On Thu, Mar 10, 2016 at 09:36:37AM +0900, Namhyung Kim wrote: > Hi Jiri, > > On Wed, Mar 09, 2016 at 09:46:41PM +0100, Jiri Olsa wrote: > > Currently we check sample type for ftrace:function event > > even if it's not created as sampling event. That prevents > > creating ftrace_function event in counting mode. > > > > Making sure we check sample types only for sampling events. > > > > Before: > > $ sudo perf stat -e ftrace:function ls > > ... > > > > Performance counter stats for 'ls': > > > > <not supported> ftrace:function > > > > 0.001983662 seconds time elapsed > > > > After: > > $ sudo perf stat -e ftrace:function ls > > ... > > > > Performance counter stats for 'ls': > > > > 44,498 ftrace:function > > > > 0.037534722 seconds time elapsed > > > > Signed-off-by: Jiri Olsa <jo...@kernel.org> > > --- > > kernel/trace/trace_event_perf.c | 4 ++-- > > 1 file changed, 2 insertions(+), 2 deletions(-) > > > > diff --git a/kernel/trace/trace_event_perf.c > > b/kernel/trace/trace_event_perf.c > > index 00df25fd86ef..a7171ec2c1ca 100644 > > --- a/kernel/trace/trace_event_perf.c > > +++ b/kernel/trace/trace_event_perf.c > > @@ -52,14 +52,14 @@ static int perf_trace_event_perm(struct > > trace_event_call *tp_event, > > * event, due to issues with page faults while tracing page > > * fault handler and its overall trickiness nature. > > */ > > - if (!p_event->attr.exclude_callchain_user) > > + if (is_sampling_event(p_event) && > > !p_event->attr.exclude_callchain_user) > > return -EINVAL; > > > > /* > > * Same reason to disable user stack dump as for user space > > * callchains above. > > */ > > - if (p_event->attr.sample_type & PERF_SAMPLE_STACK_USER) > > + if (is_sampling_event(p_event) && p_event->attr.sample_type & > > PERF_SAMPLE_STACK_USER) > > return -EINVAL; > > } > > > > What about checking is_sampling_event() first and goto the last > paranoid_tracepoint_raw check instead? This way we can remove the > same check in the function trace case.
right, will check thanks, jirka
