linux-toradex.git/net/core/dev.c, branch v3.0.16

rtnetlink: Add missing manual netlink notification in dev_change_net_namespaces

2011-11-11T17:35:50+00:00

commit d2237d35748e7f448a9c2d9dc6a85ef637466e24 upstream.

Renato Westphal noticed that since commit a2835763e130c343ace5320c20d33c281e7097b7
"rtnetlink: handle rtnl_link netlink notifications manually" was merged
we no longer send a netlink message when a networking device is moved
from one network namespace to another.

Fix this by adding the missing manual notification in dev_change_net_namespaces.

Since all network devices that are processed by dev_change_net_namspaces are
in the initialized state the complicated tests that guard the manual
rtmsg_ifinfo calls in rollback_registered and register_netdevice are
unnecessary and we can just perform a plain notification.

Tested-by: Renato Westphal 
Signed-off-by: Eric W. Biederman 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

vlan: Fix the ingress VLAN_FLAG_REORDER_HDR check

2011-06-11T23:15:50+00:00

Testing of VLAN_FLAG_REORDER_HDR does not belong in vlan_untag
but rather in vlan_do_receive.  Otherwise the vlan header
will not be properly put on the packet in the case of
vlan header accelleration.

As we remove the check from vlan_check_reorder_header
rename it vlan_reorder_header to keep the naming clean.

Fix up the skb->pkt_type early so we don't look at the packet
after adding the vlan tag, which guarantees we don't goof
and look at the wrong field.

Use a simple if statement instead of a complicated switch
statement to decided that we need to increment rx_stats
for a multicast packet.

Hopefully at somepoint we will just declare the case where
VLAN_FLAG_REORDER_HDR is cleared as unsupported and remove
the code.  Until then this keeps it working correctly.

Signed-off-by: Eric W. Biederman 
Signed-off-by: Jiri Pirko 
Acked-by: Changli Gao 
Signed-off-by: David S. Miller

net: cpu offline cause napi stall

2011-06-07T08:01:22+00:00

Frank Blaschka reported :

  During heavy network load we turn off/on cpus.
  Sometimes this causes a stall on the network device.
  Digging into the dump I found out following:

  napi is scheduled but does not run. From the I/O buffers
  and the napi state I see napi/rx_softirq processing has stopped
  because the budget was reached. napi stays in the
  softnet_data poll_list and the rx_softirq was raised again.

  I assume at this time the cpu offline comes in,
  the rx softirq is raised/moved to another cpu but napi stays in the
  poll_list of the softnet_data of the now offline cpu.

  Reviewing dev_cpu_callback (net/core/dev.c) I did not find the
  poll_list is transfered to the new cpu.


This patch is a straightforward implementation of Frank suggestion :

Transfert poll_list and trigger NET_RX_SOFTIRQ on new cpu.

Reported-by: Frank Blaschka 
Signed-off-by: Heiko Carstens 
Signed-off-by: Eric Dumazet 
Tested-by: Eric Dumazet 
Signed-off-by: David S. Miller

net: Rework netdev_drivername() to avoid warning.

2011-06-06T23:41:33+00:00

This interface uses a temporary buffer, but for no real reason.
And now can generate warnings like:

net/sched/sch_generic.c: In function dev_watchdog
net/sched/sch_generic.c:254:10: warning: unused variable drivername

Just return driver->name directly or "".

Reported-by: Connor Hansen 
Signed-off-by: David S. Miller

net: tracepoint of net_dev_xmit sees freed skb and causes panic

2011-06-02T21:06:31+00:00

Because there is a possibility that skb is kfree_skb()ed and zero cleared
after ndo_start_xmit, we should not see the contents of skb like skb->len and
skb->dev->name after ndo_start_xmit. But trace_net_dev_xmit does that
and causes panic by NULL pointer dereference.
This patch fixes trace_net_dev_xmit not to see the contents of skb directly.

If you want to reproduce this panic,

1. Get tracepoint of net_dev_xmit on
2. Create 2 guests on KVM
2. Make 2 guests use virtio_net
4. Execute netperf from one to another for a long time as a network burden
5. host will panic(It takes about 30 minutes)

Signed-off-by: Koki Sanagi 
Signed-off-by: David S. Miller

net: make dev_disable_lro use physical device if passed a vlan dev (v2)

2011-05-25T21:55:25+00:00

If the device passed into dev_disable_lro is a vlan, then repoint the dev
poniter so that we actually modify the underlying physical device.

Signed-of-by: Neil Horman 
CC: davem@davemloft.net
CC: bhutchings@solarflare.com

Signed-off-by: David S. Miller

net: use synchronize_rcu_expedited()

2011-05-24T17:26:12+00:00

synchronize_rcu() is very slow in various situations (HZ=100,
CONFIG_NO_HZ=y, CONFIG_PREEMPT=n)

Extract from my (mostly idle) 8 core machine :

 synchronize_rcu() in 99985 us
 synchronize_rcu() in 79982 us
 synchronize_rcu() in 87612 us
 synchronize_rcu() in 79827 us
 synchronize_rcu() in 109860 us
 synchronize_rcu() in 98039 us
 synchronize_rcu() in 89841 us
 synchronize_rcu() in 79842 us
 synchronize_rcu() in 80151 us
 synchronize_rcu() in 119833 us
 synchronize_rcu() in 99858 us
 synchronize_rcu() in 73999 us
 synchronize_rcu() in 79855 us
 synchronize_rcu() in 79853 us

When we hold RTNL mutex, we would like to spend some cpu cycles but not
block too long other processes waiting for this mutex.

We also want to setup/dismantle network features as fast as possible at
boot/shutdown time.

This patch makes synchronize_net() call the expedited version if RTNL is
locked.

synchronize_rcu_expedited() typical delay is about 20 us on my machine.

 synchronize_rcu_expedited() in 18 us
 synchronize_rcu_expedited() in 18 us
 synchronize_rcu_expedited() in 18 us
 synchronize_rcu_expedited() in 18 us
 synchronize_rcu_expedited() in 20 us
 synchronize_rcu_expedited() in 16 us
 synchronize_rcu_expedited() in 20 us
 synchronize_rcu_expedited() in 18 us
 synchronize_rcu_expedited() in 18 us

Signed-off-by: Eric Dumazet 
CC: Paul E. McKenney 
CC: Ben Greear 
Reviewed-by: Paul E. McKenney 
Signed-off-by: David S. Miller

net: remove synchronize_net() from netdev_set_master()

2011-05-23T01:01:20+00:00

In the old days, we used to access dev->master in __netif_receive_skb()
in a rcu_read_lock section.

So one synchronize_net() call was needed in netdev_set_master() to make
sure another cpu could not use old master while/after we release it.

We now use netdev_rx_handler infrastructure and added one
synchronize_net() call in bond_release()/bond_release_all()

Remove the obsolete synchronize_net() from netdev_set_master() and add
one in bridge del_nbp() after its netdev_rx_handler_unregister() call.

This makes enslave -d a bit faster.

Signed-off-by: Eric Dumazet 
CC: Jiri Pirko 
CC: Stephen Hemminger 
Signed-off-by: David S. Miller

macvlan: remove one synchronize_rcu() call

2011-05-20T04:33:18+00:00

When one macvlan device is dismantled, we can avoid one
synchronize_rcu() call done after deletion from hash list, since caller
will perform a synchronize_net() call after its ndo_stop() call.

Add a new netdev->dismantle field to signal this dismantle intent.

Reduces RTNL hold time.

Signed-off-by: Eric Dumazet 
CC: Patrick McHardy 
CC: Ben Greear 
Signed-off-by: David S. Miller

Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6

2011-05-17T21:33:11+00:00

Conflicts:
	drivers/net/vmxnet3/vmxnet3_ethtool.c
	net/core/dev.c