perf trace: Free malloc'd trace fields on exit

ASan reports several memory leaks running:

  # perf test "88: Check open filename arg using perf trace + vfs_getname"

The first of these leaks is related to struct trace fields never being
deallocated.

This patch adds the function trace__exit, which is called at the end of
cmd_trace, replacing the existing deallocation, which is now moved
inside the new function.

This function deallocates:

 - ev_qualifier
 - ev_qualifier_ids.entries
 - syscalls.table
 - sctbl
 - perfconfig_events

Signed-off-by: Riccardo Mancini <rickyman7@gmail.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/de5945ed5c0cb882cbfa3268567d0bff460ff016.1626343282.git.rickyman7@gmail.com
[ Removed needless initialization to zero, missing named initializers are zeroed by the compiler ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/builtin-trace.c

@@ -4701,6 +4701,15 @@ static int trace__config(const char *var, const char *value, void *arg)
 	return err;
 }
 
+static void trace__exit(struct trace *trace)
+{
+	strlist__delete(trace->ev_qualifier);
+	free(trace->ev_qualifier_ids.entries);
+	free(trace->syscalls.table);
+	syscalltbl__delete(trace->sctbl);
+	zfree(&trace->perfconfig_events);
+}
+
 int cmd_trace(int argc, const char **argv)
 {
 	const char *trace_usage[] = {
@@ -5135,6 +5144,6 @@ int cmd_trace(int argc, const char **argv)
 	if (output_name != NULL)
 		fclose(trace.output);
 out:
-	zfree(&trace.perfconfig_events);
+	trace__exit(&trace);
 	return err;
 }