Hello Marcin,
On Fri, 9 Dec 2016 15:19:37 +0100
Marcin Nowakowski <marcin.nowakow...@imgtec.com> wrote:
> The number of probe hits is stored in a percpu variable and therefore
> can't be read directly. Add a helper method trace_kprobe_nhit() that
> performs the required calculation.
>
> It will be used in a follow-up commit that changes kprobe selftests to
> verify the number of probe hits.
Ah, that's nicer & neet :)
Acked-by: Masami Hiramatsu <mhira...@kernel.org>
Thanks!
>
> Signed-off-by: Marcin Nowakowski <marcin.nowakow...@imgtec.com>
> ---
> kernel/trace/trace_kprobe.c | 19 +++++++++++++------
> 1 file changed, 13 insertions(+), 6 deletions(-)
>
> v2: improved commit message as suggested by Steven Rostedt
>
> diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
> index eb6c9f1..a2af1bc 100644
> --- a/kernel/trace/trace_kprobe.c
> +++ b/kernel/trace/trace_kprobe.c
> @@ -73,6 +73,17 @@ static nokprobe_inline bool
> trace_kprobe_is_on_module(struct trace_kprobe *tk)
> return !!strchr(trace_kprobe_symbol(tk), ':');
> }
>
> +static nokprobe_inline unsigned long trace_kprobe_nhit(struct trace_kprobe
> *tk)
> +{
> + unsigned long nhit = 0;
> + int cpu;
> +
> + for_each_possible_cpu(cpu)
> + nhit += *per_cpu_ptr(tk->nhit, cpu);
> +
> + return nhit;
> +}
> +
> static int register_kprobe_event(struct trace_kprobe *tk);
> static int unregister_kprobe_event(struct trace_kprobe *tk);
>
> @@ -882,14 +893,10 @@ static const struct file_operations kprobe_events_ops =
> {
> static int probes_profile_seq_show(struct seq_file *m, void *v)
> {
> struct trace_kprobe *tk = v;
> - unsigned long nhit = 0;
> - int cpu;
> -
> - for_each_possible_cpu(cpu)
> - nhit += *per_cpu_ptr(tk->nhit, cpu);
>
> seq_printf(m, " %-44s %15lu %15lu\n",
> - trace_event_name(&tk->tp.call), nhit,
> + trace_event_name(&tk->tp.call),
> + trace_kprobe_nhit(tk),
> tk->rp.kp.nmissed);
>
> return 0;
> --
> 2.7.4
>
--
Masami Hiramatsu <mhira...@kernel.org>
