I want to compile out proc_* and sysctl_* handlers totally and
stub them to NULL depending on config options, however usage of &
will prevent this, since taking adress of NULL pointer will break
compilation.
So, drop & in front of every ->proc_handler and every ->strategy
handler, it was never needed in fact.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch gets about 1.25% back on tbench regression.
My change to NAPI for multiqueue support changed the time limit on
network receive processing. Under sustained loads like tbench, this
can cause the receiver to reschedule prematurely.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Wireless HW without any dedicated queues for aggregation
do not need the ampdu_queues mechanism present right now
in mac80211. Since mac80211 is still incomplete wrt TX MQ
changes, do not allow aggregation sessions for drivers that
set ampdu_queues.
This is only an interim hack until Intel fixes the requeue issue.
Signed-off-by: Sujith <Sujith.Manoharan@atheros.com>
Signed-off-by: Luis Rodriguez <Luis.Rodriguez@Atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
netns ops which are registered with register_pernet_gen_device() are
shutdown strictly before those which are registered with
register_pernet_subsys(). Sometimes this leads to opposite (read: buggy)
shutdown ordering between two modules.
Add register_pernet_gen_subsys()/unregister_pernet_gen_subsys() for modules
which aren't elite enough for entry in struct net, and which can't use
register_pernet_gen_device(). PPTP conntracking module is such one.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Goals are :
1) Optimizing handling of incoming Unicast UDP frames, so that no memory
writes should happen in the fast path.
Note: Multicasts and broadcasts still will need to take a lock,
because doing a full lockless lookup in this case is difficult.
2) No expensive operations in the socket bind/unhash phases :
- No expensive synchronize_rcu() calls.
- No added rcu_head in socket structure, increasing memory needs,
but more important, forcing us to use call_rcu() calls,
that have the bad property of making sockets structure cold.
(rcu grace period between socket freeing and its potential reuse
make this socket being cold in CPU cache).
David did a previous patch using call_rcu() and noticed a 20%
impact on TCP connection rates.
Quoting Cristopher Lameter :
"Right. That results in cacheline cooldown. You'd want to recycle
the object as they are cache hot on a per cpu basis. That is screwed
up by the delayed regular rcu processing. We have seen multiple
regressions due to cacheline cooldown.
The only choice in cacheline hot sensitive areas is to deal with the
complexity that comes with SLAB_DESTROY_BY_RCU or give up on RCU."
- Because udp sockets are allocated from dedicated kmem_cache,
use of SLAB_DESTROY_BY_RCU can help here.
Theory of operation :
---------------------
As the lookup is lockfree (using rcu_read_lock()/rcu_read_unlock()),
special attention must be taken by readers and writers.
Use of SLAB_DESTROY_BY_RCU is tricky too, because a socket can be freed,
reused, inserted in a different chain or in worst case in the same chain
while readers could do lookups in the same time.
In order to avoid loops, a reader must check each socket found in a chain
really belongs to the chain the reader was traversing. If it finds a
mismatch, lookup must start again at the begining. This *restart* loop
is the reason we had to use rdlock for the multicast case, because
we dont want to send same message several times to the same socket.
We use RCU only for fast path.
Thus, /proc/net/udp still takes spinlocks.
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
call_rcu() will unconditionally rewrite RCU head anyway.
Applies to
struct neigh_parms
struct neigh_table
struct net
struct cipso_v4_doi
struct in_ifaddr
struct in_device
rt->u.dst
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
when testing the new pktgen module with multiple queues and ixgbe with:
pgset "flag QUEUE_MAP_CPU"
I found that I was getting errors in dmesg like:
pktgen: WARNING: QUEUE_MAP_CPU disabled because CPU count (8) exceeds number
<4>pktgen: WARNING: of tx queues (8) on eth15
you'll note, 8 really doesn't exceed 8.
This patch seemed to fix the logic errors and also the attempts at
limiting line length in printk (which didn't work anyway)
Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: Robert Olsson <robert.olsson@its.uu.se>
Signed-off-by: David S. Miller <davem@davemloft.net>
To make testing of the network namespace simpler allow
the network namespace code and the sysfs code to be
compiled and run at the same time. To do this only
virtual devices are allowed in the additional network
namespaces and those virtual devices are not placed
in the kobject tree.
Since virtual devices don't actually do anything interesting
hardware wise that needs device management there should
be no loss in keeping them out of the kobject tree and
by implication sysfs. The gain in ease of testing
and code coverage should be significant.
Changelog:
v2: As pointed out by Benjamin Thery it only makes sense to call
device_rename in the initial network namespace for now.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: Benjamin Thery <benjamin.thery@bull.net>
Tested-by: Serge Hallyn <serue@us.ibm.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Acked-by: Daniel Lezcano <dlezcano@fr.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This converts pretty much everything to print_mac. There were
a few things that had conflicts which I have just dropped for
now, no harm done.
I've built an allyesconfig with this and looked at the files
that weren't built very carefully, but it's a huge patch.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
My change
commit e2a6b85247
net: Enable TSO if supported by at least one device
didn't do what was intended because the netdev_compute_features
function was designed for conjunctions. So what happened was that
it would simply take the TSO status of the last constituent device.
This patch extends it to support both conjunctions and disjunctions
under the new name of netdev_increment_features.
It also adds a new function netdev_fix_features which does the
sanity checking that usually occurs upon registration. This ensures
that the computation doesn't result in an illegal combination
since this checking is absent when the change is initiated via
ethtool.
The two users of netdev_compute_features have been converted.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
If changename notifier returns an error code, it gets incorrectly
cleared during rollback so the error is never returned to the user.
Found while testing similar code for MTU changes.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Some code here depends on CONFIG_KMOD to not try to load
protocol modules or similar, replace by CONFIG_MODULES
where more than just request_module depends on CONFIG_KMOD
and and also use try_then_request_module in ebtables.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Clean up the various different email addresses of mine listed in the code
to a single current and valid address. As Dave says his network merges
for 2.6.28 are now done this seems a good point to send them in where
they won't risk disrupting real changes.
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Seems that skb goes into void unless something magic happened
in pskb_expand_head in case of failure.
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The unwind loop iterates down to -1 instead of stopping at 0 and ends up
accessing ->frags[-1].
Signed-off-by: Dimitris Michailidis <dm@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Conntrack code will use it for
a) removing expectations and helpers when corresponding module is removed, and
b) removing conntracks when L3 protocol conntrack module is removed.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Benjamin Thery tracked down a bug that explains many instances
of the error
unregister_netdevice: waiting for %s to become free. Usage count = %d
It turns out that netdev_run_todo can dead-lock with itself if
a second instance of it is run in a thread that will then free
a reference to the device waited on by the first instance.
The problem is really quite silly. We were trying to create
parallelism where none was required. As netdev_run_todo always
follows a RTNL section, and that todo tasks can only be added
with the RTNL held, by definition you should only need to wait
for the very ones that you've added and be done with it.
There is no need for a second mutex or spinlock.
This is exactly what the following patch does.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Jesper Dangaard Brouer <hawk@comx.dk> reported a bug when setting a VLAN
device down that is in promiscous mode:
When the VLAN device is set down, the promiscous count on the real
device is decremented by one by vlan_dev_stop(). When removing the
promiscous flag from the VLAN device afterwards, the promiscous
count on the real device is decremented a second time by the
vlan_change_rx_flags() callback.
The root cause for this is that the ->change_rx_flags() callback is
invoked while the device is down. The synchronization is meant to mirror
the behaviour of the ->set_rx_mode callbacks, meaning the ->open function
is responsible for doing a full sync on open, the ->close() function is
responsible for doing full cleanup on ->stop() and ->change_rx_flags()
is meant to do incremental changes while the device is UP.
Only invoke ->change_rx_flags() while the device is UP to provide the
intended behaviour.
Tested-by: Jesper Dangaard Brouer <jdb@comx.dk>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add some packet-split receive hooks.
For one this allows to do NUMA node affine page allocs. Later on these
hooks will be extended to do emergency reserve allocations for
fragments.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: David S. Miller <davem@davemloft.net>
Wrap calling sk->sk_backlog_rcv() in a function. This will allow extending the
generic sk_backlog_rcv behaviour.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: David S. Miller <davem@davemloft.net>
If the caller of pskb_expand_head specifies a negative nhead
we'll silently overwrite other people's memory. This patch
makes it BUG instead.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds skb_recycle_check(), which can be used by a network
driver after transmitting an skb to check whether this skb can be
recycled as a receive buffer.
skb_recycle_check() checks that the skb is not shared or cloned, and
that it is linear and its head portion large enough (as determined by
the driver) to be recycled as a receive buffer. If these conditions
are met, it does any necessary reference count dropping and cleans
up the skbuff as if it just came from __alloc_skb().
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add more docbook comments to network device functions and cleanup
the comments.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
dev_change_name and netdev_drivername should use const char on
parameters that are read-only input values. The strcpy to newname is
not needed since newname is not used later in function.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch removes the potentially allocated ifalias when the (new) given alias is empty.
E.g. when setting
echo "" > /sys/class/net/eth0/ifalias
Signed-off-by: Oliver Hartkopp <oliver@hartkopp.net>
Acked-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch add support for keeping an additional character alias
associated with an network interface. This is useful for maintaining
the SNMP ifAlias value which is a user defined value. Routers use this
to hold information like which circuit or line it is connected to. It
is just an arbitrary text label on the network device.
There are two exposed interfaces with this patch, the value can be
read/written either via netlink or sysfs.
This could be maintained just by the snmp daemon, but it is more
generally useful for other management tools, and the kernel is good
place to act as an agreed upon interface to store it.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently simple_tx_hash is hashing inside of udp fragments. As a result
packets are getting getting sent to all queues when they shouldn't be.
This causes a serious performance regression which can be seen by sending
UDP frames larger than mtu on multiqueue devices. This change will make
it so that fragments are hashed only as IP datagrams w/o any protocol
information.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The dst garbage collector dst_gc_task() may not be scheduled as we
expect it to be in __dst_free().
Indeed, when the dst_gc_timer was replaced by the delayed_work
dst_gc_work, the mod_timer() call used to schedule the garbage
collector at an earlier date was replaced by a schedule_delayed_work()
(see commit 86bba269d0).
But, the behaviour of mod_timer() and schedule_delayed_work() is
different in the way they handle the delay.
mod_timer() stops the timer and re-arm it with the new given delay,
whereas schedule_delayed_work() only check if the work is already
queued in the workqueue (and queue it (with delay) if it is not)
BUT it does NOT take into account the new delay (even if the new delay
is earlier in time).
schedule_delayed_work() returns 0 if it didn't queue the work,
but we don't check the return code in __dst_free().
If I understand the code in __dst_free() correctly, we want dst_gc_task
to be queued after DST_GC_INC jiffies if we pass the test (and not in
some undetermined time in the future), so I think we should add a call
to cancel_delayed_work() before schedule_delayed_work(). Patch below.
Or we should at least test the return code of schedule_delayed_work(),
and reset the values of dst_garbage.timer_inc and dst_garbage.timer_expires
back to their former values if schedule_delayed_work() failed.
Otherwise the subsequent calls to __dst_free will test the wrong values
and assume wrong thing about when the garbage collector is supposed to
be scheduled.
dst_gc_task() also calls schedule_delayed_work() without checking
its return code (or calling cancel_scheduled_work() first), but it
should fine there: dst_gc_task is the routine of the delayed_work, so
no dst_gc_work should be pending in the queue when it's running.
Signed-off-by: Benjamin Thery <benjamin.thery@bull.net>
Acked-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
As it stands users of netdev_compute_features (e.g., bridges/bonding)
will only enable TSO if all consituent devices support it. This
is unnecessarily pessimistic since even on devices that do not
support hardware TSO and SG, emulated TSO still performs to a par
with TSO off.
This patch enables TSO if at least on constituent device supports
it in hardware.
The direct beneficiaries will be virtualisation that uses bridging
since this means that TSO will always be enabled for communication
from the host to the guests.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
net_tx_action() can skip __QDISC_STATE_SCHED bit clearing while qdisc
is neither ran nor rescheduled, which may cause endless loop in
dev_deactivate().
Reported-by: Denys Fedoryshchenko <denys@visp.net.lb>
Tested-by: Denys Fedoryshchenko <denys@visp.net.lb>
Signed-off-by: Jarek Poplawski <jarkao2@gmail.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
If dev_deactivate() is trying to quiesce the queue, it
is theoretically possible for another cpu to livelock
trying to process that queue. This happens because
dev_deactivate() grabs the queue spinlock as it checks
the queue state, whereas net_tx_action() does a trylock
and reschedules the qdisc if it hits the lock.
This breaks the livelock by adding a check on
__QDISC_STATE_DEACTIVATED to net_tx_action() when
the trylock fails.
Based upon feedback from Herbert Xu and Jarek Poplawski.
Signed-off-by: David S. Miller <davem@davemloft.net>
This reverts commit d4766692e7.
qdisc_destroy() now runs in RTNL fully again, so this
change is no longer needed.
Signed-off-by: David S. Miller <davem@davemloft.net>
Change handling of the __QDISC_STATE_SCHED flag in net_tx_action() to
enable proper control in dev_deactivate(). Now, if this flag is seen
as unset under root_lock means a qdisc can't be netif_scheduled.
Signed-off-by: Jarek Poplawski <jarkao2@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This new state lets dev_deactivate() mark a qdisc as having been
deactivated.
dev_queue_xmit() and ing_filter() check for this bit and do not
try to process the qdisc if the bit is set.
dev_deactivate() polls the qdisc after setting the bit, waiting
for both __QDISC_STATE_RUNNING and __QDISC_STATE_SCHED to clear.
This isn't perfect yet, but subsequent changesets will make it so.
This part is just one piece of the puzzle.
Signed-off-by: David S. Miller <davem@davemloft.net>
There's an skb_copy_datagram_iovec() to copy out of a paged skb, but
nothing the other way around (because we don't do that).
We want to allocate big skbs in tun.c, so let's add the function.
It's a carbon copy of skb_copy_datagram_iovec() with enough changes to
be annoying.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
skb_gso_segment didn't preserve some attributes in the original skb
such as the netfilter fields. This was harmless until they were used
which is the case for packets going through lo.
This patch makes it call __copy_skb_header which also picks up some
other missing attributes.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
gen_kill_estimator() required rtnl_lock() protection, but since it is
moved to an RCU callback __qdisc_destroy() let's use est_lock instead.
Signed-off-by: Jarek Poplawski <jarkao2@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
With the new multi-queue transmit code, it is possible to accidentally
make pktgen pick a non-existing tx queue simply by using a stale
script to drive pktgen. Access to this non-existing tx queue will
then trigger a bad memory access and kill the machine.
For example, setting "queue_map_max 2" will cause my machine to die
when accessing a garbage spinlock in the non-existing tx queue:
BUG: spinlock bad magic on CPU#0, kpktgend_0/564
lock: ffff88001ddf6718, .magic: ffffffff, .owner: /-1, .owner_cpu: 0
Pid: 564, comm: kpktgend_0 Not tainted 2.6.27-rc3 #35
Call Trace:
[<ffffffff803a1228>] spin_bug+0xa4/0xac
[<ffffffff803a1253>] _raw_spin_lock+0x23/0x123
[<ffffffff8055b06f>] _spin_lock_bh+0x17/0x1b
[<ffffffff804cb57d>] pktgen_thread_worker+0xa97/0x1002
[<ffffffff8022874d>] ? finish_task_switch+0x38/0x97
[<ffffffff80242077>] ? autoremove_wake_function+0x0/0x36
[<ffffffff80242077>] ? autoremove_wake_function+0x0/0x36
[<ffffffff804caae6>] ? pktgen_thread_worker+0x0/0x1002
[<ffffffff80241a40>] kthread+0x44/0x6d
[<ffffffff8020c399>] child_rip+0xa/0x11
[<ffffffff802419fc>] ? kthread+0x0/0x6d
[<ffffffff8020c38f>] ? child_rip+0x0/0x11
The attached patch adds some sanity checking to prevent
these sorts of configuration errors.
Signed-off-by: Andrew Gallatin <gallatin@myri.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
