osdc: optimize the code doing the BufferHead mapping

get rid of the "newbl"
Signed-off-by: dongdong tao <tdd21151186@gmail.com>

diff --git a/src/osdc/ObjectCacher.cc b/src/osdc/ObjectCacher.cc
index 50f9a8d6a6c07de069bcb044606fc2eff1258c51..8d524ca0898792399ecf19ad009a3bb4db59b15f 100644 (file)
--- a/src/osdc/ObjectCacher.cc
+++ b/src/osdc/ObjectCacher.cc
@@ -1733,15 +1733,13 @@ int ObjectCacher::writex(OSDWrite *wr, ObjectSet *oset, Context *onfreespace,
 
       // get the frag we're mapping in
       bufferlist frag;
-      frag.substr_of(wr->bl,
-                    f_it->first, f_it->second);
+      frag.substr_of(wr->bl, f_it->first, f_it->second);
 
       // keep anything left of bhoff
-      bufferlist newbl;
-      if (bhoff)
-       newbl.substr_of(bh->bl, 0, bhoff);
-      newbl.claim_append(frag);
-      bh->bl.swap(newbl);
+      if (!bhoff)
+        bh->bl.swap(frag);
+      else
+        bh->bl.claim_append(frag);
 
       opos += f_it->second;
     }