perf util: Replace strerror with strerror_r for thread-safety

Replaces all strerror with strerror_r in util for making the perf lib
thread-safe.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naohiro Aota <naota@elisp.net>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20140814022236.3545.3367.stgit@kbuild-fedora.novalocal
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
index 1e15df1..e34c81a 100644
--- a/tools/perf/util/parse-events.c
+++ b/tools/perf/util/parse-events.c
@@ -10,6 +10,7 @@
 #include "symbol.h"
 #include "cache.h"
 #include "header.h"
+#include "debug.h"
 #include <api/fs/debugfs.h>
 #include "parse-events-bison.h"
 #define YY_EXTRA_TYPE int
@@ -1006,9 +1007,11 @@
 	struct dirent *sys_next, *evt_next, sys_dirent, evt_dirent;
 	char evt_path[MAXPATHLEN];
 	char dir_path[MAXPATHLEN];
+	char sbuf[STRERR_BUFSIZE];
 
 	if (debugfs_valid_mountpoint(tracing_events_path)) {
-		printf("  [ Tracepoints not available: %s ]\n", strerror(errno));
+		printf("  [ Tracepoints not available: %s ]\n",
+			strerror_r(errno, sbuf, sizeof(sbuf)));
 		return;
 	}