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| author | Jiri Olsa <jolsa@redhat.com> | 2012-02-15 15:51:52 +0100 |
|---|---|---|
| committer | Steven Rostedt <rostedt@goodmis.org> | 2012-02-21 11:08:27 -0500 |
| commit | ced39002f5ea736b716ae233fb68b26d59783912 (patch) | |
| tree | 4942ffe3b9e26d5122a5febb885d0b541e3aea33 /kernel/trace/trace.h | |
| parent | e59a0bff3ecf389951e3c9378ddfd00f6448bfaa (diff) | |
| download | linux-ced39002f5ea736b716ae233fb68b26d59783912.tar.gz linux-ced39002f5ea736b716ae233fb68b26d59783912.tar.bz2 linux-ced39002f5ea736b716ae233fb68b26d59783912.zip | |
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.h')
| -rw-r--r-- | kernel/trace/trace.h | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index 638476af8d7b..76a1c5094bbf 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -595,6 +595,8 @@ static inline int ftrace_trace_task(struct task_struct *task) static inline int ftrace_is_dead(void) { return 0; } #endif +int ftrace_event_is_function(struct ftrace_event_call *call); + /* * struct trace_parser - servers for reading the user input separated by spaces * @cont: set if the input is not complete - no final space char was found @@ -832,4 +834,13 @@ extern const char *__stop___trace_bprintk_fmt[]; FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print)) #include "trace_entries.h" +#ifdef CONFIG_PERF_EVENTS +#ifdef CONFIG_FUNCTION_TRACER +int perf_ftrace_event_register(struct ftrace_event_call *call, + enum trace_reg type, void *data); +#else +#define perf_ftrace_event_register NULL +#endif /* CONFIG_FUNCTION_TRACER */ +#endif /* CONFIG_PERF_EVENTS */ + #endif /* _LINUX_KERNEL_TRACE_H */ |