This patch addresses two issues.

The first issue is the fact that I believe I had the RCU freeing sequence
slightly out of order.  As a result we could get into an issue if a caller
went into a child of a child of the new node, then backtraced into the to be
freed parent, and then attempted to access a child of a child that may have
been consumed in a resize of one of the new nodes children.  To resolve this I
have moved the resize after we have freed the oldtnode.  The only side effect
of this is that we will now be calling resize on more nodes in the case of
inflate due to the fact that we don't have a good way to test to see if a
full_tnode on the new node was there before or after the allocation.  This
should have minimal impact however since the node should already be
correctly size so it is just the cost of calling should_inflate that we
will be taking on the node which is only a couple of cycles.

The second issue is the fact that inflate and halve were essentially doing
the same thing after the new node was added to the trie replacing the old
one.  As such it wasn't really necessary to keep the code in both functions
so I have split it out into two other functions, called replace and
update_children.
Signed-off-by: NAlexander Duyck <alexander.h.duyck@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In doing performance testing and analysis of the changes I recently found
that by shifting the index I had created an unnecessary dependency.

I have updated the code so that we instead shift a mask by bits and then
just test against that as that should save us about 2 CPU cycles since we
can generate the mask while the key and pos are being processed.
Signed-off-by: NAlexander Duyck <alexander.h.duyck@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This change adds a tracking value for the maximum suffix length of all
prefixes stored in any given tnode.  With this value we can determine if we
need to backtrace or not based on if the suffix is greater than the pos
value.

By doing this we can reduce the CPU overhead for lookups in the local table
as many of the prefixes there are 32b long and have a suffix length of 0
meaning we can immediately backtrace to the root node without needing to
test any of the nodes between it and where we ended up.
Signed-off-by: NAlexander Duyck <alexander.h.duyck@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

For some reason the compiler doesn't seem to understand that when we are in
a loop that runs from tnode_child_length - 1 to 0 we don't expect the value
of tn->bits to change.  As such every call to tnode_get_child was rerunning
tnode_chile_length which ended up consuming quite a bit of space in the
resultant assembly code.

I have gone though and verified that in all cases where tnode_get_child
is used we are either winding though a fixed loop from tnode_child_length -
1 to 0, or are in a fastpath case where we are verifying the value by
either checking for any remaining bits after shifting index by bits and
testing for leaf, or by using tnode_child_length.

size net/ipv4/fib_trie.o
Before:
   text	   data	    bss	    dec	    hex	filename
  15506	    376	      8	  15890	   3e12	net/ipv4/fib_trie.o

After:
   text	   data	    bss	    dec	    hex	filename
  14827	    376	      8	  15211	   3b6b	net/ipv4/fib_trie.o
Signed-off-by: NAlexander Duyck <alexander.h.duyck@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This change pulls the node_set_parent functionality out of put_child_reorg
and instead leaves that to the function to take care of as well.  By doing
this we can fully construct the new cluster of tnodes and all of the
pointers out of it before we start routing pointers into it.

I am suspecting this will likely fix some concurency issues though I don't
have a good test to show as such.
Signed-off-by: NAlexander Duyck <alexander.h.duyck@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This change pushes the tnode freeing down into the inflate and halve
functions.  It makes more sense here as we have a better grasp of what is
going on and when a given cluster of nodes is ready to be freed.

I believe this may address a bug in the freeing logic as well.  For some
reason if the freelist got to a certain size we would call
synchronize_rcu().  I'm assuming that what they meant to do is call
synchronize_rcu() after they had handed off that much memory via
call_rcu().  As such that is what I have updated the behavior to be.
Signed-off-by: NAlexander Duyck <alexander.h.duyck@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This change makes it so that the assignment of the tnode to the parent is
handled directly within whatever function is currently handling the node be
it inflate, halve, or resize.  By doing this we can avoid some of the need
to set NULL pointers in the tree while we are resizing the subnodes.
Signed-off-by: NAlexander Duyck <alexander.h.duyck@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This change pulls the logic for if we should inflate/halve the nodes out
into separate functions.  It also addresses what I believe is a bug where 1
full node is all that is needed to keep a node from ever being halved.

Simple script to reproduce the issue:
	modprobe dummy;	ifconfig dummy0 up
	for i in `seq 0 255`; do ifconfig dummy0:$i 10.0.${i}.1/24 up; done
	ifconfig dummy0:256 10.0.255.33/16 up
	for i in `seq 0 254`; do ifconfig dummy0:$i down; done

Results from /proc/net/fib_triestat
Before:
	Local:
		Aver depth:     3.00
		Max depth:      4
		Leaves:         17
		Prefixes:       18
		Internal nodes: 11
		  1: 8  2: 2  10: 1
		Pointers: 1048
	Null ptrs: 1021
	Total size: 11  kB
After:
	Local:
		Aver depth:     3.41
		Max depth:      5
		Leaves:         17
		Prefixes:       18
		Internal nodes: 12
		  1: 8  2: 3  3: 1
		Pointers: 36
	Null ptrs: 8
	Total size: 3  kB
Signed-off-by: NAlexander Duyck <alexander.h.duyck@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This change consists of a cut/paste of resize to behind inflate and halve
so that I could remove the two function prototypes.
Signed-off-by: NAlexander Duyck <alexander.h.duyck@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This change is to start cleaning up some of the rcu_read_lock/unlock
handling.  I realized while reviewing the code there are several spots that
I don't believe are being handled correctly or are masking warnings by
locally calling rcu_read_lock/unlock instead of calling them at the correct
level.

A common example is a call to fib_get_table followed by fib_table_lookup.
The rcu_read_lock/unlock ought to wrap both but there are several spots where
they were not wrapped.
Signed-off-by: NAlexander Duyck <alexander.h.duyck@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This change makes it so that anything that can be shifted by, or compared
to a value shifted by bits is updated to be an unsigned long.  This is
mostly a precaution against an insanely huge address space that somehow
starts coming close to the 2^32 root node size which would require
something like 1.5 billion addresses.

I chose unsigned long instead of unsigned long long since I do not believe
it is possible to allocate a 32 bit tnode on a 32 bit system as the memory
consumed would be 16GB + 28B which exceeds the addressible space for any
one process.
Signed-off-by: NAlexander Duyck <alexander.h.duyck@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This change moves the pos value to the other side of the "bits" field.  By
doing this it actually simplifies a significant amount of code in the trie.

For example when halving a tree we know that the bit lost exists at
oldnode->pos, and if we inflate the tree the new bit being add is at
tn->pos.  Previously to find those bits you would have to subtract pos and
bits from the keylength or start with a value of (1 << 31) and then shift
that.

There are a number of spots throughout the code that benefit from this.  In
the case of the hot-path searches the main advantage is that we can drop 2
or more operations from the search path as we no longer need to compute the
value for the index to be shifted by and can instead just use the raw pos
value.

In addition the tkey_extract_bits is now defunct and can be replaced by
get_index since the two operations were doing the same thing, but now
get_index does it much more quickly as it is only an xor and shift versus a
pair of shifts and a subtraction.
Signed-off-by: NAlexander Duyck <alexander.h.duyck@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch updates the fib_table_insert function to take advantage of the
changes made to improve the performance of fib_table_lookup.  As a result
the code should be smaller and run faster then the original.
Signed-off-by: NAlexander Duyck <alexander.h.duyck@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch makes use of the same features I made use of for
fib_table_lookup to streamline fib_find_node.  The resultant code should be
smaller and run faster than the original.
Signed-off-by: NAlexander Duyck <alexander.h.duyck@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch is meant to reduce the complexity of fib_table_lookup by reducing
the number of variables to the bare minimum while still keeping the same if
not improved functionality versus the original.

Most of this change was started off by the desire to rid the function of
chopped_off and current_prefix_length as they actually added very little to
the function since they only applied when computing the cindex.  I was able
to replace them mostly with just a check for the prefix match.  As long as
the prefix between the key and the node being tested was the same we know
we can search the tnode fully versus just testing cindex 0.

The second portion of the change ended up being a massive reordering.
Originally the calls to check_leaf were up near the start of the loop, and
the backtracing and descending into lower levels of tnodes was later.  This
didn't make much sense as the structure of the tree means the leaves are
always the last thing to be tested.  As such I reordered things so that we
instead have a loop that will delve into the tree and only exit when we
have either found a leaf or we have exhausted the tree.  The advantage of
rearranging things like this is that we can fully inline check_leaf since
there is now only one reference to it in the function.
Signed-off-by: NAlexander Duyck <alexander.h.duyck@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This change makes it so that leaf and tnode are the same struct.  As a
result there is no need for rt_trie_node anymore since everyting can be
merged into tnode.

On 32b systems this results in the leaf being 4 bytes larger, however I
don't know if that is really an issue as this and an eariler patch that
added bits & pos have increased the size from 20 to 28.  If I am not
mistaken slub/slab allocate on power of 2 sizes so 20 was likely being
rounded up to 32 anyway.
Signed-off-by: NAlexander Duyck <alexander.h.duyck@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Both the leaf and the tnode had an rcu_head in them, but they had them in
slightly different places.  Since we now have them in the same spot and
know that any node with bits == 0 is a leaf and the rest are either vmalloc
or kmalloc tnodes depending on the value of bits it makes it easy to combine
the functions and reduce overhead.

In addition I have taken advantage of the rcu_head pointer to go ahead and
put together a simple linked list instead of using the tnode pointer as
this way we can merge either type of structure for freeing.
Signed-off-by: NAlexander Duyck <alexander.h.duyck@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This change makes some fundamental changes to the way leaves and tnodes are
constructed.  The big differences are:
1.  Leaves now populate pos and bits indicating their full key size.
2.  Trie nodes now mask out their lower bits to be consistent with the leaf
3.  Both structures have been reordered so that rt_trie_node now consisists
    of a much larger region including the pos, bits, and rcu portions of
    the tnode structure.

On 32b systems this will result in the leaf being 4B larger as the pos and
bits values were added to a hole created by the key as it was only 4B in
length.
Signed-off-by: NAlexander Duyck <alexander.h.duyck@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The trie usage stats were currently being shared by all threads that were
calling fib_table_lookup.  As a result when multiple threads were
performing lookups simultaneously the trie would begin to cache bounce
between those threads.

In order to prevent this I have updated the usage stats to use a set of
percpu variables.  By doing this we should be able to avoid the cache
bouncing and still make use of these stats.
Signed-off-by: NAlexander Duyck <alexander.h.duyck@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch addresses an issue with the level compression of the fib_trie.
Specifically in the case of adding a new leaf that triggers a new node to
be added that takes the place of the old node.  The result is a trie where
the 1 child tnode is on one side and one leaf is on the other which gives
you a very deep trie.  Below is the script I used to generate a trie on
dummy0 with a 10.X.X.X family of addresses.

  ip link add type dummy
  ipval=184549374
  bit=2
  for i in `seq 1 23`
  do
    ifconfig dummy0:$bit $ipval/8
    ipval=`expr $ipval - $bit`
    bit=`expr $bit \* 2`
  done
  cat /proc/net/fib_triestat

Running the script before the patch:

	Local:
		Aver depth:     10.82
		Max depth:      23
		Leaves:         29
		Prefixes:       30
		Internal nodes: 27
		  1: 26  2: 1
		Pointers: 56
	Null ptrs: 1
	Total size: 5  kB

After applying the patch and repeating:

	Local:
		Aver depth:     4.72
		Max depth:      9
		Leaves:         29
		Prefixes:       30
		Internal nodes: 12
		  1: 3  2: 2  3: 7
		Pointers: 70
	Null ptrs: 30
	Total size: 4  kB

What this fix does is start the rebalance at the newly created tnode
instead of at the parent tnode.  This way if there is a gap between the
parent and the new node it doesn't prevent the new tnode from being
coalesced with any pre-existing nodes that may have been pushed into one
of the new nodes child branches.
Signed-off-by: NAlexander Duyck <alexander.h.duyck@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

All other add functions for lists have the new item as first argument
and the position where it is added as second argument.  This was changed
for no good reason in this function and makes using it unnecessary
confusing.

The name was changed to hlist_add_behind() to cause unconverted code to
generate a compile error instead of using the wrong parameter order.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: NKen Helias <kenhelias@firemail.de>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Acked-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>	[intel driver bits]
Cc: Hugh Dickins <hughd@google.com>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This reverts commit 30f38d2f.

fib_triestat is surrounded by a big lie: while it claims that it's a
seq_file (fib_triestat_seq_open, fib_triestat_seq_show), it isn't:

	static const struct file_operations fib_triestat_fops = {
	        .owner  = THIS_MODULE,
	        .open   = fib_triestat_seq_open,
	        .read   = seq_read,
	        .llseek = seq_lseek,
	        .release = single_release_net,
	};

Yes, fib_triestat is just a regular file.

A small detail (assuming CONFIG_NET_NS=y) is that while for seq_files
you could do seq_file_net() to get the net ptr, doing so for a regular
file would be wrong and would dereference an invalid pointer.

The fib_triestat lie claimed a victim, and trying to show the file would
be bad for the kernel. This patch just reverts the issue and fixes
fib_triestat, which still needs a rewrite to either be a seq_file or
stop claiming it is.
Signed-off-by: NSasha Levin <sasha.levin@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Make fib_triestat_seq_show consistent with other /proc/net files and
use seq_file_net.
Signed-off-by: NDavid Ahern <dsahern@gmail.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Cc: James Morris <jmorris@namei.org>
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: Patrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

All seq_printf() users are using "%n" for calculating padding size,
convert them to use seq_setwidth() / seq_pad() pair.
Signed-off-by: NTetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: NKees Cook <keescook@chromium.org>
Cc: Joe Perches <joe@perches.com>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This is a enhancement.

for the first node in fib_trie, newpos is 0, bit is 1.
Only for the leaf or node with unmatched key need calc pos.
Signed-off-by: Nbaker.zhang <baker.kernel@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Because 'node' is the i'st child of 'oldnode',
thus, here 'i' equals
tkey_extract_bits(node->key, oldtnode->pos, oldtnode->bits)

we just get 1 more bit,
and need not care the detail value of this bits.

I apologize for the mistake.

I generated the patch on a branch version,
and did not notice the put_child has been changed.

I have redone the test on HEAD version with my patch.

two cases are used.
case 1. inflate a node which has a leaf child node.
case 2: inflate a node which has a an child node with skipped bits

test env:
  ip link set eth0 up
  ip a add dev eth0 192.168.11.1/32
here, we just focus on route table(MAIN),
so I use a "192.168.11.1/32" address to simplify the test case.

call trace:
+ fib_insert_node
+ + trie_rebalance
+ + + resize
+ + + + inflate

Test case 1:  inflate a node which has a leaf child node.

===========================================================
step 1. prepare a fib trie
------------------------------------------
  ip r a 192.168.0.0/24 via 192.168.11.1
  ip r a 192.168.1.0/24 via 192.168.11.1

we get a fib trie.
root@baker:~# cat /proc/net/fib_trie
Main:
  +-- 192.168.0.0/23 1 0 0
   |-- 192.168.0.0
    /24 universe UNICAST
   |-- 192.168.1.0
    /24 universe UNICAST
Local:
.....

step 2. Add the third route
------------------------------------------
root@baker:~# ip r a 192.168.2.0/24 via 192.168.11.1

A fib_trie leaf will be inserted in fib_insert_node before trie_rebalance.

For function 'inflate':
'inflate' is called with following trie.
  +-- 192.168.0.0/22 1 1 0 <=== tn node
    +-- 192.168.0.0/23 1 0 0    <== node a
        |-- 192.168.0.0
          /24 universe UNICAST
        |-- 192.168.1.0
          /24 universe UNICAST
      |-- 192.168.2.0          <== leaf(node b)

When process node b, which is a leaf. here:
i is 1,
node key "192.168.2.0"
oldnode is (pos:22, bits:1)

unpatch source:
tkey_extract_bits(node->key, oldtnode->pos + oldtnode->bits, 1)
it equals:
tkey_extract_bits("192.168,2,0", 22 + 1, 1)

thus got 0, and call put_child(tn, 2*i, node); <== 2*i=2.

patched source:
tkey_extract_bits(node->key, oldtnode->pos, oldtnode->bits + 1),
tkey_extract_bits("192.168,2,0", 22, 1 + 1)  <== get 2.

Test case 2:  inflate a node which has a an child node with skipped bits
==========================================================================
step 1. prepare a fib trie.
  ip link set eth0 up
  ip a add dev eth0 192.168.11.1/32
  ip r a 192.168.128.0/24 via 192.168.11.1
  ip r a 192.168.0.0/24  via 192.168.11.1
  ip r a 192.168.16.0/24   via 192.168.11.1
  ip r a 192.168.32.0/24  via 192.168.11.1
  ip r a 192.168.48.0/24  via 192.168.11.1
  ip r a 192.168.144.0/24   via 192.168.11.1
  ip r a 192.168.160.0/24   via 192.168.11.1
  ip r a 192.168.176.0/24   via 192.168.11.1

check:
root@baker:~# cat /proc/net/fib_trie
Main:
  +-- 192.168.0.0/16 1 0 0
     +-- 192.168.0.0/18 2 0 0
        |-- 192.168.0.0
           /24 universe UNICAST
        |-- 192.168.16.0
           /24 universe UNICAST
        |-- 192.168.32.0
           /24 universe UNICAST
        |-- 192.168.48.0
           /24 universe UNICAST
     +-- 192.168.128.0/18 2 0 0
        |-- 192.168.128.0
           /24 universe UNICAST
        |-- 192.168.144.0
           /24 universe UNICAST
        |-- 192.168.160.0
           /24 universe UNICAST
        |-- 192.168.176.0
           /24 universe UNICAST
Local:
  ...

step 2. add a route to trigger inflate.
  ip r a 192.168.96.0/24   via 192.168.11.1

This command will call serveral times inflate.
In the first time, the fib_trie is:
________________________
+-- 192.168.128.0/(16, 1) <== tn node
 +-- 192.168.0.0/(17, 1)  <== node a
  +-- 192.168.0.0/(18, 2)
   |-- 192.168.0.0
   |-- 192.168.16.0
   |-- 192.168.32.0
   |-- 192.168.48.0
  |-- 192.168.96.0
 +-- 192.168.128.0/(18, 2) <== node b.
  |-- 192.168.128.0
  |-- 192.168.144.0
  |-- 192.168.160.0
  |-- 192.168.176.0

NOTE: node b is a interal node with skipped bits.
here,
i:1,
node->key "192.168.128.0",
oldnode:(pos:16, bits:1)
so
tkey_extract_bits(node->key, oldtnode->pos + oldtnode->bits, 1)
it equals:
tkey_extract_bits("192.168,128,0", 16 + 1, 1) <=== 0

tkey_extract_bits(node->key, oldtnode->pos, oldtnode->bits, 1)
it equals:
tkey_extract_bits("192.168,128,0", 16, 1+1) <=== 2

2*i + 0 == 2, so the result is same.
Signed-off-by: Nbaker.zhang <baker.kernel@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

AddressSanitizer [1] dynamic checker pointed a potential
out of bound access in leaf_walk_rcu()

We could allocate one more slot in tnode_new() to leave the prefetch()
in-place but it looks not worth the pain.

Bug added in commit 82cfbb00 ("[IPV4] fib_trie: iterator recode")

[1] :
https://code.google.com/p/address-sanitizer/wiki/AddressSanitizerForKernelReported-by: NAndrey Konovalov <andreyknvl@google.com>
Signed-off-by: NEric Dumazet <edumazet@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

With the <= max condition in the for loop, it will be always go 1
element further than needed. If the condition for the while loop is
never met, then max is MAX_STAT_DEPTH, and for loop will walk off the
end of nodesizes[].
Signed-off-by: NJerry Snitselaar <jerry.snitselaar@oracle.com>
Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Now that vfree() can be called from interrupt contexts, there's no
need to play games with schedule_work() to escape calling vfree()
from RCU callbacks.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

I'm not sure why, but the hlist for each entry iterators were conceived

        list_for_each_entry(pos, head, member)

The hlist ones were greedy and wanted an extra parameter:

        hlist_for_each_entry(tpos, pos, head, member)

Why did they need an extra pos parameter? I'm not quite sure. Not only
they don't really need it, it also prevents the iterator from looking
exactly like the list iterator, which is unfortunate.

Besides the semantic patch, there was some manual work required:

 - Fix up the actual hlist iterators in linux/list.h
 - Fix up the declaration of other iterators based on the hlist ones.
 - A very small amount of places were using the 'node' parameter, this
 was modified to use 'obj->member' instead.
 - Coccinelle didn't handle the hlist_for_each_entry_safe iterator
 properly, so those had to be fixed up manually.

The semantic patch which is mostly the work of Peter Senna Tschudin is here:

@@
iterator name hlist_for_each_entry, hlist_for_each_entry_continue, hlist_for_each_entry_from, hlist_for_each_entry_rcu, hlist_for_each_entry_rcu_bh, hlist_for_each_entry_continue_rcu_bh, for_each_busy_worker, ax25_uid_for_each, ax25_for_each, inet_bind_bucket_for_each, sctp_for_each_hentry, sk_for_each, sk_for_each_rcu, sk_for_each_from, sk_for_each_safe, sk_for_each_bound, hlist_for_each_entry_safe, hlist_for_each_entry_continue_rcu, nr_neigh_for_each, nr_neigh_for_each_safe, nr_node_for_each, nr_node_for_each_safe, for_each_gfn_indirect_valid_sp, for_each_gfn_sp, for_each_host;

type T;
expression a,c,d,e;
identifier b;
statement S;
@@

-T b;
    <+... when != b
(
hlist_for_each_entry(a,
- b,
c, d) S
|
hlist_for_each_entry_continue(a,
- b,
c) S
|
hlist_for_each_entry_from(a,
- b,
c) S
|
hlist_for_each_entry_rcu(a,
- b,
c, d) S
|
hlist_for_each_entry_rcu_bh(a,
- b,
c, d) S
|
hlist_for_each_entry_continue_rcu_bh(a,
- b,
c) S
|
for_each_busy_worker(a, c,
- b,
d) S
|
ax25_uid_for_each(a,
- b,
c) S
|
ax25_for_each(a,
- b,
c) S
|
inet_bind_bucket_for_each(a,
- b,
c) S
|
sctp_for_each_hentry(a,
- b,
c) S
|
sk_for_each(a,
- b,
c) S
|
sk_for_each_rcu(a,
- b,
c) S
|
sk_for_each_from
-(a, b)
+(a)
S
+ sk_for_each_from(a) S
|
sk_for_each_safe(a,
- b,
c, d) S
|
sk_for_each_bound(a,
- b,
c) S
|
hlist_for_each_entry_safe(a,
- b,
c, d, e) S
|
hlist_for_each_entry_continue_rcu(a,
- b,
c) S
|
nr_neigh_for_each(a,
- b,
c) S
|
nr_neigh_for_each_safe(a,
- b,
c, d) S
|
nr_node_for_each(a,
- b,
c) S
|
nr_node_for_each_safe(a,
- b,
c, d) S
|
- for_each_gfn_sp(a, c, d, b) S
+ for_each_gfn_sp(a, c, d) S
|
- for_each_gfn_indirect_valid_sp(a, c, d, b) S
+ for_each_gfn_indirect_valid_sp(a, c, d) S
|
for_each_host(a,
- b,
c) S
|
for_each_host_safe(a,
- b,
c, d) S
|
for_each_mesh_entry(a,
- b,
c, d) S
)
    ...+>

[akpm@linux-foundation.org: drop bogus change from net/ipv4/raw.c]
[akpm@linux-foundation.org: drop bogus hunk from net/ipv6/raw.c]
[akpm@linux-foundation.org: checkpatch fixes]
[akpm@linux-foundation.org: fix warnings]
[akpm@linux-foudnation.org: redo intrusive kvm changes]
Tested-by: NPeter Senna Tschudin <peter.senna@gmail.com>
Acked-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: NSasha Levin <sasha.levin@oracle.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Gleb Natapov <gleb@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

proc_net_remove is only used to remove proc entries
that under /proc/net,it's not a general function for
removing proc entries of netns. if we want to remove
some proc entries which under /proc/net/stat/, we still
need to call remove_proc_entry.

this patch use remove_proc_entry to replace proc_net_remove.
we can remove proc_net_remove after this patch.
Signed-off-by: NGao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Right now, some modules such as bonding use proc_create
to create proc entries under /proc/net/, and other modules
such as ipv4 use proc_net_fops_create.

It looks a little chaos.this patch changes all of
proc_net_fops_create to proc_create. we can remove
proc_net_fops_create after this patch.
Signed-off-by: NGao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Since route cache deletion (89aef892), delay is no
more used. Remove it.
Signed-off-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Acked-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It is a frequent mistake to confuse the netlink port identifier with a
process identifier.  Try to reduce this confusion by renaming fields
that hold port identifiers portid instead of pid.

I have carefully avoided changing the structures exported to
userspace to avoid changing the userspace API.

I have successfully built an allyesconfig kernel with this change.
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Since route cache deletion (89aef892), delay is no
more used. Remove it.
Signed-off-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Acked-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We've already found leaf, don't search for it again. Same is for fib leaf info.
Signed-off-by: NIgor Maravic <igorm@etf.rs>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

After IP route cache removal, I believe rcu_bh() has very little use and
we should remove this RCU variant, since it adds some cycles in fast
path.

Anyway, the call_rcu_bh() use in fib_true is obviously wrong, since
some users only assert rcu_read_lock().
Signed-off-by: NEric Dumazet <edumazet@google.com>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

__fls(x) is a bit faster than fls(x), granted we know x is non null.

As Ben Hutchings pointed out, fls(x) = __fls(x) + 1
Signed-off-by: NEric Dumazet <edumazet@google.com>
Cc: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The first parameter struct trie *t is not used anymore.
Remove it.
Signed-off-by: NLin Ming <mlin@ss.pku.edu.cn>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It should print size of struct rt_trie_node * allocated instead of size
of struct rt_trie_node.
Signed-off-by: NLin Ming <mlin@ss.pku.edu.cn>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>