mds: function parameter 'df' should be passed by reference

Signed-off-by: Na Xie <xie.na@h3c.com>

diff --git a/src/mds/mdstypes.h b/src/mds/mdstypes.h
index 4e1b926d555836d99930e3fb3fc4384cab1dadb7..ab6e488274f2d1be8f864e25e0ea0326a3547fe3 100644 (file)
--- a/src/mds/mdstypes.h
+++ b/src/mds/mdstypes.h
@@ -941,7 +941,7 @@ struct dirfrag_t {
 WRITE_CLASS_ENCODER(dirfrag_t)
 
 
-inline std::ostream& operator<<(std::ostream& out, const dirfrag_t df) {
+inline std::ostream& operator<<(std::ostream& out, const dirfrag_t &df) {
   out << df.ino;
   if (!df.frag.is_root()) out << "." << df.frag;
   return out;