[PATCH v2 1/5] perf-probe: Add warning message if there is unexpected event name

[Masami Hiramatsu]

This improve the error message so that user can know
event-name error before writing new events to
kprobe-events interface.

E.g.
   ======
   #./perf probe -x /lib64/libc-2.25.so malloc_get_state*
   Internal error: "malloc_get_state@GLIBC_2" is wrong event name.
     Error: Failed to add events.
   ======

Signed-off-by: Masami Hiramatsu <mhira...@kernel.org>
---
 tools/perf/util/probe-event.c |    8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
index b7aaf9b2294d..c0067950e56f 100644
--- a/tools/perf/util/probe-event.c
+++ b/tools/perf/util/probe-event.c
@@ -2625,6 +2625,14 @@ static int get_new_event_name(char *buf, size_t len, 
const char *base,
 
 out:
        free(nbase);
+
+       /* Final validation */
+       if (ret >= 0 && !is_c_func_name(buf)) {
+               pr_warning("Internal error: \"%s\" is wrong event name.\n",
+                          buf);
+               ret = -EINVAL;
+       }
+
        return ret;
 }