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

From: Jiri Olsa
Date: Fri Mar 11 2016 - 03:39:44 EST


On Thu, Mar 10, 2016 at 09:39:55AM +0900, Namhyung Kim wrote:
> On Wed, Mar 09, 2016 at 09:46:42PM +0100, Jiri Olsa 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?
> >
> > Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
>
> Acked-by: Namhyung Kim <namhyung@xxxxxxxxxx>
>
> Maybe we need to improve the error message later.

yep, working on that ;-)

thanks,
jirka