[PATCH 10/18] perf trace: Provide libtracevent with a kernel symbol resolver

[Arnaldo Carvalho de Melo <acme@kernel.org>]

From: Arnaldo Carvalho de Melo <acme@redhat.com>

So that beautifiers wanting to resolve kernel function addresses to
names can do its work, now, for instance, the 'timer' tracepoints
beautifiers works with 'perf trace', see the "function=tick..." part:

 # perf trace --event timer:hrtimer_start
<SNIP>
  0.000 timer:hrtimer_start:hrtimer=0xffff88026f3101c0 function=tick_sched_timer/0x0 expires=52098339000000 softexpires=52098339000000)
  0.003 timer:hrtimer_start:hrtimer=0xffff88026f3101c0 function=tick_sched_timer/0x0 expires=52098339000000 softexpires=52098339000000)
<SNIP>

Reported-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: David Ahern <dsahern@gmail.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/n/tip-n4i0hxpbl1tnleiqkok47fw2@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/builtin-trace.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c
index 32b4d280af4f..282841b10f24 100644
--- a/tools/perf/builtin-trace.c
+++ b/tools/perf/builtin-trace.c
@@ -1489,6 +1489,9 @@ static int trace__symbols_init(struct trace *trace, struct perf_evlist *evlist)
 	if (trace->host == NULL)
 		return -ENOMEM;
 
+	if (trace_event__register_resolver(trace->host) < 0)
+		return -errno;
+
 	err = __machine__synthesize_threads(trace->host, &trace->tool, &trace->opts.target,
 					    evlist->threads, trace__tool_process, false,
 					    trace->opts.proc_map_timeout);
-- 
2.1.0