While doing profile analysis, I found fib_hash_table was sometime in a
cache line shared by a possibly often written kernel structure.
(CONFIG_IP_ROUTE_MULTIPATH || !CONFIG_IPV6_MULTIPLE_TABLES)
It's hard to detect because not easily reproductible.
Make sure we allocate a full cache line to keep this shared in all cpus
caches.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
remove useless union keyword in rtable, rt6_info and dn_route.
Since there is only one member in a union, the union keyword isn't useful.
Signed-off-by: Changli Gao <xiaosuo@gmail.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Sparse can help us find endianness bugs, but we need to make some
cleanups to be able to more easily spot real bugs.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
addr_bit_test() is used in various places in IPv6 routing table
subsystem. It checks if the given fn_bit is set,
where fn_bit counts bits from MSB in words in network-order.
fn_bit : 0 .... 31 32 .... 64 65 .... 95 96 ....127
fn_bit >> 5 gives offset of word, and (~fn_bit & 0x1f) gives
count from LSB in the network-endian word in question.
fn_bit >> 5 : 0 1 2 3
~fn_bit & 0x1f: 31 .... 0 31 .... 0 31 .... 0 31 .... 0
Thus, the mask was generated as htonl(1 << (~fn_bit & 0x1f)).
This can be optimized by "sweezle" (See include/asm-generic/bitops/le.h).
In little-endian,
htonl(1 << bit) = 1 << (bit ^ BITOP_BE32_SWIZZLE)
where
BITOP_BE32_SWIZZLE is (0x1f & ~7)
So,
htonl(1 << (~fn_bit & 0x1f)) = 1 << ((~fn_bit & 0x1f) ^ (0x1f & ~7))
= 1 << ((~fn_bit ^ ~7) & 0x1f)
= 1 << ((~fn_bit ^ BITOP_BE32_SWIZZLE) & 0x1f)
In big-endian, BITOP_BE32_SWIZZLE is equal to 0.
1 << ((~fn_bit ^ BITOP_BE32_SWIZZLE) & 0x1f)
= 1 << ((~fn_bit) & 0x1f)
= htonl(1 << (~fn_bit & 0x1f))
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
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: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
When the fib size exceeds what can be dumped in a single skb, the
dump is suspended and resumed once the last skb has been received
by userspace. When the fib is changed while the dump is suspended,
the walker might contain stale pointers, causing a crash when the
dump is resumed.
BUG: unable to handle kernel NULL pointer dereference at 0000000000000018
IP: [<ffffffffa01bce04>] fib6_walk_continue+0xbb/0x124 [ipv6]
PGD 5347a067 PUD 65c7067 PMD 0
Oops: 0000 [#1] PREEMPT SMP
...
RIP: 0010:[<ffffffffa01bce04>]
[<ffffffffa01bce04>] fib6_walk_continue+0xbb/0x124 [ipv6]
...
Call Trace:
[<ffffffff8104aca3>] ? mutex_spin_on_owner+0x59/0x71
[<ffffffffa01bd105>] inet6_dump_fib+0x11b/0x1b9 [ipv6]
[<ffffffff81371af4>] netlink_dump+0x5b/0x19e
[<ffffffff8134f288>] ? consume_skb+0x28/0x2a
[<ffffffff81373b69>] netlink_recvmsg+0x1ab/0x2c6
[<ffffffff81372781>] ? netlink_unicast+0xfa/0x151
[<ffffffff813483e0>] __sock_recvmsg+0x6d/0x79
[<ffffffff81348a53>] sock_recvmsg+0xca/0xe3
[<ffffffff81066d4b>] ? autoremove_wake_function+0x0/0x38
[<ffffffff811ed1f8>] ? radix_tree_lookup_slot+0xe/0x10
[<ffffffff810b3ed7>] ? find_get_page+0x90/0xa5
[<ffffffff810b5dc5>] ? filemap_fault+0x201/0x34f
[<ffffffff810ef152>] ? fget_light+0x2f/0xac
[<ffffffff813519e7>] ? verify_iovec+0x4f/0x94
[<ffffffff81349a65>] sys_recvmsg+0x14d/0x223
Store the serial number when beginning to walk the fib and reload
pointers when continuing to walk after a change occured. Similar
to other dumping functions, this might cause unrelated entries to
be missed when entries are deleted.
Tested-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
__net_init/__net_exit are apparently not going away, so use them
to full extent.
In some cases __net_init was removed, because it was called from
__net_exit code.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Choose saner defaults for xfrm[4|6] gc_thresh values on init
Currently, the xfrm[4|6] code has hard-coded initial gc_thresh values
(set to 1024). Given that the ipv4 and ipv6 routing caches are sized
dynamically at boot time, the static selections can be non-sensical.
This patch dynamically selects an appropriate gc threshold based on
the corresponding main routing table size, using the assumption that
we should in the worst case be able to handle as many connections as
the routing table can.
For ipv4, the maximum route cache size is 16 * the number of hash
buckets in the route cache. Given that xfrm4 starts garbage
collection at the gc_thresh and prevents new allocations at 2 *
gc_thresh, we set gc_thresh to half the maximum route cache size.
For ipv6, its a bit trickier. there is no maximum route cache size,
but the ipv6 dst_ops gc_thresh is statically set to 1024. It seems
sane to select a simmilar gc_thresh for the xfrm6 code that is half
the number of hash buckets in the v6 route cache times 16 (like the v4
code does).
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When a fib6 table dump is prematurely ended, we won't unlink
its walker from the list. This causes all sorts of grief for
other users of the list later.
Reported-by: Chris Caputo <ccaputo@alt.net>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
ipv6_dev_get_saddr() blindly de-references dst_dev to get the network
namespace, but some callers might pass NULL. Change callers to pass a
namespace pointer instead.
Signed-off-by: Brian Haley <brian.haley@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Removes legacy reinvent-the-wheel type thing. The generic
machinery integrates much better to automated debugging aids
such as kerneloops.org (and others), and is unambiguous due to
better naming. Non-intuively BUG_TRAP() is actually equal to
WARN_ON() rather than BUG_ON() though some might actually be
promoted to BUG_ON() but I left that to future.
I could make at least one BUILD_BUG_ON conversion.
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
Change icmp6_dst_gc to return the one value the caller cares about rather
than using call by reference.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Now there is spin_trylock_bh, use it rather than open coding.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This timer normally happens once a minute, there is no need to cause an
early wakeup for it, so align it to next second boundary to safe power.
It can't be deferred because then it could take too long on cleanup or DoS.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
FIB timer list is a trivial size structure, avoid indirection and just
put it in existing ns.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This fixes the bridge reference count problem and cleanups ipv6 FIB
timer management. Don't use expires field, because it is not a proper
way to test, instead use timer_pending().
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch removes CVS keywords that weren't updated for a long time
from comments.
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The del_timer() function doesn't guarantee, that the timer callback
is not active by the time it exits.
Thus, the fib6_net_exit() may kfree() all the data, that is required
by the fib6_run_gc(). The race window is tiny, but slab poisoning can
trigger this bug.
Using del_timer_sync() will cure this.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fixes bugzilla #8895
If a super-tree leaf has 'rt' assigned to it and we
get an error from fib6_add_rt2node(), we'll leave
a reference to 'rt' in pn->leaf and then do an
unconditional dst_free().
We should prune such references.
Based upon a report by Vincent Perrier.
Signed-off-by: David S. Miller <davem@davemloft.net>
Introduce per-sock inlines: sock_net(), sock_net_set()
and per-inet_timewait_sock inlines: twsk_net(), twsk_net_set().
Without CONFIG_NET_NS, no namespace other than &init_net exists.
Let's explicitly define them to help compiler optimizations.
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
The rt6_info structures are moved inside the network namespace
structure. All references to these structures are now relative to the
initial network namespace.
Signed-off-by: Daniel Lezcano <dlezcano@fr.ibm.com>
Signed-off-by: Benjamin Thery <benjamin.thery@bull.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch make mindless changes and prepares the code to use dynamic
allocation for rt6_info structure. The code accesses the rt6_info
structure as a pointer instead of a global static variable.
Signed-off-by: Daniel Lezcano <dlezcano@fr.ibm.com>
Signed-off-by: Benjamin Thery <benjamin.thery@bull.net>
Signed-off-by: David S. Miller <davem@davemloft.net>