perf tools: Make test use the preset debugfs path

Use preset debugfs path instead of hardcoded one.

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Cc: acme@redhat.com
Cc: a.p.zijlstra@chello.nl
Cc: paulus@samba.org
Link: http://lkml.kernel.org/r/1310635534-4013-4-git-send-email-jolsa@redhat.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>

tools/perf/builtin-test.c

@@ -246,8 +246,8 @@ static int trace_event__id(const char *evname)
 	int err = -1, fd;
 
 	if (asprintf(&filename,
-		     "/sys/kernel/debug/tracing/events/syscalls/%s/id",
-		     evname) < 0)
+		     "%s/syscalls/%s/id",
+		     debugfs_path, evname) < 0)
 		return -1;
 
 	fd = open(filename, O_RDONLY);