The major changes are in the flow offload firmware APIs.
Signed-off-by: NMichael Chan <michael.chan@broadcom.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Steffen Klassert says:

====================
pull request (net-next): ipsec-next 2018-12-20

Two last patches for this release cycle:

1) Remove an unused variable in xfrm_policy_lookup_bytype().
   From YueHaibing.

2) Fix possible infinite loop in __xfrm6_tunnel_alloc_spi().
   Also from YueHaibing.

Please pull or let me know if there are problems.
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add NDA_PROTOCOL to nda_policy and use the policy for attribute parsing and
validation for adding neighbors and in dump requests. Remove the now duplicate
checks on nla_len.
Signed-off-by: NDavid Ahern <dsahern@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Peng Li says:

====================
net: hns3: code optimizations & bugfixes for HNS3 driver

This patchset includes bugfixes and code optimizations for the HNS3
ethernet controller driver
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch removes the redundant variable initialization,
as driver will devm_kzalloc to set value to hdev soon.
Signed-off-by: NPeng Li <lipeng321@huawei.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Driver gets rss information from the last descriptor of the packet.
When driver handle the rss type, ring->next_to_clean indicates the
first descriptor of next packet.

This patch fix the descriptor index with "ring->next_to_clean - 1".

Fixes: 232fc64b ("net: hns3: Add HW RSS hash information to RX skb")
Signed-off-by: NPeng Li <lipeng321@huawei.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When user disables flow director, all the rules will be disabled. But
when reset happens, it will restore all the rules again. It's not
reasonable. This patch fixes it by add flow director status check before
restore fules.

Fixes: 6871af29 ("net: hns3: Add reset handle for flow director")
Fixes: c17852a8 ("net: hns3: Add support for enable/disable flow director")
Signed-off-by: NJian Shen <shenjian15@huawei.com>
Signed-off-by: NPeng Li <lipeng321@huawei.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When add flow director fule for vf, the vf id is used as array
subscript before valid checking, which may cause memory overflow.

Fixes: dd74f815 ("net: hns3: Add support for rule add/delete for flow director")
Signed-off-by: NJian Shen <shenjian15@huawei.com>
Signed-off-by: NPeng Li <lipeng321@huawei.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

While doing DOWN operation, the driver will reclaim the memory which has
already used for TX. If the hardware is processing this memory, it will
cause a RCB error to the hardware. According the hardware's description,
the driver should reset the tqp before reclaim the memory during DOWN.
Signed-off-by: NHuazhong Tan <tanhuazhong@huawei.com>
Signed-off-by: NPeng Li <lipeng321@huawei.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Each pf supports max 64 vectors and 128 tqps. For 2p/4p core scenario,
there may be more than 64 cpus online. So the result of min_t(u16,
num_Online_cpus(), tqp_num) may be more than 64. This patch adds check
for the vector number.

Fixes: dd38c726 ("net: hns3: fix for coalesce configuration lost during reset")
Signed-off-by: NJian Shen <shenjian15@huawei.com>
Signed-off-by: NPeng Li <lipeng321@huawei.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

udelay() in driver may always occupancy processor. If there is only
one cpu in system, the VF driver may initialize fail when insmod
PF and VF driver in the same system. This patch use msleep() to free
cpu when VF wait PF message.
Signed-off-by: NPeng Li <lipeng321@huawei.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In original codes, default tc value is set to the max tc. It's more
reasonable to close tc by changing default tc value to 1. Users can
enable it with lldp tool when they want to use tc.
Signed-off-by: NJian Shen <shenjian15@huawei.com>
Signed-off-by: NPeng Li <lipeng321@huawei.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When triggering nic down, there is a time window between bringing down
the protocol stack and stopping the work task. If the net is up in the
time window, it may bring up the protocol stack again.

This patch fixes it by stop the work task at the beginning of
hns3_nic_net_stop(). To keep symmetrical, start the work task at the
end of hns3_nic_net_open().
Signed-off-by: NJian Shen <shenjian15@huawei.com>
Signed-off-by: NPeng Li <lipeng321@huawei.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

pneigh_lookup uses kmalloc versus kzalloc when new entries are allocated.
Given that the newly added protocol field needs to be initialized.

Fixes: df9b0e30 ("neighbor: Add protocol attribute")
Signed-off-by: NDavid Ahern <dsahern@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch refactors reuseport_add_any selftest a bit:
- makes it more modular (eliminates several copy/pasted blocks);
- skips DCCP tests if DCCP is not supported

V2: added "Signed-off-by" tag.
Signed-off-by: NPeter Oskolkov <posk@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The 6320 family of switches uses the same watchdog registers as the
6390.
Signed-off-by: NAndrew Lunn <andrew@lunn.ch>
Reviewed-by: NVivien Didelot <vivien.didelot@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Biao Huang says:

====================
add ethernet binding and modify ethernet driver for mt2712

changes in v3:
resend this series base on the latest net-next tree.

changes in v2 as comments from Sean:
1. fix typo.
2. use capital letters for RMII/MII/RGMII in driver and bindings.

v1:
This new series is the result of discussion in:
http://lkml.org/lkml/2018/12/13/1007
http://lkml.org/lkml/2018/12/14/53

1. ethernet binding file move to this series.
2. remove fine tune property in device tree
3. remove fine tune flow in ethernet driver
4. set rgmii timing according to the value in device tree,
and don't care whether phy insert internal delay  or not.
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

1. remove fine-tune property and related setting to simplify
the timing adjustment flow.
2. set timing value according to the value from device tree,
and will not care whether PHY insert internal delay.
Signed-off-by: NBiao Huang <biao.huang@mediatek.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

remove fine-tune property in device tree, modify
the corresponding description in dt-binding.
Signed-off-by: NBiao Huang <biao.huang@mediatek.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Roopa Prabhu says:

====================
neigh get support

This series adds support for neigh get similar
to route and recently added fdb get.

v2: fix key len check. and some other fixes
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NRoopa Prabhu <roopa@cumulusnetworks.com>
Reviewed-by: NDavid Ahern <dsa@cumulusnetworks.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

this patch registers neigh doit handler. The doit handler
returns a neigh entry given dst and dev. This is similar
to route and fdb doit (get) handlers. Also moves nda_policy
declaration from rtnetlink.c to neighbour.c
Signed-off-by: NRoopa Prabhu <roopa@cumulusnetworks.com>
Reviewed-by: NDavid Ahern <dsa@cumulusnetworks.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Ido Schimmel says:

====================
mlxsw: Make driver more robust

In recent months we fixed several bugs in the driver that could have
been avoided by re-evaluating some of the involved code paths and by
introducing relevant and comprehensive test cases.

This patchset tries to do that by introducing a set of small and mostly
non-functional changes in addition to a new test. I have further
improvements in mind, but they can be done in a different set.

Patch #1 makes sure we correctly sanitize upper devices of a VLAN
interface.

Patch #2 removes an unexpected behavior from the driver, in which routes
configured on a VLAN interface will cease being offloaded after certain
operations.

Patch #3 is a small cleanup.

Patch #4 simplifies the driver by removing reference counting from VLAN
entries configured on a port.

Patches #5-#6 simplify linking/unlinking from a bridge, especially when
LAG and VLAN devices are involved. They make both operations symmetric
even when ports are unlinked from a bridged LAG device.

Patch #7-#9 make router interface (RIF) deletion more robust by removing
reliance on device chain to indicate whether a NETDEV_DOWN event in the
inet{,6}addr notification chains should be processed. This is due to the
fact that IP addresses can be flushed from a netdev after it was
unlinked from its lower device.

Patch #10 adds a new test to for valid and invalid configurations over
mlxsw ports. Some of the test cases are derived from recent fixes. I
expect that more test cases will be added over time.
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add a new test that is focused on rtnetlink configuration. Its purpose
is to test valid and invalid (as deemed by mlxsw) configurations and
make sure that they succeed / fail without producing a trace.

Some of the test cases are derived from recent fixes in order to make
sure that the fixed bugs are not introduced again.
Signed-off-by: NIdo Schimmel <idosch@mellanox.com>
Reviewed-by: NPetr Machata <petrm@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Previous patches tried to make RIF deletion more robust and avoid
use-after-free situations.

As another precaution, hold a reference on a RIF's netdev and release it
when the RIF is deleted.
Signed-off-by: NIdo Schimmel <idosch@mellanox.com>
Reviewed-by: NPetr Machata <petrm@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In the past we had multiple instances where RIFs were not properly
deleted.

One of the reasons for leaking a RIF was that at the time when IP
addresses were flushed from the respective netdev (prompting the
destruction of the RIF), the netdev was no longer a mlxsw upper. This
caused the inet{,6}addr notification blocks to ignore the NETDEV_DOWN
event and leak the RIF.

Instead of checking whether the netdev is our upper when an IP address
is removed, we can instead check if the netdev has a RIF configured.

To look up a RIF we need to access mlxsw private data, so the patch
stores the notification blocks inside a mlxsw struct. This then allows
us to use container_of() and extract the required private data.
Signed-off-by: NIdo Schimmel <idosch@mellanox.com>
Reviewed-by: NPetr Machata <petrm@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Next patch is going to make RIF deletion more robust by removing
reliance on fragile mlxsw_sp_lower_get(). This is because a netdev is
not necessarily our upper anymore when its IP addresses are flushed.

The inet{,6}addr notification blocks are going to resolve 'struct
mlxsw_sp' using container_of(), but the functions they call still use
mlxsw_sp_lower_get().

As a preparation for the next patch, propagate 'struct mlxsw_sp' down to
the functions called from the notification blocks and remove reliance on
mlxsw_sp_lower_get().
Signed-off-by: NIdo Schimmel <idosch@mellanox.com>
Reviewed-by: NPetr Machata <petrm@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When a LAG device or a VLAN device on top of it is enslaved to a bridge,
the driver propagates the CHANGEUPPER event to the LAG's slaves.

This causes each physical port to increase the reference count of the
internal representation of the bridge port by calling
mlxsw_sp_port_bridge_join().

However, when a port is removed from a LAG, the corresponding leave()
function is not called and the reference count is not decremented. This
leads to ugly hacks such as mlxsw_sp_bridge_port_should_destroy() that
try to understand if the bridge port should be destroyed even when its
reference count is not 0.

Instead, make sure that when a port is unlinked from a LAG it would see
the same events as if the LAG (or its uppers) were unlinked from a
bridge.

The above is achieved by walking the LAG's uppers when a port is
unlinked and calling mlxsw_sp_port_bridge_leave() for each upper that is
enslaved to a bridge.
Signed-off-by: NIdo Schimmel <idosch@mellanox.com>
Reviewed-by: NPetr Machata <petrm@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit b3529af6 ("spectrum: Reference count VLAN entries") started
reference counting port-VLAN entries in a similar fashion to the 8021q
driver.

However, this is not actually needed and only complicates things.
Instead, the driver should forbid the creation of a VLAN on a port if
this VLAN already exists. This would also solve the issue fixed by the
mentioned commit.

Therefore, remove the get()/put() API and use create()/destroy()
instead.

One place that needs special attention is VLAN addition in a VLAN-aware
bridge via switchdev operations. In case the VLAN flags (e.g., 'pvid')
are toggled, then the VLAN entry already exists. To prevent the driver
from wrongly returning EEXIST, the driver is changed to check in the
prepare phase whether the entry already exists and only returns an error
in case it is not associated with the correct bridge port.
Signed-off-by: NIdo Schimmel <idosch@mellanox.com>
Reviewed-by: NPetr Machata <petrm@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In commit 993107fe ("mlxsw: spectrum_switchdev: Fix VLAN device
deletion via ioctl") I fixed a bug caused by the fact that the driver
views differently the deletion of a VLAN device when it is deleted via
an ioctl and netlink.

Instead of relying on a specific order of events (device being
unregistered vs. VLAN filter being updated), simply make sure that the
driver performs the necessary cleanup when the VLAN device is unlinked,
which always happens before the other two events.
Signed-off-by: NIdo Schimmel <idosch@mellanox.com>
Reviewed-by: NPetr Machata <petrm@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This function is no longer used. Remove it.
Signed-off-by: NIdo Schimmel <idosch@mellanox.com>
Reviewed-by: NPetr Machata <petrm@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Currently, when a RIF is constructed on top of a FID, the RIF increments
the FID's reference count and the RIF is destroyed when the FID's
reference count drops to 1. This effectively means that when no local
ports are member in the FID, the FID is destroyed regardless if the
router port is a member in the FID or not.

The above can lead to the unexpected behavior in which routes using a
VLAN interface as their nexthop device are no longer offloaded after the
last local port leaves the corresponding VLAN (FID).

Example:
# ip -4 route show dev br0.10
192.0.2.0/24 proto kernel scope link src 192.0.2.1 offload
# bridge vlan del vid 10 dev swp3
# ip -4 route show dev br0.10
192.0.2.0/24 proto kernel scope link src 192.0.2.1

After the patch, the route is offloaded before and after the VLAN is
removed from local port 'swp3', as the RIF corresponding to 'br0.10'
continues to exists.

In order to remove RIFs' reliance on the underlying FID's reference
count, we need to add a reference count to sub-port RIFs, which are RIFs
that correspond to physical ports and their uppers (e.g., LAG devices).

In this case, each {Port, VID} ('struct mlxsw_sp_port_vlan') needs to
hold a reference on the RIF. For example:

                       bond0.10
                          |
                        bond0
                          |
                      +-------+
                      |       |
                    swp1    swp2

Both {Port 1, VID 10} and {Port 2, VID 10} will hold a reference on the
RIF corresponding to 'bond0.10'. When the last reference is dropped, the
RIF will be destroyed.
Signed-off-by: NIdo Schimmel <idosch@mellanox.com>
Reviewed-by: NPetr Machata <petrm@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Currently, only VRF and macvlan uppers are supported on top of VLAN
device configured over a bridge, so make sure the driver forbids other
uppers.

Note that enslavement to a VRF is handled earlier in the notification
block, so there is no need to check for a VRF upper here.
Signed-off-by: NIdo Schimmel <idosch@mellanox.com>
Reviewed-by: NPetr Machata <petrm@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When sending broadcast message on high load system, there are a lot of
unnecessary packets restranmission. That issue was caused by missing in
initial criteria for retransmission.

To prevent this happen, just initialize this criteria for retransmission
in next 10 milliseconds.

Fixes: 31c4f4cc ("tipc: improve broadcast retransmission algorithm")
Acked-by: NYing Xue <ying.xue@windriver.com>
Acked-by: NJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NHoang Le <hoang.h.le@dektech.com.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Tuong Lien says:

====================
tipc: tracepoints and trace_events in TIPC

The patch series is the first step of introducing a tracing framework in
TIPC, which will assist in collecting complete & plentiful data for post
analysis, even in the case of a single failure occurrence e.g. when the
failure is unreproducible.

The tracing code in TIPC utilizes the powerful kernel tracepoints, trace
events features along with particular dump functions to trace the TIPC
object data and events (incl. bearer, link, socket, node, etc.).

The tracing code should generate zero-load to TIPC when the trace events
are not enabled.
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The commit adds the new trace_event for TIPC bearer, L2 device event:

trace_tipc_l2_device_event()

Also, it puts the trace at the tipc_l2_device_event() function, then
the device/bearer events and related info can be traced out during
runtime when needed.
Acked-by: NYing Xue <ying.xue@windriver.com>
Tested-by: NYing Xue <ying.xue@windriver.com>
Acked-by: NJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NTuong Lien <tuong.t.lien@dektech.com.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The commit adds the new trace_events for TIPC node object:

trace_tipc_node_create()
trace_tipc_node_delete()
trace_tipc_node_lost_contact()
trace_tipc_node_timeout()
trace_tipc_node_link_up()
trace_tipc_node_link_down()
trace_tipc_node_reset_links()
trace_tipc_node_fsm_evt()
trace_tipc_node_check_state()

Also, enables the traces for the following cases:
- When a node is created/deleted;
- When a node contact is lost;
- When a node timer is timed out;
- When a node link is up/down;
- When all node links are reset;
- When node state is changed;
- When a skb comes and node state needs to be checked/updated.
Acked-by: NYing Xue <ying.xue@windriver.com>
Tested-by: NYing Xue <ying.xue@windriver.com>
Acked-by: NJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NTuong Lien <tuong.t.lien@dektech.com.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The commit adds the new trace_events for TIPC socket object:

trace_tipc_sk_create()
trace_tipc_sk_poll()
trace_tipc_sk_sendmsg()
trace_tipc_sk_sendmcast()
trace_tipc_sk_sendstream()
trace_tipc_sk_filter_rcv()
trace_tipc_sk_advance_rx()
trace_tipc_sk_rej_msg()
trace_tipc_sk_drop_msg()
trace_tipc_sk_release()
trace_tipc_sk_shutdown()
trace_tipc_sk_overlimit1()
trace_tipc_sk_overlimit2()

Also, enables the traces for the following cases:
- When user creates a TIPC socket;
- When user calls poll() on TIPC socket;
- When user sends a dgram/mcast/stream message.
- When a message is put into the socket 'sk_receive_queue';
- When a message is released from the socket 'sk_receive_queue';
- When a message is rejected (e.g. due to no port, invalid, etc.);
- When a message is dropped (e.g. due to wrong message type);
- When socket is released;
- When socket is shutdown;
- When socket rcvq's allocation is overlimit (> 90%);
- When socket rcvq + bklq's allocation is overlimit (> 90%);
- When the 'TIPC_ERR_OVERLOAD/2' issue happens;

Note:
a) All the socket traces are designed to be able to trace on a specific
socket by either using the 'event filtering' feature on a known socket
'portid' value or the sysctl file:

/proc/sys/net/tipc/sk_filter

The file determines a 'tuple' for what socket should be traced:

(portid, sock type, name type, name lower, name upper)

where:
+ 'portid' is the socket portid generated at socket creating, can be
found in the trace outputs or the 'tipc socket list' command printouts;
+ 'sock type' is the socket type (1 = SOCK_TREAM, ...);
+ 'name type', 'name lower' and 'name upper' are the service name being
connected to or published by the socket.

Value '0' means 'ANY', the default tuple value is (0, 0, 0, 0, 0) i.e.
the traces happen for every sockets with no filter.

b) The 'tipc_sk_overlimit1/2' event is also a conditional trace_event
which happens when the socket receive queue (and backlog queue) is
about to be overloaded, when the queue allocation is > 90%. Then, when
the trace is enabled, the last skbs leading to the TIPC_ERR_OVERLOAD/2
issue can be traced.

The trace event is designed as an 'upper watermark' notification that
the other traces (e.g. 'tipc_sk_advance_rx' vs 'tipc_sk_filter_rcv') or
actions can be triggerred in the meanwhile to see what is going on with
the socket queue.

In addition, the 'trace_tipc_sk_dump()' is also placed at the
'TIPC_ERR_OVERLOAD/2' case, so the socket and last skb can be dumped
for post-analysis.
Acked-by: NYing Xue <ying.xue@windriver.com>
Tested-by: NYing Xue <ying.xue@windriver.com>
Acked-by: NJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NTuong Lien <tuong.t.lien@dektech.com.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The commit adds the new trace_events for TIPC link object:

trace_tipc_link_timeout()
trace_tipc_link_fsm()
trace_tipc_link_reset()
trace_tipc_link_too_silent()
trace_tipc_link_retrans()
trace_tipc_link_bc_ack()
trace_tipc_link_conges()

And the traces for PROTOCOL messages at building and receiving:

trace_tipc_proto_build()
trace_tipc_proto_rcv()

Note:
a) The 'tipc_link_too_silent' event will only happen when the
'silent_intv_cnt' is about to reach the 'abort_limit' value (and the
event is enabled). The benefit for this kind of event is that we can
get an early indication about TIPC link loss issue due to timeout, then
can do some necessary actions for troubleshooting.

For example: To trigger the 'tipc_proto_rcv' when the 'too_silent'
event occurs:

echo 'enable_event:tipc:tipc_proto_rcv' > \
      events/tipc/tipc_link_too_silent/trigger

And disable it when TIPC link is reset:

echo 'disable_event:tipc:tipc_proto_rcv' > \
      events/tipc/tipc_link_reset/trigger

b) The 'tipc_link_retrans' or 'tipc_link_bc_ack' event is useful to
trace TIPC retransmission issues.

In addition, the commit adds the 'trace_tipc_list/link_dump()' at the
'retransmission failure' case. Then, if the issue occurs, the link
'transmq' along with the link data can be dumped for post-analysis.
These dump events should be enabled by default since it will only take
effect when the failure happens.

The same approach is also applied for the faulty case that the
validation of protocol message is failed.
Acked-by: NYing Xue <ying.xue@windriver.com>
Tested-by: NYing Xue <ying.xue@windriver.com>
Acked-by: NJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NTuong Lien <tuong.t.lien@dektech.com.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

As for the sake of debugging/tracing, the commit enables tracepoints in
TIPC along with some general trace_events as shown below. It also
defines some 'tipc_*_dump()' functions that allow to dump TIPC object
data whenever needed, that is, for general debug purposes, ie. not just
for the trace_events.

The following trace_events are now available:

- trace_tipc_skb_dump(): allows to trace and dump TIPC msg & skb data,
  e.g. message type, user, droppable, skb truesize, cloned skb, etc.

- trace_tipc_list_dump(): allows to trace and dump any TIPC buffers or
  queues, e.g. TIPC link transmq, socket receive queue, etc.

- trace_tipc_sk_dump(): allows to trace and dump TIPC socket data, e.g.
  sk state, sk type, connection type, rmem_alloc, socket queues, etc.

- trace_tipc_link_dump(): allows to trace and dump TIPC link data, e.g.
  link state, silent_intv_cnt, gap, bc_gap, link queues, etc.

- trace_tipc_node_dump(): allows to trace and dump TIPC node data, e.g.
  node state, active links, capabilities, link entries, etc.

How to use:
Put the trace functions at any places where we want to dump TIPC data
or events.

Note:
a) The dump functions will generate raw data only, that is, to offload
the trace event's processing, it can require a tool or script to parse
the data but this should be simple.

b) The trace_tipc_*_dump() should be reserved for a failure cases only
(e.g. the retransmission failure case) or where we do not expect to
happen too often, then we can consider enabling these events by default
since they will almost not take any effects under normal conditions,
but once the rare condition or failure occurs, we get the dumped data
fully for post-analysis.

For other trace purposes, we can reuse these trace classes as template
but different events.

c) A trace_event is only effective when we enable it. To enable the
TIPC trace_events, echo 1 to 'enable' files in the events/tipc/
directory in the 'debugfs' file system. Normally, they are located at:

/sys/kernel/debug/tracing/events/tipc/

For example:

To enable the tipc_link_dump event:

echo 1 > /sys/kernel/debug/tracing/events/tipc/tipc_link_dump/enable

To enable all the TIPC trace_events:

echo 1 > /sys/kernel/debug/tracing/events/tipc/enable

To collect the trace data:

cat trace

or

cat trace_pipe > /trace.out &

To disable all the TIPC trace_events:

echo 0 > /sys/kernel/debug/tracing/events/tipc/enable

To clear the trace buffer:

echo > trace

d) Like the other trace_events, the feature like 'filter' or 'trigger'
is also usable for the tipc trace_events.
For more details, have a look at:

Documentation/trace/ftrace.txt

MAINTAINERS | add two new files 'trace.h' & 'trace.c' in tipc
Acked-by: NYing Xue <ying.xue@windriver.com>
Tested-by: NYing Xue <ying.xue@windriver.com>
Acked-by: NJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NTuong Lien <tuong.t.lien@dektech.com.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>