buffer: In rebuild_page_aligned for the last ptr is page aligned, no need call rebuild().

This only happen for the last ptr. Because rebuild() don't change the len
of ptr, so if last ptr isn't page-size aligned but is page aligned, the
rebuild() don't change anything.

Signed-off-by: Ma Jianpeng <jianpeng.ma@intel.com>

diff --git a/src/common/buffer.cc b/src/common/buffer.cc
index 7617c2f530b8b37b42d33314ab33a5fb3689f9d8..b1417591bff5c27d2cd3138245060ebff1660261 100644 (file)
--- a/src/common/buffer.cc
+++ b/src/common/buffer.cc
@@ -1133,8 +1133,10 @@ void buffer::list::rebuild_page_aligned()
             (!p->is_page_aligned() ||
              !p->is_n_page_sized() ||
              (offset & ~CEPH_PAGE_MASK)));
-    ptr nb(buffer::create_page_aligned(unaligned._len));
-    unaligned.rebuild(nb);
+    if (!(unaligned.is_contiguous() && unaligned._buffers.front().is_page_aligned())) {
+      ptr nb(buffer::create_page_aligned(unaligned._len));
+      unaligned.rebuild(nb);
+    }
     _buffers.insert(p, unaligned._buffers.front());
   }
 }