commit a9b3cd7f (rcu: convert uses of rcu_assign_pointer(x, NULL) to
RCU_INIT_POINTER) did a lot of incorrect changes, since it did a
complete conversion of rcu_assign_pointer(x, y) to RCU_INIT_POINTER(x,
y).

We miss needed barriers, even on x86, when y is not NULL.
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
CC: Stephen Hemminger <shemminger@vyatta.com>
CC: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The reverse path filter module will use fib_lookup.

If CONFIG_IP_MULTIPLE_TABLES is not set, fib_lookup is
only a static inline helper that calls fib_table_lookup,
so export that too.
Signed-off-by: NFlorian Westphal <fw@strlen.de>
Acked-by: NDavid S. Miller <davem@davemloft.net>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

These files are non modular, but need to export symbols using
the macros now living in export.h -- call out the include so
that things won't break when we remove the implicit presence
of module.h from everywhere.
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>

When assigning a NULL value to an RCU protected pointer, no barrier
is needed. The rcu_assign_pointer, used to handle that but will soon
change to not handle the special case.

Convert all rcu_assign_pointer of NULL value.

//smpl
@@ expression P; @@

- rcu_assign_pointer(P, NULL)
+ RCU_INIT_POINTER(P, NULL)

// </smpl>
Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Acked-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Compiler is not smart enough to avoid double BSWAP instructions in
ntohl(inet_make_mask(plen)).

Lets cache this value in struct leaf_info, (fill a hole on 64bit arches)

With route cache disabled, this saves ~2% of cpu in udpflood bench on
x86_64 machine.
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

After discovering that wide use of prefetch on modern CPUs
could be a net loss instead of a win, net drivers which were
relying on the implicit inclusion of prefetch.h via the list
headers showed up in the resulting cleanup fallout.  Give
them an explicit include via the following $0.02 script.

 =========================================
 #!/bin/bash
 MANUAL=""
 for i in `git grep -l 'prefetch(.*)' .` ; do
 	grep -q '<linux/prefetch.h>' $i
 	if [ $? = 0 ] ; then
 		continue
 	fi

 	(	echo '?^#include <linux/?a'
 		echo '#include <linux/prefetch.h>'
 		echo .
 		echo w
 		echo q
 	) | ed -s $i > /dev/null 2>&1
 	if [ $? != 0 ]; then
 		echo $i needs manual fixup
 		MANUAL="$i $MANUAL"
 	fi
 done
 echo ------------------- 8\<----------------------
 echo vi $MANUAL
 =========================================
Signed-off-by: NPaul <paul.gortmaker@windriver.com>
[ Fixed up some incorrect #include placements, and added some
  non-network drivers and the fib_trie.c case    - Linus ]
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The rcu callback __leaf_info_free_rcu() just calls a kfree(),
so we use kfree_rcu() instead of the call_rcu(__leaf_info_free_rcu).
Signed-off-by: NLai Jiangshan <laijs@cn.fujitsu.com>
Acked-by: NDavid S. Miller <davem@davemloft.net>
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: NJosh Triplett <josh@joshtriplett.org>

fib_trie_table() is called during netns creation and
Chromium uses clone(CLONE_NEWNET) to sandbox renderer process.

Don't print anything.
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

fib_select_default() is a complete NOP, and completely pointless
to invoke, when we have no more than 1 default route installed.

And this is far and away the common case.

So remember how many prefixlen==0 routes we have in the routing
table, and elide the call when we have no more than one of those.

This cuts output route creation time by 157 cycles on Niagara2+.

In order to add the new int to fib_table, we have to correct the type
of ->tb_data[] to unsigned long, otherwise the private area will be
unaligned on 64-bit systems.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
Reviewed-by: NEric Dumazet <eric.dumazet@gmail.com>

Fixes generated by 'codespell' and manually reviewed.
Signed-off-by: NLucas De Marchi <lucas.demarchi@profusion.mobi>

Add __rcu annotations and lockdep checks.

Add const qualifiers

node_parent() and node_parent_rcu() can use
rcu_dereference_index_check()
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

	The "ipv4: Inline fib_semantic_match into check_leaf"
change forgets to return the route errors. check_leaf should
return the same results as fib_table_lookup.
Signed-off-by: NJulian Anastasov <ja@ssi.bg>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Move the scope value out of the fib alias entries and into fib_info,
so that we always use the correct scope when recomputing the nexthop
cached source address.
Reported-by: NJulian Anastasov <ja@ssi.bg>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

fib_table_delete forgets to match the routes by prefsrc.
Callers can specify known IP in fc_prefsrc and we should remove
the exact route. This is needed for cases when same local or
broadcast addresses are used in different subnets and the
routes differ only in prefsrc. All callers that do not provide
fc_prefsrc will ignore the route prefsrc as before and will
delete the first occurence. That is how the ip route del default
magic works.

	Current callers are:

- ip_rt_ioctl where rtentry_to_fib_config provides fc_prefsrc only
when the provided device name matches IP label with colon.

- inet_rtm_delroute where RTA_PREFSRC is optional too

- fib_magic which deals with routes when deleting addresses
and where the fc_prefsrc is always set with the primary IP
for the concerned IFA.
Signed-off-by: NJulian Anastasov <ja@ssi.bg>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

To start doing these conversions, we need to add some temporary
flow4_* macros which will eventually go away when all the protocol
code paths are changed to work on AF specific flowi objects.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

I intend to turn struct flowi into a union of AF specific flowi
structs.  There will be a common structure that each variant includes
first, much like struct sock_common.

This is the first step to move in that direction.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This elimiates a lot of pure overhead due to parameter
passing.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

GCC emits all kinds of crazy zero extensions when we go from signed
int, to unsigned short, etc. etc.

This transformation has to be legal because:

1) In tkey_extract_bits() in mask_pfx(), the values are used to
   perform shifts, on which negative values are undefined by C.

2) In fib_table_lookup() we perform comparisons with unsigned
   values, constants, and additions.  None of which should
   encounter negative values.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If we end up including include/linux/node.h (either explicitly
or implicitly) that header has a definition of "structt node"
too.

So rename the one we use in fib_trie to "rt_trie_node" to avoid
the conflict.
Reported-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

fib_hash_init() --> fib_trie_init()
fib_hash_table() --> fib_trie_table()
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Both fib_trie and fib_hash have a local implementation of
fib_table_select_default().  This is completely unnecessary
code duplication.

Since we now remember the fib_table and the head of the fib
alias list of the default route, we can implement one single
generic version of this routine.

Looking at the fib_hash implementation you may get the impression
that it's possible for there to be multiple top-level routes in
the table for the default route.  The truth is, it isn't, the
insert code will only allow one entry to exist in the zero
prefix hash table, because all keys evaluate to zero and all
keys in a hash table must be unique.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This will be used later to implement fib_select_default() in a
completely generic manner, instead of the current situation where the
default route is re-looked up in the TRIE/HASH table and then the
available aliases are analyzed.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We forgot to use __GFP_HIGHMEM in several __vmalloc() calls.

In ceph, add the missing flag.

In fib_trie.c, xfrm_hash.c and request_sock.c, using vzalloc() is
cleaner and allows using HIGHMEM pages as well.
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When we stop a namespace we flush the table and free one, but the
added fn_zone-s (and their hashes if grown) are leaked. Need to free.
Tries releases all its stuff in the flushing code.

Shame on us - this bug exists since the very first make-fib-per-net
patches in 2.6.27 :(
Signed-off-by: NPavel Emelyanov <xemul@openvz.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Perf tools session at NFWS 2010 pointed out a false sharing on struct
fib_alias that can be avoided pretty easily, if we set FA_S_ACCESSED bit
only if needed (ie : not already set)
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The patch below updates broken web addresses in the kernel
Signed-off-by: NJustin P. Mattock <justinmattock@gmail.com>
Cc: Maciej W. Rozycki <macro@linux-mips.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Finn Thain <fthain@telegraphics.com.au>
Cc: Randy Dunlap <rdunlap@xenotime.net>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Dimitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Mike Frysinger <vapier.adi@gmail.com>
Acked-by: NBen Pfaff <blp@cs.stanford.edu>
Acked-by: NHans J. Koch <hjk@linutronix.de>
Reviewed-by: NFinn Thain <fthain@telegraphics.com.au>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

fib_table_lookup() might use fls() to speedup an open coded loop.

Noticed while doing a profile analysis.
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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>

Use rcu_dereference_rtnl() helper

Change hard coded constants in fib_flag_trans()
 7 -> RTN_UNREACHABLE
 8 -> RTN_PROHIBIT
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Hi,
Here is one more of these warnings and a patch below:

Sep  5 23:52:33 del kernel: [46044.244833] ===================================================
Sep  5 23:52:33 del kernel: [46044.269681] [ INFO: suspicious rcu_dereference_check() usage. ]
Sep  5 23:52:33 del kernel: [46044.277000] ---------------------------------------------------
Sep  5 23:52:33 del kernel: [46044.285185] net/ipv4/fib_trie.c:1756 invoked rcu_dereference_check() without protection!
Sep  5 23:52:33 del kernel: [46044.293627]
Sep  5 23:52:33 del kernel: [46044.293632] other info that might help us debug this:
Sep  5 23:52:33 del kernel: [46044.293634]
Sep  5 23:52:33 del kernel: [46044.325333]
Sep  5 23:52:33 del kernel: [46044.325335] rcu_scheduler_active = 1, debug_locks = 0
Sep  5 23:52:33 del kernel: [46044.348013] 1 lock held by pppd/1717:
Sep  5 23:52:33 del kernel: [46044.357548]  #0:  (rtnl_mutex){+.+.+.}, at: [<c125dc1f>] rtnl_lock+0xf/0x20
Sep  5 23:52:33 del kernel: [46044.367647]
Sep  5 23:52:33 del kernel: [46044.367652] stack backtrace:
Sep  5 23:52:33 del kernel: [46044.387429] Pid: 1717, comm: pppd Not tainted 2.6.35.4.4a #3
Sep  5 23:52:33 del kernel: [46044.398764] Call Trace:
Sep  5 23:52:33 del kernel: [46044.409596]  [<c12f9aba>] ? printk+0x18/0x1e
Sep  5 23:52:33 del kernel: [46044.420761]  [<c1053969>] lockdep_rcu_dereference+0xa9/0xb0
Sep  5 23:52:33 del kernel: [46044.432229]  [<c12b7235>] trie_firstleaf+0x65/0x70
Sep  5 23:52:33 del kernel: [46044.443941]  [<c12b74d4>] fib_table_flush+0x14/0x170
Sep  5 23:52:33 del kernel: [46044.455823]  [<c1033e92>] ? local_bh_enable_ip+0x62/0xd0
Sep  5 23:52:33 del kernel: [46044.467995]  [<c12fc39f>] ? _raw_spin_unlock_bh+0x2f/0x40
Sep  5 23:52:33 del kernel: [46044.480404]  [<c12b24d0>] ? fib_sync_down_dev+0x120/0x180
Sep  5 23:52:33 del kernel: [46044.493025]  [<c12b069d>] fib_flush+0x2d/0x60
Sep  5 23:52:33 del kernel: [46044.505796]  [<c12b06f5>] fib_disable_ip+0x25/0x50
Sep  5 23:52:33 del kernel: [46044.518772]  [<c12b10d3>] fib_netdev_event+0x73/0xd0
Sep  5 23:52:33 del kernel: [46044.531918]  [<c1048dfd>] notifier_call_chain+0x2d/0x70
Sep  5 23:52:33 del kernel: [46044.545358]  [<c1048f0a>] raw_notifier_call_chain+0x1a/0x20
Sep  5 23:52:33 del kernel: [46044.559092]  [<c124f687>] call_netdevice_notifiers+0x27/0x60
Sep  5 23:52:33 del kernel: [46044.573037]  [<c124faec>] __dev_notify_flags+0x5c/0x80
Sep  5 23:52:33 del kernel: [46044.586489]  [<c124fb47>] dev_change_flags+0x37/0x60
Sep  5 23:52:33 del kernel: [46044.599394]  [<c12a8a8d>] devinet_ioctl+0x54d/0x630
Sep  5 23:52:33 del kernel: [46044.612277]  [<c12aabb7>] inet_ioctl+0x97/0xc0
Sep  5 23:52:34 del kernel: [46044.625208]  [<c123f6af>] sock_ioctl+0x6f/0x270
Sep  5 23:52:34 del kernel: [46044.638046]  [<c109d2b0>] ? handle_mm_fault+0x420/0x6c0
Sep  5 23:52:34 del kernel: [46044.650968]  [<c123f640>] ? sock_ioctl+0x0/0x270
Sep  5 23:52:34 del kernel: [46044.663865]  [<c10c3188>] vfs_ioctl+0x28/0xa0
Sep  5 23:52:34 del kernel: [46044.676556]  [<c10c38fa>] do_vfs_ioctl+0x6a/0x5c0
Sep  5 23:52:34 del kernel: [46044.688989]  [<c1048676>] ? up_read+0x16/0x30
Sep  5 23:52:34 del kernel: [46044.701411]  [<c1021376>] ? do_page_fault+0x1d6/0x3a0
Sep  5 23:52:34 del kernel: [46044.714223]  [<c10b6588>] ? fget_light+0xf8/0x2f0
Sep  5 23:52:34 del kernel: [46044.726601]  [<c1241f98>] ? sys_socketcall+0x208/0x2c0
Sep  5 23:52:34 del kernel: [46044.739140]  [<c10c3eb3>] sys_ioctl+0x63/0x70
Sep  5 23:52:34 del kernel: [46044.751967]  [<c12fca3d>] syscall_call+0x7/0xb
Sep  5 23:52:34 del kernel: [46044.764734]  [<c12f0000>] ? cookie_v6_check+0x3d0/0x630

-------------->

This patch fixes the warning:
 ===================================================
 [ INFO: suspicious rcu_dereference_check() usage. ]
 ---------------------------------------------------
 net/ipv4/fib_trie.c:1756 invoked rcu_dereference_check() without protection!

 other info that might help us debug this:

 rcu_scheduler_active = 1, debug_locks = 0
 1 lock held by pppd/1717:
  #0:  (rtnl_mutex){+.+.+.}, at: [<c125dc1f>] rtnl_lock+0xf/0x20

 stack backtrace:
 Pid: 1717, comm: pppd Not tainted 2.6.35.4a #3
 Call Trace:
  [<c12f9aba>] ? printk+0x18/0x1e
  [<c1053969>] lockdep_rcu_dereference+0xa9/0xb0
  [<c12b7235>] trie_firstleaf+0x65/0x70
  [<c12b74d4>] fib_table_flush+0x14/0x170
  ...

Allow trie_firstleaf() to be called either under rcu_read_lock()
protection or with RTNL held. The same annotation is added to
node_parent_rcu() to prevent a similar warning a bit later.

Followup of commits 634a4b20 and 4eaa0e3c.
Signed-off-by: NJarek Poplawski <jarkao2@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch removes from net/ (but not any netfilter files)
all the unnecessary return; statements that precede the
last closing brace of void functions.

It does not remove the returns that are immediately
preceded by a label as gcc doesn't like that.

Done via:
$ grep -rP --include=*.[ch] -l "return;\n}" net/ | \
  xargs perl -i -e 'local $/ ; while (<>) { s/\n[ \t\n]+return;\n}/\n}/g; print; }'
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Followup of commit 634a4b20

Allow tnode_get_child_rcu() to be called either under rcu_read_lock()
protection or with RTNL held.
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: NTejun Heo <tj@kernel.org>
Guess-its-ok-by: NChristoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>

Allow fib_find_node() to be called either under rcu_read_lock()
protection or with RTNL held.
Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The FIB algorithim for IPV4 is set at compile time, but kernel goes through
the overhead of function call indirection at runtime. Save some
cycles by turning the indirect calls to direct calls to either
hash or trie code.
Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Here is rework and cleanup of the resize function.

Some bugs we had. We were using ->parent when we should use 
node_parent(). Also we used ->parent which is not assigned by
inflate in inflate loop.

Also a fix to set thresholds to power 2 to fit halve 
and double strategy.

max_resize is renamed to max_work which better indicates
it's function.

Reaching max_work is not an error, so warning is removed. 
max_work only limits amount of work done per resize.
(limits CPU-usage, outstanding memory etc).

The clean-up makes it relatively easy to add fixed sized 
root-nodes if we would like to decrease the memory pressure
on routers with large routing tables and dynamic routing.
If we'll need that...

Its been tested with 280k routes.

Work done together with Robert Olsson.
Signed-off-by: NJens Låås <jens.laas@its.uu.se>
Signed-off-by: NRobert Olsson <robert.olsson@its.uu.se>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

String literals are constant, and usually, we can also tag the array
of pointers const too, moving it to the .rodata section.
Signed-off-by: NJan Engelhardt <jengelh@medozas.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

While looking for other fib_trie problems reported by Pawel Staszewski
I noticed there are a few uses of tnode_get_child() and node_parent()
in lookups instead of their rcu versions.
Signed-off-by: NJarek Poplawski <jarkao2@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

During large updates there could be triggered warnings like: "Fix
inflate_threshold_root. Now=25 size=11 bits" if inflate() of the root
node isn't finished in 10 loops. It should be much rarer now, after
changing the threshold from 15 to 25, and a temporary problem, so
this patch tries to handle it automatically using a fix variable to
increase by one inflate threshold for next root resizes (up to the 35
limit, max fix = 10). The fix variable is decreased when root's
inflate() finishes below 7 loops (even if some other, smaller table/
trie is updated -- for simplicity the fix variable is global for now).
Reported-by: NPawel Staszewski <pstaszewski@itcare.pl>
Reported-by: NJorge Boncompte [DTI2] <jorge@dti2.net>
Tested-by: NPawel Staszewski <pstaszewski@itcare.pl>
Signed-off-by: NJarek Poplawski <jarkao2@gmail.com>
Signed-off-by: NRobert Olsson <robert.olsson@its.uu.se>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>