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| author | Tom Zanussi <tom.zanussi@linux.intel.com> | 2013-10-24 17:59:25 +0400 |
|---|---|---|
| committer | Steven Rostedt <rostedt@goodmis.org> | 2013-12-21 03:40:24 +0400 |
| commit | 2a2df321158817811c5dc206dce808e0aa9f6d89 (patch) | |
| tree | fd93466f3bf01a224e55f488eb199befb382beca /include/linux | |
| parent | 85f2b08268c014e290b600ba49fa85530600eaa1 (diff) | |
| download | linux-2a2df321158817811c5dc206dce808e0aa9f6d89.tar.xz | |
tracing: Add 'traceon' and 'traceoff' event trigger commands
Add 'traceon' and 'traceoff' event_command commands. traceon and
traceoff event triggers are added by the user via these commands in a
similar way and using practically the same syntax as the analagous
'traceon' and 'traceoff' ftrace function commands, but instead of
writing to the set_ftrace_filter file, the traceon and traceoff
triggers are written to the per-event 'trigger' files:
echo 'traceon' > .../tracing/events/somesys/someevent/trigger
echo 'traceoff' > .../tracing/events/somesys/someevent/trigger
The above command will turn tracing on or off whenever someevent is
hit.
This also adds a 'count' version that limits the number of times the
command will be invoked:
echo 'traceon:N' > .../tracing/events/somesys/someevent/trigger
echo 'traceoff:N' > .../tracing/events/somesys/someevent/trigger
Where N is the number of times the command will be invoked.
The above commands will will turn tracing on or off whenever someevent
is hit, but only N times.
Some common register/unregister_trigger() implementations of the
event_command reg()/unreg() callbacks are also provided, which add and
remove trigger instances to the per-event list of triggers, and
arm/disarm them as appropriate. event_trigger_callback() is a
general-purpose event_command func() implementation that orchestrates
command parsing and registration for most normal commands.
Most event commands will use these, but some will override and
possibly reuse them.
The event_trigger_init(), event_trigger_free(), and
event_trigger_print() functions are meant to be common implementations
of the event_trigger_ops init(), free(), and print() ops,
respectively.
Most trigger_ops implementations will use these, but some will
override and possibly reuse them.
Link: http://lkml.kernel.org/r/00a52816703b98d2072947478dd6e2d70cde5197.1382622043.git.tom.zanussi@linux.intel.com
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/ftrace_event.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/include/linux/ftrace_event.h b/include/linux/ftrace_event.h index 211e7ad2baf5..711c4dcfe8b7 100644 --- a/include/linux/ftrace_event.h +++ b/include/linux/ftrace_event.h @@ -345,6 +345,7 @@ struct ftrace_event_file { enum event_trigger_type { ETT_NONE = (0), + ETT_TRACE_ONOFF = (1 << 0), }; extern void destroy_preds(struct ftrace_event_file *file); |