Clean up in RX queue allocation. In netif_set_real_num_rx_queues
return error on attempt to set zero queues, or requested number is
greater than number of allocated queues. In netif_alloc_rx_queues,
do BUG_ON if queue_count is zero.
Signed-off-by: Tom Herbert <therbert@google.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In alloc_netdev_mq fail if requested queue_count < 1.
Signed-off-by: Tom Herbert <therbert@google.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The rx->count reference is used to track reference counts to the
number of rx-queue kobjects created for the device. This patch
eliminates initialization of the counter in netif_alloc_rx_queues
and instead increments the counter each time a kobject is created.
This is now symmetric with the decrement that is done when an object is
released.
Signed-off-by: Tom Herbert <therbert@google.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Synchronise the comment with the preceding implementation change.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Do not set num_rx_queues in netif_set_real_num_rx_queues() some
drivers will increase the real_num_rx_queues later due to a feature
changes or available interrupts increasing. By setting num_rx_queues
here this ends up creating a cap on the number of rx queues
available.
For example the ixgbe driver sets the max number of queues it intends
to use ever then sets the current number in use with the
netif_set_num_{rx|tx}_queues calls. With the current implementation
the number of rx queues gets limited so when a feature such as DCB
or FCoE is enabled the queues are no longer available.
kobjects will only be allocated for real_num_rx_queues so the waste
in memory is minimal.
Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In various situations, a device provides a packet to our stack and we
drop it before it enters protocol stack :
- softnet backlog full (accounted in /proc/net/softnet_stat)
- bad vlan tag (not accounted)
- unknown/unregistered protocol (not accounted)
We can handle a per-device counter of such dropped frames at core level,
and automatically adds it to the device provided stats (rx_dropped), so
that standard tools can be used (ifconfig, ip link, cat /proc/net/dev)
This is a generalization of commit 8990f468a (net: rx_dropped
accounting), thus reverting it.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
ingress being not used very much, and net_device->ingress_queue being
quite a big object (128 or 256 bytes), use a dynamic allocation if
needed (tc qdisc add dev eth0 ingress ...)
dev_ingress_queue(dev) helper should be used only with RTNL taken.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
There is some confusion with rx_queue name after RPS, and net drivers
private rx_queue fields.
I suggest to rename "struct net_device"->rx_queue to ingress_queue.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
As tunnel devices are going to be lockless, we need to make sure a
misconfigured machine wont enter an infinite loop.
Add a percpu variable, and limit to three the number of stacked xmits.
Reported-by: Jesse Gross <jesse@nicira.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
For RPS, we create a kobject for each RX queue based on the number of
queues passed to alloc_netdev_mq(). However, drivers generally do not
determine the numbers of hardware queues to use until much later, so
this usually represents the maximum number the driver may use and not
the actual number in use.
For TX queues, drivers can update the actual number using
netif_set_real_num_tx_queues(). Add a corresponding function for RX
queues, netif_set_real_num_rx_queues().
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Instead of having two places were we allocate dev->_rx, introduce
netif_alloc_rx_queues() helper and call it only from
register_netdevice(), not from alloc_netdev_mq()
Goal is to let drivers change dev->num_rx_queues after allocating netdev
and before registering it.
This also removes a lot of ifdefs in net/core/dev.c
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Automatically allows vlans to get NETIF_F_HIGHDMA if underlying device
supports it.
On 32bit arches (and more precisely if CONFIG_HIGHMEM is enabled), it
can help to reduce cost of illegal_highdma() and __skb_linearize()
calls.
Tested on tg3 , bnx2, bonding, this worked very well.
This is a generalization of a patch provided by Yi Zou & Jeff Kirsher.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
previously, if a vlan master device was moved from one network namespace
to another, all 802.1q and macvlan slaves were deleted.
we can use dev->reg_state to figure out whether dev_change_net_namespace
is happening, since that won't set dev->reg_state NETREG_UNREGISTERING.
so, this changes 8021q and macvlan to ignore NETDEV_UNREGISTER when
reg_state is not NETREG_UNREGISTERING.
Signed-off-by: David Lamparter <equinox@diac24.net>
Reviewed-by: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Daniel Lezcano <daniel.lezcano@free.fr>
Acked-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
rcu_dereference_raw() now needs to know the type of its argument.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently vlan devices don't have GRO by default as none of the Ethernet
drivers add NETIF_F_GRO to their vlan_features.
As GRO is a software feature add GRO to dev->vlan_features in
register_netdevice() and let vlan_dev_init() take care that it gets
enabled only when dev->features has NETIF_F_GRO too.
Signed-off-by: Brandon Philips <bphilips@suse.de>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
dev->ip_ptr is protected by rtnl and rcu.
Yet some places dont use appropriate primitives and/or locking rules.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
netdev_wait_allrefs() waits that all references to a device vanishes.
It currently uses a _very_ pessimistic 250 ms delay between each probe.
Some users reported that no more than 4 devices can be dismantled per
second, this is a pretty serious problem for some setups.
Most of the time, a refcount is about to be released by an RCU callback,
that is still in flight because rollback_registered_many() uses a
synchronize_rcu() call instead of rcu_barrier(). Problem is visible if
number of online cpus is one, because synchronize_rcu() is then a no op.
time to remove 50 ipip tunnels on a UP machine :
before patch : real 11.910s
after patch : real 1.250s
Reported-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Reported-by: Octavian Purdila <opurdila@ixiacom.com>
Reported-by: Benjamin LaHaise <bcrl@kvack.org>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When there is only one rps_cpus, skb_get_rxhash() can be eliminated.
Signed-off-by: Changli Gao <xiaosuo@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When a net device is implementing the select_queue callback and is part of
a bridge, frames coming from the bridge already have a tx queue associated
to the socket (introduced in commit a4ee3ce329,
"net: Use sk_tx_queue_mapping for connected sockets"). The call to
sk_tx_queue_get will then return the tx queue used by the bridge instead
of calling the select_queue callback.
In case of mac80211 this broke QoS which is implemented by using the
select_queue callback. Furthermore it introduced problems with rt2x00
because frames with the same TID and RA sometimes appeared on different
tx queues which the hw cannot handle correctly.
Fix this by always calling select_queue first if it is available and only
afterwards use the socket tx queue mapping.
Signed-off-by: Helmut Schaa <helmut.schaa@googlemail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add a small helper ptype_head() to get the head to manipulate
dev_add_pack() & __dev_remove_pack() can use a spinlock without
blocking BH, since softirq use RCU, and these functions are run from
process context only.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
- napi_gro_flush() is exported from net/core/dev.c, to avoid
an irq_save/irq_restore in the packet receive path.
- use napi_gro_receive() instead of netif_receive_skb()
- use napi_gro_flush() before calling __napi_complete()
- turn on NETIF_F_GRO by default
- Tested on a Marvell 88E8001 Gigabit NIC
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
compare_ether_header() can have a special implementation on 64 bit
arches if CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS is defined.
__napi_gro_receive() and vlan_gro_common() can avoid a conditional
branch to perform device match.
On x86_64, __napi_gro_receive() has now 38 instructions instead of 53
As gcc-4.4.3 still choose to not inline it, add inline keyword to this
performance critical function.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
CC: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
SKBs can be "fragmented" in two ways, via a page array (called
skb_shinfo(skb)->frags[]) and via a list of SKBs (called
skb_shinfo(skb)->frag_list).
Since skb_has_frags() tests the latter, it's name is confusing
since it sounds more like it's testing the former.
Signed-off-by: David S. Miller <davem@davemloft.net>
vlan_hwaccel_do_receive() always returns 0, so make it return void.
Signed-off-by: Changli Gao <xiaosuo@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
__skb_get_rxhash() was broken after the commit:
commit bfb564e739
Author: Krishna Kumar <krkumar2@in.ibm.com>
Date: Wed Aug 4 06:15:52 2010 +0000
core: Factor out flow calculation from get_rps_cpu
Signed-off-by: Changli Gao <xiaosuo@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fragmented IP packets may have no transfer header, so when computing
rxhash, we should skip them.
Signed-off-by: Changli Gao <xiaosuo@gmail.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
skb_get_rxhash() assumes the network header pointer of the skb is set
properly after the commit:
commit bfb564e739
Author: Krishna Kumar <krkumar2@in.ibm.com>
Date: Wed Aug 4 06:15:52 2010 +0000
core: Factor out flow calculation from get_rps_cpu
Signed-off-by: Changli Gao <xiaosuo@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch removes the abstraction introduced by the union skb_shared_tx in
the shared skb data.
The access of the different union elements at several places led to some
confusion about accessing the shared tx_flags e.g. in skb_orphan_try().
http://marc.info/?l=linux-netdev&m=128084897415886&w=2
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
>Xin Xiaohui wrote:
> I looked into the code dev_gro_receive(), found the code here:
> if the frags[0] is pulled to 0, then the page will be released,
> and memmove() frags left.
> Is that right? I'm not sure if memmove do right or not, but
> frags[0].size is never set after memove at least. what I think
> a simple way is not to do anything if we found frags[0].size == 0.
> The patch is as followed.
...
This version of the patch fixes the bug directly in memmove.
Reported-by: "Xin, Xiaohui" <xiaohui.xin@intel.com>
Signed-off-by: Jarek Poplawski <jarkao2@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Factor out flow calculation code from get_rps_cpu, since other
functions can use the same code.
Revisions:
v2 (Ben): Separate flow calcuation out and use in select queue.
v3 (Arnd): Don't re-implement MIN.
v4 (Changli): skb->data points to ethernet header in macvtap, and
make a fast path. Tested macvtap with this patch.
v5 (Changli):
- Cache skb->rxhash in skb_get_rxhash
- macvtap may not have pow(2) queues, so change code for
queue selection.
(Arnd):
- Use first available queue if all fails.
Signed-off-by: Krishna Kumar <krkumar2@in.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Although netif_rx() isn't expected to be called in process context with
preemption enabled, it'd better handle this case. And this is why get_cpu()
is used in the non-RPS #ifdef branch. If tree RCU is selected,
rcu_read_lock() won't disable preemption, so preempt_disable() should be
called explictly.
Signed-off-by: Changli Gao <xiaosuo@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The netpoll_rx_on() check in __napi_gro_receive() skips part of the
"common" GRO_NORMAL path, especially "pull:" in dev_gro_receive(),
where at least eth header should be copied for entirely paged skbs.
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>
This reverts commit 15e83ed788.
As explained by Johannes Berg, the optimization made here is
invalid. Or, at best, incomplete.
Not only destructor invocation, but conntract entry releasing
must be executed outside of hw IRQ context.
So just checking "skb->destructor" is insufficient.
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit ab95bfe01f replaces bridge and macvlan
hooks in __netif_receive_skb(), so dev.c doesn't need to include their headers.
Signed-off-by: Changli Gao <xiaosuo@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If user misconfigures ingress and causes a redirection loop, don't
overwhelm the log. This is also a error case so make it unlikely.
Found by inspection, luckily not in real system.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
With conn-track zones and probably with different network
namespaces, the netfilter logic needs to be re-calculated
on packet receive. If the netfilter logic is not reset,
it will not be recalculated properly. This patch adds
the nf_reset logic to dev_forward_skb.
Signed-off-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Conflicts:
drivers/vhost/net.c
net/bridge/br_device.c
Fix merge conflict in drivers/vhost/net.c with guidance from
Stephen Rothwell.
Revert the effects of net-2.6 commit 573201f36f
since net-next-2.6 has fixes that make bridge netpoll work properly thus
we don't need it disabled.
Signed-off-by: David S. Miller <davem@davemloft.net>
Since struct netdev_queue tx_bytes/tx_packets/tx_dropped are already
protected by _xmit_lock, its easy to convert these fields to u64 instead
of unsigned long.
This completes 64bit stats for devices using them (vlan, macvlan, ...)
Strictly, we could avoid the locking in dev_txq_stats_fold() on 64bit
arches, but its slow path and we prefer keep it simple.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds a new networking option to allow hardware time stamps
from PHY devices. When enabled, likely candidates among incoming and
outgoing network packets are offered to the PHY driver for possible
time stamping. When accepted by the PHY driver, incoming packets are
deferred for later delivery by the driver.
The patch also adds phylib driver methods for the SIOCSHWTSTAMP ioctl
and callbacks for transmit and receive time stamping. Drivers may
optionally implement these functions.
Signed-off-by: Richard Cochran <richard.cochran@omicron.at>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix problem in reading the tx_queue recorded in a socket. In
dev_pick_tx, the TX queue is read by doing a check with
sk_tx_queue_recorded on the socket, followed by a sk_tx_queue_get.
The problem is that there is not mutual exclusion across these
calls in the socket so it it is possible that the queue in the
sock can be invalidated after sk_tx_queue_recorded is called so
that sk_tx_queue get returns -1, which sets 65535 in queue_index
and thus dev_pick_tx returns 65536 which is a bogus queue and
can cause crash in dev_queue_xmit.
We fix this by only calling sk_tx_queue_get which does the proper
checks. The interface is that sk_tx_queue_get returns the TX queue
if the sock argument is non-NULL and TX queue is recorded, else it
returns -1. sk_tx_queue_recorded is no longer used so it can be
completely removed.
Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
commit fc6055a5ba (net: Introduce skb_orphan_try()) added early
orphaning of skbs.
This unfortunately added a performance regression in skb_tx_hash() in
case of stacked devices (bonding, vlans, ...)
Since skb->sk is now NULL, we cannot access sk->sk_hash anymore to
spread tx packets to multiple NIC queues on multiqueue devices.
skb_tx_hash() in this case only uses skb->protocol, same value for all
flows.
skb_orphan_try() can copy sk->sk_hash into skb->rxhash and skb_tx_hash()
can use this saved sk_hash value to compute its internal hash value.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Document that dev_get_stats() returns the same stats pointer it was
given. Remove const qualification from the returned pointer since the
caller may do what it likes with that structure.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In commit be1f3c2c02 "net: Enable 64-bit
net device statistics on 32-bit architectures" I redefined struct
net_device_stats so that it could be used in a union with struct
rtnl_link_stats64, avoiding the need for explicit copying or
conversion between the two. However, this is unsafe because there is
no locking required and no lock consistently held around calls to
dev_get_stats() and use of the statistics structure it returns.
In commit 28172739f0 "net: fix 64 bit
counters on 32 bit arches" Eric Dumazet dealt with that problem by
requiring callers of dev_get_stats() to provide storage for the
result. This means that the net_device::stats64 field and the padding
in struct net_device_stats are now redundant, so remove them.
Update the comment on net_device_ops::ndo_get_stats64 to reflect its
new usage.
Change dev_txq_stats_fold() to use struct rtnl_link_stats64, since
that is what all its callers are really using and it is no longer
going to be compatible with struct net_device_stats.
Eric Dumazet suggested the separate function for the structure
conversion.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>