	15m50.115s

Before patch Profile :

13044.00 15.4% __ip_route_output_key vmlinux
 8438.00 10.0% dst_destroy           vmlinux
 5983.00  7.1% fib_semantic_match    vmlinux
 5410.00  6.4% fib_rules_lookup      vmlinux
 4803.00  5.7% neigh_lookup          vmlinux
 4420.00  5.2% _raw_spin_lock        vmlinux
 3883.00  4.6% rt_set_nexthop        vmlinux
 3261.00  3.9% _raw_read_lock        vmlinux
 2794.00  3.3% fib_table_lookup      vmlinux
 2374.00  2.8% neigh_resolve_output  vmlinux
 2153.00  2.5% dst_alloc             vmlinux
 1502.00  1.8% _raw_read_lock_bh     vmlinux
 1484.00  1.8% kmem_cache_alloc      vmlinux
 1407.00  1.7% eth_header            vmlinux
 1406.00  1.7% ipv4_dst_destroy      vmlinux
 1298.00  1.5% __copy_from_user_ll   vmlinux
 1174.00  1.4% dev_queue_xmit        vmlinux
 1000.00  1.2% ip_output             vmlinux

After patch Profile :

13712.00 15.8% dst_destroy             vmlinux
 8548.00  9.9% __ip_route_output_key   vmlinux
 7017.00  8.1% neigh_lookup            vmlinux
 4554.00  5.3% fib_semantic_match      vmlinux
 4067.00  4.7% _raw_read_lock          vmlinux
 3491.00  4.0% dst_alloc               vmlinux
 3186.00  3.7% neigh_resolve_output    vmlinux
 3103.00  3.6% fib_table_lookup        vmlinux
 2098.00  2.4% _raw_read_lock_bh       vmlinux
 2081.00  2.4% kmem_cache_alloc        vmlinux
 2013.00  2.3% _raw_spin_lock          vmlinux
 1763.00  2.0% __copy_from_user_ll     vmlinux
 1763.00  2.0% ip_output               vmlinux
 1761.00  2.0% ipv4_dst_destroy        vmlinux
 1631.00  1.9% eth_header              vmlinux
 1440.00  1.7% _raw_read_unlock_bh     vmlinux

Reference results, if IP route cache is enabled :

real	0m29.718s
user	0m10.845s
sys	7m37.341s

25213.00 29.5% __ip_route_output_key   vmlinux
 9011.00 10.5% dst_release             vmlinux
 4817.00  5.6% ip_push_pending_frames  vmlinux
 4232.00  5.0% ip_finish_output        vmlinux
 3940.00  4.6% udp_sendmsg             vmlinux
 3730.00  4.4% __copy_from_user_ll     vmlinux
 3716.00  4.4% ip_route_output_flow    vmlinux
 2451.00  2.9% __xfrm_lookup           vmlinux
 2221.00  2.6% ip_append_data          vmlinux
 1718.00  2.0% _raw_spin_lock_bh       vmlinux
 1655.00  1.9% __alloc_skb             vmlinux
 1572.00  1.8% sock_wfree              vmlinux
 1345.00  1.6% kfree                   vmlinux
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Allow sysadmins to configure the number of multicast
membership report sent on a link failure event.
Signed-off-by: NFlavio Leitner <fleitner@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

David

This is the first step for RCU conversion of neigh code.

Next patches will convert hash_buckets[] and "struct neighbour" to RCU
protected objects.

Thanks

[PATCH net-next] net neigh: RCU conversion of neigh hash table

Instead of storing hash_buckets, hash_mask and hash_rnd in "struct
neigh_table", a new structure is defined :

struct neigh_hash_table {
       struct neighbour        **hash_buckets;
       unsigned int            hash_mask;
       __u32                   hash_rnd;
       struct rcu_head         rcu;
};

And "struct neigh_table" has an RCU protected pointer to such a
neigh_hash_table.

This means the signature of (*hash)() function changed: We need to add a
third parameter with the actual hash_rnd value, since this is not
anymore a neigh_table field.
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>