This patch aims to extend round-robin mode with a new option called
packets_per_slave which can have the following values and effects:
0 - choose a random slave
1 (default) - standard round-robin, 1 packet per slave
>1 - round-robin when >1 packets have been transmitted per slave
The allowed values are between 0 and 65535.
This patch also fixes the comment style in bond_xmit_roundrobin().
Signed-off-by: Nikolay Aleksandrov <nikolay@redhat.com>
Acked-by: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
There is an extra semi-colon so bond_get_size() doesn't return the
correct value.
Fixes: ec76aa4985 ('bonding: add Netlink support active_slave option')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Veaceslav Falico <vfalico@redhat.com>
Reviewed-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: David S. Miller <davem@davemloft.net>
This reverts commit 4d961a101e, reversing
changes made to a00f6fcc7d.
Revert bond locking changes, they cause regressions and Veaceslav Falico
doesn't like how the commit messages were done at all.
Signed-off-by: David S. Miller <davem@davemloft.net>
The bond slave list may change when the monitor is running, the slave list is no longer
protected by bond->lock, only protected by rtnl lock(), so we have 3 ways to modify it:
1.add bond_master_upper_dev_link() and bond_upper_dev_unlink() in bond->lock, but it is unsafe
to call call_netdevice_notifiers() in write lock.
2.remove unused bond->lock for monitor function, only use the existing rtnl lock().
3.use rcu_read_lock() to protect it, of course, it will transform bond_for_each_slave to
bond_for_each_slave_rcu() and performance is better, but in slow path, it is ignored.
so I remove the bond->lock and move the rtnl lock to protect the whole monitor function.
Signed-off-by: Ding Tianhong <dingtianhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The bond slave list may change when the monitor is running, the slave list is no longer
protected by bond->lock, only protected by rtnl lock(), so we have 3 ways to modify it:
1.add bond_master_upper_dev_link() and bond_upper_dev_unlink() in bond->lock, but it is unsafe
to call call_netdevice_notifiers() in write lock.
2.remove unused bond->lock for monitor function, only use the existing rtnl lock().
3.use rcu_read_lock() to protect it, of course, it will transform bond_for_each_slave to
bond_for_each_slave_rcu() and performance is better, but in slow path, it is ignored.
so I remove the bond->lock and move the rtnl lock to protect the whole monitor function.
Signed-off-by: Ding Tianhong <dingtianhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The bond slave list may change when the monitor is running, the slave list is no longer
protected by bond->lock, only protected by rtnl lock(), so we have 3 ways to modify it:
1.add bond_master_upper_dev_link() and bond_upper_dev_unlink() in bond->lock, but it is unsafe
to call call_netdevice_notifiers() in write lock.
2.remove unused bond->lock for monitor function, only use the existing rtnl lock().
3.use rcu_read_lock() to protect it, of course, it will transform bond_for_each_slave to
bond_for_each_slave_rcu() and performance is better, but in slow path, it is ignored.
so I remove the bond->lock and add the rtnl lock to protect the whole monitor function.
Signed-off-by: Ding Tianhong <dingtianhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The bond slave list may change when the monitor is running, the slave list is no longer
protected by bond->lock, only protected by rtnl lock(), so we have 3 ways to modify it:
1.add bond_master_upper_dev_link() and bond_upper_dev_unlink() in bond->lock, but it is unsafe
to call call_netdevice_notifiers() in write lock.
2.remove unused bond->lock for monitor function, only use the existing rtnl lock().
3.use rcu_read_lock() to protect it, of course, it will transform bond_for_each_slave to
bond_for_each_slave_rcu() and performance is better, but in slow path, it is ignored.
so I remove the bond->lock and move the rtnl lock to protect the whole monitor function.
Signed-off-by: Ding Tianhong <dingtianhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The bond slave list may change when the monitor is running, the slave list is no longer
protected by bond->lock, only protected by rtnl lock(), so we have 3 ways to modify it:
1.add bond_master_upper_dev_link() and bond_upper_dev_unlink() in bond->lock, but it is unsafe
to call call_netdevice_notifiers() in write lock.
2.remove unused bond->lock for monitor function, only use the existing rtnl lock().
3.use rcu_read_lock() to protect it, of course, it will transform bond_for_each_slave to
bond_for_each_slave_rcu() and performance is better, but in slow path, it is ignored.
so I remove the bond->lock and move the rtnl lock to protect the whole monitor function.
Signed-off-by: Ding Tianhong <dingtianhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
As Jiri noted, currently we first do all bonding-specific initialization
(specifically - bond_select_active_slave(bond)) before we actually attach
the slave (so that it becomes visible through bond_for_each_slave() and
friends). This might result in bond_select_active_slave() not seeing the
first/new slave and, thus, not actually selecting an active slave.
Fix this by moving all the bond-related init part after we've actually
completely initialized and linked (via bond_master_upper_dev_link()) the
new slave.
Also, remove the bond_(de/a)ttach_slave(), it's useless to have functions
to ++/-- one int.
After this we have all the initialization of the new slave *before*
linking, and all the stuff that needs to be done on bonding *after* it. It
has also a bonus effect - we can remove the locking on the new slave init
completely, and only use it for bond_select_active_slave().
Reported-by: Jiri Pirko <jiri@resnulli.us>
CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
Acked-by: Ding Tianhong@huawei.com
Reviewed-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: David S. Miller <davem@davemloft.net>
no longer needed since bond_option_active_slave_set() can be used
instead.
Signed-off-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: David S. Miller <davem@davemloft.net>
The bond_for_each_slave() will not be protected by read_lock(),
only protected by rtnl_lock(), so need to replace read_lock()
with rtnl_lock().
Signed-off-by: Ding Tianhong <dingtianhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The commit 278b208375
(bonding: initial RCU conversion) has convert the roundrobin,
active-backup, broadcast and xor xmit path to rcu protection,
the performance will be better for these mode, so this time,
convert xmit path for alb mode.
Signed-off-by: Ding Tianhong <dingtianhong@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Cc: Nikolay Aleksandrov <nikolay@redhat.com>
Cc: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The commit 278b208375
(bonding: initial RCU conversion) has convert the roundrobin,
active-backup, broadcast and xor xmit path to rcu protection,
the performance will be better for these mode, so this time,
convert xmit path for 3ad mode.
Suggested-by: Nikolay Aleksandrov <nikolay@redhat.com>
Suggested-by: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: Ding Tianhong <dingtianhong@huawei.com>
Signed-off-by: Wang Yufen <wangyufen@huawei.com>
Cc: Nikolay Aleksandrov <nikolay@redhat.com>
Cc: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently, in TLB mode we change mac addresses only by memcpy-ing the to
net_device->dev_addr, without actually setting them via
dev_set_mac_address(). This permits us to receive all the traffic always on
one mac address.
However, in case the interface flips, some drivers might enforce the
mac filtering for its FW/HW based on current ->dev_addr, and thus we won't
be able to receive traffic on that interface, in case it will be selected
as active in TLB mode.
Fix it by setting the mac address forcefully on every new active slave that
we select in TLB mode.
CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
CC: Yuval Mintz <yuvalmin@broadcom.com>
Reported-by: Yuval Mintz <yuvalmin@broadcom.com>
Tested-by: Yuval Mintz <yuvalmin@broadcom.com>
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds two new hash policy modes which use skb_flow_dissect:
3 - Encapsulated layer 2+3
4 - Encapsulated layer 3+4
There should be a good improvement for tunnel users in those modes.
It also changes the old hash functions to:
hash ^= (__force u32)flow.dst ^ (__force u32)flow.src;
hash ^= (hash >> 16);
hash ^= (hash >> 8);
Where hash will be initialized either to L2 hash, that is
SRCMAC[5] XOR DSTMAC[5], or to flow->ports which should be extracted
from the upper layer. Flow's dst and src are also extracted based on the
xmit policy either directly from the buffer or by using skb_flow_dissect,
but in both cases if the protocol is IPv6 then dst and src are obtained by
ipv6_addr_hash() on the real addresses. In case of a non-dissectable
packet, the algorithms fall back to L2 hashing.
The bond_set_mode_ops() function is now obsolete and thus deleted
because it was used only to set the proper hash policy. Also we trim a
pointer from struct bonding because we no longer need to keep the hash
function, now there's only a single hash function - bond_xmit_hash that
works based on bond->params.xmit_policy.
The hash function and skb_flow_dissect were suggested by Eric Dumazet.
The layer names were suggested by Andy Gospodarek, because I suck at
semantics.
Signed-off-by: Nikolay Aleksandrov <nikolay@redhat.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Acked-by: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Conflicts:
drivers/net/ethernet/emulex/benet/be.h
drivers/net/usb/qmi_wwan.c
drivers/net/wireless/brcm80211/brcmfmac/dhd_bus.h
include/net/netfilter/nf_conntrack_synproxy.h
include/net/secure_seq.h
The conflicts are of two varieties:
1) Conflicts with Joe Perches's 'extern' removal from header file
function declarations. Usually it's an argument signature change
or a function being added/removed. The resolutions are trivial.
2) Some overlapping changes in qmi_wwan.c and be.h, one commit adds
a new value, another changes an existing value. That sort of
thing.
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently we rely on rtnl locking in bond_set_rx_mode(), however it's not
always the case:
RTNL: assertion failed at drivers/net/bonding/bond_main.c (3391)
...
[<ffffffff81651ca5>] dump_stack+0x54/0x74
[<ffffffffa029e717>] bond_set_rx_mode+0xc7/0xd0 [bonding]
[<ffffffff81553af7>] __dev_set_rx_mode+0x57/0xa0
[<ffffffff81557ff8>] __dev_mc_add+0x58/0x70
[<ffffffff81558020>] dev_mc_add+0x10/0x20
[<ffffffff8161e26e>] igmp6_group_added+0x18e/0x1d0
[<ffffffff81186f76>] ? kmem_cache_alloc_trace+0x236/0x260
[<ffffffff8161f80f>] ipv6_dev_mc_inc+0x29f/0x320
[<ffffffff8161f9e7>] ipv6_sock_mc_join+0x157/0x260
...
Fix this by using RCU primitives.
Reported-by: Joe Lawrence <joe.lawrence@stratus.com>
Tested-by: Joe Lawrence <joe.lawrence@stratus.com>
CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Recently grabbed this report:
https://bugzilla.redhat.com/show_bug.cgi?id=1005567
Of an issue in which the bonding driver, with an attached vlan encountered the
following errors when bond0 was taken down and back up:
dummy1: promiscuity touches roof, set promiscuity failed. promiscuity feature of
device might be broken.
The error occurs because, during __bond_release_one, if we release our last
slave, we take on a random mac address and issue a NETDEV_CHANGEADDR
notification. With an attached vlan, the vlan may see that the vlan and bond
mac address were in sync, but no longer are. This triggers a call to dev_uc_add
and dev_set_rx_mode, which enables IFF_PROMISC on the bond device. Then, when
we complete __bond_release_one, we use the current state of the bond flags to
determine if we should decrement the promiscuity of the releasing slave. But
since the bond changed promiscuity state during the release operation, we
incorrectly decrement the slave promisc count when it wasn't in promiscuous mode
to begin with, causing the above error
Fix is pretty simple, just cache the bonding flags at the start of the function
and use those when determining the need to set promiscuity.
This is also needed for the ALLMULTI flag
CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
CC: Mark Wu <wudxw@linux.vnet.ibm.com>
CC: "David S. Miller" <davem@davemloft.net>
Reported-by: Mark Wu <wudxw@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
It's a forgotten function declaration, which was removed some time ago
already.
CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
There are no users left, so it's safe to remove.
CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We don't need the circular loop there and it's the only current user of
bond_next_slave() - so just use the standard bond_for_each_slave().
CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
It has no users, so it's safe to remove it completely.
CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Convert all instances of
for (agg = __get_first_agg(); agg; agg = __get_next_port)
to the standard bond_for_each_slave().
CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Convert all instances of
for (agg = __get_first_agg(); agg; agg = __get_next_port)
to the standard bond_for_each_slave(). Also, remove the useless checks
before calling bond_3ad_set_carrier() - if we have something NULL - it
would fire long ago, in __get_first/next_port(), per example.
CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently we're relying on suboptimal construct
for (; aggregator; aggregator = __get_next_agg(aggregator)) {
where aggregator is an argument of __get_active_agg() which is _always_ the
first slave's aggregator - judging by all the callers, comments in the
ad_agg_selection_logic() and by logic.
Convert it to use the standard bond_for_each_slave().
CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently, ad_port_selection_logic() uses
for (aggregator = __get_first_agg(port); aggregator;
aggregator = __get_next_agg(aggregator)) {
construct, however it's suboptimal, difficult to read and understand.
Change it to a standard bond_for_each_slave(), so that we won't need
__get_first/next_agg() and have it more readable.
CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently we have only one user of it, so it's kind of useless and just
obfusicates things.
Remove it and move the logic to the only user -
bond_3ad_state_machine_handler().
CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently this function is only used in constructs like
for (port = __get_first_port(bond); port; port = __get_next_port(port))
which is basicly the same as
bond_for_each_slave(bond, slave, iter) {
port = &(SLAVE_AD_INFO(slave).port);
but a more time consuming.
Remove the function and convert the users to bond_for_each_slave().
CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
After commit 1f718f0f4f ("bonding: populate
neighbour's private on enslave"), we've moved the unlinking of the slave
to the earliest position possible - so that nobody will see an
half-uninited slave.
However, bond_3ad_unbind_slave() relied that, even while removing the last
slave, it is still accessible - via __get_first_agg() (and, eventually,
bond_first_slave()).
Fix that by verifying if the aggregator return is an actual aggregator, but
not NULL.
CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
After commit 1f718f0f4f ("bonding: populate
neighbour's private on enslave"), we've moved the actual 'linking' in the
end of the function - so that, once linked, the slave is ready to be used,
and is not still in the process of enslaving.
However, 802.3ad verified if it's the first slave by looking at the
if (bond_first_slave(bond) == new_slave)
which, because we've moved the linking to the end, became broken - on the
first slave bond_first_slave(bond) returns NULL.
Fix this by verifying if the prev_slave, that equals bond_last_slave(), is
actually populated - if it is - then it's not the first slave, and vice
versa.
CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Also, remove the same functionality from bonding - it will be already done
for any device that links to its lower/upper neighbour.
The links will be created for dev's kobject, and will look like
lower_eth0 for lower device eth0 and upper_bridge0 for upper device
bridge0.
CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
CC: "David S. Miller" <davem@davemloft.net>
CC: Eric Dumazet <edumazet@google.com>
CC: Jiri Pirko <jiri@resnulli.us>
CC: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently, we can have only one master upper neighbour, so it would be
useful to create a symlink to it in the sysfs device directory, the way
that bonding now does it, for every device. Lower devices from
bridge/team/etc will automagically get it, so we could rely on it.
Also, remove the same functionality from bonding.
CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
CC: "David S. Miller" <davem@davemloft.net>
CC: Eric Dumazet <edumazet@google.com>
CC: Jiri Pirko <jiri@resnulli.us>
CC: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
And all the initialization.
CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use the new function __bond_next_slave().
CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add a new function, __bond_next_slave(), which uses neighbours to find the
next slave after the slave provided. It will be further used to gradually
go start using neighbour netdev_adjacent infrastructure instead of
bonding's own lists.
CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
CC: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We don't really need it, and it's really hard to RCUify the list->prev.
CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
For that, use netdev_adjacent_get_private(list_head) on bond's lower
neighbour list members. Also, add a small macro - bond_slave_list(bond),
which returns the bond list via neighbour list.
CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The same way as it was used for its own slave_list.
CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently we verify if we have slaves by checking if bond->slave_list is
empty. Create a define bond_has_slaves() and use it, a bit more readable
and easier to change in the future.
CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
It has no users, so we can remove it.
CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently it uses the hard-to-rcuify bond_for_each_slave_from(), and also
it doesn't check every slave for disrepencies between the actual
IS_UP(slave) and the slave->link == BOND_LINK_UP, but only till we find the
next suitable slave.
Fix this by using bond_for_each_slave() and storing the first good slave in
*before till we find the current_arp_slave, after that we store the first good
slave in new_slave. If new_slave is empty - use the slave stored in before,
and if it's also empty - then we didn't find any suitable slave.
Also, in the meanwhile, check for each slave status.
CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
bond_find_best_slave() does not have to be balanced - i.e. return the slave
that is *after* some other slave, but rather return the best slave that
suits, except of bond->primary_slave - in which case we just return it if
it's suitable.
After that we just look through all the slaves and return either first up
slave or the slave whose link came back earliest.
We also don't care about curr_active_slave lock cause we use it in
bond_should_change_active() only and there we take it right away - i.e. it
won't go away.
CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>