Re: [PATCH 2/5] ftrace perf: Move exclude_kernel tracepoint check to init event

Steven Rostedt
2016-03-18T14:28:19Z

On Wed, 16 Mar 2016 15:34:30 +0100
Jiri Olsa <jolsa@kernel.org> wrote:

> We suppress events with attr::exclude_kernel set when
> the event is generated, so following capture will
> give no warning but won't produce any data:
>
> $ sudo perf record -e sched:sched_switch:u ls
> $ sudo /perf script | wc -l
> 0
>
> Checking the attr::exclude_(kernel|user) at the event
> init time and failing right away for tracepoints from
> uprobes/kprobes and native ones:
>
> $ sudo perf record -e sched:sched_switch:u ls
> Error:
> The sys_perf_event_open() syscall returned with 22 (Invalid argument) for event (sched:sched_switch).
> /bin/dmesg may provide additional information.
> No CONFIG_PERF_EVENTS=y kernel support configured?
>
> $ sudo perf record -e probe:sys_read:u ls
> Error:
> The sys_perf_event_open() syscall returned with 22 (Invalid argument) for event (probe:sys_read).
> /bin/dmesg may provide additional information.
> No CONFIG_PERF_EVENTS=y kernel support configured?
>
> $ ./perf record -e probe_ex:main:k ./ex
> Error:
> The sys_perf_event_open() syscall returned with 22 (Invalid argument) for event (probe_ex:main).
> /bin/dmesg may provide additional information.
> No CONFIG_PERF_EVENTS=y kernel support configured?
>
> Acked-by: Namhyung Kim <namhyung@kernel.org>
> Signed-off-by: Jiri Olsa <jolsa@kernel.org>

Acked-by: Steven Rostedt <rostedt@goodmis.org>

-- Steve