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| author | Jiri Olsa <jolsa@redhat.com> | 2012-02-15 18:51:52 +0400 |
|---|---|---|
| committer | Steven Rostedt <rostedt@goodmis.org> | 2012-02-21 20:08:27 +0400 |
| commit | ced39002f5ea736b716ae233fb68b26d59783912 (patch) | |
| tree | 4942ffe3b9e26d5122a5febb885d0b541e3aea33 /kernel/trace/trace_export.c | |
| parent | e59a0bff3ecf389951e3c9378ddfd00f6448bfaa (diff) | |
| download | linux-ced39002f5ea736b716ae233fb68b26d59783912.tar.xz | |
ftrace, perf: Add support to use function tracepoint in perf
Adding perf registration support for the ftrace function event,
so it is now possible to register it via perf interface.
The perf_event struct statically contains ftrace_ops as a handle
for function tracer. The function tracer is registered/unregistered
in open/close actions.
To be efficient, we enable/disable ftrace_ops each time the traced
process is scheduled in/out (via TRACE_REG_PERF_(ADD|DELL) handlers).
This way tracing is enabled only when the process is running.
Intentionally using this way instead of the event's hw state
PERF_HES_STOPPED, which would not disable the ftrace_ops.
It is now possible to use function trace within perf commands
like:
perf record -e ftrace:function ls
perf stat -e ftrace:function ls
Allowed only for root.
Link: http://lkml.kernel.org/r/1329317514-8131-6-git-send-email-jolsa@redhat.com
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Diffstat (limited to 'kernel/trace/trace_export.c')
| -rw-r--r-- | kernel/trace/trace_export.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/kernel/trace/trace_export.c b/kernel/trace/trace_export.c index f74de861cde9..a3dbee6d04cd 100644 --- a/kernel/trace/trace_export.c +++ b/kernel/trace/trace_export.c @@ -184,4 +184,9 @@ __attribute__((section("_ftrace_events"))) *__event_##call = &event_##call; FTRACE_ENTRY_REG(call, struct_name, etype, \ PARAMS(tstruct), PARAMS(print), NULL) +int ftrace_event_is_function(struct ftrace_event_call *call) +{ + return call == &event_function; +} + #include "trace_entries.h" |