From: Marcin Nowakowski <marcin.nowakow...@imgtec.com>

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.

Link: 
http://lkml.kernel.org/r/1481293178-3128-1-git-send-email-marcin.nowakow...@imgtec.com

Acked-by: Masami Hiramatsu <mhira...@kernel.org>
Signed-off-by: Marcin Nowakowski <marcin.nowakow...@imgtec.com>
Signed-off-by: Steven Rostedt <rost...@goodmis.org>
---
 kernel/trace/trace_kprobe.c | 19 +++++++++++++------
 1 file changed, 13 insertions(+), 6 deletions(-)

diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
index eb6c9f1d3a93..a2af1bceca29 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;
-- 
2.10.2


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