linux/net/tipc
Tuong Lien b4b9771bcb tipc: enable tracepoints in tipc
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: Ying Xue <ying.xue@windriver.com>
Tested-by: Ying Xue <ying.xue@windriver.com>
Acked-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Tuong Lien <tuong.t.lien@dektech.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-12-19 11:49:24 -08:00
..
addr.c
addr.h
bcast.c tipc: correct spelling errors for struct tipc_bc_base's comment 2018-09-03 22:03:07 -07:00
bcast.h
bearer.c tipc: enable tracepoints in tipc 2018-12-19 11:49:24 -08:00
bearer.h tipc: enable tracepoints in tipc 2018-12-19 11:49:24 -08:00
core.c
core.h
diag.c tipc: switch to rhashtable iterator 2018-08-29 18:04:54 -07:00
discover.c tipc: fix lockdep warning when reinitilaizing sockets 2018-11-17 22:01:31 -08:00
discover.h
eth_media.c
group.c tipc: fix info leak from kernel tipc_event 2018-10-18 16:49:53 -07:00
group.h
ib_media.c
Kconfig
link.c tipc: enable tracepoints in tipc 2018-12-19 11:49:24 -08:00
link.h tipc: enable tracepoints in tipc 2018-12-19 11:49:24 -08:00
Makefile tipc: enable tracepoints in tipc 2018-12-19 11:49:24 -08:00
monitor.c tipc: make some functions static 2018-07-21 16:23:22 -07:00
monitor.h
msg.c tipc: buffer overflow handling in listener socket 2018-09-29 11:24:22 -07:00
msg.h tipc: improve broadcast retransmission algorithm 2018-11-11 09:57:46 -08:00
name_distr.c tipc: eliminate message disordering during binding table update 2018-10-22 19:29:12 -07:00
name_distr.h
name_table.c tipc: eliminate message disordering during binding table update 2018-10-22 19:29:12 -07:00
name_table.h tipc: eliminate message disordering during binding table update 2018-10-22 19:29:12 -07:00
net.c tipc: fix lockdep warning when reinitilaizing sockets 2018-11-17 22:01:31 -08:00
net.h tipc: fix lockdep warning when reinitilaizing sockets 2018-11-17 22:01:31 -08:00
netlink_compat.c tipc: check return value of __tipc_dump_start() 2018-09-12 13:15:04 -07:00
netlink.c tipc: switch to rhashtable iterator 2018-08-29 18:04:54 -07:00
netlink.h
node.c tipc: enable tracepoints in tipc 2018-12-19 11:49:24 -08:00
node.h tipc: enable tracepoints in tipc 2018-12-19 11:49:24 -08:00
socket.c tipc: enable tracepoints in tipc 2018-12-19 11:49:24 -08:00
socket.h tipc: enable tracepoints in tipc 2018-12-19 11:49:24 -08:00
subscr.c
subscr.h
sysctl.c
topsrv.c Merge branch 'work.afs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2018-11-01 19:58:52 -07:00
topsrv.h
trace.c tipc: enable tracepoints in tipc 2018-12-19 11:49:24 -08:00
trace.h tipc: enable tracepoints in tipc 2018-12-19 11:49:24 -08:00
udp_media.c tipc: support binding to specific ip address when activating UDP bearer 2018-10-15 21:56:56 -07:00
udp_media.h